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 // Author: tibell@google.com (Johan Tibell) 32 33 #ifndef GOOGLE_PROTOBUF_PYTHON_CPP_SCOPED_PYOBJECT_PTR_H__ 34 #define GOOGLE_PROTOBUF_PYTHON_CPP_SCOPED_PYOBJECT_PTR_H__ 35 36 #include <google/protobuf/stubs/common.h> 37 38 #include <Python.h> 39 40 namespace google { 41 class ScopedPyObjectPtr { 42 public: 43 // Constructor. Defaults to initializing with NULL. 44 // There is no way to create an uninitialized ScopedPyObjectPtr. ptr_(p)45 explicit ScopedPyObjectPtr(PyObject* p = NULL) : ptr_(p) { } 46 47 // Destructor. If there is a PyObject object, delete it. ~ScopedPyObjectPtr()48 ~ScopedPyObjectPtr() { 49 Py_XDECREF(ptr_); 50 } 51 52 // Reset. Deletes the current owned object, if any. 53 // Then takes ownership of a new object, if given. 54 // This function must be called with a reference that you own. 55 // this->reset(this->get()) is wrong! 56 // this->reset(this->release()) is OK. 57 PyObject* reset(PyObject* p = NULL) { 58 Py_XDECREF(ptr_); 59 ptr_ = p; 60 return ptr_; 61 } 62 63 // Releases ownership of the object. 64 // The caller now owns the returned reference. release()65 PyObject* release() { 66 PyObject* p = ptr_; 67 ptr_ = NULL; 68 return p; 69 } 70 71 PyObject* operator->() const { 72 assert(ptr_ != NULL); 73 return ptr_; 74 } 75 get()76 PyObject* get() const { return ptr_; } 77 refcnt()78 Py_ssize_t refcnt() const { return Py_REFCNT(ptr_); } 79 inc()80 void inc() const { Py_INCREF(ptr_); } 81 82 // Comparison operators. 83 // These return whether a ScopedPyObjectPtr and a raw pointer 84 // refer to the same object, not just to two different but equal 85 // objects. 86 bool operator==(const PyObject* p) const { return ptr_ == p; } 87 bool operator!=(const PyObject* p) const { return ptr_ != p; } 88 89 private: 90 PyObject* ptr_; 91 92 GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(ScopedPyObjectPtr); 93 }; 94 95 } // namespace google 96 #endif // GOOGLE_PROTOBUF_PYTHON_CPP_SCOPED_PYOBJECT_PTR_H__ 97