Begin implementing V8 bindings for Mojo

This CL contains the beginnings of JavaScript bindings for the core Mojo
system. The approach in this CL is to bind as close to the "metal" as possible
so as to self-host as much as possiblem in the VM. I've tried to avoid
retaining any state on the C++ side of the bindings, but I didn't quite succeed
because V8 requires embedders to retain state in order to access the memory
that backs ArrayBuffers.

In this CL, I've added some basic bindings for the symbols exported by core.h.
Specifically, I've created bindings for CreateMessagePipe, Close, Wait,
WaitMany, WriteMessage, and ReadMessage.

R=aa@chromium.org, darin@chromium.org
BUG=317398

Review URL: https://codereview.chromium.org/59153005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@234347 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 39 insertions, 6 deletions

diff --git a/gin/array_buffer.h b/gin/array_buffer.h
index b48a687..a645431 100644
--- a/gin/array_buffer.h
+++ b/gin/array_buffer.h
@@ -8,6 +8,7 @@
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/memory/ref_counted.h"  // For scoped_refptr only!
+#include "gin/converter.h"
 #include "v8/include/v8.h"
 
 namespace gin {
@@ -21,25 +22,57 @@ class ArrayBufferAllocator : public v8::ArrayBuffer::Allocator {
   static ArrayBufferAllocator* SharedInstance();
 };
 
-class BufferView {
+class ArrayBuffer {
  public:
-  BufferView(v8::Isolate* isolate, v8::Handle<v8::ArrayBufferView> view);
-  BufferView(v8::Isolate* isolate, v8::Handle<v8::ArrayBuffer> buffer);
-  ~BufferView();
+  explicit ArrayBuffer(v8::Isolate* isolate);
+  ArrayBuffer(v8::Isolate* isolate, v8::Handle<v8::ArrayBuffer> buffer);
+  ~ArrayBuffer();
 
   void* bytes() const { return bytes_; }
   size_t num_bytes() const { return num_bytes_; }
 
+  v8::Isolate* isolate() const { return isolate_; }
+
  private:
   class Private;
 
-  void Initialize(v8::Isolate* isolate, v8::Handle<v8::ArrayBuffer> buffer);
-
+  v8::Isolate* isolate_;
   scoped_refptr<Private> private_;
   void* bytes_;
   size_t num_bytes_;
 };
 
+template<>
+struct Converter<ArrayBuffer> {
+  static bool FromV8(v8::Handle<v8::Value> val,
+                     ArrayBuffer* out);
+};
+
+class ArrayBufferView {
+ public:
+  explicit ArrayBufferView(v8::Isolate* isolate);
+  ArrayBufferView(v8::Isolate* isolate, v8::Handle<v8::ArrayBufferView> view);
+  ~ArrayBufferView();
+
+  void* bytes() const {
+    return static_cast<uint8_t*>(array_buffer_.bytes()) + offset_;
+  }
+  size_t num_bytes() const { return num_bytes_; }
+
+  v8::Isolate* isolate() const { return array_buffer_.isolate(); }
+
+ private:
+  ArrayBuffer array_buffer_;
+  size_t offset_;
+  size_t num_bytes_;
+};
+
+template<>
+struct Converter<ArrayBufferView> {
+  static bool FromV8(v8::Handle<v8::Value> val,
+                     ArrayBufferView* out);
+};
+
 }  // namespace gin
 
 #endif  // GIN_ARRAY_BUFFER_H_