Bug 831107 - Part 1: Allow TCPSocket consumers to receive typed array…

… data without converting it to a byte string first. r=vlad
Brli · Apr 19, 2013 · ecf5004 · ecf5004
1 parent c9bb10b
commit ecf5004
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Showing 3 changed files with 40 additions and 3 deletions.
diff --git a/dom/network/src/TCPSocket.js b/dom/network/src/TCPSocket.js
@@ -576,9 +576,9 @@ TCPSocket.prototype = {
   // nsIStreamListener (Triggered by _inputStreamPump.asyncRead)
   onDataAvailable: function ts_onDataAvailable(request, context, inputStream, offset, count) {
     if (this._binaryType === "arraybuffer") {
-      let ua = this.useWin ? new this.useWin.Uint8Array(count)
-                           : new Uint8Array(count);
-      ua.set(this._inputStreamBinary.readByteArray(count));
+      let buffer = this._inputStreamBinary.readArrayBuffer(count);
+      let constructor = this.useWin ? this.useWin.Uint8Array : Uint8Array;
+      let ua = new constructor(buffer);
       this.callListener("data", ua);
     } else {
       this.callListener("data", this._inputStreamScriptable.read(count));

diff --git a/xpcom/io/nsBinaryStream.cpp b/xpcom/io/nsBinaryStream.cpp
@@ -28,6 +28,9 @@
 #include "nsComponentManagerUtils.h"
 #include "nsIURI.h" // for NS_IURI_IID
 
+#include "jsapi.h"
+#include "jsfriendapi.h"
+
 NS_IMPL_ISUPPORTS3(nsBinaryOutputStream, nsIObjectOutputStream, nsIBinaryOutputStream, nsIOutputStream)
 
 NS_IMETHODIMP
@@ -715,6 +718,30 @@ nsBinaryInputStream::ReadByteArray(uint32_t aLength, uint8_t* *_rval)
     return ReadBytes(aLength, reinterpret_cast<char **>(_rval));
 }
 
+NS_IMETHODIMP
+nsBinaryInputStream::ReadArrayBuffer(uint32_t aLength, JSContext* cx, JS::Value* _rval)
+{
+    JSAutoRequest ar(cx);
+    JS::RootedObject buffer(cx, JS_NewArrayBuffer(cx, aLength));
+    if (!buffer) {
+        return NS_ERROR_FAILURE;
+    }
+    uint8_t* data = JS_GetArrayBufferData(buffer);
+    if (!data) {
+        return NS_ERROR_FAILURE;
+    }
+
+    uint32_t bytesRead;
+    nsresult rv = Read(reinterpret_cast<char*>(data), aLength, &bytesRead);
+    NS_ENSURE_SUCCESS(rv, rv);
+    if (bytesRead != aLength) {
+        return NS_ERROR_FAILURE;
+    }
+
+    *_rval = JS::ObjectValue(*buffer);
+    return NS_OK;
+}
+
 NS_IMETHODIMP
 nsBinaryInputStream::ReadObject(bool aIsStrongRef, nsISupports* *aObject)
 {

diff --git a/xpcom/io/nsIBinaryInputStream.idl b/xpcom/io/nsIBinaryInputStream.idl
@@ -68,6 +68,16 @@ interface nsIBinaryInputStream : nsIInputStream {
      */
     void readByteArray(in uint32_t aLength,
                        [array, size_is(aLength), retval] out uint8_t aBytes);
+
+    /**
+     * Read opaque bytes from the stream, storing the results in an ArrayBuffer.
+     *
+     * @param aLength the number of bytes that must be read
+     *
+     * @throws NS_ERROR_FAILURE if it can't read aLength bytes
+     */
+    [implicit_jscontext]
+    jsval readArrayBuffer(in uint32_t aLength);
 };
 
 %{C++