1 // Protocol Buffers - Google's data interchange format 2 // Copyright 2008 Google Inc. All rights reserved. 3 // http://code.google.com/p/protobuf/ 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: kenton@google.com (Kenton Varda) 32 33 #ifndef GOOGLE_PROTOBUF_COMPILER_SUBPROCESS_H__ 34 #define GOOGLE_PROTOBUF_COMPILER_SUBPROCESS_H__ 35 36 #ifdef _WIN32 37 #define WIN32_LEAN_AND_MEAN // right... 38 #include <windows.h> 39 #else // _WIN32 40 #include <sys/types.h> 41 #include <unistd.h> 42 #endif // !_WIN32 43 44 #include <string> 45 #include <google/protobuf/stubs/common.h> 46 47 namespace google { 48 namespace protobuf { 49 50 class Message; 51 52 namespace compiler { 53 54 // Utility class for launching sub-processes. 55 class Subprocess { 56 public: 57 Subprocess(); 58 ~Subprocess(); 59 60 enum SearchMode { 61 SEARCH_PATH, // Use PATH environment variable. 62 EXACT_NAME // Program is an exact file name; don't use the PATH. 63 }; 64 65 // Start the subprocess. Currently we don't provide a way to specify 66 // arguments as protoc plugins don't have any. 67 void Start(const string& program, SearchMode search_mode); 68 69 // Serialize the input message and pipe it to the subprocess's stdin, then 70 // close the pipe. Meanwhile, read from the subprocess's stdout and parse 71 // the data into *output. All this is done carefully to avoid deadlocks. 72 // Returns true if successful. On any sort of error, returns false and sets 73 // *error to a description of the problem. 74 bool Communicate(const Message& input, Message* output, string* error); 75 76 #ifdef _WIN32 77 // Given an error code, returns a human-readable error message. This is 78 // defined here so that CommandLineInterface can share it. 79 static string Subprocess::Win32ErrorMessage(DWORD error_code); 80 #endif 81 82 private: 83 #ifdef _WIN32 84 DWORD process_start_error_; 85 HANDLE child_handle_; 86 87 // The file handles for our end of the child's pipes. We close each and 88 // set it to NULL when no longer needed. 89 HANDLE child_stdin_; 90 HANDLE child_stdout_; 91 92 #else // _WIN32 93 pid_t child_pid_; 94 95 // The file descriptors for our end of the child's pipes. We close each and 96 // set it to -1 when no longer needed. 97 int child_stdin_; 98 int child_stdout_; 99 100 #endif // !_WIN32 101 }; 102 103 } // namespace compiler 104 } // namespace protobuf 105 106 } // namespace google 107 #endif // GOOGLE_PROTOBUF_COMPILER_SUBPROCESS_H__ 108