Bug 831702 - 0001.Add data size calculation function. r=yoshi.

dom/system/gonk/ril_worker.js

@@ -143,6 +143,55 @@ let Buf = {
 
     // This is the token of last solicited response.
     this.lastSolicitedToken = 0;
+
+    // Queue for storing outgoing override points
+    this.outgoingBufferCalSizeQueue = [];
+  },
+
+  /**
+   * Mark current outgoingIndex as start point for calculation length of data
+   * written to outgoingBuffer.
+   * Mark can be nested for here uses queue to remember marks.
+   *
+   * @param writeFunction
+   *        Function to write data length into outgoingBuffer, this function is
+   *        also used to allocate buffer for data length.
+   *        Raw data size(in Uint8) is provided as parameter calling writeFunction.
+   *        If raw data size is not in proper unit for writing, user can adjust
+   *        the length value in writeFunction before writing.
+   **/
+  startCalOutgoingSize: function startCalOutgoingSize(writeFunction) {
+    let sizeInfo = {index: this.outgoingIndex,
+                    write: writeFunction};
+
+    // Allocate buffer for data lemgtj.
+    writeFunction.call(0);
+
+    // Get size of data length buffer for it is not counted into data size.
+    sizeInfo.size = this.outgoingIndex - sizeInfo.index;
+
+    // Enqueue size calculation information.
+    this.outgoingBufferCalSizeQueue.push(sizeInfo);
+  },
+
+  /**
+   * Calculate data length since last mark, and write it into mark position.
+   **/
+  stopCalOutgoingSize: function stopCalOutgoingSize() {
+    let sizeInfo = this.outgoingBufferCalSizeQueue.pop();
+
+    // Remember current outgoingIndex.
+    let currentOutgoingIndex = this.outgoingIndex;
+    // Calculate data length, in uint8.
+    let writeSize = this.outgoingIndex - sizeInfo.index - sizeInfo.size;
+
+    // Write data length to mark, use same function for allocating buffer to make
+    // sure there is no buffer overloading.
+    this.outgoingIndex = sizeInfo.index;
+    sizeInfo.write(writeSize);
+
+    // Restore outgoingIndex.
+    this.outgoingIndex = currentOutgoingIndex;
   },
 
   /**
@@ -2547,6 +2596,7 @@ let RIL = {
       debug("Stk Envelope " + JSON.stringify(options));
     }
     let token = Buf.newParcel(REQUEST_STK_SEND_ENVELOPE_COMMAND);
+
     let berLen = TLV_DEVICE_ID_SIZE + /* Size of Device Identifier TLV */
                  (options.itemIdentifier ? TLV_ITEM_ID_SIZE : 0) +
                  (options.helpRequested ? TLV_HELP_REQUESTED_SIZE : 0) +