Implements JS bindings for mojo data pipe.

third_party/WebKit/Source/core/mojo/MojoHandle.cpp

 // Copyright 2017 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 "core/mojo/MojoHandle.h"
 
 #include "bindings/core/v8/ArrayBufferOrArrayBufferView.h"
 #include "bindings/core/v8/ScriptState.h"
 #include "core/dom/DOMArrayBuffer.h"
 #include "core/dom/DOMArrayBufferView.h"
 #include "core/mojo/MojoCreateSharedBufferResult.h"
+#include "core/mojo/MojoDiscardDataOptions.h"
 #include "core/mojo/MojoDuplicateBufferHandleOptions.h"
 #include "core/mojo/MojoMapBufferResult.h"
+#include "core/mojo/MojoReadDataOptions.h"
+#include "core/mojo/MojoReadDataResult.h"
 #include "core/mojo/MojoReadMessageFlags.h"

[yzshen1, 2017/03/07 22:14:00]

Maybe we should also change it to "Options"?

[alokp, 2017/03/08 00:45:35]

Yes - I will make a pass in another patch to make everything consistent.

 #include "core/mojo/MojoReadMessageResult.h"
 #include "core/mojo/MojoWatcher.h"
+#include "core/mojo/MojoWriteDataOptions.h"
+#include "core/mojo/MojoWriteDataResult.h"
 
 // Mojo messages typically do not contain many handles. In fact most
 // messages do not contain any handle. An inline capacity of 4 should avoid
 // heap allocation in vast majority of cases.
 static const size_t kHandleVectorInlineCapacity = 4;
 
 namespace blink {
 
 MojoHandle* MojoHandle::create(mojo::ScopedHandle handle) {
   return new MojoHandle(std::move(handle));
@@ skipping 61 matching lines @@
   for (size_t i = 0; i < numHandles; ++i) {
     handles[i] =
         MojoHandle::create(mojo::MakeScopedHandle(mojo::Handle(rawHandles[i])));
   }
 
   resultDict.setResult(result);
   resultDict.setBuffer(buffer);
   resultDict.setHandles(handles);
 }
 
+void MojoHandle::writeData(const ArrayBufferOrArrayBufferView& buffer,
+                           const MojoWriteDataOptions& optionsDict,
+                           MojoWriteDataResult& resultDict) {
+  MojoWriteDataFlags flags = MOJO_WRITE_DATA_FLAG_NONE;
+  if (optionsDict.allOrNone())
+    flags |= MOJO_WRITE_DATA_FLAG_ALL_OR_NONE;
+
+  const void* elements = nullptr;
+  uint32_t numBytes = 0;
+  if (buffer.isArrayBuffer()) {
+    DOMArrayBuffer* array = buffer.getAsArrayBuffer();
+    elements = array->data();
+    numBytes = array->byteLength();
+  } else {
+    DOMArrayBufferView* view = buffer.getAsArrayBufferView();
+    elements = view->baseAddress();
+    numBytes = view->byteLength();
+  }
+
+  MojoResult result =
+      MojoWriteData(m_handle->value(), elements, &numBytes, flags);
+  resultDict.setResult(result);
+  resultDict.setNumBytes(numBytes);
+}
+
+void MojoHandle::queryData(MojoReadDataResult& resultDict) {
+  uint32_t numBytes = 0;
+  MojoResult result = MojoReadData(m_handle->value(), nullptr, &numBytes,
+                                   MOJO_READ_DATA_FLAG_QUERY);
+  resultDict.setResult(result);
+  resultDict.setNumBytes(numBytes);
+}
+
+void MojoHandle::discardData(unsigned numBytes,
+                             const MojoDiscardDataOptions& optionsDict,
+                             MojoReadDataResult& resultDict) {
+  MojoReadDataFlags flags = MOJO_READ_DATA_FLAG_DISCARD;
+  if (optionsDict.allOrNone())
+    flags |= MOJO_READ_DATA_FLAG_ALL_OR_NONE;
+
+  MojoResult result =
+      MojoReadData(m_handle->value(), nullptr, &numBytes, flags);
+  resultDict.setResult(result);
+  resultDict.setNumBytes(numBytes);
+}
+
+void MojoHandle::readData(ArrayBufferOrArrayBufferView& buffer,
+                          const MojoReadDataOptions& optionsDict,
+                          MojoReadDataResult& resultDict) {
+  MojoReadDataFlags flags = MOJO_READ_DATA_FLAG_NONE;
+  if (optionsDict.allOrNone())
+    flags |= MOJO_READ_DATA_FLAG_ALL_OR_NONE;
+  if (optionsDict.peek())
+    flags |= MOJO_READ_DATA_FLAG_PEEK;
+
+  void* elements = nullptr;
+  unsigned numBytes = 0;
+  if (buffer.isArrayBuffer()) {
+    DOMArrayBuffer* array = buffer.getAsArrayBuffer();
+    elements = array->data();
+    numBytes = array->byteLength();
+  } else {
+    DOMArrayBufferView* view = buffer.getAsArrayBufferView();
+    elements = view->baseAddress();
+    numBytes = view->byteLength();
+  }
+
+  MojoResult result =
+      MojoReadData(m_handle->value(), elements, &numBytes, flags);
+  resultDict.setResult(result);
+  resultDict.setNumBytes(numBytes);
+}
+
 void MojoHandle::mapBuffer(unsigned offset,
                            unsigned numBytes,
                            MojoMapBufferResult& resultDict) {
   void* data = nullptr;
   MojoResult result = MojoMapBuffer(m_handle->value(), offset, numBytes, &data,
                                     MOJO_MAP_BUFFER_FLAG_NONE);
   resultDict.setResult(result);
   if (result == MOJO_RESULT_OK) {
     WTF::ArrayBufferContents::DataHandle dataHandle(data, [](void* buffer) {
       MojoResult result = MojoUnmapBuffer(buffer);
@@ skipping 16 matching lines @@
   mojo::Handle handle;
   MojoResult result = MojoDuplicateBufferHandle(m_handle->value(), &options,
                                                 handle.mutable_value());
   resultDict.setResult(result);
   if (result == MOJO_RESULT_OK) {
     resultDict.setHandle(MojoHandle::create(mojo::MakeScopedHandle(handle)));
   }
 }
 
 }  // namespace blink