Arun Raghavan b5c48b97f6 Bump to WebRTC M131 release
Ongoing fixes and improvements, transient suppressor is gone. Also,
dropping isac because it doesn't seem to be useful, and is just build
system deadweight now.

Upstream references:

  Version: 131.0.6778.200
  WebRTC: 79aff54b0fa9238ce3518dd9eaf9610cd6f22e82
  Chromium: 2a19506ad24af755f2a215a4c61f775393e0db42
2024-12-26 12:55:16 -05:00

115 lines
4.4 KiB
C++

/*
* Copyright (c) 2011 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.
*/
#ifndef RTC_BASE_SYSTEM_FILE_WRAPPER_H_
#define RTC_BASE_SYSTEM_FILE_WRAPPER_H_
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <optional>
#include <string>
#include "absl/strings/string_view.h"
// Implementation that can read (exclusive) or write from/to a file.
namespace webrtc {
// This class is a thin wrapper around FILE*. It's main features are that it
// owns the FILE*, calling fclose on destruction, and that on windows, file
// names passed to the open methods are always treated as utf-8, regardless of
// system code page.
// Most of the methods return only a success/fail indication. When needed, an
// optional argument |int* error| should be added to all methods, in the same
// way as for the OpenWriteOnly methods.
class FileWrapper final {
public:
// Opens a file, in read or write mode. Use the is_open() method on the
// returned object to check if the open operation was successful. On failure,
// and if `error` is non-null, the system errno value is stored at |*error|.
// The file is closed by the destructor.
static FileWrapper OpenReadOnly(absl::string_view file_name_utf8);
static FileWrapper OpenWriteOnly(absl::string_view file_name_utf8,
int* error = nullptr);
FileWrapper() = default;
// Takes over ownership of `file`, closing it on destruction. Calling with
// null `file` is allowed, and results in a FileWrapper with is_open() false.
explicit FileWrapper(FILE* file) : file_(file) {}
~FileWrapper() { Close(); }
// Copying is not supported.
FileWrapper(const FileWrapper&) = delete;
FileWrapper& operator=(const FileWrapper&) = delete;
// Support for move semantics.
FileWrapper(FileWrapper&&);
FileWrapper& operator=(FileWrapper&&);
// Returns true if a file has been opened. If the file is not open, no methods
// but is_open and Close may be called.
bool is_open() const { return file_ != nullptr; }
// Closes the file, and implies Flush. Returns true on success, false if
// writing buffered data fails. On failure, the file is nevertheless closed.
// Calling Close on an already closed file does nothing and returns success.
bool Close();
// Releases and returns the wrapped file without closing it. This call passes
// the ownership of the file to the caller, and the wrapper is no longer
// responsible for closing it. Similarly the previously wrapped file is no
// longer available for the wrapper to use in any aspect.
FILE* Release();
// Write any buffered data to the underlying file. Returns true on success,
// false on write error. Note: Flushing when closing, is not required.
bool Flush();
// Seeks to the beginning of file. Returns true on success, false on failure,
// e.g., if the underlying file isn't seekable.
bool Rewind() { return SeekTo(0); }
// TODO(nisse): The seek functions are used only by the WavReader. If that
// code is demoted to test code, seek functions can be deleted from this
// utility.
// Seek relative to current file position.
bool SeekRelative(int64_t offset);
// Seek to given position.
bool SeekTo(int64_t position);
// Returns the file size or -1 if a size could not be determined.
// (A file size might not exists for non-seekable files or file-like
// objects, for example /dev/tty on unix.)
std::optional<size_t> FileSize();
// Returns number of bytes read. Short count indicates EOF or error.
size_t Read(void* buf, size_t length);
// If the most recent Read() returned a short count, this methods returns true
// if the short count was due to EOF, and false it it was due to some i/o
// error.
bool ReadEof() const;
// Returns true if all data was successfully written (or buffered), or false
// if there was an error. Writing buffered data can fail later, and is
// reported with return value from Flush or Close.
bool Write(const void* buf, size_t length);
private:
FILE* file_ = nullptr;
};
} // namespace webrtc
#endif // RTC_BASE_SYSTEM_FILE_WRAPPER_H_