1 files changed, 111 insertions, 0 deletions
diff --git a/chromium/mojo/embedder/platform_channel_pair_posix.cc b/chromium/mojo/embedder/platform_channel_pair_posix.cc
new file mode 100644
index 00000000000..4eaea474c0b
--- /dev/null
+++ b/chromium/mojo/embedder/platform_channel_pair_posix.cc
@@ -0,0 +1,111 @@
+// 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/embedder/platform_channel_pair.h"
+
+#include <fcntl.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "base/command_line.h"
+#include "base/logging.h"
+#include "base/posix/global_descriptors.h"
+#include "base/strings/string_number_conversions.h"
+#include "build/build_config.h"
+#include "mojo/embedder/platform_handle.h"
+
+namespace mojo {
+namespace embedder {
+
+namespace {
+
+bool IsTargetDescriptorUsed(
+    const base::FileHandleMappingVector& file_handle_mapping,
+    int target_fd) {
+  for (size_t i = 0; i < file_handle_mapping.size(); i++) {
+    if (file_handle_mapping[i].second == target_fd)
+      return true;
+  }
+  return false;
+}
+
+}  // namespace
+
+PlatformChannelPair::PlatformChannelPair() {
+  // Create the Unix domain socket and set the ends to nonblocking.
+  int fds[2];
+  // TODO(vtl): Maybe fail gracefully if |socketpair()| fails.
+  PCHECK(socketpair(AF_UNIX, SOCK_STREAM, 0, fds) == 0);
+  PCHECK(fcntl(fds[0], F_SETFL, O_NONBLOCK) == 0);
+  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;
+  PCHECK(setsockopt(fds[0], SOL_SOCKET, SO_NOSIGPIPE, &no_sigpipe,
+                    sizeof(no_sigpipe)) == 0);
+  PCHECK(setsockopt(fds[1], SOL_SOCKET, SO_NOSIGPIPE, &no_sigpipe,
+                    sizeof(no_sigpipe)) == 0);
+#endif  // defined(OS_MACOSX)
+
+  server_handle_.reset(PlatformHandle(fds[0]));
+  DCHECK(server_handle_.is_valid());
+  client_handle_.reset(PlatformHandle(fds[1]));
+  DCHECK(client_handle_.is_valid());
+}
+
+// static
+ScopedPlatformHandle PlatformChannelPair::PassClientHandleFromParentProcess(
+    const base::CommandLine& command_line) {
+  std::string client_fd_string =
+      command_line.GetSwitchValueASCII(kMojoPlatformChannelHandleSwitch);
+  int client_fd = -1;
+  if (client_fd_string.empty() ||
+      !base::StringToInt(client_fd_string, &client_fd) ||
+      client_fd < base::GlobalDescriptors::kBaseDescriptor) {
+    LOG(ERROR) << "Missing or invalid --" << kMojoPlatformChannelHandleSwitch;
+    return ScopedPlatformHandle();
+  }
+
+  return ScopedPlatformHandle(PlatformHandle(client_fd));
+}
+
+void PlatformChannelPair::PrepareToPassClientHandleToChildProcess(
+    base::CommandLine* command_line,
+    base::FileHandleMappingVector* handle_passing_info) const {
+  DCHECK(command_line);
+  DCHECK(handle_passing_info);
+  // This is an arbitrary sanity check. (Note that this guarantees that the loop
+  // below will terminate sanely.)
+  CHECK_LT(handle_passing_info->size(), 1000u);
+
+  DCHECK(client_handle_.is_valid());
+
+  // Find a suitable FD to map our client handle to in the child process.
+  // This has quadratic time complexity in the size of |*handle_passing_info|,
+  // but |*handle_passing_info| should be very small (usually/often empty).
+  int target_fd = base::GlobalDescriptors::kBaseDescriptor;
+  while (IsTargetDescriptorUsed(*handle_passing_info, target_fd))
+    target_fd++;
+
+  handle_passing_info->push_back(std::pair<int, int>(client_handle_.get().fd,
+                                                     target_fd));
+  // Log a warning if the command line already has the switch, but "clobber" it
+  // anyway, since it's reasonably likely that all the switches were just copied
+  // from the parent.
+  LOG_IF(WARNING, command_line->HasSwitch(kMojoPlatformChannelHandleSwitch))
+      << "Child command line already has switch --"
+      << kMojoPlatformChannelHandleSwitch << "="
+      << command_line->GetSwitchValueASCII(kMojoPlatformChannelHandleSwitch);
+  // (Any existing switch won't actually be removed from the command line, but
+  // the last one appended takes precedence.)
+  command_line->AppendSwitchASCII(kMojoPlatformChannelHandleSwitch,
+                                  base::IntToString(target_fd));
+}
+
+}  // namespace embedder
+}  // namespace mojo