Refactor AppendToFile and WriteFileDescriptor

base/sync_socket_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 "base/sync_socket.h"
 
 #include <errno.h>
 #include <fcntl.h>
 #include <limits.h>
 #include <stdio.h>
@@ skipping 18 matching lines @@
 
 // Writes |length| of |buffer| into |handle|.  Returns the number of bytes
 // written or zero on error.  |length| must be greater than 0.
 size_t SendHelper(SyncSocket::Handle handle,
                   const void* buffer,
                   size_t length) {
   DCHECK_GT(length, 0u);
   DCHECK_LE(length, kMaxMessageLength);
   DCHECK_NE(handle, SyncSocket::kInvalidHandle);
   const char* charbuffer = static_cast<const char*>(buffer);
-  const int len = WriteFileDescriptor(handle, charbuffer, length);
-  return len < 0 ? 0 : static_cast<size_t>(len);
+  return WriteFileDescriptor(handle, charbuffer, length)
+             ? static_cast<size_t>(length)
+             : 0;
 }
 
 bool CloseHandle(SyncSocket::Handle handle) {
   if (handle != SyncSocket::kInvalidHandle && close(handle) < 0) {
     DPLOG(ERROR) << "close";
     return false;
   }
 
   return true;
 }
@@ skipping 185 matching lines @@
   return len;
 }
 
 // static
 bool CancelableSyncSocket::CreatePair(CancelableSyncSocket* socket_a,
                                       CancelableSyncSocket* socket_b) {
   return SyncSocket::CreatePair(socket_a, socket_b);
 }
 
 }  // namespace base