shaka-packager/packager/file/threaded_io_file.h

77 lines
2.1 KiB
C++

// Copyright 2015 Google LLC. All rights reserved.
//
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file or at
// https://developers.google.com/open-source/licenses/bsd
#ifndef PACKAGER_FILE_THREADED_IO_FILE_H_
#define PACKAGER_FILE_THREADED_IO_FILE_H_
#include <atomic>
#include <memory>
#include "absl/synchronization/mutex.h"
#include "packager/file/file.h"
#include "packager/file/file_closer.h"
#include "packager/file/io_cache.h"
namespace shaka {
/// Declaration of class which implements a thread-safe circular buffer.
class ThreadedIoFile : public File {
public:
enum Mode { kInputMode, kOutputMode };
ThreadedIoFile(std::unique_ptr<File, FileCloser> internal_file,
Mode mode,
uint64_t io_cache_size,
uint64_t io_block_size);
/// @name File implementation overrides.
/// @{
bool Close() override;
int64_t Read(void* buffer, uint64_t length) override;
int64_t Write(const void* buffer, uint64_t length) override;
void CloseForWriting() override;
int64_t Size() override;
bool Flush() override;
bool Seek(uint64_t position) override;
bool Tell(uint64_t* position) override;
/// @}
protected:
~ThreadedIoFile() override;
bool Open() override;
private:
// Internal task handler implementation. Will dispatch to either
// |RunInInputMode| or |RunInOutputMode| depending on |mode_|.
void TaskHandler();
void RunInInputMode();
void RunInOutputMode();
void WaitForSignal(absl::Mutex* mutex, bool* condition);
std::unique_ptr<File, FileCloser> internal_file_;
const Mode mode_;
IoCache cache_;
std::vector<uint8_t> io_buffer_;
uint64_t position_;
uint64_t size_;
std::atomic<bool> eof_;
std::atomic<int64_t> internal_file_error_;
absl::Mutex flush_mutex_;
bool flushing_ GUARDED_BY(flush_mutex_);
bool flush_complete_ GUARDED_BY(flush_mutex_);
absl::Mutex task_exited_mutex_;
bool task_exited_ GUARDED_BY(task_exited_mutex_);
DISALLOW_COPY_AND_ASSIGN(ThreadedIoFile);
};
} // namespace shaka
#endif // PACKAGER_FILE_THREADED_IO_FILE_H