Add a Mojo EDK for Chrome that uses one OS pipe per message pipe.

mojo/edk/system/shared_buffer_dispatcher.cc

Index: mojo/edk/system/shared_buffer_dispatcher.cc
diff --git a/third_party/mojo/src/mojo/edk/system/shared_buffer_dispatcher.cc b/mojo/edk/system/shared_buffer_dispatcher.cc
similarity index 89%
copy from third_party/mojo/src/mojo/edk/system/shared_buffer_dispatcher.cc
copy to mojo/edk/system/shared_buffer_dispatcher.cc
index caf8e0b64bfb313975c6cdef71a6a4d3e283ca34..eb6db8d23de05ca61d88a4805ae38f9ae18875af 100644
--- a/third_party/mojo/src/mojo/edk/system/shared_buffer_dispatcher.cc
+++ b/mojo/edk/system/shared_buffer_dispatcher.cc
@@ -8,19 +8,19 @@
 
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
+#include "mojo/edk/embedder/embedder_internal.h"
 #include "mojo/edk/embedder/platform_support.h"
-#include "mojo/edk/system/channel.h"
 #include "mojo/edk/system/configuration.h"
 #include "mojo/edk/system/memory.h"
 #include "mojo/edk/system/options_validation.h"
 #include "mojo/public/c/system/macros.h"
 
 namespace mojo {
-namespace system {
+namespace edk {
 
 namespace {
 
-struct SerializedSharedBufferDispatcher {
+struct MOJO_ALIGNAS(8) SerializedSharedBufferDispatcher {
   size_t num_bytes;
   size_t platform_handle_index;
 };
@@ -63,7 +63,7 @@ MojoResult SharedBufferDispatcher::ValidateCreateOptions(
 
 // static
 MojoResult SharedBufferDispatcher::Create(
-    embedder::PlatformSupport* platform_support,
+    PlatformSupport* platform_support,
     const MojoCreateSharedBufferOptions& /*validated_options*/,
     uint64_t num_bytes,
     scoped_refptr<SharedBufferDispatcher>* result) {
@@ -72,7 +72,7 @@ MojoResult SharedBufferDispatcher::Create(
   if (num_bytes > GetConfiguration().max_shared_memory_num_bytes)
     return MOJO_RESULT_RESOURCE_EXHAUSTED;
 
-  scoped_refptr<embedder::PlatformSharedBuffer> shared_buffer(
+  scoped_refptr<PlatformSharedBuffer> shared_buffer(
       platform_support->CreateSharedBuffer(static_cast<size_t>(num_bytes)));
   if (!shared_buffer)
     return MOJO_RESULT_RESOURCE_EXHAUSTED;
@@ -87,11 +87,9 @@ Dispatcher::Type SharedBufferDispatcher::GetType() const {
 
 // static
 scoped_refptr<SharedBufferDispatcher> SharedBufferDispatcher::Deserialize(
-    Channel* channel,
     const void* source,
     size_t size,
-    embedder::PlatformHandleVector* platform_handles) {
-  DCHECK(channel);
+    PlatformHandleVector* platform_handles) {
 
   if (size != sizeof(SerializedSharedBufferDispatcher)) {
     LOG(ERROR) << "Invalid serialized shared buffer dispatcher (bad size)";
@@ -116,16 +114,16 @@ scoped_refptr<SharedBufferDispatcher> SharedBufferDispatcher::Deserialize(
   }
 
   // Starts off invalid, which is what we want.
-  embedder::PlatformHandle platform_handle;
+  PlatformHandle platform_handle;
   // We take ownership of the handle, so we have to invalidate the one in
   // |platform_handles|.
   std::swap(platform_handle, (*platform_handles)[platform_handle_index]);
 
   // Wrapping |platform_handle| in a |ScopedPlatformHandle| means that it'll be
   // closed even if creation fails.
-  scoped_refptr<embedder::PlatformSharedBuffer> shared_buffer(
-      channel->platform_support()->CreateSharedBufferFromHandle(
-          num_bytes, embedder::ScopedPlatformHandle(platform_handle)));
+  scoped_refptr<PlatformSharedBuffer> shared_buffer(
+      internal::g_platform_support->CreateSharedBufferFromHandle(
+          num_bytes, ScopedPlatformHandle(platform_handle)));
   if (!shared_buffer) {
     LOG(ERROR)
         << "Invalid serialized shared buffer dispatcher (invalid num_bytes?)";
@@ -136,7 +134,7 @@ scoped_refptr<SharedBufferDispatcher> SharedBufferDispatcher::Deserialize(
 }
 
 SharedBufferDispatcher::SharedBufferDispatcher(
-    scoped_refptr<embedder::PlatformSharedBuffer> shared_buffer)
+    scoped_refptr<PlatformSharedBuffer> shared_buffer)
     : shared_buffer_(shared_buffer) {
   DCHECK(shared_buffer_);
 }
@@ -177,14 +175,14 @@ MojoResult SharedBufferDispatcher::ValidateDuplicateOptions(
 }
 
 void SharedBufferDispatcher::CloseImplNoLock() {
-  mutex().AssertHeld();
+  lock().AssertAcquired();
   DCHECK(shared_buffer_);
   shared_buffer_ = nullptr;
 }
 
 scoped_refptr<Dispatcher>
 SharedBufferDispatcher::CreateEquivalentDispatcherAndCloseImplNoLock() {
-  mutex().AssertHeld();
+  lock().AssertAcquired();
   DCHECK(shared_buffer_);
   return CreateInternal(shared_buffer_.Pass());
 }
@@ -192,7 +190,7 @@ SharedBufferDispatcher::CreateEquivalentDispatcherAndCloseImplNoLock() {
 MojoResult SharedBufferDispatcher::DuplicateBufferHandleImplNoLock(
     UserPointer<const MojoDuplicateBufferHandleOptions> options,
     scoped_refptr<Dispatcher>* new_dispatcher) {
-  mutex().AssertHeld();
+  lock().AssertAcquired();
 
   MojoDuplicateBufferHandleOptions validated_options;
   MojoResult result = ValidateDuplicateOptions(options, &validated_options);
@@ -208,8 +206,8 @@ MojoResult SharedBufferDispatcher::MapBufferImplNoLock(
     uint64_t offset,
     uint64_t num_bytes,
     MojoMapBufferFlags flags,
-    scoped_ptr<embedder::PlatformSharedBufferMapping>* mapping) {
-  mutex().AssertHeld();
+    scoped_ptr<PlatformSharedBufferMapping>* mapping) {
+  lock().AssertAcquired();
   DCHECK(shared_buffer_);
 
   if (offset > static_cast<uint64_t>(std::numeric_limits<size_t>::max()))
@@ -231,7 +229,6 @@ MojoResult SharedBufferDispatcher::MapBufferImplNoLock(
 }
 
 void SharedBufferDispatcher::StartSerializeImplNoLock(
-    Channel* /*channel*/,
     size_t* max_size,
     size_t* max_platform_handles) {
   DCHECK(HasOneRef());  // Only one ref => no need to take the lock.
@@ -240,10 +237,9 @@ void SharedBufferDispatcher::StartSerializeImplNoLock(
 }
 
 bool SharedBufferDispatcher::EndSerializeAndCloseImplNoLock(
-    Channel* /*channel*/,
     void* destination,
     size_t* actual_size,
-    embedder::PlatformHandleVector* platform_handles) {
+    PlatformHandleVector* platform_handles) {
   DCHECK(HasOneRef());  // Only one ref => no need to take the lock.
   DCHECK(shared_buffer_);
 
@@ -252,7 +248,7 @@ bool SharedBufferDispatcher::EndSerializeAndCloseImplNoLock(
   // If there's only one reference to |shared_buffer_|, then it's ours (and no
   // one else can make any more references to it), so we can just take its
   // handle.
-  embedder::ScopedPlatformHandle platform_handle(
+  ScopedPlatformHandle platform_handle(
       shared_buffer_->HasOneRef() ? shared_buffer_->PassPlatformHandle()
                                   : shared_buffer_->DuplicatePlatformHandle());
   if (!platform_handle.is_valid()) {
@@ -270,5 +266,6 @@ bool SharedBufferDispatcher::EndSerializeAndCloseImplNoLock(
   return true;
 }
 
-}  // namespace system
+
+}  // namespace edk
 }  // namespace mojo