gecko/js/xpconnect/public/nsTArrayHelpers.h

/* This Source Code Form is subject to the terms of the Mozilla Public
 * 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/. */

#ifndef __NSTARRAYHELPERS_H__
#define __NSTARRAYHELPERS_H__

#include "jsapi.h"
#include "nsContentUtils.h"
#include "nsTArray.h"

template <class T>
inline nsresult
nsTArrayToJSArray(JSContext* aCx, const nsTArray<T>& aSourceArray,
                  JSObject** aResultArray)
{
  MOZ_ASSERT(aCx);

  JS::Rooted<JSObject*> arrayObj(aCx,
    JS_NewArrayObject(aCx, aSourceArray.Length(), nullptr));
  if (!arrayObj) {
    NS_WARNING("JS_NewArrayObject failed!");
    return NS_ERROR_OUT_OF_MEMORY;
  }

  JS::Rooted<JSObject*> global(aCx, JS::CurrentGlobalOrNull(aCx));
  MOZ_ASSERT(global);

  for (uint32_t index = 0; index < aSourceArray.Length(); index++) {
    nsCOMPtr<nsISupports> obj;
    nsresult rv = aSourceArray[index]->QueryInterface(NS_GET_IID(nsISupports), getter_AddRefs(obj));
    NS_ENSURE_SUCCESS(rv, rv);

    JS::Rooted<JS::Value> wrappedVal(aCx);
    rv = nsContentUtils::WrapNative(aCx, global, obj, wrappedVal.address(),
                                    nullptr, true);
    NS_ENSURE_SUCCESS(rv, rv);

    if (!JS_SetElement(aCx, arrayObj, index, &wrappedVal)) {
      NS_WARNING("JS_SetElement failed!");
      return NS_ERROR_FAILURE;
    }
  }

  if (!JS_FreezeObject(aCx, arrayObj)) {
    NS_WARNING("JS_FreezeObject failed!");
    return NS_ERROR_FAILURE;
  }

  *aResultArray = arrayObj;
  return NS_OK;
}

template <>
inline nsresult
nsTArrayToJSArray<nsString>(JSContext* aCx,
                            const nsTArray<nsString>& aSourceArray,
                            JSObject** aResultArray)
{
  MOZ_ASSERT(aCx);

  JS::Rooted<JSObject*> arrayObj(aCx,
    JS_NewArrayObject(aCx, aSourceArray.Length(), nullptr));
  if (!arrayObj) {
    NS_WARNING("JS_NewArrayObject failed!");
    return NS_ERROR_OUT_OF_MEMORY;
  }

  for (uint32_t index = 0; index < aSourceArray.Length(); index++) {
    JSString* s = JS_NewUCStringCopyN(aCx, aSourceArray[index].BeginReading(),
                                      aSourceArray[index].Length());

    if(!s) {
      NS_WARNING("Memory allocation error!");
      return NS_ERROR_OUT_OF_MEMORY;
    }

    JS::Rooted<JS::Value> wrappedVal(aCx, STRING_TO_JSVAL(s));

    if (!JS_SetElement(aCx, arrayObj, index, &wrappedVal)) {
      NS_WARNING("JS_SetElement failed!");
      return NS_ERROR_FAILURE;
    }
  }

  if (!JS_FreezeObject(aCx, arrayObj)) {
    NS_WARNING("JS_FreezeObject failed!");
    return NS_ERROR_FAILURE;
  }

  *aResultArray = arrayObj;
  return NS_OK;
}

#endif /* __NSTARRAYHELPERS_H__ */