/*

* Copyright 2016 Google Inc. All rights reserved.

*

* Licensed under the Apache License, Version 2.0 (the "License");

* you may not use this file except in compliance with the License.

* You may obtain a copy of the License at

*

* http://www.apache.org/licenses/LICENSE-2.0

*

* Unless required by applicable law or agreed to in writing, software

* distributed under the License is distributed on an "AS IS" BASIS,

* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

* See the License for the specific language governing permissions and

* limitations under the License.

*/

#include "flatbuffers/util.h"

namespace flatbuffers {

bool FileExistsRaw(const char *name) {

std::ifstream ifs(name);

return ifs.good();

}

bool LoadFileRaw(const char *name, bool binary, std::string *buf) {

if (DirExists(name)) return false;

std::ifstream ifs(name, binary ? std::ifstream::binary : std::ifstream::in);

if (!ifs.is_open()) return false;

if (binary) {

// The fastest way to read a file into a string.

ifs.seekg(0, std::ios::end);

auto size = ifs.tellg();

(*buf).resize(static_cast<size_t>(size));

ifs.seekg(0, std::ios::beg);

ifs.read(&(*buf)[0], (*buf).size());

} else {

// This is slower, but works correctly on all platforms for text files.

std::ostringstream oss;

oss << ifs.rdbuf();

*buf = oss.str();

}

return !ifs.bad();

}

static LoadFileFunction g_load_file_function = LoadFileRaw;

static FileExistsFunction g_file_exists_function = FileExistsRaw;

bool LoadFile(const char *name, bool binary, std::string *buf) {

assert(g_load_file_function);

return g_load_file_function(name, binary, buf);

}

bool FileExists(const char *name) {

assert(g_file_exists_function);

return g_file_exists_function(name);

}

bool DirExists(const char *name) {

#ifdef _WIN32

#define flatbuffers_stat _stat

#define FLATBUFFERS_S_IFDIR _S_IFDIR

#else

#define flatbuffers_stat stat

#define FLATBUFFERS_S_IFDIR S_IFDIR

#endif

struct flatbuffers_stat file_info;

if (flatbuffers_stat(name, &file_info) != 0) return false;

return (file_info.st_mode & FLATBUFFERS_S_IFDIR) != 0;

}

LoadFileFunction SetLoadFileFunction(LoadFileFunction load_file_function) {

LoadFileFunction previous_function = g_load_file_function;

g_load_file_function = load_file_function ? load_file_function : LoadFileRaw;

return previous_function;

}

FileExistsFunction SetFileExistsFunction(

FileExistsFunction file_exists_function) {

FileExistsFunction previous_function = g_file_exists_function;

g_file_exists_function = file_exists_function ?

file_exists_function : FileExistsRaw;

return previous_function;

}

} // namespace flatbuffers