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

mojo/edk/system/shared_buffer_dispatcher.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 "third_party/mojo/src/mojo/edk/system/shared_buffer_dispatcher.h"
+#include "mojo/edk/system/shared_buffer_dispatcher.h"
 
 #include <limits>
 
 #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/configuration.h"
+#include "mojo/edk/system/options_validation.h"
 #include "mojo/public/c/system/macros.h"
-#include "third_party/mojo/src/mojo/edk/embedder/platform_support.h"
-#include "third_party/mojo/src/mojo/edk/system/channel.h"
-#include "third_party/mojo/src/mojo/edk/system/configuration.h"
-#include "third_party/mojo/src/mojo/edk/system/memory.h"
-#include "third_party/mojo/src/mojo/edk/system/options_validation.h"
 
 namespace mojo {
-namespace system {
+namespace edk {
 
 namespace {
 
-struct SerializedSharedBufferDispatcher {
+struct MOJO_ALIGNAS(8) SerializedSharedBufferDispatcher {
   size_t num_bytes;
   size_t platform_handle_index;
 };
 
 }  // namespace
 
 // static
 const MojoCreateSharedBufferOptions
     SharedBufferDispatcher::kDefaultCreateOptions = {
         static_cast<uint32_t>(sizeof(MojoCreateSharedBufferOptions)),
         MOJO_CREATE_SHARED_BUFFER_OPTIONS_FLAG_NONE};
 
 // static
 MojoResult SharedBufferDispatcher::ValidateCreateOptions(
-    UserPointer<const MojoCreateSharedBufferOptions> in_options,
+    const MojoCreateSharedBufferOptions* in_options,
     MojoCreateSharedBufferOptions* out_options) {
   const MojoCreateSharedBufferOptionsFlags kKnownFlags =
       MOJO_CREATE_SHARED_BUFFER_OPTIONS_FLAG_NONE;
 
   *out_options = kDefaultCreateOptions;
-  if (in_options.IsNull())
+  if (!in_options)
     return MOJO_RESULT_OK;
 
   UserOptionsReader<MojoCreateSharedBufferOptions> reader(in_options);
   if (!reader.is_valid())
     return MOJO_RESULT_INVALID_ARGUMENT;
 
   if (!OPTIONS_STRUCT_HAS_MEMBER(MojoCreateSharedBufferOptions, flags, reader))
     return MOJO_RESULT_OK;
   if ((reader.options().flags & ~kKnownFlags))
     return MOJO_RESULT_UNIMPLEMENTED;
   out_options->flags = reader.options().flags;
 
   // Checks for fields beyond |flags|:
 
   // (Nothing here yet.)
 
   return MOJO_RESULT_OK;
 }
 
 // static
 MojoResult SharedBufferDispatcher::Create(
-    embedder::PlatformSupport* platform_support,
+    PlatformSupport* platform_support,
     const MojoCreateSharedBufferOptions& /*validated_options*/,
     uint64_t num_bytes,
     scoped_refptr<SharedBufferDispatcher>* result) {
   if (!num_bytes)
     return MOJO_RESULT_INVALID_ARGUMENT;
   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;
 
   *result = CreateInternal(shared_buffer.Pass());
   return MOJO_RESULT_OK;
 }
 
 Dispatcher::Type SharedBufferDispatcher::GetType() const {
   return Type::SHARED_BUFFER;
 }
 
 // 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)";
     return nullptr;
   }
 
   const SerializedSharedBufferDispatcher* serialization =
       static_cast<const SerializedSharedBufferDispatcher*>(source);
   size_t num_bytes = serialization->num_bytes;
   size_t platform_handle_index = serialization->platform_handle_index;
 
   if (!num_bytes) {
     LOG(ERROR)
         << "Invalid serialized shared buffer dispatcher (invalid num_bytes)";
     return nullptr;
   }
 
   if (!platform_handles || platform_handle_index >= platform_handles->size()) {
     LOG(ERROR)
         << "Invalid serialized shared buffer dispatcher (missing handles)";
     return nullptr;
   }
 
   // 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?)";
     return nullptr;
   }
 
   return CreateInternal(shared_buffer.Pass());
 }
 
 SharedBufferDispatcher::SharedBufferDispatcher(
-    scoped_refptr<embedder::PlatformSharedBuffer> shared_buffer)
+    scoped_refptr<PlatformSharedBuffer> shared_buffer)
     : shared_buffer_(shared_buffer) {
   DCHECK(shared_buffer_);
 }
 
 SharedBufferDispatcher::~SharedBufferDispatcher() {
 }
 
 // static
 MojoResult SharedBufferDispatcher::ValidateDuplicateOptions(
-    UserPointer<const MojoDuplicateBufferHandleOptions> in_options,
+    const MojoDuplicateBufferHandleOptions* in_options,
     MojoDuplicateBufferHandleOptions* out_options) {
   const MojoDuplicateBufferHandleOptionsFlags kKnownFlags =
       MOJO_DUPLICATE_BUFFER_HANDLE_OPTIONS_FLAG_NONE;
   static const MojoDuplicateBufferHandleOptions kDefaultOptions = {
       static_cast<uint32_t>(sizeof(MojoDuplicateBufferHandleOptions)),
       MOJO_DUPLICATE_BUFFER_HANDLE_OPTIONS_FLAG_NONE};
 
   *out_options = kDefaultOptions;
-  if (in_options.IsNull())
+  if (!in_options)
     return MOJO_RESULT_OK;
 
   UserOptionsReader<MojoDuplicateBufferHandleOptions> reader(in_options);
   if (!reader.is_valid())
     return MOJO_RESULT_INVALID_ARGUMENT;
 
   if (!OPTIONS_STRUCT_HAS_MEMBER(MojoDuplicateBufferHandleOptions, flags,
                                  reader))
     return MOJO_RESULT_OK;
   if ((reader.options().flags & ~kKnownFlags))
     return MOJO_RESULT_UNIMPLEMENTED;
   out_options->flags = reader.options().flags;
 
   // Checks for fields beyond |flags|:
 
   // (Nothing here yet.)
 
   return MOJO_RESULT_OK;
 }
 
 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());
 }
 
 MojoResult SharedBufferDispatcher::DuplicateBufferHandleImplNoLock(
-    UserPointer<const MojoDuplicateBufferHandleOptions> options,
+    const MojoDuplicateBufferHandleOptions* options,
     scoped_refptr<Dispatcher>* new_dispatcher) {
-  mutex().AssertHeld();
+  lock().AssertAcquired();
 
   MojoDuplicateBufferHandleOptions validated_options;
   MojoResult result = ValidateDuplicateOptions(options, &validated_options);
   if (result != MOJO_RESULT_OK)
     return result;
 
   // Note: Since this is "duplicate", we keep our ref to |shared_buffer_|.
   *new_dispatcher = CreateInternal(shared_buffer_);
   return MOJO_RESULT_OK;
 }
 
 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()))
     return MOJO_RESULT_INVALID_ARGUMENT;
   if (num_bytes > static_cast<uint64_t>(std::numeric_limits<size_t>::max()))
     return MOJO_RESULT_INVALID_ARGUMENT;
 
   if (!shared_buffer_->IsValidMap(static_cast<size_t>(offset),
                                   static_cast<size_t>(num_bytes)))
     return MOJO_RESULT_INVALID_ARGUMENT;
 
   DCHECK(mapping);
   *mapping = shared_buffer_->MapNoCheck(static_cast<size_t>(offset),
                                         static_cast<size_t>(num_bytes));
   if (!*mapping)
     return MOJO_RESULT_RESOURCE_EXHAUSTED;
 
   return MOJO_RESULT_OK;
 }
 
 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.
   *max_size = sizeof(SerializedSharedBufferDispatcher);
   *max_platform_handles = 1;
 }
 
 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_);
 
   SerializedSharedBufferDispatcher* serialization =
       static_cast<SerializedSharedBufferDispatcher*>(destination);
   // 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()) {
     shared_buffer_ = nullptr;
     return false;
   }
 
   serialization->num_bytes = shared_buffer_->GetNumBytes();
   serialization->platform_handle_index = platform_handles->size();
   platform_handles->push_back(platform_handle.release());
   *actual_size = sizeof(SerializedSharedBufferDispatcher);
 
   shared_buffer_ = nullptr;
 
   return true;
 }
 
-}  // namespace system
+
+}  // namespace edk
 }  // namespace mojo