C++ JS_NewStringCopyN函数代码示例

FRAGMENT(JSString, simple) {
  js::Rooted<JSString *> empty(cx, JS_NewStringCopyN(cx, NULL, 0));
  js::Rooted<JSString *> x(cx, JS_NewStringCopyN(cx, "x", 1));
  js::Rooted<JSString *> z(cx, JS_NewStringCopyZ(cx, "z"));

  // I expect this will be a non-inlined string.
  js::Rooted<JSString *> stars(cx, JS_NewStringCopyZ(cx,
                                                     "*************************"
                                                     "*************************"
                                                     "*************************"
                                                     "*************************"));

  // This may well be an inlined string.
  js::Rooted<JSString *> xz(cx, JS_ConcatStrings(cx, x, z));

  // This will probably be a rope.
  js::Rooted<JSString *> doubleStars(cx, JS_ConcatStrings(cx, stars, stars));

  breakpoint();

  (void) empty;
  (void) x;
  (void) z;
  (void) stars;
  (void) xz;
  (void) doubleStars;
}

FRAGMENT(JSString, simple) {
  AutoSuppressHazardsForTest noanalysis;

  JS::Rooted<JSString*> empty(cx, JS_NewStringCopyN(cx, nullptr, 0));
  JS::Rooted<JSString*> x(cx, JS_NewStringCopyN(cx, "x", 1));
  JS::Rooted<JSString*> z(cx, JS_NewStringCopyZ(cx, "z"));

  // I expect this will be a non-inlined string.
  JS::Rooted<JSString*> stars(cx,
                              JS_NewStringCopyZ(cx,
                                                "*************************"
                                                "*************************"
                                                "*************************"
                                                "*************************"));

  // This may well be an inlined string.
  JS::Rooted<JSString*> xz(cx, JS_ConcatStrings(cx, x, z));

  // This will probably be a rope.
  JS::Rooted<JSString*> doubleStars(cx, JS_ConcatStrings(cx, stars, stars));

  // Ensure we're not confused by typedefs for pointer types.
  JSString* xRaw = x;

  breakpoint();

  use(empty);
  use(x);
  use(z);
  use(stars);
  use(xz);
  use(doubleStars);
  use(xRaw);
}

static jsval to_javascript_object(JSContext *context, PyObject *value) {
    if (PyString_Check(value)) {
        JSString *obj = JS_NewStringCopyN(context, PyString_AsString(value), PyString_Size(value));
        return STRING_TO_JSVAL(obj);
    } else if (PyUnicode_Check(value)) {
        PyObject *encoded = PyUnicode_AsUTF8String(value);
        JSString *obj = JS_NewStringCopyN(context, PyString_AsString(encoded), PyString_Size(encoded));
        Py_DECREF(encoded);
        return STRING_TO_JSVAL(obj);
    } else if (PyFloat_Check(value)) {
        return DOUBLE_TO_JSVAL(PyFloat_AsDouble(value));
    } else if (PyInt_Check(value)) {
        return INT_TO_JSVAL(PyInt_AsLong(value));
    } else if (PyLong_Check(value)) {
        return INT_TO_JSVAL(PyLong_AsLong(value));
    } else if (PyList_Check(value)) {
        JSObject *obj = JS_NewArrayObject(context, 0, NULL);
        int i;
        for (i = 0; i < PyList_Size(value); i++) {
            jsval item = to_javascript_object(context, PyList_GetItem(value, i));
            JS_SetElement(context, obj, i, &item);
        }
        return OBJECT_TO_JSVAL(obj);
    } else if (PyTuple_Check(value)) {
        JSObject *obj = JS_NewArrayObject(context, 0, NULL);
        int i;
        for (i = 0; i < PyTuple_Size(value); i++) {
            jsval item = to_javascript_object(context, PyTuple_GetItem(value, i));
            JS_SetElement(context, obj, i, &item);
        }
        return OBJECT_TO_JSVAL(obj);
    } else if (PyDict_Check(value)) {
        JSObject *obj = JS_NewObject(context, NULL, NULL, NULL);
        populate_javascript_object(context, obj, value);
        return OBJECT_TO_JSVAL(obj);
    } else if (PyDateTime_Check(value)) {
        JSObject *obj = JS_NewDateObject(context,
            PyDateTime_GET_YEAR(value),
            PyDateTime_GET_MONTH(value) - 1,
            PyDateTime_GET_DAY(value),
            PyDateTime_DATE_GET_HOUR(value),
            PyDateTime_DATE_GET_MINUTE(value),
            PyDateTime_DATE_GET_SECOND(value));
        return OBJECT_TO_JSVAL(obj);
    } else {
        return JSVAL_NULL;
    }
}

void CStdDeserializer::ScriptString(const char* name, JS::MutableHandleString out)
{
#if BYTE_ORDER != LITTLE_ENDIAN
#error TODO: probably need to convert JS strings from little-endian
#endif

	JSContext* cx = m_ScriptInterface.GetContext();
	JSAutoRequest rq(cx);

	bool isLatin1;
	Bool("isLatin1", isLatin1);
	if (isLatin1)
	{
		std::vector<JS::Latin1Char> str;
		ReadStringLatin1(name, str);

		out.set(JS_NewStringCopyN(cx, (const char*)str.data(), str.size()));
		if (!out)
			throw PSERROR_Deserialize_ScriptError("JS_NewStringCopyN failed");
	}
	else
	{
		utf16string str;
		ReadStringUTF16(name, str);

		out.set(JS_NewUCStringCopyN(cx, (const char16_t*)str.data(), str.length()));
		if (!out)
			throw PSERROR_Deserialize_ScriptError("JS_NewUCStringCopyN failed");
	}
}

JSBool JsSite::getAttributeNames(JSContext *cx,JSObject *obj,uintN argc,jsval *argv,jsval *rval)
{
	Site *site = (Site*)JS_GetPrivate(cx,obj);

	JSObject *arr = JS_NewArrayObject(cx,0,NULL);
	if ( arr!=NULL )
	{
		int count=0;

		std::map<std::string,std::string> attributes = site->getAttributes();
		std::map<std::string,std::string>::const_iterator iter;
		for ( iter=attributes.begin(); iter!=attributes.end(); iter++ )
		{
			JSString *str = JS_NewStringCopyN(cx,iter->first.c_str(),iter->first.length());
			jsval element = STRING_TO_JSVAL(str);
			if ( JS_SetElement(cx,arr,count,&element)==JS_TRUE ) {
				count++;
			}
		}

		*rval = OBJECT_TO_JSVAL(arr);
	}

	return JS_TRUE;
}

Atob(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval)
{
    JSString *str;
    if (!argc)
        return JS_TRUE;

    str = JS_ValueToString(cx, argv[0]);
    if (!str)
        return JS_FALSE;

    size_t base64StrLength = JS_GetStringLength(str);
    char *base64Str = JS_GetStringBytes(str);

    PRUint32 bin_dataLength = (PRUint32)base64StrLength;
    if (base64Str[base64StrLength - 1] == '=') {
        if (base64Str[base64StrLength - 2] == '=')
            bin_dataLength -= 2;
        else  
            --bin_dataLength;
    }
    bin_dataLength = (PRUint32)((PRUint64)bin_dataLength * 3) / 4;

    char *bin_data = PL_Base64Decode(base64Str, base64StrLength, nsnull);
    if (!bin_data)
        return JS_FALSE;

    str = JS_NewStringCopyN(cx, bin_data, bin_dataLength);
    PR_Free(bin_data);
    if (!str)
        return JS_FALSE;

    *rval = STRING_TO_JSVAL(str);
    return JS_TRUE;
}

Btoa(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval)
{
    JSString *str;
    if (!argc)
        return JS_TRUE;

    str = JS_ValueToString(cx, argv[0]);
    if (!str)
        return JS_FALSE;

    char *bin_data = JS_GetStringBytes(str);
    size_t bin_dataLength = JS_GetStringLength(str);

    char *base64 = PL_Base64Encode(bin_data, bin_dataLength, nsnull);
    if (!base64)
        return JS_FALSE;

    PRUint32 base64Length = ((bin_dataLength + 2) / 3) * 4;
    str = JS_NewStringCopyN(cx, base64, base64Length);
    PR_Free(base64);
    if (!str)
        return JS_FALSE;

    *rval = STRING_TO_JSVAL(str);
    return JS_TRUE;
}

static JSObject *
add_module_property_to_module_scope (JSContext   *cx,
                                     JSObject    *scope,
                                     const gchar *module_id)
{
  JSObject *module;
  jsval value;
  JSString *st;
  JSAutoCompartment ac(cx, scope);

  /* create the 'module' object */
  module = JS_NewObject (cx, NULL, NULL, NULL);
  g_assert (module != NULL);

  /* add 'module' object as property of scope */
  value = OBJECT_TO_JSVAL (module);
  g_assert (JS_SetProperty (cx, scope, "module", &value));

  /* make 'exports' a permanent and read-only property of scope */
  seal_object_property (cx, scope, "module");

  /* add 'id' property to module object */
  st = JS_NewStringCopyN (cx, module_id, strlen (module_id));
  value = STRING_TO_JSVAL (st);
  g_assert (JS_SetProperty (cx, module, "id", &value));

  /* freeze module object */
  JS_FreezeObject (cx, module);

  return module;
}

static size_t file_callback(void *ptr, size_t size, size_t nmemb, void *data)
{
	register unsigned int realsize = (unsigned int) (size * nmemb);
	struct curl_obj *co = data;
	uintN argc = 0;
	jsval argv[4];


	if (!co) {
		return 0;
	}
	if (co->function) {
		char *ret;
		argv[argc++] = STRING_TO_JSVAL(JS_NewStringCopyN(co->cx, (char *) ptr, realsize));
		if (co->user_data) {
			argv[argc++] = OBJECT_TO_JSVAL(co->user_data);
		}
		JS_ResumeRequest(co->cx, co->saveDepth);
		JS_CallFunction(co->cx, co->obj, co->function, argc, argv, &co->ret);
		co->saveDepth = JS_SuspendRequest(co->cx);

		if ((ret = JS_GetStringBytes(JS_ValueToString(co->cx, co->ret)))) {
			if (!strcmp(ret, "true") || !strcmp(ret, "undefined")) {
				return realsize;
			} else {
				return 0;
			}
		}
	}

	return realsize;
}

template<> jsval ScriptInterface::ToJSVal<std::string>(JSContext* cx, const std::string& val)
{
	JSString* str = JS_NewStringCopyN(cx, val.c_str(), val.length());
	if (str)
		return STRING_TO_JSVAL(str);
	return JSVAL_VOID;
}

static JSBool
jsGetParity( JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval )
{
   jsPort_t *port = (jsPort_t *)JS_GetInstancePrivate( cx, obj, &jsSerialPortClass_, NULL );
   if( port )
   {
      struct termios oldTermState;
      tcgetattr(port->getFd(),&oldTermState);
      char const *parity ;
      if( oldTermState.c_cflag & PARENB )
      {
         if( oldTermState.c_cflag & PARODD )
            parity = "O" ;
         else
            parity = "E" ;
      }
      else
         parity = "N" ;
      
      *rval = STRING_TO_JSVAL( JS_NewStringCopyN( cx, parity, 1 ) );
   }
   else
      *rval = JSVAL_FALSE ;

   return JS_TRUE ;
}

JSAddonId*
NewAddonId(JSContext* cx, const nsACString& id)
{
    JS::RootedString str(cx, JS_NewStringCopyN(cx, id.BeginReading(), id.Length()));
    if (!str)
        return nullptr;
    return JS::NewAddonId(cx, str);
}

JSBool JsSite::getPath(JSContext *cx,JSObject *obj,uintN argc,jsval *argv,jsval *rval)
{
	Site *site = (Site*)JS_GetPrivate(cx,obj);
	JSString *str = JS_NewStringCopyN(cx,site->getPath().c_str(),site->getPath().length());
	*rval = STRING_TO_JSVAL(str);

	return JS_TRUE;
}

template<> void ScriptInterface::ToJSVal<std::string>(JSContext* cx, JS::MutableHandleValue ret, const std::string& val)
{
	JSAutoRequest rq(cx);
	JS::RootedString str(cx, JS_NewStringCopyN(cx, val.c_str(), val.length()));
	if (str)
		ret.setString(str);
	else
		ret.setUndefined();
}

// This is a temporary converter used by nsPlacesImportExportService until
// bug 482911 completes its js rewrite.
jsval
livemarkInfoToJSVal(PRInt64 aId,
                    const nsACString& aGUID,
                    const nsAString& aTitle,
                    PRInt64 aParentId,
                    PRInt32 aIndex,
                    nsCOMPtr<nsIURI>& aFeedURI,
                    nsCOMPtr<nsIURI>& aSiteURI)
{
  nsCOMPtr<nsIXPConnect> xpc = mozilla::services::GetXPConnect();
  NS_ENSURE_TRUE(xpc, JSVAL_NULL);

  nsAXPCNativeCallContext *ncc;
  nsresult rv = xpc->GetCurrentNativeCallContext(&ncc);
  NS_ENSURE_SUCCESS(rv, JSVAL_NULL);
  JSContext *cx = nsnull;
  rv = ncc->GetJSContext(&cx);
  NS_ENSURE_SUCCESS(rv, JSVAL_NULL);
  JSObject *obj = JS_NewObject(cx, NULL, NULL, NULL);
  NS_ENSURE_TRUE(obj, JSVAL_NULL); 

  jsval id;
  NS_ENSURE_TRUE(JS_NewNumberValue(cx, double(aId), &id), JSVAL_NULL);

  JSString* guid = JS_NewStringCopyN(cx, PromiseFlatCString(aGUID).get(),
                                     aGUID.Length());
  NS_ENSURE_TRUE(guid, JSVAL_NULL); 

  JSString* title = JS_NewUCStringCopyN(cx, PromiseFlatString(aTitle).get(),
                                        aTitle.Length());
  NS_ENSURE_TRUE(title, JSVAL_NULL); 

  jsval parentId;
  NS_ENSURE_TRUE(JS_NewNumberValue(cx, double(aParentId), &parentId), JSVAL_NULL);

  jsval feedURI;
  rv = nsContentUtils::WrapNative(cx, JS_GetGlobalForScopeChain(cx),
                                  NS_ISUPPORTS_CAST(nsIURI*, aFeedURI), &feedURI);
  NS_ENSURE_SUCCESS(rv, JSVAL_NULL);

  jsval siteURI;
  rv = nsContentUtils::WrapNative(cx, JS_GetGlobalForScopeChain(cx),
                                  NS_ISUPPORTS_CAST(nsIURI*, aSiteURI), &siteURI);
  NS_ENSURE_SUCCESS(rv, JSVAL_NULL);

  if (!JS_DefineProperty(cx, obj, "id", id, NULL, NULL, JSPROP_ENUMERATE) ||
      !JS_DefineProperty(cx, obj, "guid", STRING_TO_JSVAL(guid), NULL, NULL, JSPROP_ENUMERATE) ||
      !JS_DefineProperty(cx, obj, "title", STRING_TO_JSVAL(title), NULL, NULL, JSPROP_ENUMERATE) ||
      !JS_DefineProperty(cx, obj, "parentId", parentId, NULL, NULL, JSPROP_ENUMERATE) ||
      !JS_DefineProperty(cx, obj, "index", INT_TO_JSVAL(aIndex), NULL, NULL, JSPROP_ENUMERATE) ||
      !JS_DefineProperty(cx, obj, "feedURI", feedURI, NULL, NULL, JSPROP_ENUMERATE) ||
      !JS_DefineProperty(cx, obj, "siteURI", siteURI, NULL, NULL, JSPROP_ENUMERATE)) {
    return JSVAL_NULL;
  }
  return OBJECT_TO_JSVAL(obj);
}