// static
void
XPCThrower::Verbosify(XPCCallContext& ccx,
                      char** psz, PRBool own)
{
    char* sz = nsnull;

    if(ccx.HasInterfaceAndMember())
    {
        XPCNativeInterface* iface = ccx.GetInterface();
        jsid id = ccx.GetMember()->GetName();
        JSAutoByteString bytes;
        const char *name = JSID_IS_VOID(id) ? "Unknown" : bytes.encode(ccx, JSID_TO_STRING(id));
        if(!name)
        {
            name = "";
        }
        sz = JS_smprintf("%s [%s.%s]", *psz, iface->GetNameString(), name);
    }

    if(sz)
    {
        if(own)
            JS_smprintf_free(*psz);
        *psz = sz;
    }
}

JSBool XPCDispInterface::Member::GetValue(XPCCallContext& ccx,
                                          XPCNativeInterface * iface, 
                                          jsval * retval) const
{
    // This is a method or attribute - we'll be needing a function object

    // We need to use the safe context for this thread because we don't want
    // to parent the new (and cached forever!) function object to the current
    // JSContext's global object. That would be bad!
    if((mType & RESOLVED) == 0)
    {
        JSContext* cx = ccx.GetSafeJSContext();
        if(!cx)
            return JS_FALSE;

        intN argc;
        JSNative callback;
        // Is this a function or a parameterized getter/setter
        if(IsFunction() || IsParameterizedProperty())
        {
            argc = GetParamCount();
            callback = XPC_IDispatch_CallMethod;
        }
        else
        {
            argc = 0;
            callback = XPC_IDispatch_GetterSetter;
        }

        JSFunction *fun = JS_NewFunctionById(cx, callback, argc, 0, nsnull, mName);
        if(!fun)
            return JS_FALSE;

        JSObject* funobj = JS_GetFunctionObject(fun);
        if(!funobj)
            return JS_FALSE;

        // Store ourselves and our native interface within the JSObject
        if(!JS_SetReservedSlot(ccx, funobj, 0, PRIVATE_TO_JSVAL((void *) this)))
            return JS_FALSE;

        if(!JS_SetReservedSlot(ccx, funobj, 1, PRIVATE_TO_JSVAL(iface)))
            return JS_FALSE;

        {   // scoped lock
            XPCAutoLock lock(ccx.GetRuntime()->GetMapLock());
            const_cast<Member*>(this)->mVal = OBJECT_TO_JSVAL(funobj);
            const_cast<Member*>(this)->mType |= RESOLVED;
        }
    }
    *retval = mVal;
    return JS_TRUE;
}

// static
void
XPCWrappedNativeScope::TraverseScopes(XPCCallContext& ccx)
{
    // Hold the lock throughout.
    XPCAutoLock lock(ccx.GetRuntime()->GetMapLock());

    for(XPCWrappedNativeScope* cur = gScopes; cur; cur = cur->mNext)
        if(cur->mGlobalJSObject && cur->mScriptObjectPrincipal)
        {
            ccx.GetXPConnect()->RecordTraversal(cur->mGlobalJSObject,
                                                cur->mScriptObjectPrincipal);
        }
}

bool
xpc_qsUnwrapThisFromCcxImpl(XPCCallContext &ccx,
                            const nsIID &iid,
                            void **ppThis,
                            nsISupports **pThisRef,
                            jsval *vp)
{
    nsISupports *native = ccx.GetIdentityObject();
    if (!native)
        return xpc_qsThrow(ccx.GetJSContext(), NS_ERROR_XPC_HAS_BEEN_SHUTDOWN);

    RootedObject obj(ccx, ccx.GetFlattenedJSObject());
    nsresult rv = getNative(native, obj, iid, ppThis, pThisRef, vp);
    if (NS_FAILED(rv))
        return xpc_qsThrow(ccx.GetJSContext(), rv);
    return true;
}

void
XPCWrappedNativeScope::SetGlobal(XPCCallContext& ccx, JSObject* aGlobal,
                                 nsISupports* aNative)
{
    // We allow for calling this more than once. This feature is used by
    // nsXPConnect::InitClassesWithNewWrappedGlobal.

    mGlobalJSObject = aGlobal;
    mScriptObjectPrincipal = nsnull;

    // Try to find the native global object. If we didn't receive it explicitly,
    // we might be able to find it in the private slot.
    nsISupports *native;
    if (aNative) {
        native = aNative;
    } else {
        const JSClass *jsClass = js::GetObjectJSClass(aGlobal);
        nsISupports *priv;
        if (!(~jsClass->flags & (JSCLASS_HAS_PRIVATE |
                                 JSCLASS_PRIVATE_IS_NSISUPPORTS))) {
            // Our global has an nsISupports native pointer.  Let's
            // see whether it's what we want.
            priv = static_cast<nsISupports*>(xpc_GetJSPrivate(aGlobal));
        } else if ((jsClass->flags & JSCLASS_IS_DOMJSCLASS) &&
                   bindings::DOMJSClass::FromJSClass(jsClass)->mDOMObjectIsISupports) {
            priv = bindings::UnwrapDOMObject<nsISupports>(aGlobal, jsClass);
        } else {
            priv = nsnull;
        }
        nsCOMPtr<nsIXPConnectWrappedNative> wn = do_QueryInterface(priv);
        if (wn)
            native = static_cast<XPCWrappedNative*>(wn.get())->GetIdentityObject();
        else
            native = priv;
    }

    // Now init our script object principal, if the new global has one.
    nsCOMPtr<nsIScriptObjectPrincipal> sop = do_QueryInterface(native);
    mScriptObjectPrincipal = sop;

    // Lookup 'globalObject.Object.prototype' for our wrapper's proto
    JSObject *objectPrototype =
        JS_GetObjectPrototype(ccx.GetJSContext(), aGlobal);
    if (objectPrototype)
        mPrototypeJSObject = objectPrototype;
    else
        NS_ERROR("Can't get globalObject.Object.prototype");

    // Clear the no helper wrapper prototype object so that a new one
    // gets created if needed.
    mPrototypeNoHelper = nsnull;
}

// static
void
XPCThrower::Verbosify(XPCCallContext& ccx,
                      char** psz, PRBool own)
{
    char* sz = nsnull;

    if(ccx.HasInterfaceAndMember())
    {
        XPCNativeInterface* iface = ccx.GetInterface();
#ifdef XPC_IDISPATCH_SUPPORT
        NS_ASSERTION(ccx.GetIDispatchMember() == nsnull || 
                        ccx.GetMember() == nsnull,
                     "Both IDispatch member and regular XPCOM member "
                     "were set in XPCCallContext");
        char const * name;
        if(ccx.GetIDispatchMember())
        {
            XPCDispInterface::Member * member = 
                reinterpret_cast<XPCDispInterface::Member*>(ccx.GetIDispatchMember());
            if(member && JSVAL_IS_STRING(member->GetName()))
            {
                name = JS_GetStringBytes(JSVAL_TO_STRING(member->GetName()));
            }
            else
                name = "Unknown";
        }
        else
            name = iface->GetMemberName(ccx, ccx.GetMember());
        sz = JS_smprintf("%s [%s.%s]",
                         *psz,
                         iface->GetNameString(),
                         name);
#else
        sz = JS_smprintf("%s [%s.%s]",
                         *psz,
                         iface->GetNameString(),
                         iface->GetMemberName(ccx, ccx.GetMember()));
#endif
    }

    if(sz)
    {
        if(own)
            JS_smprintf_free(*psz);
        *psz = sz;
    }
}

static bool
ToStringGuts(XPCCallContext& ccx)
{
    char* sz;
    XPCWrappedNative* wrapper = ccx.GetWrapper();

    if (wrapper)
        sz = wrapper->ToString(ccx.GetTearOff());
    else
        sz = JS_smprintf("[xpconnect wrapped native prototype]");

    if (!sz) {
        JS_ReportOutOfMemory(ccx);
        return false;
    }

    JSString* str = JS_NewStringCopyZ(ccx, sz);
    JS_smprintf_free(sz);
    if (!str)
        return false;

    ccx.SetRetVal(JS::StringValue(str));
    return true;
}

// static
void
XPCThrower::Verbosify(XPCCallContext& ccx,
                      char** psz, PRBool own)
{
    char* sz = nsnull;

    if(ccx.HasInterfaceAndMember())
    {
        XPCNativeInterface* iface = ccx.GetInterface();
        jsid id = JSID_VOID;
#ifdef XPC_IDISPATCH_SUPPORT
        NS_ASSERTION(ccx.GetIDispatchMember() == nsnull || 
                        ccx.GetMember() == nsnull,
                     "Both IDispatch member and regular XPCOM member "
                     "were set in XPCCallContext");
        if(ccx.GetIDispatchMember())
        {
            XPCDispInterface::Member * member = 
                reinterpret_cast<XPCDispInterface::Member*>(ccx.GetIDispatchMember());
            if(member && JSID_IS_STRING(member->GetName()))
            {
                id = member->GetName();
            }
        }
        else
#endif
        {
            id = ccx.GetMember()->GetName();
        }
        JSAutoByteString bytes;
        const char *name = JSID_IS_VOID(id) ? "Unknown" : bytes.encode(ccx, JSID_TO_STRING(id));
        if(!name)
        {
            name = "";
        }
        sz = JS_smprintf("%s [%s.%s]", *psz, iface->GetNameString(), name);
    }

    if(sz)
    {
        if(own)
            JS_smprintf_free(*psz);
        *psz = sz;
    }
}

void
XPCWrappedNativeScope::SetGlobal(XPCCallContext& ccx, JSObject* aGlobal,
                                 nsISupports* aNative)
{
    // We allow for calling this more than once. This feature is used by
    // nsXPConnect::InitClassesWithNewWrappedGlobal.

    mGlobalJSObject = aGlobal;
    mScriptObjectPrincipal = nsnull;

    // Try to find the native global object. If we didn't receive it explicitly,
    // we might be able to find it in the private slot.
    nsISupports* native = aNative;
    if (!native &&
        !(~js::GetObjectJSClass(aGlobal)->flags & (JSCLASS_HAS_PRIVATE |
                                                   JSCLASS_PRIVATE_IS_NSISUPPORTS)))
    {
        // Get the private. It might be a WN, in which case we dig deeper.
        native = (nsISupports*)xpc_GetJSPrivate(aGlobal);
        nsCOMPtr<nsIXPConnectWrappedNative> wn = do_QueryInterface(native);
        if (wn)
            native = static_cast<XPCWrappedNative*>(native)->GetIdentityObject();
    }

    // Now init our script object principal, if the new global has one.
    nsCOMPtr<nsIScriptObjectPrincipal> sop = do_QueryInterface(native);
    mScriptObjectPrincipal = sop;

    // Lookup 'globalObject.Object.prototype' for our wrapper's proto
    JSObject *objectPrototype =
        JS_GetObjectPrototype(ccx.GetJSContext(), aGlobal);
    if (objectPrototype)
        mPrototypeJSObject = objectPrototype;
    else
        NS_ERROR("Can't get globalObject.Object.prototype");

    // Clear the no helper wrapper prototype object so that a new one
    // gets created if needed.
    mPrototypeNoHelper = nsnull;
}

PRBool
XPCDispObject::WrapIDispatch(IDispatch *pDispatch, XPCCallContext &ccx,
                             JSObject *obj, jsval *rval)
{
    if(!pDispatch)
    {
        return PR_FALSE;
    }

    // Wrap the desired COM object
    nsCOMPtr<nsIXPConnectJSObjectHolder> holder;
    nsresult rv = ccx.GetXPConnect()->WrapNative(
        ccx, obj, reinterpret_cast<nsISupports*>(pDispatch), NSID_IDISPATCH,
        getter_AddRefs(holder));
    if(NS_FAILED(rv) || !holder)
    {
        return PR_FALSE;
    }
    JSObject * jsobj;
    if(NS_FAILED(holder->GetJSObject(&jsobj)))
        return PR_FALSE;
    *rval = OBJECT_TO_JSVAL(jsobj);
    return PR_TRUE;
}

// static
nsresult
nsXPCWrappedJS::GetNewOrUsed(XPCCallContext& ccx,
                             JSObject* aJSObj,
                             REFNSIID aIID,
                             nsISupports* aOuter,
                             nsXPCWrappedJS** wrapperResult)
{
    JSObject2WrappedJSMap* map;
    JSObject* rootJSObj;
    nsXPCWrappedJS* root = nsnull;
    nsXPCWrappedJS* wrapper = nsnull;
    nsXPCWrappedJSClass* clazz = nsnull;
    XPCJSRuntime* rt = ccx.GetRuntime();
    JSBool release_root = JS_FALSE;

    map = rt->GetWrappedJSMap();
    if (!map) {
        NS_ASSERTION(map,"bad map");
        return NS_ERROR_FAILURE;
    }

    nsXPCWrappedJSClass::GetNewOrUsed(ccx, aIID, &clazz);
    if (!clazz)
        return NS_ERROR_FAILURE;
    // from here on we need to return through 'return_wrapper'

    // always find the root JSObject
    rootJSObj = clazz->GetRootJSObject(ccx, aJSObj);
    if (!rootJSObj)
        goto return_wrapper;

    // look for the root wrapper, and if found, hold the map lock until
    // we've added our ref to prevent another thread from destroying it
    // under us
    {   // scoped lock
        XPCAutoLock lock(rt->GetMapLock());
        root = map->Find(rootJSObj);
        if (root) {
            if ((nsnull != (wrapper = root->Find(aIID))) ||
                (nsnull != (wrapper = root->FindInherited(aIID)))) {
                NS_ADDREF(wrapper);
                goto return_wrapper;
            }
        }
    }

    if (!root) {
        // build the root wrapper
        if (rootJSObj == aJSObj) {
            // the root will do double duty as the interface wrapper
            wrapper = root = new nsXPCWrappedJS(ccx, aJSObj, clazz, nsnull,
                                                aOuter);
            if (!root)
                goto return_wrapper;

            {   // scoped lock
#if DEBUG_xpc_leaks
                printf("Created nsXPCWrappedJS %p, JSObject is %p\n",
                       (void*)wrapper, (void*)aJSObj);
#endif
                XPCAutoLock lock(rt->GetMapLock());
                map->Add(root);
            }

            if (!CheckMainThreadOnly(root)) {
                XPCAutoLock lock(rt->GetMapLock());
                map->Remove(root);

                wrapper = NULL;
            }

            goto return_wrapper;
        } else {
            // just a root wrapper
            nsXPCWrappedJSClass* rootClazz = nsnull;
            nsXPCWrappedJSClass::GetNewOrUsed(ccx, NS_GET_IID(nsISupports),
                                              &rootClazz);
            if (!rootClazz)
                goto return_wrapper;

            root = new nsXPCWrappedJS(ccx, rootJSObj, rootClazz, nsnull, aOuter);
            NS_RELEASE(rootClazz);

            if (!root)
                goto return_wrapper;

            release_root = JS_TRUE;

            {   // scoped lock
#if DEBUG_xpc_leaks
                printf("Created nsXPCWrappedJS %p, JSObject is %p\n",
                       (void*)root, (void*)rootJSObj);
#endif
                XPCAutoLock lock(rt->GetMapLock());
                map->Add(root);
            }

            if (!CheckMainThreadOnly(root)) {
                XPCAutoLock lock(rt->GetMapLock());
//.........这里部分代码省略.........

JSBool
XPCNativeMember::Resolve(XPCCallContext& ccx, XPCNativeInterface* iface)
{
    if(IsConstant())
    {
        const nsXPTConstant* constant;
        if(NS_FAILED(iface->GetInterfaceInfo()->GetConstant(mIndex, &constant)))
            return JS_FALSE;

        const nsXPTCMiniVariant& mv = *constant->GetValue();

        // XXX Big Hack!
        nsXPTCVariant v;
        v.flags = 0;
        v.type = constant->GetType();
        memcpy(&v.val, &mv.val, sizeof(mv.val));

        jsval resultVal;

        if(!XPCConvert::NativeData2JS(ccx, &resultVal, &v.val, v.type,
                                      nsnull, nsnull, nsnull))
            return JS_FALSE;

        {   // scoped lock
            XPCAutoLock lock(ccx.GetRuntime()->GetMapLock());
            mVal = resultVal;
            mFlags |= RESOLVED;
        }

        return JS_TRUE;
    }
    // else...

    // This is a method or attribute - we'll be needing a function object

    intN argc;
    intN flags;
    JSNative callback;

    if(IsMethod())
    {
        const nsXPTMethodInfo* info;
        if(NS_FAILED(iface->GetInterfaceInfo()->GetMethodInfo(mIndex, &info)))
            return JS_FALSE;

        // Note: ASSUMES that retval is last arg.
        argc = (intN) info->GetParamCount();
        if(argc && info->GetParam((uint8)(argc-1)).IsRetval())
            argc-- ;

        flags = 0;
        callback = XPC_WN_CallMethod;
    }
    else
    {
        if(IsWritableAttribute())
            flags = JSFUN_GETTER | JSFUN_SETTER;
        else
            flags = JSFUN_GETTER;
        argc = 0;
        callback = XPC_WN_GetterSetter;
    }

    // We need to use the safe context for this thread because we don't want
    // to parent the new (and cached forever!) function object to the current
    // JSContext's global object. That would be bad!

    JSContext* cx = ccx.GetSafeJSContext();
    if(!cx)
        return JS_FALSE;

    const char *memberName = iface->GetMemberName(ccx, this);

    jsrefcount suspendDepth = 0;
    if(cx != ccx) {
        // Switching contexts, suspend the old and enter the new request.
        suspendDepth = JS_SuspendRequest(ccx);
        JS_BeginRequest(cx);
    }

    JSFunction *fun = JS_NewFunction(cx, callback, argc, flags, nsnull,
                                     memberName);

    if(suspendDepth) {
        JS_EndRequest(cx);
        JS_ResumeRequest(ccx, suspendDepth);
    }

    if(!fun)
        return JS_FALSE;

    JSObject* funobj = JS_GetFunctionObject(fun);
    if(!funobj)
        return JS_FALSE;

    AUTO_MARK_JSVAL(ccx, OBJECT_TO_JSVAL(funobj));

    STOBJ_CLEAR_PARENT(funobj);
    STOBJ_CLEAR_PROTO(funobj);

//.........这里部分代码省略.........

static bool
DefinePropertyIfFound(XPCCallContext& ccx,
                      HandleObject obj,
                      HandleId idArg,
                      XPCNativeSet* set,
                      XPCNativeInterface* ifaceArg,
                      XPCNativeMember* member,
                      XPCWrappedNativeScope* scope,
                      bool reflectToStringAndToSource,
                      XPCWrappedNative* wrapperToReflectInterfaceNames,
                      XPCWrappedNative* wrapperToReflectDoubleWrap,
                      XPCNativeScriptableInfo* scriptableInfo,
                      unsigned propFlags,
                      bool* resolved)
{
    RootedId id(ccx, idArg);
    RefPtr<XPCNativeInterface> iface = ifaceArg;
    XPCJSContext* xpccx = ccx.GetContext();
    bool found;
    const char* name;

    propFlags |= JSPROP_RESOLVING;

    if (set) {
        if (iface)
            found = true;
        else
            found = set->FindMember(id, &member, &iface);
    } else
        found = (nullptr != (member = iface->FindMember(id)));

    if (!found) {
        if (reflectToStringAndToSource) {
            JSNative call;
            uint32_t flags = 0;

            if (scriptableInfo) {
                nsCOMPtr<nsIClassInfo> classInfo = do_QueryInterface(
                    scriptableInfo->GetCallback());

                if (classInfo) {
                    nsresult rv = classInfo->GetFlags(&flags);
                    if (NS_FAILED(rv))
                        return Throw(rv, ccx);
                }
            }

            bool overwriteToString = !(flags & nsIClassInfo::DOM_OBJECT)
                || Preferences::GetBool("dom.XPCToStringForDOMClasses", false);

            if(id == xpccx->GetStringID(XPCJSContext::IDX_TO_STRING)
                && overwriteToString)
            {
                call = XPC_WN_Shared_ToString;
                name = xpccx->GetStringName(XPCJSContext::IDX_TO_STRING);
            } else if (id == xpccx->GetStringID(XPCJSContext::IDX_TO_SOURCE)) {
                call = XPC_WN_Shared_ToSource;
                name = xpccx->GetStringName(XPCJSContext::IDX_TO_SOURCE);
            } else if (id == SYMBOL_TO_JSID(
                               JS::GetWellKnownSymbol(ccx, JS::SymbolCode::toPrimitive)))
            {
                call = XPC_WN_Shared_toPrimitive;
                name = "[Symbol.toPrimitive]";
            } else {
                call = nullptr;
            }

            if (call) {
                RootedFunction fun(ccx, JS_NewFunction(ccx, call, 0, 0, name));
                if (!fun) {
                    JS_ReportOutOfMemory(ccx);
                    return false;
                }

                AutoResolveName arn(ccx, id);
                if (resolved)
                    *resolved = true;
                RootedObject value(ccx, JS_GetFunctionObject(fun));
                return JS_DefinePropertyById(ccx, obj, id, value,
                                             propFlags & ~JSPROP_ENUMERATE);
            }
        }
        // This *might* be a tearoff name that is not yet part of our
        // set. Let's lookup the name and see if it is the name of an
        // interface. Then we'll see if the object actually *does* this
        // interface and add a tearoff as necessary.

        if (wrapperToReflectInterfaceNames) {
            JSAutoByteString name;
            RefPtr<XPCNativeInterface> iface2;
            XPCWrappedNativeTearOff* to;
            RootedObject jso(ccx);
            nsresult rv = NS_OK;

            if (JSID_IS_STRING(id) &&
                name.encodeLatin1(ccx, JSID_TO_STRING(id)) &&
                (iface2 = XPCNativeInterface::GetNewOrUsed(name.ptr()), iface2) &&
                nullptr != (to = wrapperToReflectInterfaceNames->
                           FindTearOff(iface2, true, &rv)) &&
                nullptr != (jso = to->GetJSObject()))
//.........这里部分代码省略.........

JSBool XPCDispObject::Invoke(XPCCallContext & ccx, CallMode mode)
{
    nsresult rv = ccx.CanCallNow();
    if(NS_FAILED(rv))
    {
        // If the security manager is complaining then this is not really an
        // internal error in xpconnect. So, no reason to botch the assertion.
        NS_ASSERTION(rv == NS_ERROR_XPC_SECURITY_MANAGER_VETO, 
                     "hmm? CanCallNow failed in XPCDispObject::Invoke. "
                     "We are finding out about this late!");
        XPCThrower::Throw(rv, ccx);
        return JS_FALSE;
    }

    // TODO: Remove type cast and change GetIDispatchMember to use the correct type
    XPCDispInterface::Member* member = reinterpret_cast<XPCDispInterface::Member*>(ccx.GetIDispatchMember());
    XPCJSRuntime* rt = ccx.GetRuntime();
    XPCContext* xpcc = ccx.GetXPCContext();
    XPCPerThreadData* tls = ccx.GetThreadData();
    
    jsval* argv = ccx.GetArgv();
    uintN argc = ccx.GetArgc();

    tls->SetException(nsnull);
    xpcc->SetLastResult(NS_ERROR_UNEXPECTED);

    // set up the method index and do the security check if needed

    PRUint32 secFlag;
    PRUint32 secAction;

    switch(mode)
    {
        case CALL_METHOD:
            secFlag   = nsIXPCSecurityManager::HOOK_CALL_METHOD;
            secAction = nsIXPCSecurityManager::ACCESS_CALL_METHOD;
            break;
        case CALL_GETTER:
            secFlag   = nsIXPCSecurityManager::HOOK_GET_PROPERTY;
            secAction = nsIXPCSecurityManager::ACCESS_GET_PROPERTY;
            break;
        case CALL_SETTER:
            secFlag   = nsIXPCSecurityManager::HOOK_SET_PROPERTY;
            secAction = nsIXPCSecurityManager::ACCESS_SET_PROPERTY;
            break;
        default:
            NS_ASSERTION(0,"bad value");
            return JS_FALSE;
    }
    jsval name = member->GetName();

    nsIXPCSecurityManager* sm = xpcc->GetAppropriateSecurityManager(secFlag);
    XPCWrappedNative* wrapper = ccx.GetWrapper();
    if(sm && NS_FAILED(sm->CanAccess(secAction, &ccx, ccx,
                                     ccx.GetFlattenedJSObject(),
                                     wrapper->GetIdentityObject(),
                                     wrapper->GetClassInfo(), name,
                                     wrapper->GetSecurityInfoAddr())))
    {
        // the security manager vetoed. It should have set an exception.
        return JS_FALSE;
    }

    IDispatch * pObj = reinterpret_cast<IDispatch*>
                                       (ccx.GetTearOff()->GetNative());
    PRUint32 args = member->GetParamCount();
    uintN err;
    // Make sure setter has one argument
    if(mode == CALL_SETTER)
        args = 1;
    // Allow for optional parameters. We'll let COM handle the error if there
    // are not enough parameters
    if(argc < args)
        args = argc;
    XPCDispParams * params = new XPCDispParams(args);
    jsval val;
    // If this is a setter, we just need to convert the first parameter
    if(mode == CALL_SETTER)
    {
        params->SetNamedPropID();
        if(!XPCDispConvert::JSToCOM(ccx, argv[0], params->GetParamRef(0), err))
        {
            delete params;
            return ThrowBadParam(err, 0, ccx);
        }
    }
    else if(mode != CALL_GETTER)    // This is a function
    {
        // Convert the arguments to the function
        for(PRUint32 index = 0; index < args; ++index)
        {
            const XPCDispInterface::Member::ParamInfo & paramInfo = member->GetParamInfo(index);
            if(paramInfo.IsIn())
            {
                val = argv[index];
                if(paramInfo.IsOut())
                {
                    if(JSVAL_IS_PRIMITIVE(val) ||
                        !OBJ_GET_PROPERTY(ccx, JSVAL_TO_OBJECT(val),
                                          rt->GetStringID(XPCJSRuntime::IDX_VALUE),
//.........这里部分代码省略.........

//.........这里部分代码省略.........
                // NativeSets, and the WrappedNativeJSClasses...

                // Do the marking...
                XPCWrappedNativeScope::MarkAllWrappedNativesAndProtos();

                self->mDetachedWrappedNativeProtoMap->
                    Enumerate(DetachedWrappedNativeProtoMarker, nsnull);

                // Mark the sets used in the call contexts. There is a small
                // chance that a wrapper's set will change *while* a call is
                // happening which uses that wrapper's old interfface set. So,
                // we need to do this marking to avoid collecting those sets
                // that might no longer be otherwise reachable from the wrappers
                // or the wrapperprotos.

                // Skip this part if XPConnect is shutting down. We get into
                // bad locking problems with the thread iteration otherwise.
                if(!self->GetXPConnect()->IsShuttingDown())
                {
                    PRLock* threadLock = XPCPerThreadData::GetLock();
                    if(threadLock)
                    { // scoped lock
                        nsAutoLock lock(threadLock);

                        XPCPerThreadData* iterp = nsnull;
                        XPCPerThreadData* thread;

                        while(nsnull != (thread =
                                     XPCPerThreadData::IterateThreads(&iterp)))
                        {
                            // Mark those AutoMarkingPtr lists!
                            thread->MarkAutoRootsAfterJSFinalize();

                            XPCCallContext* ccxp = thread->GetCallContext();
                            while(ccxp)
                            {
                                // Deal with the strictness of callcontext that
                                // complains if you ask for a set when
                                // it is in a state where the set could not
                                // possibly be valid.
                                if(ccxp->CanGetSet())
                                {
                                    XPCNativeSet* set = ccxp->GetSet();
                                    if(set)
                                        set->Mark();
                                }
                                if(ccxp->CanGetInterface())
                                {
                                    XPCNativeInterface* iface = ccxp->GetInterface();
                                    if(iface)
                                        iface->Mark();
                                }
                                ccxp = ccxp->GetPrevCallContext();
                            }
                        }
                    }
                }

                // Do the sweeping...

                // We don't want to sweep the JSClasses at shutdown time.
                // At this point there may be JSObjects using them that have
                // been removed from the other maps.
                if(!self->GetXPConnect()->IsShuttingDown())
                {
                    self->mNativeScriptableSharedMap->

// static
JSBool XPCDispObject::Dispatch(XPCCallContext& ccx, IDispatch * disp,
                               DISPID dispID, CallMode mode, 
                               XPCDispParams * params,
                               jsval* retval,
                               XPCDispInterface::Member * member,
                               XPCJSRuntime* rt)
{
    _variant_t dispResult;
    jsval val;
    uintN err;
    uintN argc = params->GetParamCount();
    // Figure out what we're doing (getter/setter/method)
    WORD dispFlags;
    if(mode == CALL_SETTER)
    {
        dispFlags = DISPATCH_PROPERTYPUT;
    }
    else if(mode == CALL_GETTER)
    {
        dispFlags = DISPATCH_PROPERTYGET;
    }
    else
    {
        dispFlags = DISPATCH_METHOD;
    }
    HRESULT invokeResult;
    EXCEPINFO exception;
    // Scope the lock
    {
        // avoid deadlock in case the native method blocks somehow
        AutoJSSuspendRequest req(ccx);  // scoped suspend of request
        // call IDispatch's invoke
        invokeResult= disp->Invoke(
            dispID,                  // IDispatch ID
            IID_NULL,                // Reserved must be IID_NULL
            LOCALE_SYSTEM_DEFAULT,   // The locale context, use the system's
            dispFlags,               // Type of Invoke call
            params->GetDispParams(), // Parameters
            &dispResult,             // Where the result is stored
            &exception,              // Exception information
            0);                      // Index of an argument error
    }
    if(SUCCEEDED(invokeResult))
    {
        *retval = JSVAL_VOID;
        if(mode == CALL_METHOD)
        {
            NS_ASSERTION(member, "member must not be null if this is a method");
            for(PRUint32 index = 0; index < argc; ++index)
            {
                const XPCDispInterface::Member::ParamInfo & paramInfo = member->GetParamInfo(index);
                if(paramInfo.IsOut())
                {
                    if(!XPCDispConvert::COMToJS(ccx, params->GetParamRef(index), val, err))
                        return ThrowBadParam(err, index, ccx);

                    if(paramInfo.IsRetVal())
                    {
                        *retval = val;
                    }
                    else
                    {
                        jsval * argv = ccx.GetArgv();
                        // Out, in/out parameters must be objects
                        if(!JSVAL_IS_OBJECT(argv[index]) ||
                            !OBJ_SET_PROPERTY(ccx, JSVAL_TO_OBJECT(argv[index]),
                                rt->GetStringID(XPCJSRuntime::IDX_VALUE), &val))
                            return ThrowBadParam(NS_ERROR_XPC_CANT_SET_OUT_VAL, index, ccx);
                    }
                }
            }
        }
        if(dispResult.vt != VT_EMPTY)
        {
            if(!XPCDispConvert::COMToJS(ccx, dispResult, val, err))
            {
                ThrowBadParam(err, 0, ccx);
            }
            *retval = val;
        }
    }
    // Set the result and throw the error if one occured
    ccx.GetXPCContext()->SetLastResult(invokeResult);

    if(NS_FAILED(invokeResult))
    {
        XPCThrower::ThrowCOMError(ccx, invokeResult, NS_ERROR_XPC_COM_ERROR, 
                                  invokeResult == DISP_E_EXCEPTION ? 
                                      &exception : nsnull);
        return JS_FALSE;
    }
    return JS_TRUE;
}