Implement StructuredCloneData::write.

components/script/dom/bindings/structuredclone.rs

@@ -2,7 +2,15 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+use dom::bindings::error::Fallible;
+use dom::bindings::error::Error::DataClone;
+
+use js::jsapi::JSContext;
+use js::jsapi::{JS_WriteStructuredClone, JS_ClearPendingException};
+use js::jsval::JSVal;
+
 use libc::size_t;
+use std::ptr;
 
 #[allow(raw_pointer_deriving)]
 #[deriving(Copy)]
@@ -10,3 +18,23 @@ pub struct StructuredCloneData {
     pub data: *mut u64,
     pub nbytes: size_t,
 }
+
+impl StructuredCloneData {
+    pub fn write(cx: *mut JSContext, message: JSVal)
+                 -> Fallible<StructuredCloneData> {
+        let mut data = ptr::null_mut();
+        let mut nbytes = 0;
+        let result = unsafe {
+            JS_WriteStructuredClone(cx, message, &mut data, &mut nbytes,
+                                    ptr::null(), ptr::null_mut())
+        };
+        if result == 0 {
+            unsafe { JS_ClearPendingException(cx); }
+            return Err(DataClone);
+        }
+        Ok(StructuredCloneData {
+            data: data,
+            nbytes: nbytes,
+        })
+    }
+}

components/script/dom/dedicatedworkerglobalscope.rs

@@ -9,7 +9,6 @@ use dom::bindings::codegen::Bindings::EventHandlerBinding::EventHandlerNonNull;
 use dom::bindings::codegen::InheritTypes::DedicatedWorkerGlobalScopeDerived;
 use dom::bindings::codegen::InheritTypes::{EventTargetCast, WorkerGlobalScopeCast};
 use dom::bindings::error::ErrorResult;
-use dom::bindings::error::Error::DataClone;
 use dom::bindings::global::GlobalRef;
 use dom::bindings::js::{JSRef, Temporary, RootCollection};
 use dom::bindings::refcounted::LiveDOMReferences;
@@ -29,7 +28,7 @@ use servo_util::task_state;
 use servo_util::task_state::{SCRIPT, IN_WORKER};
 
 use js::glue::JS_STRUCTURED_CLONE_VERSION;
-use js::jsapi::{JSContext, JS_ReadStructuredClone, JS_WriteStructuredClone, JS_ClearPendingException};
+use js::jsapi::{JSContext, JS_ReadStructuredClone};
 use js::jsval::{JSVal, UndefinedValue};
 use js::rust::Cx;
 
@@ -231,23 +230,8 @@ impl<'a> PrivateDedicatedWorkerGlobalScopeHelpers for JSRef<'a, DedicatedWorkerG
 }
 
 impl<'a> DedicatedWorkerGlobalScopeMethods for JSRef<'a, DedicatedWorkerGlobalScope> {
-    #[allow(unsafe_blocks)]
     fn PostMessage(self, cx: *mut JSContext, message: JSVal) -> ErrorResult {
-        let mut data = ptr::null_mut();
+        let data = try!(StructuredCloneData::write(cx, message));
-        let mut nbytes = 0;
-        let result = unsafe {
-            JS_WriteStructuredClone(cx, message, &mut data, &mut nbytes,
-                                    ptr::null(), ptr::null_mut())
-        };
-        if result == 0 {
-            unsafe { JS_ClearPendingException(cx); }
-            return Err(DataClone);
-        }
-        let data = StructuredCloneData {
-            data: data,
-            nbytes: nbytes,
-        };
-
         let worker = self.worker.borrow().as_ref().unwrap().clone();
         self.parent_sender.send(ScriptMsg::RunnableMsg(
             box WorkerMessageHandler::new(worker, data)));

components/script/dom/worker.rs

@@ -7,7 +7,7 @@ use dom::bindings::codegen::Bindings::WorkerBinding::WorkerMethods;
 use dom::bindings::codegen::Bindings::EventHandlerBinding::EventHandlerNonNull;
 use dom::bindings::codegen::InheritTypes::EventTargetCast;
 use dom::bindings::error::{Fallible, ErrorResult};
-use dom::bindings::error::Error::{Syntax, DataClone};
+use dom::bindings::error::Error::Syntax;
 use dom::bindings::global::{GlobalRef, GlobalField};
 use dom::bindings::js::{JSRef, Temporary};
 use dom::bindings::refcounted::Trusted;
@@ -23,7 +23,7 @@ use servo_util::str::DOMString;
 
 use js::glue::JS_STRUCTURED_CLONE_VERSION;
 use js::jsapi::JSContext;
-use js::jsapi::{JS_ReadStructuredClone, JS_WriteStructuredClone, JS_ClearPendingException};
+use js::jsapi::JS_ReadStructuredClone;
 use js::jsval::{JSVal, UndefinedValue};
 use url::UrlParser;
 
@@ -101,23 +101,8 @@ impl Worker {
 }
 
 impl<'a> WorkerMethods for JSRef<'a, Worker> {
-    #[allow(unsafe_blocks)]
     fn PostMessage(self, cx: *mut JSContext, message: JSVal) -> ErrorResult {
-        let mut data = ptr::null_mut();
+        let data = try!(StructuredCloneData::write(cx, message));
-        let mut nbytes = 0;
-        let result = unsafe {
-            JS_WriteStructuredClone(cx, message, &mut data, &mut nbytes,
-                                    ptr::null(), ptr::null_mut())
-        };
-        if result == 0 {
-            unsafe { JS_ClearPendingException(cx); }
-            return Err(DataClone);
-        }
-        let data = StructuredCloneData {
-            data: data,
-            nbytes: nbytes,
-        };
-
         let address = Trusted::new(cx, self, self.global.root().r().script_chan().clone());
         self.sender.send((address, ScriptMsg::DOMMessage(data)));
         Ok(())