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/*
* libjingle
* Copyright 2009, Google Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
* EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "talk/base/filelock.h"
#include "talk/base/fileutils.h"
#include "talk/base/logging.h"
#include "talk/base/pathutils.h"
#include "talk/base/stream.h"
namespace talk_base {
FileLock::FileLock(const std::string& path, FileStream* file)
: path_(path), file_(file) {
}
FileLock::~FileLock() {
MaybeUnlock();
}
void FileLock::Unlock() {
LOG_F(LS_INFO);
MaybeUnlock();
}
void FileLock::MaybeUnlock() {
if (file_) {
LOG(LS_INFO) << "Unlocking:" << path_;
file_->Close();
Filesystem::DeleteFile(path_);
file_.reset();
}
}
FileLock* FileLock::TryLock(const std::string& path) {
FileStream* stream = new FileStream();
bool ok = false;
#ifdef WIN32
// Open and lock in a single operation.
ok = stream->OpenShare(path, "a", _SH_DENYRW, NULL);
#else // Linux and OSX
ok = stream->Open(path, "a", NULL) && stream->TryLock();
#endif
if (ok) {
return new FileLock(path, stream);
} else {
// Something failed, either we didn't succeed to open the
// file or we failed to lock it. Anyway remove the heap
// allocated object and then return NULL to indicate failure.
delete stream;
return NULL;
}
}
} // namespace talk_base
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