[mojo] Ports EDK

mojo/edk/embedder/platform_channel_pair_posix.cc

 // Copyright 2014 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 "mojo/edk/embedder/platform_channel_pair.h"
 
 #include <fcntl.h>
 #include <stddef.h>
 #include <stdint.h>
 #include <sys/socket.h>
 #include <sys/types.h>
 #include <unistd.h>
 
 #include <limits>
 
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/posix/global_descriptors.h"
 #include "base/rand_util.h"

[Anand Mistry (off Chromium), 2016/01/28 02:26:24]

You can remove since there are no other uses of base::Rand* in here.

 #include "base/strings/string_number_conversions.h"
 #include "build/build_config.h"
 #include "mojo/edk/embedder/platform_handle.h"
 
 #if !defined(SO_PEEK_OFF)
 #define SO_PEEK_OFF 42
 #endif
 
 namespace mojo {
 namespace edk {
@@ skipping 12 matching lines @@
 
 }  // namespace
 
 PlatformChannelPair::PlatformChannelPair(bool client_is_blocking) {
   // Create the Unix domain socket.
   int fds[2];
   // TODO(vtl): Maybe fail gracefully if |socketpair()| fails.
 
   PCHECK(socketpair(AF_UNIX, SOCK_STREAM, 0, fds) == 0);
 
-  // Store a common id in the SO_PEEK_OFF option (which we don't use since we
-  // don't peek) as a way of determining later if two sockets are connected to
-  // each other.
-  int identifier = base::RandInt(std::numeric_limits<int32_t>::min(),
-                                 std::numeric_limits<int32_t>::max());
-  setsockopt(fds[0], SOL_SOCKET, SO_PEEK_OFF, &identifier, sizeof(identifier));
-  setsockopt(fds[1], SOL_SOCKET, SO_PEEK_OFF, &identifier, sizeof(identifier));
-
   // Set the ends to nonblocking.
   PCHECK(fcntl(fds[0], F_SETFL, O_NONBLOCK) == 0);
   if (!client_is_blocking)
     PCHECK(fcntl(fds[1], F_SETFL, O_NONBLOCK) == 0);
 
 #if defined(OS_MACOSX)
   // This turns off |SIGPIPE| when writing to a closed socket (causing it to
   // fail with |EPIPE| instead). On Linux, we have to use |send...()| with
   // |MSG_NOSIGNAL| -- which is not supported on Mac -- instead.
   int no_sigpipe = 1;
@@ skipping 67 matching lines @@
   while (IsTargetDescriptorUsed(*handle_passing_info, target_fd))
     target_fd++;
 
   handle_passing_info->push_back(
       std::pair<int, int>(client_handle_.get().handle, target_fd));
   return base::IntToString(target_fd);
 }
 
 }  // namespace edk
 }  // namespace mojo