| // Copyright 2016 The Fuchsia Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef GARNET_BIN_MEDIAPLAYER_GRAPH_REFS_H_ |
| #define GARNET_BIN_MEDIAPLAYER_GRAPH_REFS_H_ |
| |
| #include <cstddef> |
| |
| namespace media_player { |
| |
| class Graph; |
| class Node; |
| class Input; |
| class Output; |
| class Engine; |
| class InputRef; |
| class OutputRef; |
| |
| // Opaque node pointer used for graph building. |
| class NodeRef { |
| public: |
| NodeRef() {} |
| |
| NodeRef& operator=(std::nullptr_t) { |
| node_ = nullptr; |
| return *this; |
| } |
| |
| // Returns the number of inputs the node has. |
| size_t input_count() const; |
| |
| // Returns a reference to the specified input. |
| InputRef input(size_t index) const; |
| |
| // Returns a reference to the only input. input_count must return 1 for this |
| // call to be valid. |
| InputRef input() const; |
| |
| // Returns the number of outputs the node has. |
| size_t output_count() const; |
| |
| // Returns a reference to the specified output. |
| OutputRef output(size_t index) const; |
| |
| // Returns a reference to the only output. output_count must return 1 for this |
| // call to be valid. |
| OutputRef output() const; |
| |
| // Returns true if the reference refers to a node, false if it's null. |
| explicit operator bool() const { return node_ != nullptr; } |
| |
| Node* GetNode() const { return node_; } |
| |
| bool operator==(const NodeRef& other) const { return node_ == other.node_; } |
| bool operator!=(const NodeRef& other) const { return node_ != other.node_; } |
| |
| private: |
| explicit NodeRef(Node* node) : node_(node) {} |
| |
| Node* node_ = nullptr; |
| |
| friend Graph; |
| friend InputRef; |
| friend OutputRef; |
| friend Engine; |
| }; |
| |
| // Opaque Input pointer used for graph building. |
| class InputRef { |
| public: |
| InputRef() {} |
| |
| InputRef& operator=(std::nullptr_t) { |
| input_ = nullptr; |
| return *this; |
| } |
| |
| // Returns true if the reference refers to an input, false if it's null. |
| explicit operator bool() const { return input_; } |
| |
| // Returns a reference to the node that owns this input. Returns a null |
| // reference if this reference is null. |
| NodeRef node() const; |
| |
| // Indicates whether this input is connected to an output. Calling this method |
| // on a null |InputRef| results in undefined behavior. |
| bool connected() const; |
| |
| // Returns a reference to the output to which this input is connected. Returns |
| // an invalid reference if this input isn't connected to an output. |
| OutputRef mate() const; |
| |
| bool operator==(const InputRef& other) const { |
| return input_ == other.input_; |
| } |
| |
| bool operator!=(const InputRef& other) const { |
| return input_ != other.input_; |
| } |
| |
| private: |
| explicit InputRef(Input* input) : input_(input) {} |
| |
| // Returns the actual input referenced by this object. |
| Input* actual() const { return input_; } |
| |
| Input* input_ = nullptr; |
| |
| friend Graph; |
| friend NodeRef; |
| friend OutputRef; |
| friend Output; |
| friend Engine; |
| }; |
| |
| // Opaque Output pointer used for graph building. |
| class OutputRef { |
| public: |
| OutputRef() {} |
| |
| // Private constructor exposed for testing. |
| explicit OutputRef(Output* output) : output_(output) {} |
| |
| OutputRef& operator=(std::nullptr_t) { |
| output_ = nullptr; |
| return *this; |
| } |
| |
| // Returns true if the reference refers to an output, false if it's null. |
| explicit operator bool() const { return output_; } |
| |
| // Returns a reference to the node that owns this output. Returns a null |
| // reference if this reference is null. |
| NodeRef node() const; |
| |
| // Indicates whether this output is connected to an input. Calling this method |
| // on a null |OutputRef| results in undefined behavior. |
| bool connected() const; |
| |
| // Returns a reference to the input to which this output is connected. Returns |
| // an invalid reference if this output isn't connected to an input. |
| InputRef mate() const; |
| |
| bool operator==(const OutputRef& other) const { |
| return output_ == other.output_; |
| } |
| |
| bool operator!=(const OutputRef& other) const { |
| return output_ != other.output_; |
| } |
| |
| private: |
| // Returns the actual input referenced by this object. |
| Output* actual() const { return output_; }; |
| |
| Output* output_ = nullptr; |
| |
| friend Graph; |
| friend NodeRef; |
| friend InputRef; |
| friend Input; |
| friend Engine; |
| }; |
| |
| } // namespace media_player |
| |
| #endif // GARNET_BIN_MEDIAPLAYER_GRAPH_REFS_H_ |