1 // Protocol Buffers - Google's data interchange format 2 // Copyright 2008 Google Inc. All rights reserved. 3 // https://developers.google.com/protocol-buffers/ 4 // 5 // Redistribution and use in source and binary forms, with or without 6 // modification, are permitted provided that the following conditions are 7 // met: 8 // 9 // * Redistributions of source code must retain the above copyright 10 // notice, this list of conditions and the following disclaimer. 11 // * Redistributions in binary form must reproduce the above 12 // copyright notice, this list of conditions and the following disclaimer 13 // in the documentation and/or other materials provided with the 14 // distribution. 15 // * Neither the name of Google Inc. nor the names of its 16 // contributors may be used to endorse or promote products derived from 17 // this software without specific prior written permission. 18 // 19 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 20 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 21 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 22 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 23 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 24 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 25 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 26 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 27 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 28 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 29 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 30 31 #include <Python.h> 32 33 namespace google { 34 namespace protobuf { 35 namespace python { 36 37 // Version constant. 38 // This is either 0 for python, 1 for CPP V1, 2 for CPP V2. 39 // 40 // 0 is default and is equivalent to 41 // PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION=python 42 // 43 // 1 is set with -DPYTHON_PROTO2_CPP_IMPL_V1 and is equivalent to 44 // PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION=cpp 45 // and 46 // PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION_VERSION=1 47 // 48 // 2 is set with -DPYTHON_PROTO2_CPP_IMPL_V2 and is equivalent to 49 // PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION=cpp 50 // and 51 // PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION_VERSION=2 52 #ifdef PYTHON_PROTO2_CPP_IMPL_V1 53 #if PY_MAJOR_VERSION >= 3 54 #error "PYTHON_PROTO2_CPP_IMPL_V1 is not supported under Python 3." 55 #endif 56 static int kImplVersion = 1; 57 #else 58 #ifdef PYTHON_PROTO2_CPP_IMPL_V2 59 static int kImplVersion = 2; 60 #else 61 #ifdef PYTHON_PROTO2_PYTHON_IMPL 62 static int kImplVersion = 0; 63 #else 64 65 // The defaults are set here. Python 3 uses the fast C++ APIv2 by default. 66 // Python 2 still uses the Python version by default until some compatibility 67 // issues can be worked around. 68 #if PY_MAJOR_VERSION >= 3 69 static int kImplVersion = 2; 70 #else 71 static int kImplVersion = 0; 72 #endif 73 74 #endif // PYTHON_PROTO2_PYTHON_IMPL 75 #endif // PYTHON_PROTO2_CPP_IMPL_V2 76 #endif // PYTHON_PROTO2_CPP_IMPL_V1 77 78 static const char* kImplVersionName = "api_version"; 79 80 static const char* kModuleName = "_api_implementation"; 81 static const char kModuleDocstring[] = 82 "_api_implementation is a module that exposes compile-time constants that\n" 83 "determine the default API implementation to use for Python proto2.\n" 84 "\n" 85 "It complements api_implementation.py by setting defaults using compile-time\n" 86 "constants defined in C, such that one can set defaults at compilation\n" 87 "(e.g. with blaze flag --copt=-DPYTHON_PROTO2_CPP_IMPL_V2)."; 88 89 #if PY_MAJOR_VERSION >= 3 90 static struct PyModuleDef _module = { 91 PyModuleDef_HEAD_INIT, 92 kModuleName, 93 kModuleDocstring, 94 -1, 95 NULL, 96 NULL, 97 NULL, 98 NULL, 99 NULL 100 }; 101 #define INITFUNC PyInit__api_implementation 102 #define INITFUNC_ERRORVAL NULL 103 #else 104 #define INITFUNC init_api_implementation 105 #define INITFUNC_ERRORVAL 106 #endif 107 108 extern "C" { INITFUNC()109 PyMODINIT_FUNC INITFUNC() { 110 #if PY_MAJOR_VERSION >= 3 111 PyObject *module = PyModule_Create(&_module); 112 #else 113 PyObject *module = Py_InitModule3( 114 const_cast<char*>(kModuleName), 115 NULL, 116 const_cast<char*>(kModuleDocstring)); 117 #endif 118 if (module == NULL) { 119 return INITFUNC_ERRORVAL; 120 } 121 122 // Adds the module variable "api_version". 123 if (PyModule_AddIntConstant( 124 module, 125 const_cast<char*>(kImplVersionName), 126 kImplVersion)) 127 #if PY_MAJOR_VERSION < 3 128 return; 129 #else 130 { Py_DECREF(module); return NULL; } 131 132 return module; 133 #endif 134 } 135 } 136 137 } // namespace python 138 } // namespace protobuf 139 } // namespace google 140