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/*
* Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include "rtc_base/system/file_wrapper.h"
#include <stddef.h>
#include <cerrno>
#include <cstdint>
#include <string>
#include "absl/strings/string_view.h"
#include "rtc_base/checks.h"
#include "rtc_base/numerics/safe_conversions.h"
#ifdef _WIN32
#include <Windows.h>
#else
#endif
#include <utility>
namespace webrtc {
namespace {
FILE* FileOpen(absl::string_view file_name_utf8, bool read_only, int* error) {
RTC_CHECK_EQ(file_name_utf8.find_first_of('\0'), absl::string_view::npos)
<< "Invalid filename, containing NUL character";
std::string file_name(file_name_utf8);
#if defined(_WIN32)
int len = MultiByteToWideChar(CP_UTF8, 0, file_name.c_str(), -1, nullptr, 0);
std::wstring wstr(len, 0);
MultiByteToWideChar(CP_UTF8, 0, file_name.c_str(), -1, &wstr[0], len);
FILE* file = _wfopen(wstr.c_str(), read_only ? L"rb" : L"wb");
#else
FILE* file = fopen(file_name.c_str(), read_only ? "rb" : "wb");
#endif
if (!file && error) {
*error = errno;
}
return file;
}
} // namespace
// static
FileWrapper FileWrapper::OpenReadOnly(absl::string_view file_name_utf8) {
return FileWrapper(FileOpen(file_name_utf8, true, nullptr));
}
// static
FileWrapper FileWrapper::OpenWriteOnly(absl::string_view file_name_utf8,
int* error /*=nullptr*/) {
return FileWrapper(FileOpen(file_name_utf8, false, error));
}
FileWrapper::FileWrapper(FileWrapper&& other) {
operator=(std::move(other));
}
FileWrapper& FileWrapper::operator=(FileWrapper&& other) {
Close();
file_ = other.file_;
other.file_ = nullptr;
return *this;
}
bool FileWrapper::SeekRelative(int64_t offset) {
RTC_DCHECK(file_);
return fseek(file_, rtc::checked_cast<long>(offset), SEEK_CUR) == 0;
}
bool FileWrapper::SeekTo(int64_t position) {
RTC_DCHECK(file_);
return fseek(file_, rtc::checked_cast<long>(position), SEEK_SET) == 0;
}
long FileWrapper::FileSize() {
if (file_ == nullptr)
return -1;
long original_position = ftell(file_);
if (original_position < 0)
return -1;
int seek_error = fseek(file_, 0, SEEK_END);
if (seek_error)
return -1;
long file_size = ftell(file_);
seek_error = fseek(file_, original_position, SEEK_SET);
if (seek_error)
return -1;
return file_size;
}
bool FileWrapper::Flush() {
RTC_DCHECK(file_);
return fflush(file_) == 0;
}
size_t FileWrapper::Read(void* buf, size_t length) {
RTC_DCHECK(file_);
return fread(buf, 1, length, file_);
}
bool FileWrapper::ReadEof() const {
RTC_DCHECK(file_);
return feof(file_);
}
bool FileWrapper::Write(const void* buf, size_t length) {
RTC_DCHECK(file_);
return fwrite(buf, 1, length, file_) == length;
}
bool FileWrapper::Close() {
if (file_ == nullptr)
return true;
bool success = fclose(file_) == 0;
file_ = nullptr;
return success;
}
FILE* FileWrapper::Release() {
FILE* file = file_;
file_ = nullptr;
return file;
}
} // namespace webrtc
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