tdesktop/Telegram/SourceFiles/export/output/export_output_file.cpp
2018-06-12 01:02:05 +03:00

55 lines
1.3 KiB
C++

/*
This file is part of Telegram Desktop,
the official desktop application for the Telegram messaging service.
For license and copyright information please follow this link:
https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
*/
#include "export/output/export_output_file.h"
#include <gsl/gsl_util>
namespace Export {
namespace Output {
File::File(const QString &path) : _path(path) {
}
File::Result File::writeBlock(const QByteArray &block) {
const auto result = writeBlockAttempt(block);
if (result != Result::Success) {
_file.clear();
}
return result;
}
File::Result File::writeBlockAttempt(const QByteArray &block) {
if (const auto result = reopen(); result != Result::Success) {
return result;
}
return (_file->write(block) == block.size() && _file->flush())
? Result::Success
: Result::Error;
}
File::Result File::reopen() {
if (_file && _file->isOpen()) {
return Result::Success;
}
_file.emplace(_path);
if (_file->exists()) {
if (_file->size() < _offset) {
return Result::FatalError;
} else if (!_file->resize(_offset)) {
return Result::Error;
}
} else if (_offset > 0) {
return Result::FatalError;
}
return _file->open(QIODevice::Append)
? Result::Success
: Result::Error;
}
} // namespace Output
} // namespace File