Move async_socket_io_handler.* from media/ to base/

media/audio/async_socket_io_handler_posix.cc

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "media/audio/async_socket_io_handler.h"
-
-#include <fcntl.h>
-
-#include "base/posix/eintr_wrapper.h"
-
-namespace media {
-
-AsyncSocketIoHandler::AsyncSocketIoHandler()
-    : socket_(base::SyncSocket::kInvalidHandle),
-      pending_buffer_(NULL),
-      pending_buffer_len_(0),
-      is_watching_(false) {
-}
-
-AsyncSocketIoHandler::~AsyncSocketIoHandler() {
-  DCHECK(CalledOnValidThread());
-}
-
-void AsyncSocketIoHandler::OnFileCanReadWithoutBlocking(int socket) {
-  DCHECK(CalledOnValidThread());
-  DCHECK_EQ(socket, socket_);
-  DCHECK(!read_complete_.is_null());
-
-  if (pending_buffer_) {
-    int bytes_read = HANDLE_EINTR(read(socket_, pending_buffer_,
-                                       pending_buffer_len_));
-    DCHECK_GE(bytes_read, 0);
-    pending_buffer_ = NULL;
-    pending_buffer_len_ = 0;
-    read_complete_.Run(bytes_read > 0 ? bytes_read : 0);
-  } else {
-    // We're getting notifications that we can read from the socket while
-    // we're not waiting for data.  In order to not starve the message loop,
-    // let's stop watching the fd and restart the watch when Read() is called.
-    is_watching_ = false;
-    socket_watcher_.StopWatchingFileDescriptor();
-  }
-}
-
-bool AsyncSocketIoHandler::Read(char* buffer, int buffer_len) {
-  DCHECK(CalledOnValidThread());
-  DCHECK(!read_complete_.is_null());
-  DCHECK(!pending_buffer_);
-
-  EnsureWatchingSocket();
-
-  int bytes_read = HANDLE_EINTR(read(socket_, buffer, buffer_len));
-  if (bytes_read < 0) {
-    if (errno == EAGAIN) {
-      pending_buffer_ = buffer;
-      pending_buffer_len_ = buffer_len;
-    } else {
-      NOTREACHED() << "read(): " << errno;
-      return false;
-    }
-  } else {
-    read_complete_.Run(bytes_read);
-  }
-  return true;
-}
-
-bool AsyncSocketIoHandler::Initialize(base::SyncSocket::Handle socket,
-                                      const ReadCompleteCallback& callback) {
-  DCHECK_EQ(socket_, base::SyncSocket::kInvalidHandle);
-
-  DetachFromThread();
-
-  socket_ = socket;
-  read_complete_ = callback;
-
-  // SyncSocket is blocking by default, so let's convert it to non-blocking.
-  int value = fcntl(socket, F_GETFL);
-  if (!(value & O_NONBLOCK)) {
-    // Set the socket to be non-blocking so we can do async reads.
-    if (fcntl(socket, F_SETFL, O_NONBLOCK) == -1) {
-      NOTREACHED();
-      return false;
-    }
-  }
-
-  return true;
-}
-
-void AsyncSocketIoHandler::EnsureWatchingSocket() {
-  DCHECK(CalledOnValidThread());
-  if (!is_watching_ && socket_ != base::SyncSocket::kInvalidHandle) {
-    is_watching_ = base::MessageLoopForIO::current()->WatchFileDescriptor(
-        socket_, true, base::MessageLoopForIO::WATCH_READ,
-        &socket_watcher_, this);
-  }
-}
-
-}  // namespace media.