1 /* 2 * Copyright 2016 Google Inc. All rights reserved. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include "flatbuffers/util.h" 18 19 namespace flatbuffers { 20 21 bool FileExistsRaw(const char *name) { 22 std::ifstream ifs(name); 23 return ifs.good(); 24 } 25 26 bool LoadFileRaw(const char *name, bool binary, std::string *buf) { 27 if (DirExists(name)) return false; 28 std::ifstream ifs(name, binary ? std::ifstream::binary : std::ifstream::in); 29 if (!ifs.is_open()) return false; 30 if (binary) { 31 // The fastest way to read a file into a string. 32 ifs.seekg(0, std::ios::end); 33 auto size = ifs.tellg(); 34 (*buf).resize(static_cast<size_t>(size)); 35 ifs.seekg(0, std::ios::beg); 36 ifs.read(&(*buf)[0], (*buf).size()); 37 } else { 38 // This is slower, but works correctly on all platforms for text files. 39 std::ostringstream oss; 40 oss << ifs.rdbuf(); 41 *buf = oss.str(); 42 } 43 return !ifs.bad(); 44 } 45 46 static LoadFileFunction g_load_file_function = LoadFileRaw; 47 static FileExistsFunction g_file_exists_function = FileExistsRaw; 48 49 bool LoadFile(const char *name, bool binary, std::string *buf) { 50 assert(g_load_file_function); 51 return g_load_file_function(name, binary, buf); 52 } 53 54 bool FileExists(const char *name) { 55 assert(g_file_exists_function); 56 return g_file_exists_function(name); 57 } 58 59 bool DirExists(const char *name) { 60 #ifdef _WIN32 61 #define flatbuffers_stat _stat 62 #define FLATBUFFERS_S_IFDIR _S_IFDIR 63 #else 64 #define flatbuffers_stat stat 65 #define FLATBUFFERS_S_IFDIR S_IFDIR 66 #endif 67 struct flatbuffers_stat file_info; 68 if (flatbuffers_stat(name, &file_info) != 0) return false; 69 return (file_info.st_mode & FLATBUFFERS_S_IFDIR) != 0; 70 } 71 72 LoadFileFunction SetLoadFileFunction(LoadFileFunction load_file_function) { 73 LoadFileFunction previous_function = g_load_file_function; 74 g_load_file_function = load_file_function ? load_file_function : LoadFileRaw; 75 return previous_function; 76 } 77 78 FileExistsFunction SetFileExistsFunction( 79 FileExistsFunction file_exists_function) { 80 FileExistsFunction previous_function = g_file_exists_function; 81 g_file_exists_function = file_exists_function ? 82 file_exists_function : FileExistsRaw; 83 return previous_function; 84 } 85 86 } // namespace flatbuffers 87
