Changeset - 8da52bdbcaa7
[Not reviewed]
0 7 0
MH - 3 years ago 2022-04-22 11:32:53
contact@maxhenger.nl
Initial extension of error-handling to detect pre-sync errors
7 files changed with 67 insertions and 30 deletions:
0 comments (0 inline, 0 general)
src/protocol/eval/executor.rs
Show inline comments
 
@@ -347,769 +347,769 @@ impl Prompt {
 
                            let rhs = cur_frame.expr_values.pop_back().unwrap();
 
                            let result = apply_binary_operator(&mut self.store, &lhs, expr.operation, &rhs);
 
                            cur_frame.expr_values.push_back(result);
 
                            self.store.drop_value(lhs.get_heap_pos());
 
                            self.store.drop_value(rhs.get_heap_pos());
 
                        },
 
                        Expression::Unary(expr) => {
 
                            let val = cur_frame.expr_values.pop_back().unwrap();
 
                            let result = apply_unary_operator(&mut self.store, expr.operation, &val);
 
                            cur_frame.expr_values.push_back(result);
 
                            self.store.drop_value(val.get_heap_pos());
 
                        },
 
                        Expression::Indexing(_expr) => {
 
                            // Evaluate index. Never heap allocated so we do
 
                            // not have to drop it.
 
                            let index = cur_frame.expr_values.pop_back().unwrap();
 
                            let index = self.store.maybe_read_ref(&index);
 

	
 
                            debug_assert!(index.is_integer());
 
                            let index = if index.is_signed_integer() {
 
                                index.as_signed_integer() as i64
 
                            } else {
 
                                index.as_unsigned_integer() as i64
 
                            };
 

	
 
                            let subject = cur_frame.expr_values.pop_back().unwrap();
 

	
 
                            let (deallocate_heap_pos, value_to_push) = match subject {
 
                                Value::Ref(value_ref) => {
 
                                    // Our expression stack value is a reference to something that
 
                                    // exists in the normal stack/heap. We don't want to deallocate
 
                                    // this thing. Rather we want to return a reference to it.
 
                                    let subject = self.store.read_ref(value_ref);
 
                                    let subject_heap_pos = match subject {
 
                                        Value::String(v) => *v,
 
                                        Value::Array(v) => *v,
 
                                        Value::Message(v) => *v,
 
                                        _ => unreachable!(),
 
                                    };
 

	
 
                                    if array_inclusive_index_is_invalid(&self.store, subject_heap_pos, index) {
 
                                        return Err(construct_array_error(self, modules, heap, expr_id, subject_heap_pos, index));
 
                                    }
 

	
 
                                    (None, Value::Ref(ValueId::Heap(subject_heap_pos, index as u32)))
 
                                },
 
                                _ => {
 
                                    // Our value lives on the expression stack, hence we need to
 
                                    // clone whatever we're referring to. Then drop the subject.
 
                                    let subject_heap_pos = match &subject {
 
                                        Value::String(v) => *v,
 
                                        Value::Array(v) => *v,
 
                                        Value::Message(v) => *v,
 
                                        _ => unreachable!(),
 
                                    };
 

	
 
                                    if array_inclusive_index_is_invalid(&self.store, subject_heap_pos, index) {
 
                                        return Err(construct_array_error(self, modules, heap, expr_id, subject_heap_pos, index));
 
                                    }
 

	
 
                                    let subject_indexed = Value::Ref(ValueId::Heap(subject_heap_pos, index as u32));
 
                                    (Some(subject_heap_pos), self.store.clone_value(subject_indexed))
 
                                },
 
                            };
 

	
 
                            cur_frame.expr_values.push_back(value_to_push);
 
                            self.store.drop_value(deallocate_heap_pos);
 
                        },
 
                        Expression::Slicing(expr) => {
 
                            // Evaluate indices
 
                            let from_index = cur_frame.expr_values.pop_back().unwrap();
 
                            let from_index = self.store.maybe_read_ref(&from_index);
 
                            let to_index = cur_frame.expr_values.pop_back().unwrap();
 
                            let to_index = self.store.maybe_read_ref(&to_index);
 

	
 
                            debug_assert!(from_index.is_integer() && to_index.is_integer());
 
                            let from_index = if from_index.is_signed_integer() {
 
                                from_index.as_signed_integer()
 
                            } else {
 
                                from_index.as_unsigned_integer() as i64
 
                            };
 
                            let to_index = if to_index.is_signed_integer() {
 
                                to_index.as_signed_integer()
 
                            } else {
 
                                to_index.as_unsigned_integer() as i64
 
                            };
 

	
 
                            // Dereference subject if needed
 
                            let subject = cur_frame.expr_values.pop_back().unwrap();
 
                            let deref_subject = self.store.maybe_read_ref(&subject);
 

	
 
                            // Slicing needs to produce a copy anyway (with the
 
                            // current evaluator implementation)
 
                            enum ValueKind{ Array, String, Message }
 
                            let (value_kind, array_heap_pos) = match deref_subject {
 
                                Value::Array(v) => (ValueKind::Array, *v),
 
                                Value::String(v) => (ValueKind::String, *v),
 
                                Value::Message(v) => (ValueKind::Message, *v),
 
                                _ => unreachable!()
 
                            };
 

	
 
                            if array_inclusive_index_is_invalid(&self.store, array_heap_pos, from_index) {
 
                                return Err(construct_array_error(self, modules, heap, expr.from_index, array_heap_pos, from_index));
 
                            }
 
                            if array_exclusive_index_is_invalid(&self.store, array_heap_pos, to_index) {
 
                                return Err(construct_array_error(self, modules, heap, expr.to_index, array_heap_pos, to_index));
 
                            }
 

	
 
                            // Again: would love to push directly, but rust...
 
                            let new_heap_pos = self.store.alloc_heap();
 
                            debug_assert!(self.store.heap_regions[new_heap_pos as usize].values.is_empty());
 
                            if to_index > from_index {
 
                                let from_index = from_index as usize;
 
                                let to_index = to_index as usize;
 
                                let mut values = Vec::with_capacity(to_index - from_index);
 
                                for idx in from_index..to_index {
 
                                    let value = self.store.heap_regions[array_heap_pos as usize].values[idx].clone();
 
                                    values.push(self.store.clone_value(value));
 
                                }
 

	
 
                                self.store.heap_regions[new_heap_pos as usize].values = values;
 

	
 
                            } // else: empty range
 

	
 
                            cur_frame.expr_values.push_back(match value_kind {
 
                                ValueKind::Array => Value::Array(new_heap_pos),
 
                                ValueKind::String => Value::String(new_heap_pos),
 
                                ValueKind::Message => Value::Message(new_heap_pos),
 
                            });
 

	
 
                            // Dropping the original subject, because we don't
 
                            // want to drop something on the stack
 
                            self.store.drop_value(subject.get_heap_pos());
 
                        },
 
                        Expression::Select(expr) => {
 
                            let subject= cur_frame.expr_values.pop_back().unwrap();
 
                            let mono_data = &heap[cur_frame.definition].monomorphs[cur_frame.monomorph_index];
 
                            let field_idx = mono_data.expr_info[expr.type_index as usize].variant.as_select() as u32;
 

	
 
                            // Note: same as above: clone if value lives on expr stack, simply
 
                            // refer to it if it already lives on the stack/heap.
 
                            let (deallocate_heap_pos, value_to_push) = match subject {
 
                                Value::Ref(value_ref) => {
 
                                    let subject = self.store.read_ref(value_ref);
 
                                    let subject_heap_pos = match expr.kind {
 
                                        SelectKind::StructField(_) => subject.as_struct(),
 
                                        SelectKind::TupleMember(_) => subject.as_tuple(),
 
                                    };
 

	
 
                                    (None, Value::Ref(ValueId::Heap(subject_heap_pos, field_idx)))
 
                                },
 
                                _ => {
 
                                    let subject_heap_pos = match expr.kind {
 
                                        SelectKind::StructField(_) => subject.as_struct(),
 
                                        SelectKind::TupleMember(_) => subject.as_tuple(),
 
                                    };
 
                                    let subject_indexed = Value::Ref(ValueId::Heap(subject_heap_pos, field_idx));
 
                                    (Some(subject_heap_pos), self.store.clone_value(subject_indexed))
 
                                },
 
                            };
 

	
 
                            cur_frame.expr_values.push_back(value_to_push);
 
                            self.store.drop_value(deallocate_heap_pos);
 
                        },
 
                        Expression::Literal(expr) => {
 
                            let value = match &expr.value {
 
                                Literal::Null => Value::Null,
 
                                Literal::True => Value::Bool(true),
 
                                Literal::False => Value::Bool(false),
 
                                Literal::Character(lit_value) => Value::Char(*lit_value),
 
                                Literal::Bytestring(lit_value) => {
 
                                    let heap_pos = self.store.alloc_heap();
 
                                    let values = &mut self.store.heap_regions[heap_pos as usize].values;
 
                                    debug_assert!(values.is_empty());
 
                                    values.reserve(lit_value.len());
 
                                    for byte in lit_value {
 
                                        values.push(Value::UInt8(*byte));
 
                                    }
 
                                    Value::Array(heap_pos)
 
                                }
 
                                Literal::String(lit_value) => {
 
                                    let heap_pos = self.store.alloc_heap();
 
                                    let values = &mut self.store.heap_regions[heap_pos as usize].values;
 
                                    let value = lit_value.as_str();
 
                                    debug_assert!(values.is_empty());
 
                                    values.reserve(value.len());
 
                                    for character in value.as_bytes() {
 
                                        debug_assert!(character.is_ascii());
 
                                        values.push(Value::Char(*character as char));
 
                                    }
 
                                    Value::String(heap_pos)
 
                                }
 
                                Literal::Integer(lit_value) => {
 
                                    use ConcreteTypePart as CTP;
 
                                    let mono_data = &heap[cur_frame.definition].monomorphs[cur_frame.monomorph_index];
 
                                    let type_id = mono_data.expr_info[expr.type_index as usize].type_id;
 
                                    let concrete_type = &types.get_monomorph(type_id).concrete_type;
 

	
 
                                    debug_assert_eq!(concrete_type.parts.len(), 1);
 
                                    match concrete_type.parts[0] {
 
                                        CTP::UInt8  => Value::UInt8(lit_value.unsigned_value as u8),
 
                                        CTP::UInt16 => Value::UInt16(lit_value.unsigned_value as u16),
 
                                        CTP::UInt32 => Value::UInt32(lit_value.unsigned_value as u32),
 
                                        CTP::UInt64 => Value::UInt64(lit_value.unsigned_value as u64),
 
                                        CTP::SInt8  => Value::SInt8(lit_value.unsigned_value as i8),
 
                                        CTP::SInt16 => Value::SInt16(lit_value.unsigned_value as i16),
 
                                        CTP::SInt32 => Value::SInt32(lit_value.unsigned_value as i32),
 
                                        CTP::SInt64 => Value::SInt64(lit_value.unsigned_value as i64),
 
                                        _ => unreachable!("got concrete type {:?} for integer literal at expr {:?}", concrete_type, expr_id),
 
                                    }
 
                                }
 
                                Literal::Struct(lit_value) => {
 
                                    let heap_pos = transfer_expression_values_front_into_heap(
 
                                        cur_frame, &mut self.store, lit_value.fields.len()
 
                                    );
 
                                    Value::Struct(heap_pos)
 
                                }
 
                                Literal::Enum(lit_value) => {
 
                                    Value::Enum(lit_value.variant_idx as i64)
 
                                }
 
                                Literal::Union(lit_value) => {
 
                                    let heap_pos = transfer_expression_values_front_into_heap(
 
                                        cur_frame, &mut self.store, lit_value.values.len()
 
                                    );
 
                                    Value::Union(lit_value.variant_idx as i64, heap_pos)
 
                                }
 
                                Literal::Array(lit_value) => {
 
                                    let heap_pos = transfer_expression_values_front_into_heap(
 
                                        cur_frame, &mut self.store, lit_value.len()
 
                                    );
 
                                    Value::Array(heap_pos)
 
                                }
 
                                Literal::Tuple(lit_value) => {
 
                                    let heap_pos = transfer_expression_values_front_into_heap(
 
                                        cur_frame, &mut self.store, lit_value.len()
 
                                    );
 
                                    Value::Tuple(heap_pos)
 
                                }
 
                            };
 

	
 
                            cur_frame.expr_values.push_back(value);
 
                        },
 
                        Expression::Cast(expr) => {
 
                            let mono_data = &heap[cur_frame.definition].monomorphs[cur_frame.monomorph_index];
 
                            let type_id = mono_data.expr_info[expr.type_index as usize].type_id;
 
                            let concrete_type = &types.get_monomorph(type_id).concrete_type;
 

	
 
                            // Typechecking reduced this to two cases: either we
 
                            // have casting noop (same types), or we're casting
 
                            // between integer/bool/char types.
 
                            let subject = cur_frame.expr_values.pop_back().unwrap();
 
                            match apply_casting(&mut self.store, concrete_type, &subject) {
 
                                Ok(value) => cur_frame.expr_values.push_back(value),
 
                                Err(msg) => {
 
                                    return Err(EvalError::new_error_at_expr(self, modules, heap, expr.this.upcast(), msg));
 
                                }
 
                            }
 

	
 
                            self.store.drop_value(subject.get_heap_pos());
 
                        }
 
                        Expression::Call(expr) => {
 
                            // If we're dealing with a builtin we don't do any
 
                            // fancy shenanigans at all, just push the result.
 
                            match expr.method {
 
                                Method::Get => {
 
                                    let value = cur_frame.expr_values.pop_front().unwrap();
 
                                    let value = self.store.maybe_read_ref(&value).clone();
 

	
 
                                    let port_id = if let Value::Input(port_id) = value {
 
                                        port_id
 
                                    } else {
 
                                        unreachable!("executor calling 'get' on value {:?}", value)
 
                                    };
 

	
 
                                    match ctx.performed_get(port_id) {
 
                                        Some(result) => {
 
                                            // We have the result. Merge the `ValueGroup` with the
 
                                            // stack/heap storage.
 
                                            debug_assert_eq!(result.values.len(), 1);
 
                                            result.into_stack(&mut cur_frame.expr_values, &mut self.store);
 
                                        },
 
                                        None => {
 
                                            // Don't have the result yet, prepare the expression to
 
                                            // get run again after we've received a message.
 
                                            cur_frame.expr_values.push_front(value.clone());
 
                                            cur_frame.expr_stack.push_back(ExprInstruction::EvalExpr(expr_id));
 
                                            return Ok(EvalContinuation::BlockGet(expr_id, port_id));
 
                                        }
 
                                    }
 
                                },
 
                                Method::Put => {
 
                                    let port_value = cur_frame.expr_values.pop_front().unwrap();
 
                                    let deref_port_value = self.store.maybe_read_ref(&port_value).clone();
 

	
 
                                    let port_id = if let Value::Output(port_id) = deref_port_value {
 
                                        port_id
 
                                    } else {
 
                                        unreachable!("executor calling 'put' on value {:?}", deref_port_value)
 
                                    };
 

	
 
                                    let msg_value = cur_frame.expr_values.pop_front().unwrap();
 
                                    let deref_msg_value = self.store.maybe_read_ref(&msg_value).clone();
 

	
 
                                    if ctx.performed_put(port_id) {
 
                                        // We're fine, deallocate in case the expression value stack
 
                                        // held an owned value
 
                                        self.store.drop_value(msg_value.get_heap_pos());
 
                                    } else {
 
                                        // Prepare to execute again
 
                                        cur_frame.expr_values.push_front(msg_value);
 
                                        cur_frame.expr_values.push_front(port_value);
 
                                        cur_frame.expr_stack.push_back(ExprInstruction::EvalExpr(expr_id));
 
                                        let value_group = ValueGroup::from_store(&self.store, &[deref_msg_value]);
 
                                        return Ok(EvalContinuation::Put(expr_id, port_id, value_group));
 
                                    }
 
                                },
 
                                Method::Fires => {
 
                                    let port_value = cur_frame.expr_values.pop_front().unwrap();
 
                                    let port_value_deref = self.store.maybe_read_ref(&port_value).clone();
 
                                    let port_id = port_value_deref.as_port_id();
 

	
 
                                    match ctx.fires(port_id) {
 
                                        None => {
 
                                            cur_frame.expr_values.push_front(port_value);
 
                                            cur_frame.expr_stack.push_back(ExprInstruction::EvalExpr(expr_id));
 
                                            return Ok(EvalContinuation::BlockFires(port_id));
 
                                        },
 
                                        Some(value) => {
 
                                            cur_frame.expr_values.push_back(value);
 
                                        }
 
                                    }
 
                                },
 
                                Method::Create => {
 
                                    let length_value = cur_frame.expr_values.pop_front().unwrap();
 
                                    let length_value = self.store.maybe_read_ref(&length_value);
 
                                    let length = if length_value.is_signed_integer() {
 
                                        let length_value = length_value.as_signed_integer();
 
                                        if length_value < 0 {
 
                                            return Err(EvalError::new_error_at_expr(
 
                                                self, modules, heap, expr_id,
 
                                                format!("got length '{}', can only create a message with a non-negative length", length_value)
 
                                            ));
 
                                        }
 

	
 
                                        length_value as u64
 
                                    } else {
 
                                        debug_assert!(length_value.is_unsigned_integer());
 
                                        length_value.as_unsigned_integer()
 
                                    };
 

	
 
                                    let heap_pos = self.store.alloc_heap();
 
                                    let values = &mut self.store.heap_regions[heap_pos as usize].values;
 
                                    debug_assert!(values.is_empty());
 
                                    values.resize(length as usize, Value::UInt8(0));
 
                                    cur_frame.expr_values.push_back(Value::Message(heap_pos));
 
                                },
 
                                Method::Length => {
 
                                    let value = cur_frame.expr_values.pop_front().unwrap();
 
                                    let value_heap_pos = value.get_heap_pos();
 
                                    let value = self.store.maybe_read_ref(&value);
 

	
 
                                    let heap_pos = match value {
 
                                        Value::Array(pos) => *pos,
 
                                        Value::String(pos) => *pos,
 
                                        _ => unreachable!("length(...) on {:?}", value),
 
                                    };
 

	
 
                                    let len = self.store.heap_regions[heap_pos as usize].values.len();
 

	
 
                                    // TODO: @PtrInt
 
                                    cur_frame.expr_values.push_back(Value::UInt32(len as u32));
 
                                    self.store.drop_value(value_heap_pos);
 
                                },
 
                                Method::Assert => {
 
                                    let value = cur_frame.expr_values.pop_front().unwrap();
 
                                    let value = self.store.maybe_read_ref(&value).clone();
 
                                    if !value.as_bool() {
 
                                        return Ok(EvalContinuation::BranchInconsistent)
 
                                    }
 
                                },
 
                                Method::Print => {
 
                                    // Convert the runtime-variant of a string
 
                                    // into an actual string.
 
                                    let value = cur_frame.expr_values.pop_front().unwrap();
 
                                    let mut is_literal_string = value.get_heap_pos().is_some();
 
                                    let is_literal_string = value.get_heap_pos().is_some();
 
                                    let value = self.store.maybe_read_ref(&value);
 
                                    let value_heap_pos = value.as_string();
 
                                    let elements = &self.store.heap_regions[value_heap_pos as usize].values;
 

	
 
                                    let mut message = String::with_capacity(elements.len());
 
                                    for element in elements {
 
                                        message.push(element.as_char());
 
                                    }
 

	
 
                                    // Drop the heap-allocated value from the
 
                                    // store
 
                                    if is_literal_string {
 
                                        self.store.drop_heap_pos(value_heap_pos);
 
                                    }
 

	
 
                                    println!("{}", message);
 
                                },
 
                                Method::SelectStart => {
 
                                    let num_cases = self.store.maybe_read_ref(&cur_frame.expr_values.pop_front().unwrap()).as_uint32();
 
                                    let num_ports = self.store.maybe_read_ref(&cur_frame.expr_values.pop_front().unwrap()).as_uint32();
 

	
 
                                    return Ok(EvalContinuation::SelectStart(num_cases, num_ports));
 
                                },
 
                                Method::SelectRegisterCasePort => {
 
                                    let case_index = self.store.maybe_read_ref(&cur_frame.expr_values.pop_front().unwrap()).as_uint32();
 
                                    let port_index = self.store.maybe_read_ref(&cur_frame.expr_values.pop_front().unwrap()).as_uint32();
 
                                    let port_value = self.store.maybe_read_ref(&cur_frame.expr_values.pop_front().unwrap()).as_port_id();
 

	
 
                                    return Ok(EvalContinuation::SelectRegisterPort(expr_id, case_index, port_index, port_value));
 
                                },
 
                                Method::SelectWait => {
 
                                    match ctx.performed_select_wait() {
 
                                        Some(select_index) => {
 
                                            cur_frame.expr_values.push_back(Value::UInt32(select_index));
 
                                        },
 
                                        None => {
 
                                            cur_frame.expr_stack.push_back(ExprInstruction::EvalExpr(expr.this.upcast()));
 
                                            return Ok(EvalContinuation::SelectWait)
 
                                        },
 
                                    }
 
                                },
 
                                Method::ComponentRandomU32 | Method::ComponentTcpClient => {
 
                                    debug_assert_eq!(heap[expr.procedure].parameters.len(), cur_frame.expr_values.len());
 
                                    debug_assert_eq!(heap[cur_frame.position].as_new().expression, expr.this);
 
                                },
 
                                Method::UserComponent => {
 
                                    // This is actually handled by the evaluation
 
                                    // of the statement.
 
                                    debug_assert_eq!(heap[expr.procedure].parameters.len(), cur_frame.expr_values.len());
 
                                    debug_assert_eq!(heap[cur_frame.position].as_new().expression, expr.this);
 
                                },
 
                                Method::UserFunction => {
 
                                    // Push a new frame. Note that all expressions have
 
                                    // been pushed to the front, so they're in the order
 
                                    // of the definition.
 
                                    let num_args = expr.arguments.len();
 

	
 
                                    // Determine stack boundaries
 
                                    let cur_stack_boundary = self.store.cur_stack_boundary;
 
                                    let new_stack_boundary = self.store.stack.len();
 

	
 
                                    // Push new boundary and function arguments for new frame
 
                                    self.store.stack.push(Value::PrevStackBoundary(cur_stack_boundary as isize));
 
                                    for _ in 0..num_args {
 
                                        let argument = self.store.read_take_ownership(cur_frame.expr_values.pop_front().unwrap());
 
                                        self.store.stack.push(argument);
 
                                    }
 

	
 
                                    // Determine the monomorph index of the function we're calling
 
                                    let mono_data = &heap[cur_frame.definition].monomorphs[cur_frame.monomorph_index];
 
                                    let (type_id, monomorph_index) = mono_data.expr_info[expr.type_index as usize].variant.as_procedure();
 

	
 
                                    // Push the new frame and reserve its stack size
 
                                    let new_frame = Frame::new(heap, expr.procedure, type_id, monomorph_index);
 
                                    let new_stack_size = new_frame.max_stack_size;
 
                                    self.frames.push(new_frame);
 
                                    self.store.cur_stack_boundary = new_stack_boundary;
 
                                    self.store.reserve_stack(new_stack_size);
 

	
 
                                    // To simplify the logic a little bit we will now
 
                                    // return and ask our caller to call us again
 
                                    return Ok(EvalContinuation::Stepping);
 
                                }
 
                            }
 
                        },
 
                        Expression::Variable(expr) => {
 
                            let variable = &heap[expr.declaration.unwrap()];
 
                            let ref_value = if expr.used_as_binding_target {
 
                                Value::Binding(variable.unique_id_in_scope as StackPos)
 
                            } else {
 
                                Value::Ref(ValueId::Stack(variable.unique_id_in_scope as StackPos))
 
                            };
 
                            cur_frame.expr_values.push_back(ref_value);
 
                        }
 
                    }
 
                }
 
            }
 
        }
 

	
 
        debug_log!("Frame [{:?}] at {:?}", cur_frame.definition, cur_frame.position);
 
        if debug_enabled!() {
 
            debug_log!("Expression value stack (size = {}):", cur_frame.expr_values.len());
 
            for (_stack_idx, _stack_val) in cur_frame.expr_values.iter().enumerate() {
 
                debug_log!("  [{:03}] {:?}", _stack_idx, _stack_val);
 
            }
 

	
 
            debug_log!("Stack (size = {}):", self.store.stack.len());
 
            for (_stack_idx, _stack_val) in self.store.stack.iter().enumerate() {
 
                debug_log!("  [{:03}] {:?}", _stack_idx, _stack_val);
 
            }
 

	
 
            debug_log!("Heap:");
 
            for (_heap_idx, _heap_region) in self.store.heap_regions.iter().enumerate() {
 
                let _is_free = self.store.free_regions.iter().any(|idx| *idx as usize == _heap_idx);
 
                debug_log!("  [{:03}] in_use: {}, len: {}, vals: {:?}", _heap_idx, !_is_free, _heap_region.values.len(), &_heap_region.values);
 
            }
 
        }
 
        // No (more) expressions to evaluate. So evaluate statement (that may
 
        // depend on the result on the last evaluated expression(s))
 
        let stmt = &heap[cur_frame.position];
 
        let return_value = match stmt {
 
            Statement::Block(stmt) => {
 
                debug_assert!(stmt.statements.is_empty() || stmt.next == stmt.statements[0]);
 
                cur_frame.position = stmt.next;
 
                Ok(EvalContinuation::Stepping)
 
            },
 
            Statement::EndBlock(stmt) => {
 
                let block = &heap[stmt.start_block];
 
                let scope = &heap[block.scope];
 
                self.store.clear_stack(scope.first_unique_id_in_scope as usize);
 
                cur_frame.position = stmt.next;
 

	
 
                Ok(EvalContinuation::Stepping)
 
            },
 
            Statement::Local(stmt) => {
 
                match stmt {
 
                    LocalStatement::Memory(stmt) => {
 
                        dbg_code!({
 
                            let variable = &heap[stmt.variable];
 
                            debug_assert!(match self.store.read_ref(ValueId::Stack(variable.unique_id_in_scope as u32)) {
 
                                Value::Unassigned => false,
 
                                _ => true,
 
                            });
 
                        });
 

	
 
                        cur_frame.position = stmt.next;
 
                        Ok(EvalContinuation::Stepping)
 
                    },
 
                    LocalStatement::Channel(stmt) => {
 
                        // Need to create a new channel by requesting it from
 
                        // the runtime.
 
                        match ctx.created_channel() {
 
                            None => {
 
                                // No channel is pending. So request one
 
                                    Ok(EvalContinuation::NewChannel)
 
                            },
 
                            Some((put_port, get_port)) => {
 
                                self.store.write(ValueId::Stack(heap[stmt.from].unique_id_in_scope as u32), put_port);
 
                                self.store.write(ValueId::Stack(heap[stmt.to].unique_id_in_scope as u32), get_port);
 
                                cur_frame.position = stmt.next;
 
                                Ok(EvalContinuation::Stepping)
 
                            }
 
                        }
 
                    }
 
                }
 
            },
 
            Statement::Labeled(stmt) => {
 
                cur_frame.position = stmt.body;
 

	
 
                Ok(EvalContinuation::Stepping)
 
            },
 
            Statement::If(stmt) => {
 
                debug_assert_eq!(cur_frame.expr_values.len(), 1, "expected one expr value for if statement");
 
                let test_value = cur_frame.expr_values.pop_back().unwrap();
 
                let test_value = self.store.maybe_read_ref(&test_value).as_bool();
 
                if test_value {
 
                    cur_frame.position = stmt.true_case.body;
 
                } else if let Some(false_body) = stmt.false_case {
 
                    cur_frame.position = false_body.body;
 
                } else {
 
                    // Not true, and no false body
 
                    cur_frame.position = stmt.end_if.upcast();
 
                }
 

	
 
                Ok(EvalContinuation::Stepping)
 
            },
 
            Statement::EndIf(stmt) => {
 
                cur_frame.position = stmt.next;
 
                let if_stmt = &heap[stmt.start_if];
 
                debug_assert_eq!(
 
                    heap[if_stmt.true_case.scope].first_unique_id_in_scope,
 
                    heap[if_stmt.false_case.unwrap_or(if_stmt.true_case).scope].first_unique_id_in_scope,
 
                );
 
                let scope = &heap[if_stmt.true_case.scope];
 
                self.store.clear_stack(scope.first_unique_id_in_scope as usize);
 
                Ok(EvalContinuation::Stepping)
 
            },
 
            Statement::While(stmt) => {
 
                debug_assert_eq!(cur_frame.expr_values.len(), 1, "expected one expr value for while statement");
 
                let test_value = cur_frame.expr_values.pop_back().unwrap();
 
                let test_value = self.store.maybe_read_ref(&test_value).as_bool();
 
                if test_value {
 
                    cur_frame.position = stmt.body;
 
                } else {
 
                    cur_frame.position = stmt.end_while.upcast();
 
                }
 

	
 
                Ok(EvalContinuation::Stepping)
 
            },
 
            Statement::EndWhile(stmt) => {
 
                cur_frame.position = stmt.next;
 
                let start_while = &heap[stmt.start_while];
 
                let scope = &heap[start_while.scope];
 
                self.store.clear_stack(scope.first_unique_id_in_scope as usize);
 
                Ok(EvalContinuation::Stepping)
 
            },
 
            Statement::Break(stmt) => {
 
                cur_frame.position = stmt.target.upcast();
 

	
 
                Ok(EvalContinuation::Stepping)
 
            },
 
            Statement::Continue(stmt) => {
 
                cur_frame.position = stmt.target.upcast();
 

	
 
                Ok(EvalContinuation::Stepping)
 
            },
 
            Statement::Synchronous(stmt) => {
 
                cur_frame.position = stmt.body;
 

	
 
                Ok(EvalContinuation::SyncBlockStart)
 
            },
 
            Statement::EndSynchronous(stmt) => {
 
                cur_frame.position = stmt.next;
 
                let start_synchronous = &heap[stmt.start_sync];
 
                let scope = &heap[start_synchronous.scope];
 
                self.store.clear_stack(scope.first_unique_id_in_scope as usize);
 

	
 
                Ok(EvalContinuation::SyncBlockEnd)
 
            },
 
            Statement::Fork(stmt) => {
 
                if stmt.right_body.is_none() {
 
                    // No reason to fork
 
                    cur_frame.position = stmt.left_body;
 
                } else {
 
                    // Need to fork
 
                    if let Some(go_left) = ctx.performed_fork() {
 
                        // Runtime has created a fork
 
                        if go_left {
 
                            cur_frame.position = stmt.left_body;
 
                        } else {
 
                            cur_frame.position = stmt.right_body.unwrap();
 
                        }
 
                    } else {
 
                        // Request the runtime to create a fork of the current
 
                        // branch
 
                        return Ok(EvalContinuation::NewFork);
 
                    }
 
                }
 

	
 
                Ok(EvalContinuation::Stepping)
 
            },
 
            Statement::EndFork(stmt) => {
 
                cur_frame.position = stmt.next;
 

	
 
                Ok(EvalContinuation::Stepping)
 
            },
 
            Statement::Select(stmt) => {
 
                // This is a trampoline for the statements that were placed by
 
                // the AST transformation pass
 
                cur_frame.position = stmt.next;
 

	
 
                Ok(EvalContinuation::Stepping)
 
            },
 
            Statement::EndSelect(stmt) => {
 
                cur_frame.position = stmt.next;
 
                let start_select = &heap[stmt.start_select];
 
                if let Some(select_case) = start_select.cases.first() {
 
                    let scope = &heap[select_case.scope];
 
                    self.store.clear_stack(scope.first_unique_id_in_scope as usize);
 
                }
 

	
 
                Ok(EvalContinuation::Stepping)
 
            },
 
            Statement::Return(_stmt) => {
 
                debug_assert_eq!(cur_frame.expr_values.len(), 1, "expected one expr value for return statement");
 

	
 
                // The preceding frame has executed a call, so is expecting the
 
                // return expression on its expression value stack. Note that
 
                // we may be returning a reference to something on our stack,
 
                // so we need to read that value and clone it.
 
                let return_value = cur_frame.expr_values.pop_back().unwrap();
 
                let return_value = match return_value {
 
                    Value::Ref(value_id) => self.store.read_copy(value_id),
 
                    _ => return_value,
 
                };
 

	
 
                // Pre-emptively pop our stack frame
 
                self.frames.pop();
 

	
 
                // Clean up our section of the stack
 
                self.store.clear_stack(0);
 
                self.store.stack.truncate(self.store.cur_stack_boundary + 1);
 
                let prev_stack_idx = self.store.stack.pop().unwrap().as_stack_boundary();
 

	
 
                // TODO: Temporary hack for testing, remove at some point
 
                if self.frames.is_empty() {
 
                    debug_assert!(prev_stack_idx == -1);
 
                    debug_assert!(self.store.stack.len() == 0);
 
                    self.store.stack.push(return_value);
 
                    return Ok(EvalContinuation::ComponentTerminated);
 
                }
 

	
 
                debug_assert!(prev_stack_idx >= 0);
 
                // Return to original state of stack frame
 
                self.store.cur_stack_boundary = prev_stack_idx as usize;
 
                let cur_frame = self.frames.last_mut().unwrap();
 
                cur_frame.expr_values.push_back(return_value);
 

	
 
                // We just returned to the previous frame, which might be in
 
                // the middle of evaluating expressions for a particular
 
                // statement. So we don't want to enter the code below.
 
                return Ok(EvalContinuation::Stepping);
 
            },
 
            Statement::Goto(stmt) => {
 
                cur_frame.position = stmt.target.upcast();
 

	
 
                Ok(EvalContinuation::Stepping)
 
            },
 
            Statement::New(stmt) => {
 
                let call_expr = &heap[stmt.expression];
 
                debug_assert_eq!(
 
                    cur_frame.expr_values.len(), heap[call_expr.procedure].parameters.len(),
 
                    "mismatch in expr stack size and number of arguments for new statement"
 
                );
 

	
 
                let mono_data = &heap[cur_frame.definition].monomorphs[cur_frame.monomorph_index];
 
                let type_id = mono_data.expr_info[call_expr.type_index as usize].variant.as_procedure().0;
 

	
 
                // Note that due to expression value evaluation they exist in
 
                // reverse order on the stack.
 
                // TODO: Revise this code, keep it as is to be compatible with current runtime
 
                let mut args = Vec::new();
 
                while let Some(value) = cur_frame.expr_values.pop_front() {
 
                    args.push(value);
 
                }
 

	
 
                // Construct argument group, thereby copying heap regions
 
                let argument_group = ValueGroup::from_store(&self.store, &args);
 

	
 
                // Clear any heap regions
 
                for arg in &args {
 
                    self.store.drop_value(arg.get_heap_pos());
 
                }
 

	
 
                cur_frame.position = stmt.next;
 

	
 
                Ok(EvalContinuation::NewComponent(call_expr.procedure, type_id, argument_group))
 
            },
 
            Statement::Expression(stmt) => {
 
                // The expression has just been completely evaluated. Some
 
                // values might have remained on the expression value stack.
 
                // cur_frame.expr_values.clear(); PROPER CLEARING
 
                cur_frame.position = stmt.next;
 

	
 
                Ok(EvalContinuation::Stepping)
 
            },
 
        };
 

	
 
        assert!(
 
            cur_frame.expr_values.is_empty(),
 
            "This is a debugging assertion that will fail if you perform expressions without \
 
            assigning to anything. This should be completely valid, and this assertion should be \
 
            replaced by something that clears the expression values if needed, but I'll keep this \
 
            in for now for debugging purposes."
 
        );
 

	
 
        // If the next statement requires evaluating expressions then we push
 
        // these onto the expression stack. This way we will evaluate this
 
        // stack in the next loop, then evaluate the statement using the result
 
        // from the expression evaluation.
 
        if !cur_frame.position.is_invalid() {
 
            let stmt = &heap[cur_frame.position];
 

	
 
            match stmt {
src/protocol/parser/pass_rewriting.rs
Show inline comments
 
use crate::collections::*;
 
use crate::protocol::*;
 

	
 
use super::visitor::*;
 

	
 
pub(crate) struct PassRewriting {
 
    current_scope: ScopeId,
 
    current_procedure_id: ProcedureDefinitionId,
 
    definition_buffer: ScopedBuffer<DefinitionId>,
 
    statement_buffer: ScopedBuffer<StatementId>,
 
    call_expr_buffer: ScopedBuffer<CallExpressionId>,
 
    expression_buffer: ScopedBuffer<ExpressionId>,
 
    scope_buffer: ScopedBuffer<ScopeId>,
 
}
 

	
 
impl PassRewriting {
 
    pub(crate) fn new() -> Self {
 
        Self{
 
            current_scope: ScopeId::new_invalid(),
 
            current_procedure_id: ProcedureDefinitionId::new_invalid(),
 
            definition_buffer: ScopedBuffer::with_capacity(BUFFER_INIT_CAP_LARGE),
 
            statement_buffer: ScopedBuffer::with_capacity(BUFFER_INIT_CAP_SMALL),
 
            call_expr_buffer: ScopedBuffer::with_capacity(BUFFER_INIT_CAP_SMALL),
 
            expression_buffer: ScopedBuffer::with_capacity(BUFFER_INIT_CAP_SMALL),
 
            scope_buffer: ScopedBuffer::with_capacity(BUFFER_INIT_CAP_SMALL),
 
        }
 
    }
 
}
 

	
 
impl Visitor for PassRewriting {
 
    fn visit_module(&mut self, ctx: &mut Ctx) -> VisitorResult {
 
        let module = ctx.module();
 
        debug_assert_eq!(module.phase, ModuleCompilationPhase::Typed);
 

	
 
        let root_id = module.root_id;
 
        let root = &ctx.heap[root_id];
 
        let definition_section = self.definition_buffer.start_section_initialized(&root.definitions);
 
        for definition_index in 0..definition_section.len() {
 
            let definition_id = definition_section[definition_index];
 
            self.visit_definition(ctx, definition_id)?;
 
        }
 

	
 
        definition_section.forget();
 
        ctx.module_mut().phase = ModuleCompilationPhase::Rewritten;
 
        return Ok(())
 
    }
 

	
 
    // --- Visiting procedures
 

	
 
    fn visit_procedure_definition(&mut self, ctx: &mut Ctx, id: ProcedureDefinitionId) -> VisitorResult {
 
        let definition = &ctx.heap[id];
 
        if definition.source.is_builtin() {
 
            return Ok(());
 
        }
 

	
 
        let body_id = definition.body;
 
        self.current_scope = definition.scope;
 
        self.current_procedure_id = id;
 
        return self.visit_block_stmt(ctx, body_id);
 
    }
 

	
 
    // --- Visiting statements (that are not the select statement)
 

	
 
    fn visit_block_stmt(&mut self, ctx: &mut Ctx, id: BlockStatementId) -> VisitorResult {
 
        let block_stmt = &ctx.heap[id];
 
        let stmt_section = self.statement_buffer.start_section_initialized(&block_stmt.statements);
 

	
 
        self.current_scope = block_stmt.scope;
 
        for stmt_idx in 0..stmt_section.len() {
 
            self.visit_stmt(ctx, stmt_section[stmt_idx])?;
 
        }
 

	
 
        stmt_section.forget();
 
        return Ok(())
 
    }
 

	
 
    fn visit_labeled_stmt(&mut self, ctx: &mut Ctx, id: LabeledStatementId) -> VisitorResult {
 
        let labeled_stmt = &ctx.heap[id];
 
        let body_id = labeled_stmt.body;
 
        return self.visit_stmt(ctx, body_id);
 
    }
 

	
 
    fn visit_if_stmt(&mut self, ctx: &mut Ctx, id: IfStatementId) -> VisitorResult {
 
        let if_stmt = &ctx.heap[id];
 
        let true_case = if_stmt.true_case;
 
        let false_case = if_stmt.false_case;
 

	
 
        self.current_scope = true_case.scope;
 
        self.visit_stmt(ctx, true_case.body)?;
 
        if let Some(false_case) = false_case {
 
            self.current_scope = false_case.scope;
 
            self.visit_stmt(ctx, false_case.body)?;
 
        }
 

	
 
        return Ok(())
 
    }
 

	
 
    fn visit_while_stmt(&mut self, ctx: &mut Ctx, id: WhileStatementId) -> VisitorResult {
 
        let while_stmt = &ctx.heap[id];
 
        let body_id = while_stmt.body;
 
        self.current_scope = while_stmt.scope;
 
        return self.visit_stmt(ctx, body_id);
 
    }
 

	
 
    fn visit_synchronous_stmt(&mut self, ctx: &mut Ctx, id: SynchronousStatementId) -> VisitorResult {
 
        let sync_stmt = &ctx.heap[id];
 
        let body_id = sync_stmt.body;
 
        self.current_scope = sync_stmt.scope;
 
        return self.visit_stmt(ctx, body_id);
 
    }
 

	
 
    // --- Visiting the select statement
 

	
 
    fn visit_select_stmt(&mut self, ctx: &mut Ctx, id: SelectStatementId) -> VisitorResult {
 
        // Utility for the last stage of rewriting process. Note that caller
 
        // still needs to point the end of the if-statement to the end of the
 
        // replacement statement of the select statement.
 
        fn transform_select_case_code(
 
            ctx: &mut Ctx, containing_procedure_id: ProcedureDefinitionId,
 
            select_id: SelectStatementId, case_index: usize,
 
            select_var_id: VariableId, select_var_type_id: TypeIdReference
 
        ) -> (IfStatementId, EndIfStatementId, ScopeId) {
 
            // Retrieve statement IDs associated with case
 
            let case = &ctx.heap[select_id].cases[case_index];
 
            let case_guard_id = case.guard;
 
            let case_body_id = case.body;
 
            let case_scope_id = case.scope;
 

	
 
            // Create the if-statement for the result of the select statement
 
            let compare_expr_id = create_ast_equality_comparison_expr(ctx, containing_procedure_id, select_var_id, select_var_type_id, case_index as u64);
 
            let true_case = IfStatementCase{
 
                body: case_guard_id, // which is linked up to the body
 
                scope: case_scope_id,
 
            };
 
            let (if_stmt_id, end_if_stmt_id) = create_ast_if_stmt(ctx, compare_expr_id.upcast(), true_case, None);
 

	
 
            // Link up body statement to end-if
 
            set_ast_statement_next(ctx, case_body_id, end_if_stmt_id.upcast());
 

	
 
            return (if_stmt_id, end_if_stmt_id, case_scope_id);
 
        }
 

	
 
        // Precreate the block that will end up containing all of the
 
        // transformed statements. Also precreate the scope associated with it
 
        let (outer_block_id, outer_end_block_id, outer_scope_id) =
 
            create_ast_block_stmt(ctx, Vec::new());
 

	
 
        // The "select" and the "end select" statement will act like trampolines
 
        // that jump to the replacement block. So set the child/parent
 
        // relationship already.
 
        // --- for the statements
 
        let select_stmt = &mut ctx.heap[id];
 
        select_stmt.next = outer_block_id.upcast();
 
        let end_select_stmt_id = select_stmt.end_select;
 
        let select_stmt_relative_pos = select_stmt.relative_pos_in_parent;
 

	
 
        let outer_end_block_stmt = &mut ctx.heap[outer_end_block_id];
 
        outer_end_block_stmt.next = end_select_stmt_id.upcast();
 

	
 
        // --- for the scopes
 
        link_new_child_to_existing_parent_scope(ctx, &mut self.scope_buffer, self.current_scope, outer_scope_id, select_stmt_relative_pos);
 

	
 
        // Create statements that will create temporary variables for all of the
 
        // ports passed to the "get" calls in the select case guards.
 
        let select_stmt = &ctx.heap[id];
 
        let total_num_cases = select_stmt.cases.len();
 
        let mut total_num_ports = 0;
 
        let end_select_stmt_id = select_stmt.end_select;
 
        let _end_select = &ctx.heap[end_select_stmt_id];
 

	
 
        // Put heap IDs into temporary buffers to handle borrowing rules
 
        let mut call_id_section = self.call_expr_buffer.start_section();
 
        let mut expr_id_section = self.expression_buffer.start_section();
 

	
 
        for case in select_stmt.cases.iter() {
 
            total_num_ports += case.involved_ports.len();
 
            for (call_id, expr_id) in case.involved_ports.iter().copied() {
 
                call_id_section.push(call_id);
 
                expr_id_section.push(expr_id);
 
            }
 
        }
 

	
 
        // Transform all of the call expressions by takings its argument (the
 
        // port from which we `get`) and turning it into a temporary variable.
 
        let mut transformed_stmts = Vec::with_capacity(total_num_ports); // TODO: Recompute this preallocated length, put assert at the end
 
        let mut locals = Vec::with_capacity(total_num_ports);
 

	
 
        for port_var_idx in 0..call_id_section.len() {
 
            let get_call_expr_id = call_id_section[port_var_idx];
 
            let port_expr_id = expr_id_section[port_var_idx];
 
            let port_type_index = ctx.heap[port_expr_id].type_index();
 
            let port_type_ref = TypeIdReference::IndirectSameAsExpr(port_type_index);
 

	
 
            // Move the port expression such that it gets assigned to a temporary variable
 
            let variable_id = create_ast_variable(ctx, outer_scope_id);
 
            let variable_decl_stmt_id = create_ast_variable_declaration_stmt(ctx, self.current_procedure_id, variable_id, port_type_ref, port_expr_id);
 

	
 
            // Replace the original port expression in the call with a reference
 
            // to the replacement variable
 
            let variable_expr_id = create_ast_variable_expr(ctx, self.current_procedure_id, variable_id, port_type_ref);
 
            let call_expr = &mut ctx.heap[get_call_expr_id];
 
            call_expr.arguments[0] = variable_expr_id.upcast();
 

	
 
            transformed_stmts.push(variable_decl_stmt_id.upcast().upcast());
 
            locals.push((variable_id, port_type_ref));
 
        }
 

	
 
        // Insert runtime calls that facilitate the semantics of the select
 
        // block.
 

	
 
        // Create the call that indicates the start of the select block
 
        {
 
            let num_cases_expression_id = create_ast_literal_integer_expr(ctx, self.current_procedure_id, total_num_cases as u64, ctx.arch.uint32_type_id);
 
            let num_ports_expression_id = create_ast_literal_integer_expr(ctx, self.current_procedure_id, total_num_ports as u64, ctx.arch.uint32_type_id);
 
            let arguments = vec![
 
                num_cases_expression_id.upcast(),
 
                num_ports_expression_id.upcast()
 
            ];
 

	
 
            let call_expression_id = create_ast_call_expr(ctx, InputSpan::new(), self.current_procedure_id, Method::SelectStart, &mut self.expression_buffer, arguments);
 
            let call_statement_id = create_ast_expression_stmt(ctx, call_expression_id.upcast());
 

	
 
            transformed_stmts.push(call_statement_id.upcast());
 
        }
 

	
 
        // Create calls for each select case that will register the ports that
 
        // we are waiting on at the runtime.
 
        {
 
            let mut total_port_index = 0;
 
            for case_index in 0..total_num_cases {
 
                let case = &ctx.heap[id].cases[case_index];
 
                let case_num_ports = case.involved_ports.len();
 

	
 
                for case_port_index in 0..case_num_ports {
 
                    // Arguments to runtime call
 
                    let original_get_call_id = case.involved_ports[case_port_index].0;
 
                    // Retrieve original span in case of error reporting for the
 
                    // inserted function call
 
                    let original_get_call_id = ctx.heap[id].cases[case_index].involved_ports[case_port_index].0;
 
                    let original_get_call_span = ctx.heap[original_get_call_id].full_span;
 

	
 
                    // Arguments to runtime call
 
                    let (port_variable_id, port_variable_type) = locals[total_port_index]; // so far this variable contains the temporary variables for the port expressions
 
                    let case_index_expr_id = create_ast_literal_integer_expr(ctx, self.current_procedure_id, case_index as u64, ctx.arch.uint32_type_id);
 
                    let port_index_expr_id = create_ast_literal_integer_expr(ctx, self.current_procedure_id, case_port_index as u64, ctx.arch.uint32_type_id);
 
                    let port_variable_expr_id = create_ast_variable_expr(ctx, self.current_procedure_id, port_variable_id, port_variable_type);
 
                    let runtime_call_arguments = vec![
 
                        case_index_expr_id.upcast(),
 
                        port_index_expr_id.upcast(),
 
                        port_variable_expr_id.upcast()
 
                    ];
 

	
 
                    // Create runtime call, then store it
 
                    let runtime_call_expr_id = create_ast_call_expr(ctx, original_get_call_span, self.current_procedure_id, Method::SelectRegisterCasePort, &mut self.expression_buffer, runtime_call_arguments);
 
                    let runtime_call_stmt_id = create_ast_expression_stmt(ctx, runtime_call_expr_id.upcast());
 

	
 
                    transformed_stmts.push(runtime_call_stmt_id.upcast());
 

	
 
                    total_port_index += 1;
 
                }
 
            }
 
        }
 

	
 
        // Create the variable that will hold the result of a completed select
 
        // block. Then create the runtime call that will produce this result
 
        let select_variable_id = create_ast_variable(ctx, outer_scope_id);
 
        let select_variable_type = TypeIdReference::DirectTypeId(ctx.arch.uint32_type_id);
 
        locals.push((select_variable_id, select_variable_type));
 

	
 
        {
 
            let runtime_call_expr_id = create_ast_call_expr(ctx, InputSpan::new(), self.current_procedure_id, Method::SelectWait, &mut self.expression_buffer, Vec::new());
 
            let variable_stmt_id = create_ast_variable_declaration_stmt(ctx, self.current_procedure_id, select_variable_id, select_variable_type, runtime_call_expr_id.upcast());
 
            transformed_stmts.push(variable_stmt_id.upcast().upcast());
 
        }
 

	
 
        call_id_section.forget();
 
        expr_id_section.forget();
 

	
 
        // Now we transform each of the select block case's guard and code into
 
        // a chained if-else statement.
 
        let relative_pos = transformed_stmts.len() as i32;
 
        if total_num_cases > 0 {
 
            let (if_stmt_id, end_if_stmt_id, scope_id) = transform_select_case_code(ctx, self.current_procedure_id, id, 0, select_variable_id, select_variable_type);
 
            link_existing_child_to_new_parent_scope(ctx, &mut self.scope_buffer, outer_scope_id, scope_id, relative_pos);
 
            let first_end_if_stmt = &mut ctx.heap[end_if_stmt_id];
 
            first_end_if_stmt.next = outer_end_block_id.upcast();
 

	
 
            let mut last_if_stmt_id = if_stmt_id;
 
            let mut last_end_if_stmt_id = end_if_stmt_id;
 
            let mut last_parent_scope_id = outer_scope_id;
 
            let mut last_relative_pos = transformed_stmts.len() as i32 + 1;
 
            transformed_stmts.push(last_if_stmt_id.upcast());
 

	
 
            for case_index in 1..total_num_cases {
 
                let (if_stmt_id, end_if_stmt_id, scope_id) = transform_select_case_code(ctx, self.current_procedure_id, id, case_index, select_variable_id, select_variable_type);
 
                let false_case_scope_id = ctx.heap.alloc_scope(|this| Scope::new(this, ScopeAssociation::If(last_if_stmt_id, false)));
 
                link_existing_child_to_new_parent_scope(ctx, &mut self.scope_buffer, false_case_scope_id, scope_id, 0);
 
                link_new_child_to_existing_parent_scope(ctx, &mut self.scope_buffer, last_parent_scope_id, false_case_scope_id, last_relative_pos);
 
                set_ast_if_statement_false_body(ctx, last_if_stmt_id, last_end_if_stmt_id, IfStatementCase{ body: if_stmt_id.upcast(), scope: false_case_scope_id });
 

	
 
                let end_if_stmt = &mut ctx.heap[end_if_stmt_id];
 
                end_if_stmt.next = last_end_if_stmt_id.upcast();
 

	
 
                last_if_stmt_id = if_stmt_id;
 
                last_end_if_stmt_id = end_if_stmt_id;
 
                last_parent_scope_id = false_case_scope_id;
 
                last_relative_pos = 0;
 
            }
 
        }
 

	
 
        // Final steps: set the statements of the replacement block statement,
 
        // link all of those statements together, and update the scopes.
 
        let first_stmt_id = transformed_stmts[0];
 
        let mut last_stmt_id = transformed_stmts[0];
 
        for stmt_id in transformed_stmts.iter().skip(1).copied() {
 
            set_ast_statement_next(ctx, last_stmt_id, stmt_id);
 
            last_stmt_id = stmt_id;
 
        }
 

	
 
        if total_num_cases == 0 {
 
            // If we don't have any cases, then we didn't connect the statements
 
            // up to the end of the outer block, so do that here
 
            set_ast_statement_next(ctx, last_stmt_id, outer_end_block_id.upcast());
 
        }
 

	
 
        let outer_block_stmt = &mut ctx.heap[outer_block_id];
 
        outer_block_stmt.next = first_stmt_id;
 
        outer_block_stmt.statements = transformed_stmts;
 

	
 
        return Ok(())
 
    }
 
}
 

	
 
// -----------------------------------------------------------------------------
 
// Utilities to create compiler-generated AST nodes
 
// -----------------------------------------------------------------------------
 

	
 
#[derive(Clone, Copy)]
 
enum TypeIdReference {
 
    DirectTypeId(TypeId),
 
    IndirectSameAsExpr(i32), // by type index
 
}
 

	
 
fn create_ast_variable(ctx: &mut Ctx, scope_id: ScopeId) -> VariableId {
 
    let variable_id = ctx.heap.alloc_variable(|this| Variable{
 
        this,
 
        kind: VariableKind::Local,
 
        parser_type: ParserType{
 
            elements: Vec::new(),
 
            full_span: InputSpan::new(),
 
        },
 
        identifier: Identifier::new_empty(InputSpan::new()),
 
        relative_pos_in_parent: -1,
 
        unique_id_in_scope: -1,
 
    });
 
    let scope = &mut ctx.heap[scope_id];
 
    scope.variables.push(variable_id);
 

	
 
    return variable_id;
 
}
 

	
 
fn create_ast_variable_expr(ctx: &mut Ctx, containing_procedure_id: ProcedureDefinitionId, variable_id: VariableId, variable_type_id: TypeIdReference) -> VariableExpressionId {
 
    let variable_type_index = add_new_procedure_expression_type(ctx, containing_procedure_id, variable_type_id);
 
    return ctx.heap.alloc_variable_expression(|this| VariableExpression{
 
        this,
 
        identifier: Identifier::new_empty(InputSpan::new()),
 
        declaration: Some(variable_id),
 
        used_as_binding_target: false,
 
        parent: ExpressionParent::None,
 
        type_index: variable_type_index,
 
    });
 
}
 

	
 
/// Creates an AST call expression. The provided expression span is useful for
 
/// the cases where we perform compiler-builtin function calls that, when they
 
/// fail, should provide an error pointing at a specific point in the source
 
/// code. The `containing_procedure_id` is the procedure whose instructions are
 
/// going to contain this new call expression.
 
fn create_ast_call_expr(ctx: &mut Ctx, span: InputSpan, containing_procedure_id: ProcedureDefinitionId, method: Method, buffer: &mut ScopedBuffer<ExpressionId>, arguments: Vec<ExpressionId>) -> CallExpressionId {
 
    let call_type_id = match method {
 
        Method::SelectStart => ctx.arch.void_type_id,
 
        Method::SelectRegisterCasePort => ctx.arch.void_type_id,
 
        Method::SelectWait => ctx.arch.uint32_type_id, // TODO: Not pretty, this. Pretty error prone
 
        _ => unreachable!(), // if this goes of, add the appropriate method here.
 
    };
 

	
 
    let expression_ids = buffer.start_section_initialized(&arguments);
 
    let call_type_index = add_new_procedure_expression_type(ctx, containing_procedure_id, TypeIdReference::DirectTypeId(call_type_id));
 
    let call_expression_id = ctx.heap.alloc_call_expression(|this| CallExpression{
 
        func_span: InputSpan::new(),
 
        this,
 
        full_span: span,
 
        parser_type: ParserType{
 
            elements: Vec::new(),
 
            full_span: InputSpan::new(),
 
        },
 
        method,
 
        arguments,
 
        procedure: ProcedureDefinitionId::new_invalid(),
 
        parent: ExpressionParent::None,
 
        type_index: call_type_index,
 
    });
 

	
 
    for argument_index in 0..expression_ids.len() {
 
        let argument_id = expression_ids[argument_index];
 
        let argument_expr = &mut ctx.heap[argument_id];
 
        *argument_expr.parent_mut() = ExpressionParent::Expression(call_expression_id.upcast(), argument_index as u32);
 
    }
 

	
 
    return call_expression_id;
 
}
 

	
 
fn create_ast_literal_integer_expr(ctx: &mut Ctx, containing_procedure_id: ProcedureDefinitionId, unsigned_value: u64, type_id: TypeId) -> LiteralExpressionId {
 
    let literal_type_index = add_new_procedure_expression_type(ctx, containing_procedure_id, TypeIdReference::DirectTypeId(type_id));
 
    return ctx.heap.alloc_literal_expression(|this| LiteralExpression{
 
        this,
 
        span: InputSpan::new(),
 
        value: Literal::Integer(LiteralInteger{
 
            unsigned_value,
 
            negated: false,
 
        }),
 
        parent: ExpressionParent::None,
 
        type_index: literal_type_index,
 
    });
 
}
 

	
 
fn create_ast_equality_comparison_expr(
 
    ctx: &mut Ctx, containing_procedure_id: ProcedureDefinitionId,
 
    variable_id: VariableId, variable_type: TypeIdReference, value: u64
 
) -> BinaryExpressionId {
 
    let var_expr_id = create_ast_variable_expr(ctx, containing_procedure_id, variable_id, variable_type);
 
    let int_expr_id = create_ast_literal_integer_expr(ctx, containing_procedure_id, value, ctx.arch.uint32_type_id);
 
    let cmp_type_index = add_new_procedure_expression_type(ctx, containing_procedure_id, TypeIdReference::DirectTypeId(ctx.arch.bool_type_id));
 
    let cmp_expr_id = ctx.heap.alloc_binary_expression(|this| BinaryExpression{
 
        this,
 
        operator_span: InputSpan::new(),
 
        full_span: InputSpan::new(),
 
        left: var_expr_id.upcast(),
 
        operation: BinaryOperator::Equality,
 
        right: int_expr_id.upcast(),
 
        parent: ExpressionParent::None,
 
        type_index: cmp_type_index,
 
    });
 

	
 
    let var_expr = &mut ctx.heap[var_expr_id];
 
    var_expr.parent = ExpressionParent::Expression(cmp_expr_id.upcast(), 0);
 
    let int_expr = &mut ctx.heap[int_expr_id];
 
    int_expr.parent = ExpressionParent::Expression(cmp_expr_id.upcast(), 1);
 

	
 
    return cmp_expr_id;
 
}
 

	
 
fn create_ast_expression_stmt(ctx: &mut Ctx, expression_id: ExpressionId) -> ExpressionStatementId {
 
    let statement_id = ctx.heap.alloc_expression_statement(|this| ExpressionStatement{
 
        this,
 
        span: InputSpan::new(),
 
        expression: expression_id,
 
        next: StatementId::new_invalid(),
 
    });
 

	
 
    let expression = &mut ctx.heap[expression_id];
 
    *expression.parent_mut() = ExpressionParent::ExpressionStmt(statement_id);
 

	
 
    return statement_id;
 
}
 

	
 
fn create_ast_variable_declaration_stmt(
 
    ctx: &mut Ctx, containing_procedure_id: ProcedureDefinitionId,
 
    variable_id: VariableId, variable_type: TypeIdReference, initial_value_expr_id: ExpressionId
 
) -> MemoryStatementId {
 
    // Create the assignment expression, assigning the initial value to the variable
 
    let variable_expr_id = create_ast_variable_expr(ctx, containing_procedure_id, variable_id, variable_type);
 
    let void_type_index = add_new_procedure_expression_type(ctx, containing_procedure_id, TypeIdReference::DirectTypeId(ctx.arch.void_type_id));
 
    let assignment_expr_id = ctx.heap.alloc_assignment_expression(|this| AssignmentExpression{
 
        this,
 
        operator_span: InputSpan::new(),
 
        full_span: InputSpan::new(),
 
        left: variable_expr_id.upcast(),
 
        operation: AssignmentOperator::Set,
 
        right: initial_value_expr_id,
 
        parent: ExpressionParent::None,
 
        type_index: void_type_index,
 
    });
 

	
 
    // Create the memory statement
 
    let memory_stmt_id = ctx.heap.alloc_memory_statement(|this| MemoryStatement{
 
        this,
 
        span: InputSpan::new(),
 
        variable: variable_id,
 
        initial_expr: assignment_expr_id,
 
        next: StatementId::new_invalid(),
 
    });
 

	
 
    // Set all parents which we can access
 
    let variable_expr = &mut ctx.heap[variable_expr_id];
 
    variable_expr.parent = ExpressionParent::Expression(assignment_expr_id.upcast(), 0);
 
    let value_expr = &mut ctx.heap[initial_value_expr_id];
 
    *value_expr.parent_mut() = ExpressionParent::Expression(assignment_expr_id.upcast(), 1);
 
    let assignment_expr = &mut ctx.heap[assignment_expr_id];
 
    assignment_expr.parent = ExpressionParent::Memory(memory_stmt_id);
 

	
 
    return memory_stmt_id;
 
}
 

	
 
fn create_ast_block_stmt(ctx: &mut Ctx, statements: Vec<StatementId>) -> (BlockStatementId, EndBlockStatementId, ScopeId) {
 
    let block_stmt_id = ctx.heap.alloc_block_statement(|this| BlockStatement{
 
        this,
 
        span: InputSpan::new(),
 
        statements,
 
        end_block: EndBlockStatementId::new_invalid(),
 
        scope: ScopeId::new_invalid(),
 
        next: StatementId::new_invalid(),
 
    });
 
    let end_block_stmt_id = ctx.heap.alloc_end_block_statement(|this| EndBlockStatement{
 
        this,
 
        start_block: block_stmt_id,
 
        next: StatementId::new_invalid(),
 
    });
 
    let scope_id = ctx.heap.alloc_scope(|this| Scope::new(this, ScopeAssociation::Block(block_stmt_id)));
 

	
 
    let block_stmt = &mut ctx.heap[block_stmt_id];
 
    block_stmt.end_block = end_block_stmt_id;
 
    block_stmt.scope = scope_id;
 

	
 
    return (block_stmt_id, end_block_stmt_id, scope_id);
 
}
 

	
 
fn create_ast_if_stmt(ctx: &mut Ctx, condition_expression_id: ExpressionId, true_case: IfStatementCase, false_case: Option<IfStatementCase>) -> (IfStatementId, EndIfStatementId) {
 
    // Create if statement and the end-if statement
 
    let if_stmt_id = ctx.heap.alloc_if_statement(|this| IfStatement{
 
        this,
 
        span: InputSpan::new(),
 
        test: condition_expression_id,
 
        true_case,
 
        false_case,
 
        end_if: EndIfStatementId::new_invalid()
 
    });
 

	
 
    let end_if_stmt_id = ctx.heap.alloc_end_if_statement(|this| EndIfStatement{
 
        this,
 
        start_if: if_stmt_id,
 
        next: StatementId::new_invalid(),
 
    });
 

	
 
    // Link the statements up as much as we can
 
    let if_stmt = &mut ctx.heap[if_stmt_id];
 
    if_stmt.end_if = end_if_stmt_id;
 

	
 
    let condition_expr = &mut ctx.heap[condition_expression_id];
 
    *condition_expr.parent_mut() = ExpressionParent::If(if_stmt_id);
 

	
 

	
 

	
 
    return (if_stmt_id, end_if_stmt_id);
 
}
 

	
 
/// Sets the false body for a given
 
fn set_ast_if_statement_false_body(ctx: &mut Ctx, if_statement_id: IfStatementId, end_if_statement_id: EndIfStatementId, false_case: IfStatementCase) {
 
    // Point if-statement to "false body"
 
    let if_stmt = &mut ctx.heap[if_statement_id];
 
    debug_assert!(if_stmt.false_case.is_none()); // simplifies logic, not necessary
 
    if_stmt.false_case = Some(false_case);
 

	
 
    // Point end of false body to the end of the if statement
 
    set_ast_statement_next(ctx, false_case.body, end_if_statement_id.upcast());
 
}
 

	
 
/// Sets the specified AST statement's control flow such that it will be
 
/// followed by the target statement. This may seem obvious, but may imply that
 
/// a statement associated with, but different from, the source statement is
 
/// modified.
 
fn set_ast_statement_next(ctx: &mut Ctx, source_stmt_id: StatementId, target_stmt_id: StatementId) {
 
    let source_stmt = &mut ctx.heap[source_stmt_id];
 
    match source_stmt {
 
        Statement::Block(stmt) => {
 
            let end_id = stmt.end_block;
 
            ctx.heap[end_id].next = target_stmt_id
 
        },
 
        Statement::EndBlock(stmt) => stmt.next = target_stmt_id,
 
        Statement::Local(stmt) => {
 
            match stmt {
 
                LocalStatement::Memory(stmt) => stmt.next = target_stmt_id,
 
                LocalStatement::Channel(stmt) => stmt.next = target_stmt_id,
 
            }
 
        },
 
        Statement::Labeled(stmt) => {
 
            let body_id = stmt.body;
 
            set_ast_statement_next(ctx, body_id, target_stmt_id);
 
        },
 
        Statement::If(stmt) => {
 
            let end_id = stmt.end_if;
 
            ctx.heap[end_id].next = target_stmt_id;
 
        },
 
        Statement::EndIf(stmt) => stmt.next = target_stmt_id,
 
        Statement::While(stmt) => {
 
            let end_id = stmt.end_while;
 
            ctx.heap[end_id].next = target_stmt_id;
 
        },
 
        Statement::EndWhile(stmt) => stmt.next = target_stmt_id,
 

	
 
        Statement::Break(_stmt) => {},
 
        Statement::Continue(_stmt) => {},
 
        Statement::Synchronous(stmt) => {
 
            let end_id = stmt.end_sync;
 
            ctx.heap[end_id].next = target_stmt_id;
 
        },
 
        Statement::EndSynchronous(stmt) => {
 
            stmt.next = target_stmt_id;
 
        },
 
        Statement::Fork(_) | Statement::EndFork(_) => {
 
            todo!("remove fork from language");
 
        },
 
        Statement::Select(stmt) => {
 
            let end_id = stmt.end_select;
 
            ctx.heap[end_id].next = target_stmt_id;
 
        },
 
        Statement::EndSelect(stmt) => stmt.next = target_stmt_id,
 
        Statement::Return(_stmt) => {},
 
        Statement::Goto(_stmt) => {},
 
        Statement::New(stmt) => stmt.next = target_stmt_id,
 
        Statement::Expression(stmt) => stmt.next = target_stmt_id,
 
    }
 
}
 

	
 
/// Links a new scope to an existing scope as its child.
 
fn link_new_child_to_existing_parent_scope(ctx: &mut Ctx, scope_buffer: &mut ScopedBuffer<ScopeId>, parent_scope_id: ScopeId, child_scope_id: ScopeId, relative_pos_hint: i32) {
src/runtime2/component/component.rs
Show inline comments
 
use std::fmt::{Display as FmtDisplay, Result as FmtResult, Formatter};
 

	
 
use crate::protocol::eval::{Prompt, EvalError, ValueGroup, PortId as EvalPortId};
 
use crate::protocol::*;
 
use crate::runtime2::*;
 
use crate::runtime2::communication::*;
 

	
 
use super::{CompCtx, CompPDL, CompId};
 
use super::component_context::*;
 
use super::component_random::*;
 
use super::component_internet::*;
 
use super::control_layer::*;
 
use super::consensus::*;
 

	
 
pub enum CompScheduling {
 
    Immediate,
 
    Requeue,
 
    Sleep,
 
    Exit,
 
}
 

	
 
/// Potential error emitted by a component
 
pub enum CompError {
 
    /// Error originating from the code executor. Hence has an associated
 
    /// source location.
 
    Executor(EvalError),
 
    /// Error originating from a component, but not necessarily associated with
 
    /// a location in the source.
 
    Component(String), // TODO: Maybe a different embedded value in the future?
 
    /// Pure runtime error. Not necessarily originating from the component
 
    /// itself. Should be treated as a very severe runtime-compromising error.
 
    Runtime(RtError),
 
}
 

	
 
impl FmtDisplay for CompError {
 
    fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
 
        match self {
 
            CompError::Executor(v) => v.fmt(f),
 
            CompError::Component(v) => v.fmt(f),
 
            CompError::Runtime(v) => v.fmt(f),
 
        }
 
    }
 
}
 

	
 
/// Generic representation of a component (as viewed by a scheduler).
 
pub(crate) trait Component {
 
    /// Called upon the creation of the component. Note that the scheduler
 
    /// context is officially running another component (the component that is
 
    /// creating the new component).
 
    fn on_creation(&mut self, comp_id: CompId, sched_ctx: &SchedulerCtx);
 

	
 
    /// Called when a component crashes or wishes to exit. So is not called
 
    /// right before destruction, other components may still hold a handle to
 
    /// the component and send it messages!
 
    fn on_shutdown(&mut self, sched_ctx: &SchedulerCtx);
 

	
 
    /// Called if the component is created by another component and the messages
 
    /// are being transferred between the two.
 
    fn adopt_message(&mut self, comp_ctx: &mut CompCtx, message: DataMessage);
 

	
 
    /// Called if the component receives a new message. The component is
 
    /// responsible for deciding where that messages goes.
 
    fn handle_message(&mut self, sched_ctx: &mut SchedulerCtx, comp_ctx: &mut CompCtx, message: Message);
 

	
 
    /// Called if the component's routine should be executed. The return value
 
    /// can be used to indicate when the routine should be run again.
 
    fn run(&mut self, sched_ctx: &mut SchedulerCtx, comp_ctx: &mut CompCtx) -> CompScheduling;
 
}
 

	
 
/// Representation of the generic operating mode of a component.
 
/// Representation of the generic operating mode of a component. Although not
 
/// every state may be used by every kind of (builtin) component, this allows
 
/// writing standard handlers for particular events in a component's lifetime.
 
#[derive(Debug, Copy, Clone, PartialEq, Eq)]
 
pub(crate) enum CompMode {
 
    NonSync, // not in sync mode
 
    Sync, // in sync mode, can interact with other components
 
    SyncEnd, // awaiting a solution, i.e. encountered the end of the sync block
 
    BlockedGet, // blocked because we need to receive a message on a particular port
 
    BlockedPut, // component is blocked because the port is blocked
 
    BlockedSelect, // waiting on message to complete the select statement
 
    StartExit, // temporary state: if encountered then we start the shutdown process.
 
    BusyExit, // temporary state: waiting for Acks for all the closed ports, potentially waiting for sync round to finish
 
    Exit, // exiting: shutdown process started, now waiting until the reference count drops to 0
 
}
 

	
 
impl CompMode {
 
    pub(crate) fn is_in_sync_block(&self) -> bool {
 
        use CompMode::*;
 

	
 
        match self {
 
            Sync | SyncEnd | BlockedGet | BlockedPut | BlockedSelect => true,
 
            NonSync | StartExit | BusyExit | Exit => false,
 
        }
 
    }
 

	
 
    pub(crate) fn is_busy_exiting(&self) -> bool {
 
        use CompMode::*;
 

	
 
        match self {
 
            NonSync | Sync | SyncEnd | BlockedGet | BlockedPut | BlockedSelect => false,
 
            StartExit | BusyExit => true,
 
            Exit => false,
 
        }
 
    }
 
}
 

	
 
#[derive(Debug)]
 
pub(crate) enum ExitReason {
 
    Termination, // regular termination of component
 
    ErrorInSync,
 
    ErrorNonSync,
 
}
 

	
 
impl ExitReason {
 
    pub(crate) fn is_in_sync(&self) -> bool {
 
        use ExitReason::*;
 

	
 
        match self {
 
            Termination | ErrorNonSync => false,
 
            ErrorInSync => true,
 
        }
 
    }
 

	
 
    pub(crate) fn is_error(&self) -> bool {
 
        use ExitReason::*;
 

	
 
        match self {
 
            Termination => false,
 
            ErrorInSync | ErrorNonSync => true,
 
        }
 
    }
 
}
 

	
 
/// Component execution state: the execution mode along with some descriptive
 
/// fields. Fields are public for ergonomic reasons, use member functions when
 
/// appropriate.
 
pub(crate) struct CompExecState {
 
    pub mode: CompMode,
 
    pub mode_port: PortId, // valid if blocked on a port (put/get)
 
    pub mode_value: ValueGroup, // valid if blocked on a put
 
    pub exit_reason: ExitReason, // valid if in StartExit/BusyExit/Exit mode
 
}
 

	
 
impl CompExecState {
 
    pub(crate) fn new() -> Self {
 
        return Self{
 
            mode: CompMode::NonSync,
 
            mode_port: PortId::new_invalid(),
 
            mode_value: ValueGroup::default(),
 
            exit_reason: ExitReason::Termination,
 
        }
 
    }
 

	
 
    pub(crate) fn set_as_start_exit(&mut self, reason: ExitReason) {
 
        self.mode = CompMode::StartExit;
 
        self.exit_reason = reason;
 
    }
 

	
 
    pub(crate) fn set_as_blocked_get(&mut self, port: PortId) {
 
        self.mode = CompMode::BlockedGet;
 
        self.mode_port = port;
 
        debug_assert!(self.mode_value.values.is_empty());
 
    }
 

	
 
    pub(crate) fn is_blocked_on_get(&self, port: PortId) -> bool {
 
        return
 
            self.mode == CompMode::BlockedGet &&
 
            self.mode_port == port;
 
    }
 

	
 
    pub(crate) fn set_as_blocked_put(&mut self, port: PortId, value: ValueGroup) {
 
        self.mode = CompMode::BlockedPut;
 
        self.mode_port = port;
 
        self.mode_value = value;
 
    }
 

	
 
    pub(crate) fn is_blocked_on_put(&self, port: PortId) -> bool {
 
        return
 
            self.mode == CompMode::BlockedPut &&
 
            self.mode_port == port;
 
    }
 
}
 

	
 
/// Generic representation of a component's inbox.
 
// NOTE: It would be nice to remove the `backup` at some point and make the
 
// blocking occur the moment a peer tries to send a message.
 
pub(crate) struct CompInbox {
 
    main: Vec<Option<DataMessage>>,
 
    backup: Vec<DataMessage>,
 
}
 

	
 
/// Creates a new component based on its definition. Meaning that if it is a
 
/// user-defined component then we set up the PDL code state. Otherwise we
 
/// construct a custom component. This does NOT take care of port and message
 
/// management.
 
pub(crate) fn create_component(
 
    protocol: &ProtocolDescription,
 
    definition_id: ProcedureDefinitionId, type_id: TypeId,
 
    arguments: ValueGroup, num_ports: usize
 
) -> Box<dyn Component> {
 
    let definition = &protocol.heap[definition_id];
 
    debug_assert!(definition.kind == ProcedureKind::Primitive || definition.kind == ProcedureKind::Composite);
 

	
 
    if definition.source.is_builtin() {
 
        // Builtin component
 
        let component: Box<dyn Component> = match definition.source {
 
            ProcedureSource::CompRandomU32 => Box::new(ComponentRandomU32::new(arguments)),
 
            ProcedureSource::CompTcpClient => Box::new(ComponentTcpClient::new(arguments)),
 
            _ => unreachable!(),
 
        };
 

	
 
        return component;
 
    } else {
 
        // User-defined component
 
        let prompt = Prompt::new(
 
            &protocol.types, &protocol.heap,
 
            definition_id, type_id, arguments
 
        );
 
        let component = CompPDL::new(prompt, num_ports);
 
        return Box::new(component);
 
    }
 
}
 

	
 
// -----------------------------------------------------------------------------
 
// Generic component messaging utilities (for sending and receiving)
 
// -----------------------------------------------------------------------------
 

	
 
/// Default handling of sending a data message. In case the port is blocked then
 
/// the `ExecState` will become blocked as well. Note that
 
/// `default_handle_control_message` will ensure that the port becomes
 
/// unblocked if so instructed by the receiving component. The returned
 
/// scheduling value must be used.
 
#[must_use]
 
pub(crate) fn default_send_data_message(
 
    exec_state: &mut CompExecState, transmitting_port_id: PortId,
 
    port_instruction: PortInstruction, value: ValueGroup,
 
    sched_ctx: &SchedulerCtx, consensus: &mut Consensus, comp_ctx: &mut CompCtx
 
) -> Result<CompScheduling, (PortInstruction, String)> {
 
    debug_assert_eq!(exec_state.mode, CompMode::Sync);
 

	
 
    let port_handle = comp_ctx.get_port_handle(transmitting_port_id);
 
    let port_info = comp_ctx.get_port_mut(port_handle);
 
    port_info.last_instruction = port_instruction;
 

	
 
    let port_info = comp_ctx.get_port(port_handle);
 
    debug_assert_eq!(port_info.kind, PortKind::Putter);
 

	
 
    if port_info.state == PortState::Closed {
 
        // Note: normally peer is eventually consistent, but if it has shut down
 
        // then we can be sure it is consistent (I think?)
 
        return Err((
 
            port_info.last_instruction,
 
            format!("Cannot send on this port, as the peer (id:{}) has shut down", port_info.peer_comp_id.0)
 
        ))
 
    } else if port_info.state.is_blocked() {
 
        // Port is blocked, so we cannot send
 
        exec_state.set_as_blocked_put(transmitting_port_id, value);
 

	
 
        return Ok(CompScheduling::Sleep);
 
    } else {
 
        // Port is not blocked, so send to the peer
 
        let peer_handle = comp_ctx.get_peer_handle(port_info.peer_comp_id);
 
        let peer_info = comp_ctx.get_peer(peer_handle);
 
        let annotated_message = consensus.annotate_data_message(comp_ctx, port_info, value);
 
        peer_info.handle.send_message(&sched_ctx.runtime, Message::Data(annotated_message), true);
 

	
 
        return Ok(CompScheduling::Immediate);
 
    }
 
}
 

	
 
pub(crate) enum IncomingData {
 
    PlacedInSlot,
 
    SlotFull(DataMessage),
 
}
 

	
 
/// Default handling of receiving a data message. In case there is no room for
 
/// the message it is returned from this function. Note that this function is
 
/// different from PDL code performing a `get` on a port; this is the case where
 
/// the message first arrives at the component.
 
// NOTE: This is supposed to be a somewhat temporary implementation. It would be
 
//  nicest if the sending component can figure out it cannot send any more data.
 
#[must_use]
 
pub(crate) fn default_handle_incoming_data_message(
 
    exec_state: &mut CompExecState, port_value_slot: &mut Option<DataMessage>,
 
    comp_ctx: &mut CompCtx, incoming_message: DataMessage,
 
    sched_ctx: &SchedulerCtx, control: &mut ControlLayer
 
) -> IncomingData {
 
    let target_port_id = incoming_message.data_header.target_port;
 

	
 
    if port_value_slot.is_none() {
 
        // We can put the value in the slot
 
        *port_value_slot = Some(incoming_message);
 

	
 
        // Check if we're blocked on receiving this message.
 
        dbg_code!({
 
            // Our port cannot have been blocked itself, because we're able to
 
            // directly insert the message into its slot.
 
            let port_handle = comp_ctx.get_port_handle(target_port_id);
 
            assert!(!comp_ctx.get_port(port_handle).state.is_blocked());
 
        });
 

	
 
        if exec_state.is_blocked_on_get(target_port_id) {
 
            // Return to normal operation
 
            exec_state.mode = CompMode::Sync;
 
            exec_state.mode_port = PortId::new_invalid();
 
            debug_assert!(exec_state.mode_value.values.is_empty());
 
        }
 

	
 
        return IncomingData::PlacedInSlot
 
    } else {
 
        // Slot is already full, so if the port was previously opened, it will
 
        // now become closed
 
        let port_handle = comp_ctx.get_port_handle(target_port_id);
 
        let port_info = comp_ctx.get_port_mut(port_handle);
 
        debug_assert!(port_info.state == PortState::Open || port_info.state.is_blocked()); // i.e. not closed, but will go off if more states are added in the future
 

	
 
        if port_info.state == PortState::Open {
 
            comp_ctx.set_port_state(port_handle, PortState::BlockedDueToFullBuffers);
 
            let (peer_handle, message) =
 
                control.initiate_port_blocking(comp_ctx, port_handle);
 
            let peer = comp_ctx.get_peer(peer_handle);
 
            peer.handle.send_message(&sched_ctx.runtime, Message::Control(message), true);
 
        }
 

	
 
        return IncomingData::SlotFull(incoming_message)
 
    }
 
}
 

	
 
/// Default handling that has been received through a `get`. Will check if any
 
/// more messages are waiting, and if the corresponding port was blocked because
 
/// of full buffers (hence, will use the control layer to make sure the peer
 
/// will become unblocked).
 
pub(crate) fn default_handle_received_data_message(
 
    targeted_port: PortId, port_instruction: PortInstruction,
 
    slot: &mut Option<DataMessage>, inbox_backup: &mut Vec<DataMessage>,
 
    comp_ctx: &mut CompCtx, sched_ctx: &SchedulerCtx, control: &mut ControlLayer
 
) -> Result<(), (PortInstruction, String)> {
 
    debug_assert!(slot.is_none()); // because we've just received from it
 

	
 
    // Modify last-known location where port instruction was retrieved
 
    let port_handle = comp_ctx.get_port_handle(targeted_port);
 
    let port_info = comp_ctx.get_port_mut(port_handle);
 
    port_info.last_instruction = port_instruction;
 

	
 
    if port_info.state == PortState::Closed {
 
        return Err((
 
            port_info.last_instruction,
 
            format!("Cannot 'get' because the channel is closed"))
 
        );
 
    }
 

	
 
    // Check if there are any more messages in the backup buffer
 
    let port_info = comp_ctx.get_port(port_handle);
 
    for message_index in 0..inbox_backup.len() {
 
        let message = &inbox_backup[message_index];
 
        if message.data_header.target_port == targeted_port {
 
            // One more message, place it in the slot
 
            let message = inbox_backup.remove(message_index);
 
            debug_assert!(port_info.state.is_blocked()); // since we're removing another message from the backup
 
            *slot = Some(message);
 

	
 
            return Ok(());
 
        }
 
    }
 

	
 
    // Did not have any more messages, so if we were blocked, then we need to
 
    // unblock the port now (and inform the peer of this unblocking)
 
    if port_info.state == PortState::BlockedDueToFullBuffers {
 
        comp_ctx.set_port_state(port_handle, PortState::Open);
 
        let (peer_handle, message) = control.cancel_port_blocking(comp_ctx, port_handle);
 
        let peer_info = comp_ctx.get_peer(peer_handle);
 
        peer_info.handle.send_message(&sched_ctx.runtime, Message::Control(message), true);
 
    }
 

	
 
    return Ok(());
 
}
 

	
 
/// Handles control messages in the default way. Note that this function may
 
/// take a lot of actions in the name of the caller: pending messages may be
 
/// sent, ports may become blocked/unblocked, etc. So the execution
 
/// (`CompExecState`), control (`ControlLayer`) and consensus (`Consensus`)
 
/// state may all change.
 
pub(crate) fn default_handle_control_message(
 
    exec_state: &mut CompExecState, control: &mut ControlLayer, consensus: &mut Consensus,
 
    message: ControlMessage, sched_ctx: &SchedulerCtx, comp_ctx: &mut CompCtx
 
) -> Result<(), (PortInstruction, String)> {
 
    match message.content {
 
        ControlMessageContent::Ack => {
 
            default_handle_ack(control, message.id, sched_ctx, comp_ctx);
 
        },
 
        ControlMessageContent::BlockPort(port_id) => {
 
            // One of our messages was accepted, but the port should be
 
            // blocked.
 
            let port_handle = comp_ctx.get_port_handle(port_id);
 
            let port_info = comp_ctx.get_port(port_handle);
 
            debug_assert_eq!(port_info.kind, PortKind::Putter);
 
            if port_info.state == PortState::Open {
 
                // only when open: we don't do this when closed, and we we don't do this if we're blocked due to peer changes
 
                comp_ctx.set_port_state(port_handle, PortState::BlockedDueToFullBuffers);
 
            }
 
        },
 
        ControlMessageContent::ClosePort(content) => {
 
            // Request to close the port. We immediately comply and remove
 
            // the component handle as well
 
            let port_handle = comp_ctx.get_port_handle(content.port_to_close);
 

	
 
            // We're closing the port, so we will always update the peer of the
 
            // port (in case of error messages)
 
            let port_info = comp_ctx.get_port_mut(port_handle);
 
            port_info.peer_comp_id = message.sender_comp_id;
 
            port_info.close_at_sync_end = true; // might be redundant (we might set it closed now)
 

	
 
            let port_info = comp_ctx.get_port(port_handle);
 
            let peer_comp_id = port_info.peer_comp_id;
 
            let peer_handle = comp_ctx.get_peer_handle(peer_comp_id);
 

	
 
            // One exception to sending an `Ack` is if we just closed the
 
            // port ourselves, meaning that the `ClosePort` messages got
 
            // sent to one another.
 
            if let Some(control_id) = control.has_close_port_entry(port_handle, comp_ctx) {
 
                // The two components (sender and this component) are closing
 
                // the channel at the same time.
 
                // the channel at the same time. So we don't care about the
 
                // content of the `ClosePort` message.
 
                default_handle_ack(control, control_id, sched_ctx, comp_ctx);
 
            } else {
 
                // Respond to the message
 
                let last_instruction = port_info.last_instruction;
 
                let port_was_used = last_instruction != PortInstruction::None;
 
                let port_has_had_message = port_info.received_message_for_sync;
 
                default_send_ack(message.id, peer_handle, sched_ctx, comp_ctx);
 
                comp_ctx.remove_peer(sched_ctx, port_handle, peer_comp_id, false); // do not remove if closed
 
                comp_ctx.set_port_state(port_handle, PortState::Closed); // now set to closed
 

	
 
                // Make sure that we've not reached an error condition. Note
 
                // that if this condition is not met, then we don't error out
 
                // now, but we may error out in the next sync block when we
 
                // try to `put`/`get` on the port. This condition makes sure
 
                // that if we have a successful sync round, followed by the peer
 
                // closing the port, that we don't consider the sync round to
 
                // have failed by mistake.
 
                if content.closed_in_sync_round && exec_state.mode.is_in_sync_block() && port_was_used {
 
                    return Err((
 
                        last_instruction,
 
                        format!("Peer component (id:{}) shut down, so previous communication cannot have succeeded", peer_comp_id.0)
 
                    ));
 

	
 
                // Handle any possible error conditions (which boil down to: the
 
                // port has been used, but the peer has died). If not in sync
 
                // mode then we close the port immediately.
 

	
 
                // Note that `port_was_used` does not mean that any messages
 
                // were actually received. It might also mean that e.g. the
 
                // component attempted a `get`, but there were no messages, so
 
                // now it is in the `BlockedGet` state.
 
                let port_was_used = last_instruction != PortInstruction::None;
 

	
 
                if exec_state.mode.is_in_sync_block() {
 
                    let closed_during_sync_round = content.closed_in_sync_round && port_was_used;
 
                    // TODO: Finish this
 

	
 
                    if closed_during_sync_round {
 
                        return Err((
 
                            last_instruction,
 
                            format!("Peer component (id:{}) shut down, so previous communication cannot have succeeded", peer_comp_id.0)
 
                        ));
 
                    }
 
                } else {
 
                    comp_ctx.set_port_state(port_handle, PortState::Closed);
 
                }
 
            }
 
        },
 
        ControlMessageContent::UnblockPort(port_id) => {
 
            // We were previously blocked (or already closed)
 
            let port_handle = comp_ctx.get_port_handle(port_id);
 
            let port_info = comp_ctx.get_port(port_handle);
 
            debug_assert_eq!(port_info.kind, PortKind::Putter);
 
            if port_info.state == PortState::BlockedDueToFullBuffers {
 
                default_handle_unblock_put(exec_state, consensus, port_handle, sched_ctx, comp_ctx);
 
            }
 
        },
 
        ControlMessageContent::PortPeerChangedBlock(port_id) => {
 
            // The peer of our port has just changed. So we are asked to
 
            // temporarily block the port (while our original recipient is
 
            // potentially rerouting some of the in-flight messages) and
 
            // Ack. Then we wait for the `unblock` call.
 
            debug_assert_eq!(message.target_port_id, Some(port_id));
 
            let port_handle = comp_ctx.get_port_handle(port_id);
 
            comp_ctx.set_port_state(port_handle, PortState::BlockedDueToPeerChange);
 

	
 
            let port_info = comp_ctx.get_port(port_handle);
 
            let peer_handle = comp_ctx.get_peer_handle(port_info.peer_comp_id);
 

	
 
            default_send_ack(message.id, peer_handle, sched_ctx, comp_ctx);
 
        },
 
        ControlMessageContent::PortPeerChangedUnblock(new_port_id, new_comp_id) => {
 
            let port_handle = comp_ctx.get_port_handle(message.target_port_id.unwrap());
 
            let port_info = comp_ctx.get_port(port_handle);
 
            debug_assert!(port_info.state == PortState::BlockedDueToPeerChange);
 
            let old_peer_id = port_info.peer_comp_id;
 

	
 
            comp_ctx.remove_peer(sched_ctx, port_handle, old_peer_id, false);
 

	
 
            let port_info = comp_ctx.get_port_mut(port_handle);
 
            port_info.peer_comp_id = new_comp_id;
 
            port_info.peer_port_id = new_port_id;
 
            comp_ctx.add_peer(port_handle, sched_ctx, new_comp_id, None);
 
            default_handle_unblock_put(exec_state, consensus, port_handle, sched_ctx, comp_ctx);
 
        }
 
    }
 

	
 
    return Ok(());
 
}
 

	
 
/// Handles a component entering the synchronous block. Will ensure that the
 
/// `Consensus` and the `ComponentCtx` are initialized properly.
 
pub(crate) fn default_handle_start_sync(
 
    exec_state: &mut CompExecState,
 
) {}
 

	
 
/// Handles a component initiating the exiting procedure, and closing all of its
 
/// ports. Should only be called once per component (which is ensured by
 
/// checking and modifying the mode in the execution state).
 
#[must_use]
 
pub(crate) fn default_handle_start_exit(
 
    exec_state: &mut CompExecState, control: &mut ControlLayer,
 
    sched_ctx: &SchedulerCtx, comp_ctx: &mut CompCtx, consensus: &mut Consensus
 
) -> CompScheduling {
 
    debug_assert_eq!(exec_state.mode, CompMode::StartExit);
 
    sched_ctx.log("Component starting exit");
 
    exec_state.mode = CompMode::BusyExit;
 
    let exit_inside_sync = exec_state.exit_reason.is_in_sync();
 

	
 
    // If exiting while inside sync mode, report to the leader of the current
 
    // round that we've failed.
 
    if exit_inside_sync {
 
        let decision = consensus.notify_sync_end_failure(sched_ctx, comp_ctx);
 
        default_handle_sync_decision(sched_ctx, exec_state, decision, consensus);
 
        default_handle_sync_decision(sched_ctx, exec_state, comp_ctx, decision, consensus);
 
    }
 

	
 
    // Iterating over ports by index to work around borrowing rules
 
    for port_index in 0..comp_ctx.num_ports() {
 
        let port = comp_ctx.get_port_by_index_mut(port_index);
 
        if port.state == PortState::Closed {
 
            // Already closed, or in the process of being closed
 
            continue;
 
        }
 

	
 
        // Mark as closed
 
        let port_id = port.self_id;
 
        port.state = PortState::Closed;
 

	
 
        // Notify peer of closing
 
        let port_handle = comp_ctx.get_port_handle(port_id);
 
        let (peer, message) = control.initiate_port_closing(port_handle, exit_inside_sync, comp_ctx);
 
        let peer_info = comp_ctx.get_peer(peer);
 
        peer_info.handle.send_message(&sched_ctx.runtime, Message::Control(message), true);
 
    }
 

	
 
    return CompScheduling::Immediate; // to check if we can shut down immediately
 
}
 

	
 
/// Handles a component waiting until all peers are notified that it is quitting
 
/// (i.e. after calling `default_handle_start_exit`).
 
#[must_use]
 
pub(crate) fn default_handle_busy_exit(
 
    exec_state: &mut CompExecState, control: &ControlLayer,
 
    sched_ctx: &SchedulerCtx
 
) -> CompScheduling {
 
    debug_assert_eq!(exec_state.mode, CompMode::BusyExit);
 
    if control.has_acks_remaining() {
 
        sched_ctx.log("Component busy exiting, still has `Ack`s remaining");
 
        return CompScheduling::Sleep;
 
    } else {
 
        sched_ctx.log("Component busy exiting, now shutting down");
 
        exec_state.mode = CompMode::Exit;
 
        return CompScheduling::Exit;
 
    }
 
}
 

	
 
/// Handles a potential synchronous round decision. If there was a decision then
 
/// the `Some(success)` value indicates whether the round succeeded or not.
 
/// Might also end up changing the `ExecState`.
 
///
 
/// Might be called in two cases:
 
/// 1. The component is in regular execution mode, at the end of a sync round,
 
///     and is waiting for a solution to the round.
 
/// 2. The component has encountered an error during a sync round and is
 
///     exiting, hence is waiting for a "Failure" message from the leader.
 
pub(crate) fn default_handle_sync_decision(
 
    sched_ctx: &SchedulerCtx, exec_state: &mut CompExecState, comp_ctx: &mut CompCtx,
 
    decision: SyncRoundDecision, consensus: &mut Consensus
 
) -> Option<bool> {
 
    let success = match decision {
 
        SyncRoundDecision::None => return None,
 
        SyncRoundDecision::Solution => true,
 
        SyncRoundDecision::Failure => false,
 
    };
 

	
 
    debug_assert!(
 
        exec_state.mode == CompMode::SyncEnd || (
 
            exec_state.mode.is_busy_exiting() && exec_state.exit_reason.is_error()
 
        ) || (
 
            exec_state.mode.is_in_sync_block() && decision == SyncRoundDecision::Failure
 
        )
 
    );
 

	
 
    sched_ctx.log(&format!("Handling decision {:?} (in mode: {:?})", decision, exec_state.mode));
 
    consensus.notify_sync_decision(decision);
 
    if success {
 
        // We cannot get a success message if the component has encountered an
 
        // error.
 
        for port_index in 0..comp_ctx.num_ports() {
 
            let port_info = comp_ctx.get_port_by_index_mut(port_index);
 
            if port_info.close_at_sync_end {
 
                port_info.state = PortState::Closed;
 
            }
 
        }
 
        debug_assert_eq!(exec_state.mode, CompMode::SyncEnd);
 
        exec_state.mode = CompMode::NonSync;
 
        return Some(true);
 
    } else {
 
        // We may get failure both in all possible cases. But we should only
 
        // modify the execution state if we're not already in exit mode
 
        if !exec_state.mode.is_busy_exiting() {
 
            sched_ctx.error("failed synchronous round, initiating exit");
 
            exec_state.set_as_start_exit(ExitReason::ErrorNonSync);
 
        }
 
        return Some(false);
 
    }
 
}
 

	
 
/// Performs the default action of printing the provided error, and then putting
 
/// the component in the state where it will shut down. Only to be used for
 
/// builtin components: their error message construction is simpler (and more
 
/// common) as they don't have any source code.
 
pub(crate) fn default_handle_error_for_builtin(
 
    exec_state: &mut CompExecState, sched_ctx: &SchedulerCtx,
 
    location_and_message: (PortInstruction, String)
 
) {
 
    let (_location, message) = location_and_message;
 
    sched_ctx.error(&message);
 

	
 
    let exit_reason = if exec_state.mode.is_in_sync_block() {
 
        ExitReason::ErrorInSync
 
    } else {
 
        ExitReason::ErrorNonSync
 
    };
 

	
 
    exec_state.set_as_start_exit(exit_reason);
 
}
 

	
 
#[inline]
 
pub(crate) fn default_handle_exit(_exec_state: &CompExecState) -> CompScheduling {
 
    debug_assert_eq!(_exec_state.mode, CompMode::Exit);
 
    return CompScheduling::Exit;
 
}
 

	
 
// -----------------------------------------------------------------------------
 
// Internal messaging/state utilities
 
// -----------------------------------------------------------------------------
 

	
 
/// Handles an `Ack` for the control layer.
 
fn default_handle_ack(
 
    control: &mut ControlLayer, control_id: ControlId,
 
    sched_ctx: &SchedulerCtx, comp_ctx: &mut CompCtx
 
) {
 
    // Since an `Ack` may cause another one, handle them in a loop
 
    let mut to_ack = control_id;
 
    loop {
 
        let (action, new_to_ack) = control.handle_ack(to_ack, sched_ctx, comp_ctx);
 
        match action {
 
            AckAction::SendMessage(target_comp, message) => {
 
                // FIX @NoDirectHandle
 
                let mut handle = sched_ctx.runtime.get_component_public(target_comp);
 
                handle.send_message(&sched_ctx.runtime, Message::Control(message), true);
 
                let _should_remove = handle.decrement_users();
 
                debug_assert!(_should_remove.is_none());
 
            },
 
            AckAction::ScheduleComponent(to_schedule) => {
 
                // FIX @NoDirectHandle
 
                let mut handle = sched_ctx.runtime.get_component_public(to_schedule);
 

	
 
                // Note that the component is intentionally not
 
                // sleeping, so we just wake it up
 
                debug_assert!(!handle.sleeping.load(std::sync::atomic::Ordering::Acquire));
 
                let key = unsafe { to_schedule.upgrade() };
 
                sched_ctx.runtime.enqueue_work(key);
 
                let _should_remove = handle.decrement_users();
 
                debug_assert!(_should_remove.is_none());
 
            },
 
            AckAction::None => {}
 
        }
 

	
 
        match new_to_ack {
 
            Some(new_to_ack) => to_ack = new_to_ack,
 
            None => break,
 
        }
 
    }
 
}
 

	
 
/// Little helper for sending the most common kind of `Ack`
 
fn default_send_ack(
 
    causer_of_ack_id: ControlId, peer_handle: LocalPeerHandle,
 
    sched_ctx: &SchedulerCtx, comp_ctx: &CompCtx
 
) {
 
    let peer_info = comp_ctx.get_peer(peer_handle);
 
    peer_info.handle.send_message(&sched_ctx.runtime, Message::Control(ControlMessage{
 
        id: causer_of_ack_id,
 
        sender_comp_id: comp_ctx.id,
 
        target_port_id: None,
 
        content: ControlMessageContent::Ack
 
    }), true);
 
}
 

	
 
/// Handles the unblocking of a putter port. In case there is a pending message
 
/// on that port then it will be sent.
 
fn default_handle_unblock_put(
 
    exec_state: &mut CompExecState, consensus: &mut Consensus,
 
    port_handle: LocalPortHandle, sched_ctx: &SchedulerCtx, comp_ctx: &mut CompCtx,
 
) {
 
    let port_info = comp_ctx.get_port_mut(port_handle);
 
    let port_id = port_info.self_id;
 
    debug_assert!(port_info.state.is_blocked());
 
    port_info.state = PortState::Open;
 

	
 
    if exec_state.is_blocked_on_put(port_id) {
 
        // Annotate the message that we're going to send
 
        let port_info = comp_ctx.get_port(port_handle); // for immutable access
 
        debug_assert_eq!(port_info.kind, PortKind::Putter);
 
        let to_send = exec_state.mode_value.take();
 
        let to_send = consensus.annotate_data_message(comp_ctx, port_info, to_send);
 

	
 
        // Retrieve peer to send the message
 
        let peer_handle = comp_ctx.get_peer_handle(port_info.peer_comp_id);
 
        let peer_info = comp_ctx.get_peer(peer_handle);
 
        peer_info.handle.send_message(&sched_ctx.runtime, Message::Data(to_send), true);
 

	
 
        exec_state.mode = CompMode::Sync; // because we're blocked on a `put`, we must've started in the sync state.
 
        exec_state.mode_port = PortId::new_invalid();
 
    }
 
}
 

	
 
#[inline]
 
pub(crate) fn port_id_from_eval(port_id: EvalPortId) -> PortId {
 
    return PortId(port_id.id);
 
}
 

	
 
#[inline]
 
pub(crate) fn port_id_to_eval(port_id: PortId) -> EvalPortId {
 
    return EvalPortId{ id: port_id.0 };
 
}
src/runtime2/component/component_context.rs
Show inline comments
 
use crate::runtime2::scheduler::*;
 
use crate::runtime2::runtime::*;
 
use crate::runtime2::communication::*;
 

	
 
use crate::protocol::ExpressionId;
 

	
 
/// Helper struct to remember when the last operation on the port took place.
 
#[derive(Debug, PartialEq, Copy, Clone)]
 
pub enum PortInstruction {
 
    None,
 
    NoSource,
 
    SourceLocation(ExpressionId),
 
}
 

	
 
#[derive(Debug)]
 
pub struct Port {
 
    // Identifiers
 
    pub self_id: PortId,
 
    pub peer_comp_id: CompId, // eventually consistent
 
    pub peer_port_id: PortId, // eventually consistent
 
    // Generic operating state
 
    pub kind: PortKind,
 
    pub state: PortState,
 
    pub last_instruction: PortInstruction, // used during sync round in case port ends up being closed for error reporting
 
    pub close_at_sync_end: bool, // used during sync round when receiving a `ClosePort(not_in_sync_round)` message
 
    // State tracking for error detection and error handling
 
    pub last_instruction: PortInstruction, // used during sync round to detect port-closed-during-sync errors
 
    pub received_message_for_sync: bool, // used during sync round to detect port-closed-before-sync errors
 
    pub close_at_sync_end: bool, // set during sync round when receiving a port-closed-after-sync message
 
    // Debugging flag to make sure each port is properly associated and
 
    // disassociated with a peer component
 
    #[cfg(debug_assertions)] pub(crate) associated_with_peer: bool,
 
}
 

	
 
pub struct Peer {
 
    pub id: CompId,
 
    pub num_associated_ports: u32,
 
    pub(crate) handle: CompHandle,
 
}
 

	
 
/// Port and peer management structure. Will keep a local reference counter to
 
/// the ports associate with peers, additionally manages the atomic reference
 
/// counter associated with the peers' component handles.
 
pub struct CompCtx {
 
    pub id: CompId,
 
    ports: Vec<Port>,
 
    peers: Vec<Peer>,
 
    port_id_counter: u32,
 
}
 

	
 
#[derive(Copy, Clone, PartialEq, Eq)]
 
pub struct LocalPortHandle(PortId);
 

	
 
#[derive(Copy, Clone)]
 
pub struct LocalPeerHandle(CompId);
 

	
 
impl CompCtx {
 
    /// Creates a new component context based on a reserved entry in the
 
    /// component store. This reservation is used such that we already know our
 
    /// assigned ID.
 
    pub(crate) fn new(reservation: &CompReserved) -> Self {
 
        return Self{
 
            id: reservation.id(),
 
            ports: Vec::new(),
 
            peers: Vec::new(),
 
            port_id_counter: 0,
 
        }
 
    }
 

	
 
    /// Creates a new channel that is fully owned by the component associated
 
    /// with this context.
 
    pub(crate) fn create_channel(&mut self) -> Channel {
 
        let putter_id = PortId(self.take_port_id());
 
        let getter_id = PortId(self.take_port_id());
 
        self.ports.push(Port{
 
            self_id: putter_id,
 
            peer_port_id: getter_id,
 
            kind: PortKind::Putter,
 
            state: PortState::Open,
 
            peer_comp_id: self.id,
 
            last_instruction: PortInstruction::None,
 
            close_at_sync_end: false,
 
            received_message_for_sync: false,
 
            #[cfg(debug_assertions)] associated_with_peer: false,
 
        });
 
        self.ports.push(Port{
 
            self_id: getter_id,
 
            peer_port_id: putter_id,
 
            kind: PortKind::Getter,
 
            state: PortState::Open,
 
            peer_comp_id: self.id,
 
            last_instruction: PortInstruction::None,
 
            close_at_sync_end: false,
 
            received_message_for_sync: false,
 
            #[cfg(debug_assertions)] associated_with_peer: false,
 
        });
 

	
 
        return Channel{ putter_id, getter_id };
 
    }
 

	
 
    /// Adds a new port. Make sure to call `add_peer` afterwards.
 
    pub(crate) fn add_port(&mut self, peer_comp_id: CompId, peer_port_id: PortId, kind: PortKind, state: PortState) -> LocalPortHandle {
 
        let self_id = PortId(self.take_port_id());
 
        self.ports.push(Port{
 
            self_id, peer_comp_id, peer_port_id, kind, state,
 
            last_instruction: PortInstruction::None,
 
            close_at_sync_end: false,
 
            received_message_for_sync: false,
 
            #[cfg(debug_assertions)] associated_with_peer: false,
 
        });
 
        return LocalPortHandle(self_id);
 
    }
 

	
 
    /// Removes a port. Make sure you called `remove_peer` first.
 
    pub(crate) fn remove_port(&mut self, port_handle: LocalPortHandle) -> Port {
 
        let port_index = self.must_get_port_index(port_handle);
 
        let port = self.ports.remove(port_index);
 
        dbg_code!(assert!(!port.associated_with_peer));
 
        return port;
 
    }
 

	
 
    /// Adds a new peer. This must be called for every port, no matter the
 
    /// component the channel is connected to. If a `CompHandle` is supplied,
 
    /// then it will be used to add the peer. Otherwise it will be retrieved
 
    /// from the runtime using its ID.
 
    pub(crate) fn add_peer(&mut self, port_handle: LocalPortHandle, sched_ctx: &SchedulerCtx, peer_comp_id: CompId, handle: Option<&CompHandle>) {
 
        let self_id = self.id;
 
        let port = self.get_port_mut(port_handle);
 
        debug_assert_eq!(port.peer_comp_id, peer_comp_id);
 
        dbg_code!(assert!(!port.associated_with_peer));
 
        if !Self::requires_peer_reference(port, self_id, false) {
 
            return;
 
        }
 

	
 
        dbg_code!(port.associated_with_peer = true);
 
        match self.get_peer_index_by_id(peer_comp_id) {
 
            Some(peer_index) => {
 
                let peer = &mut self.peers[peer_index];
 
                peer.num_associated_ports += 1;
 
            },
 
            None => {
 
                let handle = match handle {
 
                    Some(handle) => handle.clone(),
 
                    None => sched_ctx.runtime.get_component_public(peer_comp_id)
 
                };
 
                self.peers.push(Peer{
 
                    id: peer_comp_id,
 
                    num_associated_ports: 1,
 
                    handle,
 
                });
 
            }
 
        }
 
    }
 

	
 
    /// Removes a peer associated with a port.
 
    pub(crate) fn remove_peer(&mut self, sched_ctx: &SchedulerCtx, port_handle: LocalPortHandle, peer_id: CompId, also_remove_if_closed: bool) {
 
        let self_id = self.id;
 
        let port = self.get_port_mut(port_handle);
 
        debug_assert_eq!(port.peer_comp_id, peer_id);
 
        if !Self::requires_peer_reference(port, self_id, also_remove_if_closed) {
 
            return;
 
        }
 

	
 
        dbg_code!(assert!(port.associated_with_peer));
 
        dbg_code!(port.associated_with_peer = false);
 
        let peer_index = self.get_peer_index_by_id(peer_id).unwrap();
 
        let peer = &mut self.peers[peer_index];
 
        peer.num_associated_ports -= 1;
 
        if peer.num_associated_ports == 0 {
 
            let mut peer = self.peers.remove(peer_index);
 
            if let Some(key) = peer.handle.decrement_users() {
 
                debug_assert_ne!(key.downgrade(), self.id); // should be upheld by the code that shuts down a component
 
                sched_ctx.runtime.destroy_component(key);
 
            }
 
        }
 
    }
 

	
 
    pub(crate) fn set_port_state(&mut self, port_handle: LocalPortHandle, new_state: PortState) {
 
        let port_info = self.get_port_mut(port_handle);
 
        debug_assert_ne!(port_info.state, PortState::Closed); // because then we do not expect to change the state
 
        port_info.state = new_state;
 
    }
 

	
 
    pub(crate) fn get_port_handle(&self, port_id: PortId) -> LocalPortHandle {
 
        return LocalPortHandle(port_id);
 
    }
 

	
 
    // should perhaps be revised, used in main inbox
 
    pub(crate) fn get_port_index(&self, port_handle: LocalPortHandle) -> usize {
 
        return self.must_get_port_index(port_handle);
 
    }
 

	
 
    pub(crate) fn get_peer_handle(&self, peer_id: CompId) -> LocalPeerHandle {
 
        return LocalPeerHandle(peer_id);
 
    }
 

	
 
    pub(crate) fn get_port(&self, port_handle: LocalPortHandle) -> &Port {
 
        let index = self.must_get_port_index(port_handle);
 
        return &self.ports[index];
 
    }
 

	
 
    pub(crate) fn get_port_mut(&mut self, port_handle: LocalPortHandle) -> &mut Port {
 
        let index = self.must_get_port_index(port_handle);
 
        return &mut self.ports[index];
 
    }
 

	
 
    pub(crate) fn get_port_by_index_mut(&mut self, index: usize) -> &mut Port {
 
        return &mut self.ports[index];
 
    }
 

	
 
    pub(crate) fn get_peer(&self, peer_handle: LocalPeerHandle) -> &Peer {
 
        let index = self.must_get_peer_index(peer_handle);
 
        return &self.peers[index];
 
    }
 

	
 
    pub(crate) fn get_peer_mut(&mut self, peer_handle: LocalPeerHandle) -> &mut Peer {
 
        let index = self.must_get_peer_index(peer_handle);
 
        return &mut self.peers[index];
 
    }
 

	
 
    #[inline]
 
    pub(crate) fn iter_ports(&self) -> impl Iterator<Item=&Port> {
 
        return self.ports.iter();
 
    }
 

	
 
    #[inline]
 
    pub(crate) fn iter_ports_mut(&mut self) -> impl Iterator<Item=&mut Port> {
 
        return self.ports.iter_mut();
 
    }
 

	
 
    #[inline]
 
    pub(crate) fn iter_peers(&self) -> impl Iterator<Item=&Peer> {
 
        return self.peers.iter();
 
    }
 

	
 
    #[inline]
 
    pub(crate) fn num_ports(&self) -> usize {
 
        return self.ports.len();
 
    }
 

	
 
    // -------------------------------------------------------------------------
 
    // Local utilities
 
    // -------------------------------------------------------------------------
 

	
 
    #[inline]
 
    fn requires_peer_reference(port: &Port, self_id: CompId, required_if_closed: bool) -> bool {
 
        return (port.state != PortState::Closed || required_if_closed) && port.peer_comp_id != self_id;
 
    }
 

	
 
    fn must_get_port_index(&self, handle: LocalPortHandle) -> usize {
 
        for (index, port) in self.ports.iter().enumerate() {
 
            if port.self_id == handle.0 {
 
                return index;
 
            }
 
        }
 

	
 
        unreachable!()
 
    }
 

	
 
    fn must_get_peer_index(&self, handle: LocalPeerHandle) -> usize {
 
        for (index, peer) in self.peers.iter().enumerate() {
 
            if peer.id == handle.0 {
 
                return index;
 
            }
 
        }
 

	
 
        unreachable!()
 
    }
 

	
 
    fn get_peer_index_by_id(&self, comp_id: CompId) -> Option<usize> {
 
        for (index, peer) in self.peers.iter().enumerate() {
 
            if peer.id == comp_id {
 
                return Some(index);
 
            }
 
        }
 

	
 
        return None;
 
    }
 

	
 
    fn take_port_id(&mut self) -> u32 {
 
        let port_id = self.port_id_counter;
 
        self.port_id_counter = self.port_id_counter.wrapping_add(1);
 
        return port_id;
 
    }
 
}
 
\ No newline at end of file
src/runtime2/component/component_internet.rs
Show inline comments
 
use crate::protocol::eval::{ValueGroup, Value};
 
use crate::runtime2::*;
 
use crate::runtime2::component::{CompCtx, CompId, PortInstruction};
 
use crate::runtime2::stdlib::internet::*;
 
use crate::runtime2::poll::*;
 

	
 
use super::component::{self, *};
 
use super::control_layer::*;
 
use super::consensus::*;
 

	
 
use std::io::ErrorKind as IoErrorKind;
 

	
 
enum SocketState {
 
    Connected(SocketTcpClient),
 
    Error,
 
}
 

	
 
impl SocketState {
 
    fn get_socket(&self) -> &SocketTcpClient {
 
        match self {
 
            SocketState::Connected(v) => v,
 
            SocketState::Error => unreachable!(),
 
        }
 
    }
 
}
 

	
 
/// States from the point of view of the component that is connecting to this
 
/// TCP component (i.e. from the point of view of attempting to interface with
 
/// a socket).
 
#[derive(PartialEq, Debug)]
 
enum SyncState {
 
    AwaitingCmd,
 
    Getting,
 
    Putting,
 
    FinishSync,
 
    FinishSyncThenQuit,
 
}
 

	
 
pub struct ComponentTcpClient {
 
    // Properties for the tcp socket
 
    socket_state: SocketState,
 
    sync_state: SyncState,
 
    poll_ticket: Option<PollTicket>,
 
    inbox_main: Option<DataMessage>,
 
    inbox_backup: Vec<DataMessage>,
 
    pdl_input_port_id: PortId, // input from PDL, so transmitted over socket
 
    pdl_output_port_id: PortId, // output towards PDL, so received over socket
 
    input_union_send_tag_value: i64,
 
    input_union_receive_tag_value: i64,
 
    input_union_finish_tag_value: i64,
 
    input_union_shutdown_tag_value: i64,
 
    // Generic component state
 
    exec_state: CompExecState,
 
    control: ControlLayer,
 
    consensus: Consensus,
 
    // Temporary variables
 
    byte_buffer: Vec<u8>,
 
}
 

	
 
impl Component for ComponentTcpClient {
 
    fn on_creation(&mut self, id: CompId, sched_ctx: &SchedulerCtx) {
 
        // Retrieve type information for messages we're going to receive
 
        let pd = &sched_ctx.runtime.protocol;
 
        let cmd_type = pd.find_type(b"std.internet", b"Cmd")
 
            .expect("'Cmd' type in the 'std.internet' module");
 
        let cmd_type = cmd_type
 
            .as_union();
 

	
 
        self.input_union_send_tag_value = cmd_type.get_variant_tag_value(b"Send").unwrap();
 
        self.input_union_receive_tag_value = cmd_type.get_variant_tag_value(b"Receive").unwrap();
 
        self.input_union_finish_tag_value = cmd_type.get_variant_tag_value(b"Finish").unwrap();
 
        self.input_union_shutdown_tag_value = cmd_type.get_variant_tag_value(b"Shutdown").unwrap();
 

	
 
        // Register socket for async events
 
        if let SocketState::Connected(socket) = &self.socket_state {
 
            let self_handle = sched_ctx.runtime.get_component_public(id);
 
            let poll_ticket = sched_ctx.polling.register(socket, self_handle, true, true)
 
                .expect("registering tcp component");
 

	
 
            debug_assert!(self.poll_ticket.is_none());
 
            self.poll_ticket = Some(poll_ticket);
 
        }
 
    }
 

	
 
    fn on_shutdown(&mut self, sched_ctx: &SchedulerCtx) {
 
        if let Some(poll_ticket) = self.poll_ticket.take() {
 
            sched_ctx.polling.unregister(poll_ticket)
 
                .expect("unregistering tcp component");
 
        }
 
    }
 

	
 
    fn adopt_message(&mut self, _comp_ctx: &mut CompCtx, message: DataMessage) {
 
        if self.inbox_main.is_none() {
 
            self.inbox_main = Some(message);
 
        } else {
 
            self.inbox_backup.push(message);
 
        }
 
    }
 

	
 
    fn handle_message(&mut self, sched_ctx: &mut SchedulerCtx, comp_ctx: &mut CompCtx, message: Message) {
 
        match message {
 
            Message::Data(message) => {
 
                self.handle_incoming_data_message(sched_ctx, comp_ctx, message);
 
            },
 
            Message::Sync(message) => {
 
                let decision = self.consensus.receive_sync_message(sched_ctx, comp_ctx, message);
 
                component::default_handle_sync_decision(sched_ctx, &mut self.exec_state, decision, &mut self.consensus);
 
                component::default_handle_sync_decision(sched_ctx, &mut self.exec_state, comp_ctx, decision, &mut self.consensus);
 
            },
 
            Message::Control(message) => {
 
                if let Err(location_and_message) = component::default_handle_control_message(
 
                    &mut self.exec_state, &mut self.control, &mut self.consensus,
 
                    message, sched_ctx, comp_ctx
 
                ) {
 
                    component::default_handle_error_for_builtin(&mut self.exec_state, sched_ctx, location_and_message);
 
                }
 
            },
 
            Message::Poll => {
 
                sched_ctx.log("Received polling event");
 
            },
 
        }
 
    }
 

	
 
    fn run(&mut self, sched_ctx: &mut SchedulerCtx, comp_ctx: &mut CompCtx) -> CompScheduling {
 
        sched_ctx.log(&format!("Running component ComponentTcpClient (mode: {:?}, sync state: {:?})", self.exec_state.mode, self.sync_state));
 

	
 
        match self.exec_state.mode {
 
            CompMode::BlockedSelect => {
 
                // Not possible: we never enter this state
 
                unreachable!();
 
            },
 
            CompMode::NonSync => {
 
                // When in non-sync mode
 
                match &mut self.socket_state {
 
                    SocketState::Connected(_socket) => {
 
                        if self.sync_state == SyncState::FinishSyncThenQuit {
 
                            // Previous request was to let the component shut down
 
                            self.exec_state.set_as_start_exit(ExitReason::Termination);
 
                        } else {
 
                            // Reset for a new request
 
                            self.sync_state = SyncState::AwaitingCmd;
 
                            self.consensus.notify_sync_start(comp_ctx);
 
                            self.exec_state.mode = CompMode::Sync;
 
                        }
 
                        return CompScheduling::Immediate;
 
                    },
 
                    SocketState::Error => {
 
                        // Could potentially send an error message to the
 
                        // connected component.
 
                        self.exec_state.set_as_start_exit(ExitReason::ErrorNonSync);
 
                        return CompScheduling::Immediate;
 
                    }
 
                }
 
            },
 
            CompMode::Sync => {
 
                // When in sync mode: wait for a command to come in
 
                match self.sync_state {
 
                    SyncState::AwaitingCmd => {
 
                        if let Some(message) = &self.inbox_main {
 
                            self.consensus.handle_incoming_data_message(comp_ctx, &message);
 
                            if self.consensus.try_receive_data_message(sched_ctx, comp_ctx, &message) {
 
                                // Check which command we're supposed to execute.
 
                                let message = self.inbox_main.take().unwrap();
 
                                let target_port_id = message.data_header.target_port;
 
                                let receive_result = component::default_handle_received_data_message(
 
                                    target_port_id, PortInstruction::NoSource,
 
                                    &mut self.inbox_main, &mut self.inbox_backup,
 
                                    comp_ctx, sched_ctx, &mut self.control
 
                                );
 

	
 
                                if let Err(location_and_message) = receive_result {
 
                                    component::default_handle_error_for_builtin(&mut self.exec_state, sched_ctx, location_and_message);
 
                                    return CompScheduling::Immediate;
 
                                } else {
 
                                    let (tag_value, embedded_heap_pos) = message.content.values[0].as_union();
 
                                    if tag_value == self.input_union_send_tag_value {
 
                                        // Retrieve bytes from the message
 
                                        self.byte_buffer.clear();
 
                                        let union_content = &message.content.regions[embedded_heap_pos as usize];
 
                                        debug_assert_eq!(union_content.len(), 1);
 
                                        let array_heap_pos = union_content[0].as_array();
 
                                        let array_values = &message.content.regions[array_heap_pos as usize];
 
                                        self.byte_buffer.reserve(array_values.len());
 
                                        for value in array_values {
 
                                            self.byte_buffer.push(value.as_uint8());
 
                                        }
 

	
 
                                        self.sync_state = SyncState::Putting;
 
                                        return CompScheduling::Immediate;
 
                                    } else if tag_value == self.input_union_receive_tag_value {
 
                                        // Component requires a `recv`
 
                                        self.sync_state = SyncState::Getting;
 
                                        return CompScheduling::Immediate;
 
                                    } else if tag_value == self.input_union_finish_tag_value {
 
                                        // Component requires us to end the sync round
 
                                        self.sync_state = SyncState::FinishSync;
 
                                        return CompScheduling::Immediate;
 
                                    } else if tag_value == self.input_union_shutdown_tag_value {
 
                                        // Component wants to close the connection
 
                                        self.sync_state = SyncState::FinishSyncThenQuit;
 
                                        return CompScheduling::Immediate;
 
                                    } else {
 
                                        unreachable!("got tag_value {}", tag_value)
 
                                    }
 
                                }
 
                            } else {
 
                                todo!("handle sync failure due to message deadlock");
 
                                return CompScheduling::Sleep;
 
                            }
 
                        } else {
 
                            let port_handle = comp_ctx.get_port_handle(self.pdl_input_port_id);
 
                            comp_ctx.get_port_mut(port_handle).last_instruction = PortInstruction::NoSource;
 
                            self.exec_state.set_as_blocked_get(self.pdl_input_port_id);
 
                            return CompScheduling::Sleep;
 
                        }
 
                    },
 
                    SyncState::Putting => {
 
                        // We're supposed to send a user-supplied message fully
 
                        // over the socket. But we might end up blocking. In
 
                        // that case the component goes to sleep until it is
 
                        // polled.
 
                        let socket = self.socket_state.get_socket();
 
                        while !self.byte_buffer.is_empty() {
 
                            match socket.send(&self.byte_buffer) {
 
                                Ok(bytes_sent) => {
 
                                    self.byte_buffer.drain(..bytes_sent);
 
                                },
 
                                Err(err) => {
 
                                    if err.kind() == IoErrorKind::WouldBlock {
 
                                        return CompScheduling::Sleep; // wait until notified
 
                                    } else {
 
                                        todo!("handle socket.send error {:?}", err)
 
                                    }
 
                                }
 
                            }
 
                        }
 

	
 
                        // If here then we're done putting the data, we can
 
                        // finish the sync round
 
                        let decision = self.consensus.notify_sync_end_success(sched_ctx, comp_ctx);
 
                        self.exec_state.mode = CompMode::SyncEnd;
 
                        component::default_handle_sync_decision(sched_ctx, &mut self.exec_state, decision, &mut self.consensus);
 
                        component::default_handle_sync_decision(sched_ctx, &mut self.exec_state, comp_ctx, decision, &mut self.consensus);
 
                        return CompScheduling::Immediate;
 
                    },
 
                    SyncState::Getting => {
 
                        // We're going to try and receive a single message. If
 
                        // this causes us to end up blocking the component
 
                        // goes to sleep until it is polled.
 
                        const BUFFER_SIZE: usize = 1024; // TODO: Move to config
 

	
 
                        let socket = self.socket_state.get_socket();
 
                        self.byte_buffer.resize(BUFFER_SIZE, 0);
 
                        match socket.receive(&mut self.byte_buffer) {
 
                            Ok(num_received) => {
 
                                self.byte_buffer.resize(num_received, 0);
 
                                let message_content = self.bytes_to_data_message_content(&self.byte_buffer);
 
                                let send_result = component::default_send_data_message(&mut self.exec_state, self.pdl_output_port_id, PortInstruction::NoSource, message_content, sched_ctx, &mut self.consensus, comp_ctx);
 
                                if let Err(location_and_message) = send_result {
 
                                    component::default_handle_error_for_builtin(&mut self.exec_state, sched_ctx, location_and_message);
 
                                    return CompScheduling::Immediate;
 
                                } else {
 
                                    let scheduling = send_result.unwrap();
 
                                    self.sync_state = SyncState::AwaitingCmd;
 
                                    return scheduling;
 
                                }
 
                            },
 
                            Err(err) => {
 
                                if err.kind() == IoErrorKind::WouldBlock {
 
                                    return CompScheduling::Sleep; // wait until polled
 
                                } else {
 
                                    todo!("handle socket.receive error {:?}", err)
 
                                }
 
                            }
 
                        }
 
                    },
 
                    SyncState::FinishSync | SyncState::FinishSyncThenQuit => {
 
                        let decision = self.consensus.notify_sync_end_success(sched_ctx, comp_ctx);
 
                        self.exec_state.mode = CompMode::SyncEnd;
 
                        component::default_handle_sync_decision(sched_ctx, &mut self.exec_state, decision, &mut self.consensus);
 
                        component::default_handle_sync_decision(sched_ctx, &mut self.exec_state, comp_ctx, decision, &mut self.consensus);
 
                        return CompScheduling::Requeue;
 
                    },
 
                }
 
            },
 
            CompMode::BlockedGet => {
 
                // Entered when awaiting a new command
 
                debug_assert_eq!(self.sync_state, SyncState::AwaitingCmd);
 
                return CompScheduling::Sleep;
 
            },
 
            CompMode::SyncEnd | CompMode::BlockedPut =>
 
                return CompScheduling::Sleep,
 
            CompMode::StartExit =>
 
                return component::default_handle_start_exit(&mut self.exec_state, &mut self.control, sched_ctx, comp_ctx, &mut self.consensus),
 
            CompMode::BusyExit =>
 
                return component::default_handle_busy_exit(&mut self.exec_state, &mut self.control, sched_ctx),
 
            CompMode::Exit =>
 
                return component::default_handle_exit(&self.exec_state),
 
        }
 
    }
 
}
 

	
 
impl ComponentTcpClient {
 
    pub(crate) fn new(arguments: ValueGroup) -> Self {
 
        use std::net::{IpAddr, Ipv4Addr};
 

	
 
        debug_assert_eq!(arguments.values.len(), 4);
 

	
 
        // Parsing arguments
 
        let ip_heap_pos = arguments.values[0].as_array();
 
        let ip_elements = &arguments.regions[ip_heap_pos as usize];
 
        if ip_elements.len() != 4 {
 
            todo!("friendly error reporting: ip contains 4 octects");
 
        }
 
        let ip_address = IpAddr::V4(Ipv4Addr::new(
 
            ip_elements[0].as_uint8(), ip_elements[1].as_uint8(),
 
            ip_elements[2].as_uint8(), ip_elements[3].as_uint8()
 
        ));
 

	
 
        let port = arguments.values[1].as_uint16();
 
        let input_port = component::port_id_from_eval(arguments.values[2].as_input());
 
        let output_port = component::port_id_from_eval(arguments.values[3].as_output());
 

	
 
        let socket = SocketTcpClient::new(ip_address, port);
 
        if let Err(socket) = socket {
 
            todo!("friendly error reporting: failed to open socket (reason: {:?})", socket);
 
        }
 

	
 
        return Self{
 
            socket_state: SocketState::Connected(socket.unwrap()),
 
            sync_state: SyncState::AwaitingCmd,
 
            poll_ticket: None,
 
            inbox_main: None,
 
            inbox_backup: Vec::new(),
 
            input_union_send_tag_value: -1,
 
            input_union_receive_tag_value: -1,
 
            input_union_finish_tag_value: -1,
 
            input_union_shutdown_tag_value: -1,
 
            pdl_input_port_id: input_port,
 
            pdl_output_port_id: output_port,
 
            exec_state: CompExecState::new(),
 
            control: ControlLayer::default(),
 
            consensus: Consensus::new(),
 
            byte_buffer: Vec::new(),
 
        }
 
    }
 

	
 
    // Handles incoming data from the PDL side (hence, going into the socket)
 
    fn handle_incoming_data_message(&mut self, sched_ctx: &SchedulerCtx, comp_ctx: &mut CompCtx, message: DataMessage) {
 
        if self.exec_state.mode.is_in_sync_block() {
 
            self.consensus.handle_incoming_data_message(comp_ctx, &message);
 
        }
 

	
 
        match component::default_handle_incoming_data_message(
 
            &mut self.exec_state, &mut self.inbox_main, comp_ctx, message, sched_ctx, &mut self.control
 
        ) {
 
            IncomingData::PlacedInSlot => {},
 
            IncomingData::SlotFull(message) => {
 
                self.inbox_backup.push(message);
 
            }
 
        }
 
    }
 

	
 
    fn data_message_to_bytes(&self, message: DataMessage, bytes: &mut Vec<u8>) {
 
        debug_assert_eq!(message.data_header.target_port, self.pdl_input_port_id);
 
        debug_assert_eq!(message.content.values.len(), 1);
 

	
 
        if let Value::Array(array_pos) = message.content.values[0] {
 
            let region = &message.content.regions[array_pos as usize];
 
            bytes.reserve(region.len());
 
            for value in region {
 
                bytes.push(value.as_uint8());
 
            }
 
        } else {
 
            unreachable!();
 
        }
 
    }
 

	
 
    fn bytes_to_data_message_content(&self, buffer: &[u8]) -> ValueGroup {
 
        // Turn bytes into silly executor-style array
 
        let mut values = Vec::with_capacity(buffer.len());
 
        for byte in buffer.iter().copied() {
 
            values.push(Value::UInt8(byte));
 
        }
 

	
 
        // Put in a value group
 
        let mut value_group = ValueGroup::default();
 
        value_group.regions.push(values);
 
        value_group.values.push(Value::Array(0));
 

	
 
        return value_group;
 
    }
 
}
 
\ No newline at end of file
src/runtime2/component/component_pdl.rs
Show inline comments
 
use crate::random::Random;
 
use crate::protocol::*;
 
use crate::protocol::ast::ProcedureDefinitionId;
 
use crate::protocol::eval::{
 
    PortId as EvalPortId, Prompt,
 
    ValueGroup, Value,
 
    EvalContinuation, EvalResult, EvalError
 
};
 

	
 
use crate::runtime2::runtime::CompId;
 
use crate::runtime2::scheduler::SchedulerCtx;
 
use crate::runtime2::communication::*;
 

	
 
use super::component::{
 
    self,
 
    CompExecState, Component, CompScheduling, CompError, CompMode, ExitReason,
 
    port_id_from_eval, port_id_to_eval
 
};
 
use super::component_context::*;
 
use super::control_layer::*;
 
use super::consensus::Consensus;
 

	
 
pub enum ExecStmt {
 
    CreatedChannel((Value, Value)),
 
    PerformedPut,
 
    PerformedGet(ValueGroup),
 
    PerformedSelectWait(u32),
 
    None,
 
}
 

	
 
impl ExecStmt {
 
    fn take(&mut self) -> ExecStmt {
 
        let mut value = ExecStmt::None;
 
        std::mem::swap(self, &mut value);
 
        return value;
 
    }
 

	
 
    fn is_none(&self) -> bool {
 
        match self {
 
            ExecStmt::None => return true,
 
            _ => return false,
 
        }
 
    }
 
}
 

	
 
pub struct ExecCtx {
 
    stmt: ExecStmt,
 
}
 

	
 
impl RunContext for ExecCtx {
 
    fn performed_put(&mut self, _port: EvalPortId) -> bool {
 
        match self.stmt.take() {
 
            ExecStmt::None => return false,
 
            ExecStmt::PerformedPut => return true,
 
            _ => unreachable!(),
 
        }
 
    }
 

	
 
    fn performed_get(&mut self, _port: EvalPortId) -> Option<ValueGroup> {
 
        match self.stmt.take() {
 
            ExecStmt::None => return None,
 
            ExecStmt::PerformedGet(value) => return Some(value),
 
            _ => unreachable!(),
 
        }
 
    }
 

	
 
    fn fires(&mut self, _port: EvalPortId) -> Option<Value> {
 
        todo!("remove fires")
 
    }
 

	
 
    fn performed_fork(&mut self) -> Option<bool> {
 
        todo!("remove fork")
 
    }
 

	
 
    fn created_channel(&mut self) -> Option<(Value, Value)> {
 
        match self.stmt.take() {
 
            ExecStmt::None => return None,
 
            ExecStmt::CreatedChannel(ports) => return Some(ports),
 
            _ => unreachable!(),
 
        }
 
    }
 

	
 
    fn performed_select_wait(&mut self) -> Option<u32> {
 
        match self.stmt.take() {
 
            ExecStmt::None => return None,
 
            ExecStmt::PerformedSelectWait(selected_case) => Some(selected_case),
 
            _v => unreachable!(),
 
        }
 
    }
 
}
 

	
 
struct SelectCase {
 
    involved_ports: Vec<LocalPortHandle>,
 
}
 

	
 
// TODO: @Optimize, flatten cases into single array, have index-pointers to next case
 
struct SelectState {
 
    cases: Vec<SelectCase>,
 
    next_case: u32,
 
    num_cases: u32,
 
    random: Random,
 
    candidates_workspace: Vec<usize>,
 
}
 

	
 
enum SelectDecision {
 
    None,
 
    Case(u32), // contains case index, should be passed along to PDL code
 
}
 

	
 
type InboxMain = Vec<Option<DataMessage>>;
 

	
 
impl SelectState {
 
    fn new() -> Self {
 
        return Self{
 
            cases: Vec::new(),
 
            next_case: 0,
 
            num_cases: 0,
 
            random: Random::new(),
 
            candidates_workspace: Vec::new(),
 
        }
 
    }
 

	
 
    fn handle_select_start(&mut self, num_cases: u32) {
 
        self.cases.clear();
 
        self.next_case = 0;
 
        self.num_cases = num_cases;
 
    }
 

	
 
    /// Register a port as belonging to a particular case. As for correctness of
 
    /// PDL code one cannot register the same port twice, this function might
 
    /// return an error
 
    fn register_select_case_port(&mut self, comp_ctx: &CompCtx, case_index: u32, _port_index: u32, port_id: PortId) -> Result<(), PortId> {
 
        // Retrieve case and port handle
 
        self.ensure_at_case(case_index);
 
        let cur_case = &mut self.cases[case_index as usize];
 
        let port_handle = comp_ctx.get_port_handle(port_id);
 
        debug_assert_eq!(cur_case.involved_ports.len(), _port_index as usize);
 

	
 
        // Make sure port wasn't added before, we disallow having the same port
 
        // in the same select guard twice.
 
        if cur_case.involved_ports.contains(&port_handle) {
 
            return Err(port_id);
 
        }
 

	
 
        cur_case.involved_ports.push(port_handle);
 
        return Ok(());
 
    }
 

	
 
    /// Notification that all ports have been registered and we should now wait
 
    /// until the appropriate messages have come in.
 
    fn handle_select_waiting_point(&mut self, inbox: &InboxMain, comp_ctx: &CompCtx) -> SelectDecision {
 
        if self.num_cases != self.next_case {
 
            // This happens when there are >=1 select cases written at the end
 
            // of the select block.
 
            self.ensure_at_case(self.num_cases - 1);
 
        }
 

	
 
        return self.has_decision(inbox, comp_ctx);
 
    }
 

	
 
    fn handle_updated_inbox(&mut self, inbox: &InboxMain, comp_ctx: &CompCtx) -> SelectDecision {
 
        return self.has_decision(inbox, comp_ctx);
 
    }
 

	
 
    /// Internal helper, pushes empty cases inbetween last case and provided new
 
    /// case index.
 
    fn ensure_at_case(&mut self, new_case_index: u32) {
 
        // Push an empty case for all intermediate cases that were not
 
        // registered with a port.
 
        debug_assert!(new_case_index >= self.next_case && new_case_index < self.num_cases);
 
        for _ in self.next_case..new_case_index + 1 {
 
            self.cases.push(SelectCase{ involved_ports: Vec::new() });
 
        }
 
        self.next_case = new_case_index + 1;
 
    }
 

	
 
    /// Checks if a decision can be reached
 
    fn has_decision(&mut self, inbox: &InboxMain, comp_ctx: &CompCtx) -> SelectDecision {
 
        self.candidates_workspace.clear();
 
        if self.cases.is_empty() {
 
            // If there are no cases then we can immediately reach a "bogus
 
            // decision".
 
            return SelectDecision::Case(0);
 
        }
 

	
 
        // Need to check for valid case
 
        'case_loop: for (case_index, case) in self.cases.iter().enumerate() {
 
            for port_handle in case.involved_ports.iter().copied() {
 
                let port_index = comp_ctx.get_port_index(port_handle);
 
                if inbox[port_index].is_none() {
 
                    // Condition not satisfied
 
                    continue 'case_loop;
 
                }
 
            }
 

	
 
            // If here then the case guard is satisfied
 
            self.candidates_workspace.push(case_index);
 
        }
 

	
 
        if self.candidates_workspace.is_empty() {
 
            return SelectDecision::None;
 
        } else {
 
            let candidate_index = self.random.get_u64() as usize % self.candidates_workspace.len();
 
            return SelectDecision::Case(self.candidates_workspace[candidate_index] as u32);
 
        }
 
    }
 
}
 

	
 
pub(crate) struct CompPDL {
 
    pub exec_state: CompExecState,
 
    select_state: SelectState,
 
    pub prompt: Prompt,
 
    pub control: ControlLayer,
 
    pub consensus: Consensus,
 
    pub sync_counter: u32,
 
    pub exec_ctx: ExecCtx,
 
    // TODO: Temporary field, simulates future plans of having one storage place
 
    //  reserved per port.
 
    // Should be same length as the number of ports. Corresponding indices imply
 
    // message is intended for that port.
 
    pub inbox_main: InboxMain,
 
    pub inbox_backup: Vec<DataMessage>,
 
}
 

	
 
impl Component for CompPDL {
 
    fn on_creation(&mut self, _id: CompId, _sched_ctx: &SchedulerCtx) {
 
        // Intentionally empty
 
    }
 

	
 
    fn on_shutdown(&mut self, _sched_ctx: &SchedulerCtx) {
 
        // Intentionally empty
 
    }
 

	
 
    fn adopt_message(&mut self, comp_ctx: &mut CompCtx, message: DataMessage) {
 
        let port_handle = comp_ctx.get_port_handle(message.data_header.target_port);
 
        let port_index = comp_ctx.get_port_index(port_handle);
 
        if self.inbox_main[port_index].is_none() {
 
            self.inbox_main[port_index] = Some(message);
 
        } else {
 
            self.inbox_backup.push(message);
 
        }
 
    }
 

	
 
    fn handle_message(&mut self, sched_ctx: &mut SchedulerCtx, comp_ctx: &mut CompCtx, mut message: Message) {
 
        // sched_ctx.log(&format!("handling message: {:?}", message));
 
        if let Some(new_target) = self.control.should_reroute(&mut message) {
 
            let mut target = sched_ctx.runtime.get_component_public(new_target); // TODO: @NoDirectHandle
 
            target.send_message(&sched_ctx.runtime, message, false); // not waking up: we schedule once we've received all PortPeerChanged Acks
 
            let _should_remove = target.decrement_users();
 
            debug_assert!(_should_remove.is_none());
 
            return;
 
        }
 

	
 
        match message {
 
            Message::Data(message) => {
 
                self.handle_incoming_data_message(sched_ctx, comp_ctx, message);
 
            },
 
            Message::Control(message) => {
 
                if let Err(location_and_message) = component::default_handle_control_message(
 
                    &mut self.exec_state, &mut self.control, &mut self.consensus,
 
                    message, sched_ctx, comp_ctx
 
                ) {
 
                    self.handle_generic_component_error(sched_ctx, location_and_message);
 
                }
 
            },
 
            Message::Sync(message) => {
 
                self.handle_incoming_sync_message(sched_ctx, comp_ctx, message);
 
            },
 
            Message::Poll => {
 
                unreachable!(); // because we never register at the polling thread
 
            }
 
        }
 
    }
 

	
 
    fn run(&mut self, sched_ctx: &mut SchedulerCtx, comp_ctx: &mut CompCtx) -> CompScheduling {
 
        use EvalContinuation as EC;
 

	
 
        sched_ctx.log(&format!("Running component (mode: {:?})", self.exec_state.mode));
 

	
 
        // Depending on the mode don't do anything at all, take some special
 
        // actions, or fall through and run the PDL code.
 
        match self.exec_state.mode {
 
            CompMode::NonSync | CompMode::Sync => {
 
                // continue and run PDL code
 
            },
 
            CompMode::SyncEnd | CompMode::BlockedGet | CompMode::BlockedPut | CompMode::BlockedSelect => {
 
                return CompScheduling::Sleep;
 
            }
 
            CompMode::StartExit => return component::default_handle_start_exit(
 
                &mut self.exec_state, &mut self.control, sched_ctx, comp_ctx, &mut self.consensus
 
            ),
 
            CompMode::BusyExit => return component::default_handle_busy_exit(
 
                &mut self.exec_state, &self.control, sched_ctx
 
            ),
 
            CompMode::Exit => return component::default_handle_exit(&self.exec_state),
 
        }
 

	
 
        let run_result = self.execute_prompt(&sched_ctx);
 
        if let Err(error) = run_result {
 
            self.handle_component_error(sched_ctx, CompError::Executor(error));
 
            return CompScheduling::Immediate;
 
        }
 

	
 
        let run_result = run_result.unwrap();
 

	
 
        match run_result {
 
            EC::Stepping => unreachable!(), // execute_prompt runs until this is no longer returned
 
            EC::BranchInconsistent | EC::NewFork | EC::BlockFires(_) => todo!("remove these"),
 
            // Results that can be returned in sync mode
 
            EC::SyncBlockEnd => {
 
                debug_assert_eq!(self.exec_state.mode, CompMode::Sync);
 
                self.handle_sync_end(sched_ctx, comp_ctx);
 
                return CompScheduling::Immediate;
 
            },
 
            EC::BlockGet(expr_id, port_id) => {
 
                debug_assert_eq!(self.exec_state.mode, CompMode::Sync);
 
                debug_assert!(self.exec_ctx.stmt.is_none());
 

	
 
                let port_id = port_id_from_eval(port_id);
 
                let port_handle = comp_ctx.get_port_handle(port_id);
 

	
 
                let port_info = comp_ctx.get_port_mut(port_handle);
 
                port_info.last_instruction = PortInstruction::SourceLocation(expr_id);
 
                let port_is_closed = port_info.state == PortState::Closed;
 

	
 
                let port_index = comp_ctx.get_port_index(port_handle);
 
                if let Some(message) = &self.inbox_main[port_index] {
 
                    // Check if we can actually receive the message
 
                    if self.consensus.try_receive_data_message(sched_ctx, comp_ctx, message) {
 
                        // Message was received. Make sure any blocked peers and
 
                        // pending messages are handled.
 
                        let message = self.inbox_main[port_index].take().unwrap();
 
                        let receive_result = component::default_handle_received_data_message(
 
                            port_id, PortInstruction::SourceLocation(expr_id),
 
                            &mut self.inbox_main[port_index], &mut self.inbox_backup,
 
                            comp_ctx, sched_ctx, &mut self.control
 
                        );
 
                        if let Err(location_and_message) = receive_result {
 
                            self.handle_generic_component_error(sched_ctx, location_and_message);
 
                            return CompScheduling::Immediate
 
                        } else {
 
                            self.exec_ctx.stmt = ExecStmt::PerformedGet(message.content);
 
                            return CompScheduling::Immediate;
 
                        }
 
                    } else {
 
                        let protocol = &sched_ctx.runtime.protocol;
 
                        self.handle_component_error(sched_ctx, CompError::Executor(EvalError::new_error_at_expr(
 
                            &self.prompt, &protocol.modules, &protocol.heap, expr_id,
 
                            String::from("Cannot get from this port, as this causes a deadlock. This happens if you `get` in a different order as another component `put`s")
 
                        ));
 
                        )));
 
                        return CompScheduling::Sleep;
 
                    }
 
                } else if port_is_closed {
 
                    // No messages, but getting makes no sense as the port is
 
                    // closed.
 
                    let peer_id = comp_ctx.get_port(port_handle).peer_comp_id;
 
                    let protocol = &sched_ctx.runtime.protocol;
 
                    self.handle_component_error(sched_ctx, CompError::Executor(EvalError::new_error_at_expr(
 
                        &self.prompt, &protocol.modules, &protocol.heap, expr_id,
 
                        format!("Cannot get from this port, as the peer component (id:{}) shut down", peer_id.0)
 
                    )));
 
                    return CompScheduling::Immediate;
 
                } else {
 
                    // We need to wait
 
                    self.exec_state.set_as_blocked_get(port_id);
 
                    return CompScheduling::Sleep;
 
                }
 
            },
 
            EC::Put(expr_id, port_id, value) => {
 
                debug_assert_eq!(self.exec_state.mode, CompMode::Sync);
 
                sched_ctx.log(&format!("Putting value {:?}", value));
 

	
 
                // Send the message
 
                let target_port_id = port_id_from_eval(port_id);
 
                let send_result = component::default_send_data_message(
 
                    &mut self.exec_state, target_port_id,
 
                    PortInstruction::SourceLocation(expr_id), value,
 
                    sched_ctx, &mut self.consensus, comp_ctx
 
                );
 
                if let Err(location_and_message) = send_result {
 
                    self.handle_generic_component_error(sched_ctx, location_and_message);
 
                    return CompScheduling::Immediate;
 
                } else {
 
                    // When `run` is called again (potentially after becoming
 
                    // unblocked) we need to instruct the executor that we performed
 
                    // the `put`
 
                    let scheduling = send_result.unwrap();
 
                    self.exec_ctx.stmt = ExecStmt::PerformedPut;
 
                    return scheduling;
 
                }
 
            },
 
            EC::SelectStart(num_cases, _num_ports) => {
 
                debug_assert_eq!(self.exec_state.mode, CompMode::Sync);
 
                self.select_state.handle_select_start(num_cases);
 
                return CompScheduling::Requeue;
 
            },
 
            EC::SelectRegisterPort(expr_id, case_index, port_index, port_id) => {
 
                debug_assert_eq!(self.exec_state.mode, CompMode::Sync);
 
                let port_id = port_id_from_eval(port_id);
 
                let port_handle = comp_ctx.get_port_handle(port_id);
 

	
 
                // Note: we register the "last_instruction" here already. This
 
                // way if we get a `ClosePort` message, the condition to fail
 
                // the synchronous round is satisfied.
 
                let port_info = comp_ctx.get_port_mut(port_handle);
 
                port_info.last_instruction = PortInstruction::SourceLocation(expr_id);
 
                let port_is_closed = port_info.state == PortState::Closed;
 

	
 
                // Register port as part of select guard
 
                if let Err(_err) = self.select_state.register_select_case_port(comp_ctx, case_index, port_index, port_id) {
 
                    // Failure occurs if a port is used twice in the same guard
 
                    let protocol = &sched_ctx.runtime.protocol;
 
                    self.handle_component_error(sched_ctx, CompError::Executor(EvalError::new_error_at_expr(
 
                        &self.prompt, &protocol.modules, &protocol.heap, expr_id,
 
                        String::from("Cannot have the one port appear in the same guard twice")
 
                    )));
 
                } else if port_is_closed {
 
                    // Port is closed
 
                    let peer_id = comp_ctx.get_port(port_handle).peer_comp_id;
 
                    let protocol = &sched_ctx.runtime.protocol;
 
                    self.handle_component_error(sched_ctx, CompError::Executor(EvalError::new_error_at_expr(
 
                        &self.prompt, &protocol.modules, &protocol.heap, expr_id,
 
                        format!("Cannot register port, as the peer component (id:{}) has shut down", peer_id.0)
 
                    )));
 
                }
 

	
 
                return CompScheduling::Immediate;
 
            },
 
            EC::SelectWait => {
 
                debug_assert_eq!(self.exec_state.mode, CompMode::Sync);
 
                let select_decision = self.select_state.handle_select_waiting_point(&self.inbox_main, comp_ctx);
 
                if let SelectDecision::Case(case_index) = select_decision {
 
                    // Reached a conclusion, so we can continue immediately
 
                    self.exec_ctx.stmt = ExecStmt::PerformedSelectWait(case_index);
 
                    self.exec_state.mode = CompMode::Sync;
 
                    return CompScheduling::Immediate;
 
                } else {
 
                    // No decision yet
 
                    self.exec_state.mode = CompMode::BlockedSelect;
 
                    return CompScheduling::Sleep;
 
                }
 
            },
 
            // Results that can be returned outside of sync mode
 
            EC::ComponentTerminated => {
 
                self.exec_state.set_as_start_exit(ExitReason::Termination);
 
                return CompScheduling::Immediate;
 
            },
 
            EC::SyncBlockStart => {
 
                debug_assert_eq!(self.exec_state.mode, CompMode::NonSync);
 
                self.handle_sync_start(sched_ctx, comp_ctx);
 
                return CompScheduling::Immediate;
 
            },
 
            EC::NewComponent(definition_id, type_id, arguments) => {
 
                debug_assert_eq!(self.exec_state.mode, CompMode::NonSync);
 
                self.create_component_and_transfer_ports(
 
                    sched_ctx, comp_ctx,
 
                    definition_id, type_id, arguments
 
                );
 
                return CompScheduling::Requeue;
 
            },
 
            EC::NewChannel => {
 
                debug_assert_eq!(self.exec_state.mode, CompMode::NonSync);
 
                debug_assert!(self.exec_ctx.stmt.is_none());
 
                let channel = comp_ctx.create_channel();
 
                self.exec_ctx.stmt = ExecStmt::CreatedChannel((
 
                    Value::Output(port_id_to_eval(channel.putter_id)),
 
                    Value::Input(port_id_to_eval(channel.getter_id))
 
                ));
 
                self.inbox_main.push(None);
 
                self.inbox_main.push(None);
 
                return CompScheduling::Immediate;
 
            }
 
        }
 
    }
 
}
 

	
 
impl CompPDL {
 
    pub(crate) fn new(initial_state: Prompt, num_ports: usize) -> Self {
 
        let mut inbox_main = Vec::new();
 
        inbox_main.reserve(num_ports);
 
        for _ in 0..num_ports {
 
            inbox_main.push(None);
 
        }
 

	
 
        return Self{
 
            exec_state: CompExecState::new(),
 
            select_state: SelectState::new(),
 
            prompt: initial_state,
 
            control: ControlLayer::default(),
 
            consensus: Consensus::new(),
 
            sync_counter: 0,
 
            exec_ctx: ExecCtx{
 
                stmt: ExecStmt::None,
 
            },
 
            inbox_main,
 
            inbox_backup: Vec::new(),
 
        }
 
    }
 

	
 
    // -------------------------------------------------------------------------
 
    // Running component and handling changes in global component state
 
    // -------------------------------------------------------------------------
 

	
 
    fn execute_prompt(&mut self, sched_ctx: &SchedulerCtx) -> EvalResult {
 
        let mut step_result = EvalContinuation::Stepping;
 
        while let EvalContinuation::Stepping = step_result {
 
            step_result = self.prompt.step(
 
                &sched_ctx.runtime.protocol.types, &sched_ctx.runtime.protocol.heap,
 
                &sched_ctx.runtime.protocol.modules, &mut self.exec_ctx,
 
            )?;
 
        }
 

	
 
        return Ok(step_result)
 
    }
 

	
 
    fn handle_sync_start(&mut self, sched_ctx: &SchedulerCtx, comp_ctx: &mut CompCtx) {
 
        sched_ctx.log("Component starting sync mode");
 
        self.consensus.notify_sync_start(comp_ctx);
 
        for message in self.inbox_main.iter() {
 
            if let Some(message) = message {
 
                self.consensus.handle_incoming_data_message(comp_ctx, message);
 
            }
 
        }
 
        debug_assert_eq!(self.exec_state.mode, CompMode::NonSync);
 
        self.exec_state.mode = CompMode::Sync;
 
    }
 

	
 
    /// Handles end of sync. The conclusion to the sync round might arise
 
    /// immediately (and be handled immediately), or might come later through
 
    /// messaging. In any case the component should be scheduled again
 
    /// immediately
 
    fn handle_sync_end(&mut self, sched_ctx: &SchedulerCtx, comp_ctx: &mut CompCtx) {
 
        sched_ctx.log("Component ending sync mode (now waiting for solution)");
 
        let decision = self.consensus.notify_sync_end_success(sched_ctx, comp_ctx);
 
        self.exec_state.mode = CompMode::SyncEnd;
 
        component::default_handle_sync_decision(sched_ctx, &mut self.exec_state, comp_ctx, decision, &mut self.consensus);
 
    }
 

	
 
    fn handle_component_exit(&mut self, sched_ctx: &SchedulerCtx, comp_ctx: &mut CompCtx) {
 
        sched_ctx.log(&format!("Component exiting (reason: {:?}", self.exec_state.exit_reason));
 
        debug_assert_eq!(self.exec_state.mode, CompMode::StartExit);
 
        self.exec_state.mode = CompMode::BusyExit;
 
        let exit_inside_sync = self.exec_state.exit_reason.is_in_sync();
 

	
 
        // Doing this by index, then retrieving the handle is a bit rediculous,
 
        // but Rust is being Rust with its borrowing rules.
 
        for port_index in 0..comp_ctx.num_ports() {
 
            let port = comp_ctx.get_port_by_index_mut(port_index);
 
            if port.state == PortState::Closed {
 
                // Already closed, or in the process of being closed
 
                continue;
 
            }
 

	
 
            // Mark as closed
 
            let port_id = port.self_id;
 
            port.state = PortState::Closed;
 

	
 
            // Notify peer of closing
 
            let port_handle = comp_ctx.get_port_handle(port_id);
 
            let (peer, message) = self.control.initiate_port_closing(port_handle, exit_inside_sync, comp_ctx);
 
            let peer_info = comp_ctx.get_peer(peer);
 
            peer_info.handle.send_message(&sched_ctx.runtime, Message::Control(message), true);
 
        }
 
    }
 

	
 
    // -------------------------------------------------------------------------
 
    // Handling messages
 
    // -------------------------------------------------------------------------
 

	
 
    /// Handles a message that came in through the public inbox. This function
 
    /// will handle putting it in the correct place, and potentially blocking
 
    /// the port in case too many messages are being received.
 
    fn handle_incoming_data_message(&mut self, sched_ctx: &SchedulerCtx, comp_ctx: &mut CompCtx, message: DataMessage) {
 
        use component::IncomingData;
 

	
 
        // Whatever we do, glean information from headers in message
 
        if self.exec_state.mode.is_in_sync_block() {
 
            self.consensus.handle_incoming_data_message(comp_ctx, &message);
 
        }
 

	
 
        let port_handle = comp_ctx.get_port_handle(message.data_header.target_port);
 
        let port_index = comp_ctx.get_port_index(port_handle);
 
        match component::default_handle_incoming_data_message(
 
            &mut self.exec_state, &mut self.inbox_main[port_index], comp_ctx, message,
 
            sched_ctx, &mut self.control
 
        ) {
 
            IncomingData::PlacedInSlot => {
 
                if self.exec_state.mode == CompMode::BlockedSelect {
 
                    let select_decision = self.select_state.handle_updated_inbox(&self.inbox_main, comp_ctx);
 
                    if let SelectDecision::Case(case_index) = select_decision {
 
                        self.exec_ctx.stmt = ExecStmt::PerformedSelectWait(case_index);
 
                        self.exec_state.mode = CompMode::Sync;
 
                    }
 
                }
 
            },
 
            IncomingData::SlotFull(message) => {
 
                self.inbox_backup.push(message);
 
            }
 
        }
 
    }
 

	
 
    fn handle_incoming_sync_message(&mut self, sched_ctx: &SchedulerCtx, comp_ctx: &mut CompCtx, message: SyncMessage) {
 
        let decision = self.consensus.receive_sync_message(sched_ctx, comp_ctx, message);
 
        component::default_handle_sync_decision(sched_ctx, &mut self.exec_state, decision, &mut self.consensus);
 
        component::default_handle_sync_decision(sched_ctx, &mut self.exec_state, comp_ctx, decision, &mut self.consensus);
 
    }
 

	
 
    /// Handles an error coming from the generic `component::handle_xxx`
 
    /// functions. Hence accepts argument as a tuple.
 
    fn handle_generic_component_error(&mut self, sched_ctx: &SchedulerCtx, location_and_message: (PortInstruction, String)) {
 
        // Retrieve location and message, display in terminal
 
        let (location, message) = location_and_message;
 
        let error = match location {
 
            PortInstruction::None => CompError::Component(message),
 
            PortInstruction::NoSource => unreachable!(), // for debugging: all in-sync errors are associated with a source location
 
            PortInstruction::SourceLocation(expression_id) => {
 
                let protocol = &sched_ctx.runtime.protocol;
 
                CompError::Executor(EvalError::new_error_at_expr(
 
                    &self.prompt, &protocol.modules, &protocol.heap,
 
                    expression_id, message
 
                ))
 
            }
 
        };
 

	
 
        self.handle_component_error(sched_ctx, error);
 
    }
 

	
 
    fn handle_component_error(&mut self, sched_ctx: &SchedulerCtx, error: CompError) {
 
        sched_ctx.error(&format!("{}", error));
 

	
 
        // Set state to handle subsequent error
 
        let exit_reason = if self.exec_state.mode.is_in_sync_block() {
 
            ExitReason::ErrorInSync
 
        } else {
 
            ExitReason::ErrorNonSync
 
        };
 

	
 
        self.exec_state.set_as_start_exit(exit_reason);
 
    }
 

	
 
    // -------------------------------------------------------------------------
 
    // Handling ports
 
    // -------------------------------------------------------------------------
 

	
 
    /// Creates a new component and transfers ports. Because of the stepwise
 
    /// process in which memory is allocated, ports are transferred, messages
 
    /// are exchanged, component lifecycle methods are called, etc. This
 
    /// function facilitates a lot of implicit assumptions (e.g. when the
 
    /// `Component::on_creation` method is called, the component is already
 
    /// registered at the runtime).
 
    fn create_component_and_transfer_ports(
 
        &mut self,
 
        sched_ctx: &SchedulerCtx, creator_ctx: &mut CompCtx,
 
        definition_id: ProcedureDefinitionId, type_id: TypeId, mut arguments: ValueGroup
 
    ) {
 
        struct PortPair{
 
            creator_handle: LocalPortHandle,
 
            creator_id: PortId,
 
            created_handle: LocalPortHandle,
 
            created_id: PortId,
 
        }
 
        let mut opened_port_id_pairs = Vec::new();
 
        let mut closed_port_id_pairs = Vec::new();
 

	
 
        let reservation = sched_ctx.runtime.start_create_pdl_component();
 
        let mut created_ctx = CompCtx::new(&reservation);
 

	
 
        let other_proc = &sched_ctx.runtime.protocol.heap[definition_id];
 
        let self_proc = &sched_ctx.runtime.protocol.heap[self.prompt.frames[0].definition];
 

	
 
        // dbg_code!({
 
        //     sched_ctx.log(&format!(
 
        //         "DEBUG: Comp '{}' (ID {:?}) is creating comp '{}' (ID {:?})",
 
        //         self_proc.identifier.value.as_str(), creator_ctx.id,
 
        //         other_proc.identifier.value.as_str(), reservation.id()
 
        //     ));
 
        // });
 

	
 
        // Take all the ports ID that are in the `args` (and currently belong to
 
        // the creator component) and translate them into new IDs that are
 
        // associated with the component we're about to create
 
        let mut arg_iter = ValueGroupPortIter::new(&mut arguments);
 
        while let Some(port_reference) = arg_iter.next() {
 
            // Create port entry for new component
 
            let creator_port_id = port_reference.id;
 
            let creator_port_handle = creator_ctx.get_port_handle(creator_port_id);
 
            let creator_port = creator_ctx.get_port(creator_port_handle);
 
            let created_port_handle = created_ctx.add_port(
 
                creator_port.peer_comp_id, creator_port.peer_port_id,
 
                creator_port.kind, creator_port.state
 
            );
 
            let created_port = created_ctx.get_port(created_port_handle);
 
            let created_port_id = created_port.self_id;
 

	
 
            let port_id_pair = PortPair {
 
                creator_handle: creator_port_handle,
 
                creator_id: creator_port_id,
 
                created_handle: created_port_handle,
 
                created_id: created_port_id,
 
            };
 

	
 
            if creator_port.state == PortState::Closed {
 
                closed_port_id_pairs.push(port_id_pair)
 
            } else {
 
                opened_port_id_pairs.push(port_id_pair);
 
            }
 

	
 
            // Modify value in arguments (bit dirty, but double vec in ValueGroup causes lifetime issues)
 
            let arg_value = if let Some(heap_pos) = port_reference.heap_pos {
 
                &mut arg_iter.group.regions[heap_pos][port_reference.index]
 
            } else {
 
                &mut arg_iter.group.values[port_reference.index]
 
            };
 
            match arg_value {
 
                Value::Input(id) => *id = port_id_to_eval(created_port_id),
 
                Value::Output(id) => *id = port_id_to_eval(created_port_id),
 
                _ => unreachable!(),
 
            }
 
        }
 

	
 
        // For each transferred port pair set their peer components to the
 
        // correct values. This will only change the values for the ports of
 
        // the new component.
 
        let mut created_component_has_remote_peers = false;
 

	
 
        for pair in opened_port_id_pairs.iter() {
 
            let creator_port_info = creator_ctx.get_port(pair.creator_handle);
 
            let created_port_info = created_ctx.get_port_mut(pair.created_handle);
 

	
 
            if created_port_info.peer_comp_id == creator_ctx.id {
 
                // Port peer is owned by the creator as well
 
                let created_peer_port_index = opened_port_id_pairs
 
                    .iter()
 
                    .position(|v| v.creator_id == creator_port_info.peer_port_id);
 
                match created_peer_port_index {
 
                    Some(created_peer_port_index) => {
 
                        // Peer port moved to the new component as well. So
 
                        // adjust IDs appropriately.
 
                        let peer_pair = &opened_port_id_pairs[created_peer_port_index];
 
                        created_port_info.peer_port_id = peer_pair.created_id;
 
                        created_port_info.peer_comp_id = reservation.id();
 
                        todo!("either add 'self peer', or remove that idea from Ctx altogether")
 
                    },
 
                    None => {
 
                        // Peer port remains with creator component.
 
                        created_port_info.peer_comp_id = creator_ctx.id;
 
                        created_ctx.add_peer(pair.created_handle, sched_ctx, creator_ctx.id, None);
 
                    }
 
                }
 
            } else {
 
                // Peer is a different component. We'll deal with sending the
 
                // appropriate messages later
 
                let peer_handle = creator_ctx.get_peer_handle(created_port_info.peer_comp_id);
 
                let peer_info = creator_ctx.get_peer(peer_handle);
 
                created_ctx.add_peer(pair.created_handle, sched_ctx, peer_info.id, Some(&peer_info.handle));
 
                created_component_has_remote_peers = true;
 
            }
 
        }
 

	
 
        // We'll now actually turn our reservation for a new component into an
 
        // actual component. Note that we initialize it as "not sleeping" as
 
        // its initial scheduling might be performed based on `Ack`s in response
 
        // to message exchanges between remote peers.
 
        let total_num_ports = opened_port_id_pairs.len() + closed_port_id_pairs.len();
 
        let component = component::create_component(&sched_ctx.runtime.protocol, definition_id, type_id, arguments, total_num_ports);
 
        let (created_key, component) = sched_ctx.runtime.finish_create_pdl_component(
 
            reservation, component, created_ctx, false,
 
        );
 
        component.component.on_creation(created_key.downgrade(), sched_ctx);
 

	
 
        // Now modify the creator's ports: remove every transferred port and
 
        // potentially remove the peer component.
 
        for pair in opened_port_id_pairs.iter() {
 
            // Remove peer if appropriate
 
            let creator_port_info = creator_ctx.get_port(pair.creator_handle);
 
            let creator_port_index = creator_ctx.get_port_index(pair.creator_handle);
 
            let creator_peer_comp_id = creator_port_info.peer_comp_id;
 
            creator_ctx.remove_peer(sched_ctx, pair.creator_handle, creator_peer_comp_id, false);
 
            creator_ctx.remove_port(pair.creator_handle);
 

	
 
            // Transfer any messages
 
            if let Some(mut message) = self.inbox_main.remove(creator_port_index) {
 
                message.data_header.target_port = pair.created_id;
 
                component.component.adopt_message(&mut component.ctx, message)
 
            }
 

	
 
            let mut message_index = 0;
 
            while message_index < self.inbox_backup.len() {
 
                let message = &self.inbox_backup[message_index];
 
                if message.data_header.target_port == pair.creator_id {
 
                    // transfer message
 
                    let mut message = self.inbox_backup.remove(message_index);
 
                    message.data_header.target_port = pair.created_id;
 
                    component.component.adopt_message(&mut component.ctx, message);
 
                } else {
 
                    message_index += 1;
 
                }
 
            }
 

	
 
            // Handle potential channel between creator and created component
 
            let created_port_info = component.ctx.get_port(pair.created_handle);
 

	
 
            if created_port_info.peer_comp_id == creator_ctx.id {
 
                let peer_port_handle = creator_ctx.get_port_handle(created_port_info.peer_port_id);
 
                let peer_port_info = creator_ctx.get_port_mut(peer_port_handle);
 
                peer_port_info.peer_comp_id = component.ctx.id;
 
                peer_port_info.peer_port_id = created_port_info.self_id;
 
                creator_ctx.add_peer(peer_port_handle, sched_ctx, component.ctx.id, None);
 
            }
 
        }
 

	
 
        // Do the same for the closed ports
 
        for pair in closed_port_id_pairs.iter() {
 
            let port_index = creator_ctx.get_port_index(pair.creator_handle);
 
            creator_ctx.remove_port(pair.creator_handle);
 
            let _removed_message = self.inbox_main.remove(port_index);
 

	
 
            // In debug mode: since we've closed the port we shouldn't have any
 
            // messages for that port.
 
            debug_assert!(_removed_message.is_none());
 
            debug_assert!(!self.inbox_backup.iter().any(|v| v.data_header.target_port == pair.creator_id));
 
        }
 

	
 
        // By now all ports and messages have been transferred. If there are any
 
        // peers that need to be notified about this new component, then we
 
        // initiate the protocol that will notify everyone here.
 
        if created_component_has_remote_peers {
 
            let created_ctx = &component.ctx;
 
            let schedule_entry_id = self.control.add_schedule_entry(created_ctx.id);
 
            for pair in opened_port_id_pairs.iter() {
 
                let port_info = created_ctx.get_port(pair.created_handle);
 
                if port_info.peer_comp_id != creator_ctx.id && port_info.peer_comp_id != created_ctx.id {
 
                    let message = self.control.add_reroute_entry(
 
                        creator_ctx.id, port_info.peer_port_id, port_info.peer_comp_id,
 
                        pair.creator_id, pair.created_id, created_ctx.id,
 
                        schedule_entry_id
 
                    );
 
                    let peer_handle = created_ctx.get_peer_handle(port_info.peer_comp_id);
 
                    let peer_info = created_ctx.get_peer(peer_handle);
 
                    peer_info.handle.send_message(&sched_ctx.runtime, message, true);
 
                }
 
            }
 
        } else {
 
            // Peer can be scheduled immediately
 
            sched_ctx.runtime.enqueue_work(created_key);
 
        }
 
    }
 
}
 

	
 
/// Recursively goes through the value group, attempting to find ports.
 
/// Duplicates will only be added once.
 
pub(crate) fn find_ports_in_value_group(value_group: &ValueGroup, ports: &mut Vec<PortId>) {
 
    // Helper to check a value for a port and recurse if needed.
 
    fn find_port_in_value(group: &ValueGroup, value: &Value, ports: &mut Vec<PortId>) {
 
        match value {
 
            Value::Input(port_id) | Value::Output(port_id) => {
 
                // This is an actual port
 
                let cur_port = PortId(port_id.id);
 
                for prev_port in ports.iter() {
 
                    if *prev_port == cur_port {
 
                        // Already added
 
                        return;
 
                    }
 
                }
 

	
 
                ports.push(cur_port);
 
            },
 
            Value::Array(heap_pos) |
 
            Value::Message(heap_pos) |
 
            Value::String(heap_pos) |
 
            Value::Struct(heap_pos) |
 
            Value::Union(_, heap_pos) => {
 
                // Reference to some dynamic thing which might contain ports,
 
                // so recurse
 
                let heap_region = &group.regions[*heap_pos as usize];
 
                for embedded_value in heap_region {
 
                    find_port_in_value(group, embedded_value, ports);
 
                }
 
            },
 
            _ => {}, // values we don't care about
 
        }
 
    }
 

	
 
    // Clear the ports, then scan all the available values
 
    ports.clear();
 
    for value in &value_group.values {
 
        find_port_in_value(value_group, value, ports);
 
    }
 
}
 

	
 
struct ValueGroupPortIter<'a> {
 
    group: &'a mut ValueGroup,
 
    heap_stack: Vec<(usize, usize)>,
 
    index: usize,
 
}
 

	
 
impl<'a> ValueGroupPortIter<'a> {
 
    fn new(group: &'a mut ValueGroup) -> Self {
 
        return Self{ group, heap_stack: Vec::new(), index: 0 }
 
    }
 
}
 

	
 
struct ValueGroupPortRef {
 
    id: PortId,
 
    heap_pos: Option<usize>, // otherwise: on stack
 
    index: usize,
 
}
 

	
 
impl<'a> Iterator for ValueGroupPortIter<'a> {
 
    type Item = ValueGroupPortRef;
 

	
 
    fn next(&mut self) -> Option<Self::Item> {
 
        // Enter loop that keeps iterating until a port is found
 
        loop {
 
            if let Some(pos) = self.heap_stack.last() {
 
                let (heap_pos, region_index) = *pos;
 
                if region_index >= self.group.regions[heap_pos].len() {
 
                    self.heap_stack.pop();
 
                    continue;
 
                }
 

	
 
                let value = &self.group.regions[heap_pos][region_index];
 
                self.heap_stack.last_mut().unwrap().1 += 1;
 

	
 
                match value {
 
                    Value::Input(id) | Value::Output(id) => {
 
                        let id = PortId(id.id);
 
                        return Some(ValueGroupPortRef{
 
                            id,
 
                            heap_pos: Some(heap_pos),
 
                            index: region_index,
 
                        });
 
                    },
 
                    _ => {},
 
                }
 

	
 
                if let Some(heap_pos) = value.get_heap_pos() {
 
                    self.heap_stack.push((heap_pos as usize, 0));
 
                }
 
            } else {
 
                if self.index >= self.group.values.len() {
 
                    return None;
 
                }
 

	
 
                let value = &mut self.group.values[self.index];
 
                self.index += 1;
 

	
 
                match value {
 
                    Value::Input(id) | Value::Output(id) => {
 
                        let id = PortId(id.id);
 
                        return Some(ValueGroupPortRef{
 
                            id,
 
                            heap_pos: None,
 
                            index: self.index - 1
 
                        });
 
                    },
 
                    _ => {},
 
                }
 

	
 
                // Not a port, check if we need to enter a heap region
 
                if let Some(heap_pos) = value.get_heap_pos() {
 
                    self.heap_stack.push((heap_pos as usize, 0));
 
                } // else: just consider the next value
 
            }
 
        }
 
    }
 
}
 
\ No newline at end of file
src/runtime2/component/component_random.rs
Show inline comments
 
use rand::prelude as random;
 
use rand::RngCore;
 

	
 
use crate::protocol::eval::{ValueGroup, Value};
 
use crate::runtime2::*;
 

	
 
use super::*;
 
use super::component::{
 
    self,
 
    Component, CompExecState, CompScheduling,
 
    CompMode, ExitReason
 
};
 
use super::control_layer::*;
 
use super::consensus::*;
 

	
 
/// TODO: Temporary component to figure out what to do with custom components.
 
///     This component sends random numbers between two u32 limits
 
pub struct ComponentRandomU32 {
 
    // Properties for this specific component
 
    output_port_id: PortId,
 
    random_minimum: u32,
 
    random_maximum: u32,
 
    num_sends: u32,
 
    max_num_sends: u32,
 
    generator: random::ThreadRng,
 
    // Generic state-tracking
 
    exec_state: CompExecState,
 
    did_perform_send: bool, // when in sync mode
 
    control: ControlLayer,
 
    consensus: Consensus,
 
}
 

	
 
impl Component for ComponentRandomU32 {
 
    fn on_creation(&mut self, _id: CompId, _sched_ctx: &SchedulerCtx) {}
 

	
 
    fn on_shutdown(&mut self, sched_ctx: &SchedulerCtx) {}
 

	
 
    fn adopt_message(&mut self, _comp_ctx: &mut CompCtx, _message: DataMessage) {
 
        // Impossible since this component does not have any input ports in its
 
        // signature.
 
        unreachable!();
 
    }
 

	
 
    fn handle_message(&mut self, sched_ctx: &mut SchedulerCtx, comp_ctx: &mut CompCtx, message: Message) {
 
        match message {
 
            Message::Data(_message) => unreachable!(),
 
            Message::Sync(message) => {
 
                let decision = self.consensus.receive_sync_message(sched_ctx, comp_ctx, message);
 
                component::default_handle_sync_decision(sched_ctx, &mut self.exec_state, decision, &mut self.consensus);
 
                component::default_handle_sync_decision(sched_ctx, &mut self.exec_state, comp_ctx, decision, &mut self.consensus);
 
            },
 
            Message::Control(message) => {
 
                if let Err(location_and_message) = component::default_handle_control_message(
 
                    &mut self.exec_state, &mut self.control, &mut self.consensus,
 
                    message, sched_ctx, comp_ctx
 
                ) {
 
                    component::default_handle_error_for_builtin(&mut self.exec_state, sched_ctx, location_and_message);
 
                }
 
            },
 
            Message::Poll => unreachable!(),
 
        }
 
    }
 

	
 
    fn run(&mut self, sched_ctx: &mut SchedulerCtx, comp_ctx: &mut CompCtx) -> CompScheduling {
 
        sched_ctx.log(&format!("Running component ComponentRandomU32 (mode: {:?})", self.exec_state.mode));
 

	
 
        match self.exec_state.mode {
 
            CompMode::BlockedGet | CompMode::BlockedSelect => {
 
                // impossible for this component, no input ports and no select
 
                // blocks
 
                unreachable!();
 
            }
 
            CompMode::NonSync => {
 
                // If in non-sync mode then we check if the arguments make sense
 
                // (at some point in the future, this is just a testing
 
                // component).
 
                if self.random_minimum >= self.random_maximum {
 
                    // Could throw an evaluation error, but lets just panic
 
                    panic!("going to crash 'n burn your system now, please provide valid arguments");
 
                }
 

	
 
                if self.num_sends >= self.max_num_sends {
 
                    self.exec_state.set_as_start_exit(ExitReason::Termination);
 
                } else {
 
                    sched_ctx.log("Entering sync mode");
 
                    self.did_perform_send = false;
 
                    self.consensus.notify_sync_start(comp_ctx);
 
                    self.exec_state.mode = CompMode::Sync;
 
                }
 

	
 
                return CompScheduling::Immediate;
 
            },
 
            CompMode::Sync => {
 
                // This component just sends a single message, then waits until
 
                // consensus has been reached
 
                if !self.did_perform_send {
 
                    sched_ctx.log("Sending random message");
 
                    let mut random = self.generator.next_u32() - self.random_minimum;
 
                    let random_delta = self.random_maximum - self.random_minimum;
 
                    random %= random_delta;
 
                    random += self.random_minimum;
 
                    let value_group = ValueGroup::new_stack(vec![Value::UInt32(random)]);
 

	
 
                    let send_result = component::default_send_data_message(
 
                        &mut self.exec_state, self.output_port_id,
 
                        PortInstruction::NoSource, value_group,
 
                        sched_ctx, &mut self.consensus, comp_ctx
 
                    );
 

	
 
                    if let Err(location_and_message) = send_result {
 
                        component::default_handle_error_for_builtin(&mut self.exec_state, sched_ctx, location_and_message);
 
                        return CompScheduling::Immediate
 
                    } else {
 
                        // Blocked or not, we set `did_perform_send` to true. If
 
                        // blocked then the moment we become unblocked (and are back
 
                        // at the `Sync` mode) we have sent the message.
 
                        let scheduling = send_result.unwrap();
 
                        self.did_perform_send = true;
 
                        self.num_sends += 1;
 
                        return scheduling
 
                    }
 
                } else {
 
                    // Message was sent, finish this sync round
 
                    sched_ctx.log("Waiting for consensus");
 
                    self.exec_state.mode = CompMode::SyncEnd;
 
                    let decision = self.consensus.notify_sync_end_success(sched_ctx, comp_ctx);
 
                    component::default_handle_sync_decision(sched_ctx, &mut self.exec_state, decision, &mut self.consensus);
 
                    component::default_handle_sync_decision(sched_ctx, &mut self.exec_state, comp_ctx, decision, &mut self.consensus);
 
                    return CompScheduling::Requeue;
 
                }
 
            },
 
            CompMode::SyncEnd | CompMode::BlockedPut => return CompScheduling::Sleep,
 
            CompMode::StartExit => return component::default_handle_start_exit(
 
                &mut self.exec_state, &mut self.control, sched_ctx, comp_ctx, &mut self.consensus
 
            ),
 
            CompMode::BusyExit => return component::default_handle_busy_exit(
 
                &mut self.exec_state, &self.control, sched_ctx
 
            ),
 
            CompMode::Exit => return component::default_handle_exit(&self.exec_state),
 
        }
 
    }
 
}
 

	
 
impl ComponentRandomU32 {
 
    pub(crate) fn new(arguments: ValueGroup) -> Self {
 
        debug_assert_eq!(arguments.values.len(), 4);
 
        debug_assert!(arguments.regions.is_empty());
 
        let port_id = component::port_id_from_eval(arguments.values[0].as_port_id());
 
        let minimum = arguments.values[1].as_uint32();
 
        let maximum = arguments.values[2].as_uint32();
 
        let num_sends = arguments.values[3].as_uint32();
 

	
 
        return Self{
 
            output_port_id: port_id,
 
            random_minimum: minimum,
 
            random_maximum: maximum,
 
            num_sends: 0,
 
            max_num_sends: num_sends,
 
            generator: random::thread_rng(),
 
            exec_state: CompExecState::new(),
 
            did_perform_send: false,
 
            control: ControlLayer::default(),
 
            consensus: Consensus::new(),
 
        }
 
    }
 
}
 
\ No newline at end of file
0 comments (0 inline, 0 general)