/*! Returns the arguments object of this QScriptContext. The arguments object has properties \c callee (equal to callee()) and \c length (equal to argumentCount()), and properties \c 0, \c 1, ..., argumentCount() - 1 that provide access to the argument values. Initially, property \c P (0 <= \c P < argumentCount()) has the same value as argument(\c P). In the case when \c P is less than the number of formal parameters of the function, \c P shares its value with the corresponding property of the activation object (activationObject()). This means that changing this property changes the corresponding property of the activation object and vice versa. \sa argument(), activationObject() */ QScriptValue QScriptContext::argumentsObject() const { JSC::CallFrame *frame = const_cast<JSC::ExecState*>(QScriptEnginePrivate::frameForContext(this)); QScript::APIShim shim(QScript::scriptEngineFromExec(frame)); if (frame == frame->lexicalGlobalObject()->globalExec()) { // <global> context doesn't have arguments. return an empty object return QScriptEnginePrivate::get(QScript::scriptEngineFromExec(frame))->newObject(); } //for a js function if (frame->codeBlock() && frame->callee()) { if (!QScriptEnginePrivate::hasValidCodeBlockRegister(frame)) { // We have a built-in JS host call. // codeBlock is needed by retrieveArguments(), but since it // contains junk, we would crash. Return an invalid value for now. return QScriptValue(); } JSC::JSValue result = frame->interpreter()->retrieveArguments(frame, JSC::asFunction(frame->callee())); return QScript::scriptEngineFromExec(frame)->scriptValueFromJSCValue(result); } if (frame->callerFrame()->hasHostCallFrameFlag()) { // <eval> context doesn't have arguments. return an empty object return QScriptEnginePrivate::get(QScript::scriptEngineFromExec(frame))->newObject(); } //for a native function if (!frame->optionalCalleeArguments() && QScriptEnginePrivate::hasValidCodeBlockRegister(frame)) { // Make sure we don't go here for host JSFunctions Q_ASSERT(frame->argumentCount() > 0); //we need at least 'this' otherwise we'll crash later JSC::Arguments* arguments = new (&frame->globalData())JSC::Arguments(frame, JSC::Arguments::NoParameters); frame->setCalleeArguments(arguments); } return QScript::scriptEngineFromExec(frame)->scriptValueFromJSCValue(frame->optionalCalleeArguments()); }
/*! \internal */ QScriptContextInfoPrivate::QScriptContextInfoPrivate(const QScriptContext *context) { Q_ASSERT(context); functionType = QScriptContextInfo::NativeFunction; functionMetaIndex = -1; functionStartLineNumber = -1; functionEndLineNumber = -1; scriptId = -1; lineNumber = -1; columnNumber = -1; JSC::CallFrame *frame = const_cast<JSC::CallFrame *>(QScriptEnginePrivate::frameForContext(context)); // Get the line number: //We need to know the context directly up in the backtrace, in order to get the line number, and adjust the global context JSC::CallFrame *rewindContext = QScriptEnginePrivate::get(context->engine())->currentFrame; if (QScriptEnginePrivate::contextForFrame(rewindContext) == context) { //top context frame = rewindContext; //for retreiving the global context's "fake" frame // An agent might have provided the line number. lineNumber = QScript::scriptEngineFromExec(frame)->agentLineNumber; if (lineNumber == -1) lineNumber = QScript::scriptEngineFromExec(frame)->uncaughtExceptionLineNumber; } else { // rewind the stack from the top in order to find the frame from the caller where the returnPC is stored while (rewindContext && QScriptEnginePrivate::contextForFrame(rewindContext->callerFrame()->removeHostCallFrameFlag()) != context) rewindContext = rewindContext->callerFrame()->removeHostCallFrameFlag(); if (rewindContext) { frame = rewindContext->callerFrame()->removeHostCallFrameFlag(); //for retreiving the global context's "fake" frame JSC::Instruction *returnPC = rewindContext->returnPC(); JSC::CodeBlock *codeBlock = frame->codeBlock(); if (returnPC && codeBlock && QScriptEnginePrivate::hasValidCodeBlockRegister(frame)) { #if ENABLE(JIT) JSC::JITCode code = codeBlock->getJITCode(); uintptr_t jitOffset = reinterpret_cast<uintptr_t>(JSC::ReturnAddressPtr(returnPC).value()) - reinterpret_cast<uintptr_t>(code.addressForCall().executableAddress()); // We can only use the JIT code offset if it's smaller than the JIT size; // otherwise calling getBytecodeIndex() is meaningless. if (jitOffset < code.size()) { unsigned bytecodeOffset = codeBlock->getBytecodeIndex(frame, JSC::ReturnAddressPtr(returnPC)); #else unsigned bytecodeOffset = returnPC - codeBlock->instructions().begin(); #endif bytecodeOffset--; //because returnPC is on the next instruction. We want the current one lineNumber = codeBlock->lineNumberForBytecodeOffset(const_cast<JSC::ExecState *>(frame), bytecodeOffset); #if ENABLE(JIT) } #endif } } } // Get the filename and the scriptId: JSC::CodeBlock *codeBlock = frame->codeBlock(); if (codeBlock && QScriptEnginePrivate::hasValidCodeBlockRegister(frame)) { JSC::SourceProvider *source = codeBlock->source(); scriptId = source->asID(); fileName = source->url(); } // Get the others information: JSC::JSObject *callee = frame->callee(); if (callee && callee->inherits(&JSC::InternalFunction::info)) functionName = JSC::asInternalFunction(callee)->name(frame); if (callee && callee->inherits(&JSC::JSFunction::info) && !JSC::asFunction(callee)->isHostFunction()) { functionType = QScriptContextInfo::ScriptFunction; JSC::FunctionExecutable *body = JSC::asFunction(callee)->jsExecutable(); functionStartLineNumber = body->lineNo(); functionEndLineNumber = body->lastLine(); for (size_t i = 0; i < body->parameterCount(); ++i) parameterNames.append(body->parameterName(i)); // ### get the function name from the AST } else if (callee && callee->inherits(&QScript::QtFunction::info)) { functionType = QScriptContextInfo::QtFunction; functionMetaIndex = static_cast<QScript::QtFunction*>(callee)->specificIndex(context); const QMetaObject *meta = static_cast<QScript::QtFunction*>(callee)->metaObject(); if (meta != 0) { QMetaMethod method = meta->method(functionMetaIndex); QList<QByteArray> formals = method.parameterNames(); for (int i = 0; i < formals.count(); ++i) parameterNames.append(QLatin1String(formals.at(i))); } } else if (callee && callee->inherits(&QScript::QtPropertyFunction::info)) { functionType = QScriptContextInfo::QtPropertyFunction; functionMetaIndex = static_cast<QScript::QtPropertyFunction*>(callee)->propertyIndex(); } }