1 // Protocol Buffers - Google's data interchange format 2 // Copyright 2008 Google Inc. All rights reserved. 3 // 4 // Use of this source code is governed by a BSD-style 5 // license that can be found in the LICENSE file or at 6 // https://developers.google.com/open-source/licenses/bsd 7 8 #ifndef GOOGLE_PROTOBUF_PYTHON_CPP_MESSAGE_FACTORY_H__ 9 #define GOOGLE_PROTOBUF_PYTHON_CPP_MESSAGE_FACTORY_H__ 10 11 #define PY_SSIZE_T_CLEAN 12 #include <Python.h> 13 14 #include <unordered_map> 15 #include "google/protobuf/descriptor.h" 16 #include "google/protobuf/pyext/descriptor_pool.h" 17 18 namespace google { 19 namespace protobuf { 20 class MessageFactory; 21 22 namespace python { 23 24 // The (meta) type of all Messages classes. 25 struct CMessageClass; 26 27 struct PyMessageFactory { 28 PyObject_HEAD 29 30 // DynamicMessageFactory used to create C++ instances of messages. 31 // This object cache the descriptors that were used, so the DescriptorPool 32 // needs to get rid of it before it can delete itself. 33 // 34 // Note: A C++ MessageFactory is different from the PyMessageFactory. 35 // The C++ one creates messages, when the Python one creates classes. 36 MessageFactory* message_factory; 37 38 // Owned reference to a Python DescriptorPool. 39 // This reference must stay until the message_factory is destructed. 40 PyDescriptorPool* pool; 41 42 // Make our own mapping to retrieve Python classes from C++ descriptors. 43 // 44 // Descriptor pointers stored here are owned by the DescriptorPool above. 45 // Python references to classes are owned by this PyDescriptorPool. 46 typedef std::unordered_map<const Descriptor*, CMessageClass*> 47 ClassesByMessageMap; 48 ClassesByMessageMap* classes_by_descriptor; 49 }; 50 51 extern PyTypeObject PyMessageFactory_Type; 52 53 namespace message_factory { 54 55 // Creates a new MessageFactory instance. 56 PyMessageFactory* NewMessageFactory(PyTypeObject* type, PyDescriptorPool* pool); 57 58 // Registers a new Python class for the given message descriptor. 59 // On error, returns -1 with a Python exception set. 60 int RegisterMessageClass(PyMessageFactory* self, 61 const Descriptor* message_descriptor, 62 CMessageClass* message_class); 63 // Retrieves the Python class registered with the given message descriptor, or 64 // fail with a TypeError. Returns a *borrowed* reference. 65 CMessageClass* GetMessageClass(PyMessageFactory* self, 66 const Descriptor* message_descriptor); 67 // Retrieves the Python class registered with the given message descriptor. 68 // The class is created if not done yet. Returns a *new* reference. 69 CMessageClass* GetOrCreateMessageClass(PyMessageFactory* self, 70 const Descriptor* message_descriptor); 71 } // namespace message_factory 72 73 // Initialize objects used by this module. 74 // On error, returns false with a Python exception set. 75 bool InitMessageFactory(); 76 77 } // namespace python 78 } // namespace protobuf 79 } // namespace google 80 81 #endif // GOOGLE_PROTOBUF_PYTHON_CPP_MESSAGE_FACTORY_H__ 82