Split the IPC code into ipc/

This splits the ipc code from the common project.  The 'common' project pulls in
all of webkit, the v8 bindings, skia, googleurl, and a number of other projects
which makes it very difficult to deal with especially for external projects
wanting just to use some of Chromium's infrastructure.  This puts the ipc code
into its top-level ipc/ directory with a dependency only on base.  The common
project depends on the new ipc/ipc.gyp:ipc target so that all projects currently
pulling common in to get the IPC code still have it available.  This mostly
follows agl's pre-gyp attempt to do this which was r13062.

Known issues:
- Currently a number of projects depend on chrome/chrome.gyp:common in order to
use the IPC infrastructure.  Rather than fixing all of these dependencies I have
made common depend on ipc/ipc.gyp:ipc and added "ipc" to the include_rules
section of DEPS so that checkdeps.py doesn't complain.  Over time projects that
need IPC should depend on the IPC project themselves and dependencies on common
removed, although I don't think many projects that need IPC will be able to get
away without common currently.
- ipc/ipc_message_macros.h still has #include "chrome/common/..." inside of a
ipc/ should not refer to files in chrome/... now.  I'm not sure how to resolve
this since it's really an IDE bug
- the named pipe name (windows+linux) and the logging event name (all) + env
variable (posix) refer explicitly to 'Chrome' which somewhat hurts the illusion
of ipc/ being an independent library.  I think this should be examined in a
subsequent, much smaller patch.
- I've eliminated the IPC.SendMsgCount counter since it was implemented in a way
to create a dependency from ipc/ to chrome/common/chrome_counters. This is the
same approach that r13062 took.

http://codereview.chromium.org/155905

(Patch from James Robinson)


git-svn-id: svn://svn.chromium.org/chrome/trunk/src@21342 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 126 insertions, 0 deletions

diff --git a/ipc/ipc_sync_message.cc b/ipc/ipc_sync_message.cc
new file mode 100644
index 0000000..519adb1
--- /dev/null
+++ b/ipc/ipc_sync_message.cc
@@ -0,0 +1,126 @@
+// Copyright (c) 2006-2008 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 "build/build_config.h"
+
+#if defined(OS_WIN)
+#include <windows.h>
+#endif
+#include <stack>
+
+#include "base/logging.h"
+#include "base/waitable_event.h"
+#include "ipc/ipc_sync_message.h"
+
+namespace IPC {
+
+uint32 SyncMessage::next_id_ = 0;
+#define kSyncMessageHeaderSize 4
+
+base::WaitableEvent* dummy_event = new base::WaitableEvent(true, true);
+
+SyncMessage::SyncMessage(
+    int32 routing_id,
+    uint16 type,
+    PriorityValue priority,
+    MessageReplyDeserializer* deserializer)
+    : Message(routing_id, type, priority),
+      deserializer_(deserializer),
+      pump_messages_event_(NULL)
+      {
+  set_sync();
+  set_unblock(true);
+
+  // Add synchronous message data before the message payload.
+  SyncHeader header;
+  header.message_id = ++next_id_;
+  WriteSyncHeader(this, header);
+}
+
+MessageReplyDeserializer* SyncMessage::GetReplyDeserializer() {
+  MessageReplyDeserializer* rv = deserializer_;
+  DCHECK(rv);
+  deserializer_ = NULL;
+  return rv;
+}
+
+void SyncMessage::EnableMessagePumping() {
+  DCHECK(!pump_messages_event_);
+  set_pump_messages_event(dummy_event);
+}
+
+bool SyncMessage::IsMessageReplyTo(const Message& msg, int request_id) {
+  if (!msg.is_reply())
+    return false;
+
+  return GetMessageId(msg) == request_id;
+}
+
+void* SyncMessage::GetDataIterator(const Message* msg) {
+  void* iter = const_cast<char*>(msg->payload());
+  UpdateIter(&iter, kSyncMessageHeaderSize);
+  return iter;
+}
+
+int SyncMessage::GetMessageId(const Message& msg) {
+  if (!msg.is_sync() && !msg.is_reply())
+    return 0;
+
+  SyncHeader header;
+  if (!ReadSyncHeader(msg, &header))
+    return 0;
+
+  return header.message_id;
+}
+
+Message* SyncMessage::GenerateReply(const Message* msg) {
+  DCHECK(msg->is_sync());
+
+  Message* reply = new Message(msg->routing_id(), IPC_REPLY_ID,
+                               msg->priority());
+  reply->set_reply();
+
+  SyncHeader header;
+
+  // use the same message id, but this time reply bit is set
+  header.message_id = GetMessageId(*msg);
+  WriteSyncHeader(reply, header);
+
+  return reply;
+}
+
+bool SyncMessage::ReadSyncHeader(const Message& msg, SyncHeader* header) {
+  DCHECK(msg.is_sync() || msg.is_reply());
+
+  void* iter = NULL;
+  bool result = msg.ReadInt(&iter, &header->message_id);
+  if (!result) {
+    NOTREACHED();
+    return false;
+  }
+
+  return true;
+}
+
+bool SyncMessage::WriteSyncHeader(Message* msg, const SyncHeader& header) {
+  DCHECK(msg->is_sync() || msg->is_reply());
+  DCHECK(msg->payload_size() == 0);
+  bool result = msg->WriteInt(header.message_id);
+  if (!result) {
+    NOTREACHED();
+    return false;
+  }
+
+  // Note: if you add anything here, you need to update kSyncMessageHeaderSize.
+  DCHECK(kSyncMessageHeaderSize == msg->payload_size());
+
+  return true;
+}
+
+
+bool MessageReplyDeserializer::SerializeOutputParameters(const Message& msg) {
+  return SerializeOutputParameters(msg, SyncMessage::GetDataIterator(&msg));
+}
+
+}  // namespace IPC