C++ CallArgs::length方法代码示例

bool
js::math_clz32(JSContext *cx, unsigned argc, Value *vp)
{
    CallArgs args = CallArgsFromVp(argc, vp);

    if (args.length() == 0) {
        args.rval().setInt32(32);
        return true;
    }

    uint32_t n;
    if (!ToUint32(cx, args[0], &n))
        return false;

    if (n == 0) {
        args.rval().setInt32(32);
        return true;
    }

    args.rval().setInt32(mozilla::CountLeadingZeroes32(n));
    return true;
}

static bool
File(JSContext *cx, unsigned argc, Value *vp)
{
    CallArgs args = CallArgsFromVp(argc, vp);

    if (args.length() == 0) {
        XPCThrower::Throw(NS_ERROR_UNEXPECTED, cx);
        return false;
    }

    nsCOMPtr<nsISupports> native;
    nsresult rv = nsDOMMultipartFile::NewFile(getter_AddRefs(native));
    if (NS_FAILED(rv)) {
        XPCThrower::Throw(rv, cx);
        return false;
    }

    nsCOMPtr<nsIJSNativeInitializer> initializer = do_QueryInterface(native);
    MOZ_ASSERT(initializer);

    rv = initializer->Initialize(nullptr, cx, nullptr, args);
    if (NS_FAILED(rv)) {
        XPCThrower::Throw(rv, cx);
        return false;
    }

    nsXPConnect* xpc = nsXPConnect::XPConnect();
    JSObject* glob = CurrentGlobalOrNull(cx);

    nsCOMPtr<nsIXPConnectJSObjectHolder> holder;
    rv = xpc->WrapNativeToJSVal(cx, glob, native, nullptr,
                                &NS_GET_IID(nsISupports),
                                true, args.rval().address());
    if (NS_FAILED(rv)) {
        XPCThrower::Throw(rv, cx);
        return false;
    }
    return true;
}

bool
X4TypeDescr::call(JSContext *cx, unsigned argc, Value *vp)
{
    CallArgs args = CallArgsFromVp(argc, vp);
    const unsigned LANES = 4;

    if (args.length() < LANES) {
        JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_MORE_ARGS_NEEDED,
                             args.callee().getClass()->name, "3", "s");
        return false;
    }

    double values[LANES];
    for (unsigned i = 0; i < LANES; i++) {
        if (!ToNumber(cx, args[i], &values[i]))
            return false;
    }

    Rooted<X4TypeDescr*> descr(cx, &args.callee().as<X4TypeDescr>());
    Rooted<TypedObject*> result(cx, TypedObject::createZeroed(cx, descr, 0));
    if (!result)
        return false;

    MOZ_ASSERT(!result->owner().isNeutered());
    switch (descr->type()) {
#define STORE_LANES(_constant, _type, _name)                                  \
      case _constant:                                                         \
      {                                                                       \
        _type *mem = reinterpret_cast<_type*>(result->typedMem());            \
        for (unsigned i = 0; i < LANES; i++)                                  \
            mem[i] = ConvertScalar<_type>(values[i]);                         \
        break;                                                                \
      }
      JS_FOR_EACH_X4_TYPE_REPR(STORE_LANES)
#undef STORE_LANES
    }
    args.rval().setObject(*result);
    return true;
}

bool
js::intl_canonicalizeTimeZone(JSContext* cx, unsigned argc, Value* vp)
{
    CallArgs args = CallArgsFromVp(argc, vp);
    MOZ_ASSERT(args.length() == 1);
    MOZ_ASSERT(args[0].isString());

    SharedIntlData& sharedIntlData = cx->runtime()->sharedIntlData.ref();

    // Some time zone names are canonicalized differently by ICU -- handle
    // those first:
    RootedString timeZone(cx, args[0].toString());
    RootedAtom ianaTimeZone(cx);
    if (!sharedIntlData.tryCanonicalizeTimeZoneConsistentWithIANA(cx, timeZone, &ianaTimeZone))
        return false;

    if (ianaTimeZone) {
        cx->markAtom(ianaTimeZone);
        args.rval().setString(ianaTimeZone);
        return true;
    }

    AutoStableStringChars stableChars(cx);
    if (!stableChars.initTwoByte(cx, timeZone))
        return false;

    mozilla::Range<const char16_t> tzchars = stableChars.twoByteRange();

    JSString* str = CallICU(cx, [&tzchars](UChar* chars, uint32_t size, UErrorCode* status) {
        return ucal_getCanonicalTimeZoneID(tzchars.begin().get(), tzchars.length(),
                                           chars, size, nullptr, status);
    });
    if (!str)
        return false;

    args.rval().setString(str);
    return true;
}

/* ES5 15.2.4.6. */
static bool
obj_isPrototypeOf(JSContext* cx, unsigned argc, Value* vp)
{
    CallArgs args = CallArgsFromVp(argc, vp);

    /* Step 1. */
    if (args.length() < 1 || !args[0].isObject()) {
        args.rval().setBoolean(false);
        return true;
    }

    /* Step 2. */
    RootedObject obj(cx, ToObject(cx, args.thisv()));
    if (!obj)
        return false;

    /* Step 3. */
    bool isDelegate;
    if (!IsDelegate(cx, obj, args[0], &isDelegate))
        return false;
    args.rval().setBoolean(isDelegate);
    return true;
}

bool
intrinsic_ParallelSpew(ThreadSafeContext *cx, unsigned argc, Value *vp)
{
    CallArgs args = CallArgsFromVp(argc, vp);
    JS_ASSERT(args.length() == 1);
    JS_ASSERT(args[0].isString());

    AutoCheckCannotGC nogc;
    ScopedThreadSafeStringInspector inspector(args[0].toString());
    if (!inspector.ensureChars(cx, nogc))
        return false;

    ScopedJSFreePtr<char> bytes;
    if (inspector.hasLatin1Chars())
        bytes = JS::CharsToNewUTF8CharsZ(cx, inspector.latin1Range()).c_str();
    else
        bytes = JS::CharsToNewUTF8CharsZ(cx, inspector.twoByteRange()).c_str();

    parallel::Spew(parallel::SpewOps, bytes);

    args.rval().setUndefined();
    return true;
}

/*
 * SetScriptHints(fun, flags): Sets various internal hints to the ion
 * compiler for use when compiling |fun| or calls to |fun|.  Flags
 * should be a dictionary object.
 *
 * The function |fun| should be a self-hosted function (in particular,
 * it *must* be a JS function).
 *
 * Possible flags:
 * - |cloneAtCallsite: true| will hint that |fun| should be cloned
 *   each callsite to improve TI resolution.  This is important for
 *   higher-order functions like |Array.map|.
 */
static JSBool
intrinsic_SetScriptHints(JSContext *cx, unsigned argc, Value *vp)
{
    CallArgs args = CallArgsFromVp(argc, vp);
    JS_ASSERT(args.length() >= 2);
    JS_ASSERT(args[0].isObject() && args[0].toObject().isFunction());
    JS_ASSERT(args[1].isObject());

    RootedFunction fun(cx, args[0].toObject().toFunction());
    RootedScript funScript(cx, fun->nonLazyScript());
    RootedObject flags(cx, &args[1].toObject());

    RootedId id(cx);
    RootedValue propv(cx);

    id = AtomToId(Atomize(cx, "cloneAtCallsite", strlen("cloneAtCallsite")));
    if (!JSObject::getGeneric(cx, flags, flags, id, &propv))
        return false;
    if (ToBoolean(propv))
        funScript->shouldCloneAtCallsite = true;

    return true;
}

bool
CrossCompartmentWrapper::call(JSContext *cx, HandleObject wrapper, const CallArgs &args)
{
    RootedObject wrapped(cx, wrappedObject(wrapper));

    {
        AutoCompartment call(cx, wrapped);

        args.setCallee(ObjectValue(*wrapped));
        if (!cx->compartment->wrap(cx, args.mutableThisv()))
            return false;

        for (size_t n = 0; n < args.length(); ++n) {
            if (!cx->compartment->wrap(cx, args.handleAt(n)))
                return false;
        }

        if (!Wrapper::call(cx, wrapper, args))
            return false;
    }

    return cx->compartment->wrap(cx, args.rval());
}

static bool
WasmTextToBinary(JSContext* cx, unsigned argc, Value* vp)
{
    CallArgs args = CallArgsFromVp(argc, vp);
    RootedObject callee(cx, &args.callee());

    if (args.length() != 1) {
        ReportUsageError(cx, callee, "Wrong number of arguments");
        return false;
    }

    if (!args[0].isString()) {
        ReportUsageError(cx, callee, "First argument must be a String");
        return false;
    }

    AutoStableStringChars twoByteChars(cx);
    if (!twoByteChars.initTwoByte(cx, args[0].toString()))
        return false;

    UniqueChars error;
    wasm::UniqueBytecode bytes = wasm::TextToBinary(twoByteChars.twoByteChars(), &error);
    if (!bytes) {
        JS_ReportErrorNumber(cx, GetErrorMessage, nullptr, JSMSG_WASM_TEXT_FAIL,
                             error.get() ? error.get() : "out of memory");
        return false;
    }

    Rooted<ArrayBufferObject*> buffer(cx, ArrayBufferObject::create(cx, bytes->length()));
    if (!buffer)
        return false;

    memcpy(buffer->dataPointer(), bytes->begin(), bytes->length());

    args.rval().setObject(*buffer);
    return true;
}

bool
js::intl_patternForSkeleton(JSContext* cx, unsigned argc, Value* vp)
{
    CallArgs args = CallArgsFromVp(argc, vp);
    MOZ_ASSERT(args.length() == 2);
    MOZ_ASSERT(args[0].isString());
    MOZ_ASSERT(args[1].isString());

    JSAutoByteString locale(cx, args[0].toString());
    if (!locale)
        return false;

    AutoStableStringChars skeleton(cx);
    if (!skeleton.initTwoByte(cx, args[1].toString()))
        return false;

    mozilla::Range<const char16_t> skelChars = skeleton.twoByteRange();

    UErrorCode status = U_ZERO_ERROR;
    UDateTimePatternGenerator* gen = udatpg_open(IcuLocale(locale.ptr()), &status);
    if (U_FAILURE(status)) {
        intl::ReportInternalError(cx);
        return false;
    }
    ScopedICUObject<UDateTimePatternGenerator, udatpg_close> toClose(gen);

    JSString* str =
        CallICU(cx, [gen, &skelChars](UChar* chars, uint32_t size, UErrorCode* status) {
            return udatpg_getBestPattern(gen, skelChars.begin().get(), skelChars.length(),
                                         chars, size, status);
        });
    if (!str)
        return false;

    args.rval().setString(str);
    return true;
}

MOZ_ALWAYS_INLINE bool
WeakMap_has_impl(JSContext *cx, CallArgs args)
{
    JS_ASSERT(IsWeakMap(args.thisv()));

    if (args.length() < 1) {
        JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_MORE_ARGS_NEEDED,
                             "WeakMap.has", "0", "s");
        return false;
    }
    JSObject *key = GetKeyArg(cx, args);
    if (!key)
        return false;

    if (ObjectValueMap *map = args.thisv().toObject().as<WeakMapObject>().getMap()) {
        if (map->has(key)) {
            args.rval().setBoolean(true);
            return true;
        }
    }

    args.rval().setBoolean(false);
    return true;
}

bool
js::obj_construct(JSContext* cx, unsigned argc, Value* vp)
{
    CallArgs args = CallArgsFromVp(argc, vp);

    RootedObject obj(cx, nullptr);
    if (args.isConstructing() && (&args.newTarget().toObject() != &args.callee())) {
        RootedObject newTarget(cx, &args.newTarget().toObject());
        obj = CreateThis(cx, &PlainObject::class_, newTarget);
        if (!obj)
            return false;
    } else if (args.length() > 0 && !args[0].isNullOrUndefined()) {
        obj = ToObject(cx, args[0]);
        if (!obj)
            return false;
    } else {
        /* Make an object whether this was called with 'new' or not. */
        if (!NewObjectScriptedCall(cx, &obj))
            return false;
    }

    args.rval().setObject(*obj);
    return true;
}

static bool
InternalConst(JSContext *cx, unsigned argc, jsval *vp)
{
    CallArgs args = CallArgsFromVp(argc, vp);
    if (args.length() == 0) {
        JS_ReportError(cx, "the function takes exactly one argument");
        return false;
    }

    JSString *str = ToString(cx, args[0]);
    if (!str)
        return false;
    JSFlatString *flat = JS_FlattenString(cx, str);
    if (!flat)
        return false;

    if (JS_FlatStringEqualsAscii(flat, "INCREMENTAL_MARK_STACK_BASE_CAPACITY")) {
        vp[0] = UINT_TO_JSVAL(js::INCREMENTAL_MARK_STACK_BASE_CAPACITY);
    } else {
        JS_ReportError(cx, "unknown const name");
        return false;
    }
    return true;
}

bool
RilConsumer::PostRILMessage(JSContext* aCx, unsigned aArgc, Value* aVp)
{
  CallArgs args = CallArgsFromVp(aArgc, aVp);

  if (args.length() != 2) {
    JS_ReportError(aCx, "Expecting two arguments with the RIL message");
    return false;
  }

  int clientId = args[0].toInt32();

  if ((ssize_t)sRilConsumers.Length() <= clientId || !sRilConsumers[clientId]) {
    // Probably shutting down.
    return true;
  }

  nsresult rv = sRilConsumers[clientId]->Send(aCx, args);
  if (NS_FAILED(rv)) {
    return false;
  }

  return true;
}

bool
Library::Close(JSContext* cx, unsigned argc, Value* vp)
{
    CallArgs args = CallArgsFromVp(argc, vp);
    JSObject* obj = JS_THIS_OBJECT(cx, vp);
    if (!obj)
        return false;
    if (!IsLibrary(obj)) {
        JS_ReportError(cx, "not a library");
        return false;
    }

    if (args.length() != 0) {
        JS_ReportError(cx, "close doesn't take any arguments");
        return false;
    }

    // delete our internal objects
    UnloadLibrary(obj);
    JS_SetReservedSlot(obj, SLOT_LIBRARY, PrivateValue(nullptr));

    args.rval().setUndefined();
    return true;
}