michael@0: /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
michael@0: /* vim: set ts=8 sts=4 et sw=4 tw=99: */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "jsapi.h"
michael@0: #include "jsfriendapi.h"
michael@0: #include "jsprf.h"
michael@0: #include "nsCOMPtr.h"
michael@0: #include "AccessCheck.h"
michael@0: #include "WrapperFactory.h"
michael@0: #include "xpcprivate.h"
michael@0: #include "XPCInlines.h"
michael@0: #include "XPCQuickStubs.h"
michael@0: #include "mozilla/dom/BindingUtils.h"
michael@0: #include "mozilla/dom/Exceptions.h"
michael@0: 
michael@0: using namespace mozilla;
michael@0: using namespace JS;
michael@0: 
michael@0: extern const char* xpc_qsStringTable;
michael@0: 
michael@0: static const xpc_qsHashEntry *
michael@0: LookupEntry(uint32_t tableSize, const xpc_qsHashEntry *table, const nsID &iid)
michael@0: {
michael@0:     size_t i;
michael@0:     const xpc_qsHashEntry *p;
michael@0: 
michael@0:     i = iid.m0 % tableSize;
michael@0:     do
michael@0:     {
michael@0:         p = table + i;
michael@0:         if (p->iid.Equals(iid))
michael@0:             return p;
michael@0:         i = p->chain;
michael@0:     } while (i != XPC_QS_NULL_INDEX);
michael@0:     return nullptr;
michael@0: }
michael@0: 
michael@0: static const xpc_qsHashEntry *
michael@0: LookupInterfaceOrAncestor(uint32_t tableSize, const xpc_qsHashEntry *table,
michael@0:                           const nsID &iid)
michael@0: {
michael@0:     const xpc_qsHashEntry *entry = LookupEntry(tableSize, table, iid);
michael@0:     if (!entry) {
michael@0:         /*
michael@0:          * On a miss, we have to search for every interface the object
michael@0:          * supports, including ancestors.
michael@0:          */
michael@0:         nsCOMPtr<nsIInterfaceInfo> info;
michael@0:         if (NS_FAILED(nsXPConnect::XPConnect()->GetInfoForIID(&iid, getter_AddRefs(info))))
michael@0:             return nullptr;
michael@0: 
michael@0:         const nsIID *piid;
michael@0:         for (;;) {
michael@0:             nsCOMPtr<nsIInterfaceInfo> parent;
michael@0:             if (NS_FAILED(info->GetParent(getter_AddRefs(parent))) ||
michael@0:                 !parent ||
michael@0:                 NS_FAILED(parent->GetIIDShared(&piid))) {
michael@0:                 break;
michael@0:             }
michael@0:             entry = LookupEntry(tableSize, table, *piid);
michael@0:             if (entry)
michael@0:                 break;
michael@0:             info.swap(parent);
michael@0:         }
michael@0:     }
michael@0:     return entry;
michael@0: }
michael@0: 
michael@0: static MOZ_ALWAYS_INLINE bool
michael@0: HasBitInInterfacesBitmap(JSObject *obj, uint32_t interfaceBit)
michael@0: {
michael@0:     MOZ_ASSERT(IS_WN_REFLECTOR(obj), "Not a wrapper?");
michael@0: 
michael@0:     const XPCWrappedNativeJSClass *clasp =
michael@0:       (const XPCWrappedNativeJSClass*)js::GetObjectClass(obj);
michael@0:     return (clasp->interfacesBitmap & (1 << interfaceBit)) != 0;
michael@0: }
michael@0: 
michael@0: static void
michael@0: PointerFinalize(JSFreeOp *fop, JSObject *obj)
michael@0: {
michael@0:     JSPropertyOp *popp = static_cast<JSPropertyOp *>(JS_GetPrivate(obj));
michael@0:     delete popp;
michael@0: }
michael@0: 
michael@0: const JSClass
michael@0: PointerHolderClass = {
michael@0:     "Pointer", JSCLASS_HAS_PRIVATE,
michael@0:     JS_PropertyStub, JS_DeletePropertyStub, JS_PropertyStub, JS_StrictPropertyStub,
michael@0:     JS_EnumerateStub, JS_ResolveStub, JS_ConvertStub, PointerFinalize
michael@0: };
michael@0: 
michael@0: bool
michael@0: xpc_qsDefineQuickStubs(JSContext *cx, JSObject *protoArg, unsigned flags,
michael@0:                        uint32_t ifacec, const nsIID **interfaces,
michael@0:                        uint32_t tableSize, const xpc_qsHashEntry *table,
michael@0:                        const xpc_qsPropertySpec *propspecs,
michael@0:                        const xpc_qsFunctionSpec *funcspecs,
michael@0:                        const char *stringTable)
michael@0: {
michael@0:     /*
michael@0:      * Walk interfaces in reverse order to behave like XPConnect when a
michael@0:      * feature is defined in more than one of the interfaces.
michael@0:      *
michael@0:      * XPCNativeSet::FindMethod returns the first matching feature it finds,
michael@0:      * searching the interfaces forward.  Here, definitions toward the
michael@0:      * front of 'interfaces' overwrite those toward the back.
michael@0:      */
michael@0:     RootedObject proto(cx, protoArg);
michael@0:     for (uint32_t i = ifacec; i-- != 0;) {
michael@0:         const nsID &iid = *interfaces[i];
michael@0:         const xpc_qsHashEntry *entry =
michael@0:             LookupInterfaceOrAncestor(tableSize, table, iid);
michael@0: 
michael@0:         if (entry) {
michael@0:             for (;;) {
michael@0:                 // Define quick stubs for attributes.
michael@0:                 const xpc_qsPropertySpec *ps = propspecs + entry->prop_index;
michael@0:                 const xpc_qsPropertySpec *ps_end = ps + entry->n_props;
michael@0:                 for ( ; ps < ps_end; ++ps) {
michael@0:                     if (!JS_DefineProperty(cx, proto,
michael@0:                                            stringTable + ps->name_index,
michael@0:                                            JS::UndefinedHandleValue,
michael@0:                                            flags | JSPROP_SHARED | JSPROP_NATIVE_ACCESSORS,
michael@0:                                            (JSPropertyOp)ps->getter,
michael@0:                                            (JSStrictPropertyOp)ps->setter))
michael@0:                         return false;
michael@0:                 }
michael@0: 
michael@0:                 // Define quick stubs for methods.
michael@0:                 const xpc_qsFunctionSpec *fs = funcspecs + entry->func_index;
michael@0:                 const xpc_qsFunctionSpec *fs_end = fs + entry->n_funcs;
michael@0:                 for ( ; fs < fs_end; ++fs) {
michael@0:                     if (!JS_DefineFunction(cx, proto,
michael@0:                                            stringTable + fs->name_index,
michael@0:                                            reinterpret_cast<JSNative>(fs->native),
michael@0:                                            fs->arity, flags))
michael@0:                         return false;
michael@0:                 }
michael@0: 
michael@0:                 if (entry->newBindingProperties) {
michael@0:                     if (entry->newBindingProperties->regular) {
michael@0:                         mozilla::dom::DefineWebIDLBindingPropertiesOnXPCObject(cx, proto, entry->newBindingProperties->regular, false);
michael@0:                     }
michael@0:                     if (entry->newBindingProperties->chromeOnly &&
michael@0:                         xpc::AccessCheck::isChrome(js::GetContextCompartment(cx))) {
michael@0:                         mozilla::dom::DefineWebIDLBindingPropertiesOnXPCObject(cx, proto, entry->newBindingProperties->chromeOnly, false);
michael@0:                     }
michael@0:                 }
michael@0:                 // Next.
michael@0:                 size_t j = entry->parentInterface;
michael@0:                 if (j == XPC_QS_NULL_INDEX)
michael@0:                     break;
michael@0:                 entry = table + j;
michael@0:             }
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: bool
michael@0: xpc_qsThrow(JSContext *cx, nsresult rv)
michael@0: {
michael@0:     XPCThrower::Throw(rv, cx);
michael@0:     return false;
michael@0: }
michael@0: 
michael@0: /**
michael@0:  * Get the interface name and member name (for error messages).
michael@0:  *
michael@0:  * We could instead have each quick stub pass its name to the error-handling
michael@0:  * functions, as that name is statically known.  But that would be redundant;
michael@0:  * the information is handy at runtime anyway.  Also, this code often produces
michael@0:  * a more specific error message, e.g. "[nsIDOMHTMLDocument.appendChild]"
michael@0:  * rather than "[nsIDOMNode.appendChild]".
michael@0:  */
michael@0: static void
michael@0: GetMemberInfo(JSObject *obj, jsid memberId, const char **ifaceName)
michael@0: {
michael@0:     *ifaceName = "Unknown";
michael@0: 
michael@0:     // Don't try to generate a useful name if there are security wrappers,
michael@0:     // because it isn't worth the risk of something going wrong just to generate
michael@0:     // an error message. Instead, only handle the simple case where we have the
michael@0:     // reflector in hand.
michael@0:     if (IS_WN_REFLECTOR(obj)) {
michael@0:         XPCWrappedNative *wrapper = XPCWrappedNative::Get(obj);
michael@0:         XPCWrappedNativeProto *proto = wrapper->GetProto();
michael@0:         if (proto) {
michael@0:             XPCNativeSet *set = proto->GetSet();
michael@0:             if (set) {
michael@0:                 XPCNativeMember *member;
michael@0:                 XPCNativeInterface *iface;
michael@0: 
michael@0:                 if (set->FindMember(memberId, &member, &iface))
michael@0:                     *ifaceName = iface->GetNameString();
michael@0:             }
michael@0:         }
michael@0:     }
michael@0: }
michael@0: 
michael@0: static void
michael@0: GetMethodInfo(JSContext *cx, jsval *vp, const char **ifaceNamep, jsid *memberIdp)
michael@0: {
michael@0:     CallReceiver call = CallReceiverFromVp(vp);
michael@0:     RootedObject funobj(cx, &call.callee());
michael@0:     MOZ_ASSERT(JS_ObjectIsFunction(cx, funobj),
michael@0:                "JSNative callee should be Function object");
michael@0:     RootedString str(cx, JS_GetFunctionId(JS_GetObjectFunction(funobj)));
michael@0:     RootedId methodId(cx, str ? INTERNED_STRING_TO_JSID(cx, str) : JSID_VOID);
michael@0:     GetMemberInfo(&call.thisv().toObject(), methodId, ifaceNamep);
michael@0:     *memberIdp = methodId;
michael@0: }
michael@0: 
michael@0: static bool
michael@0: ThrowCallFailed(JSContext *cx, nsresult rv,
michael@0:                 const char *ifaceName, HandleId memberId, const char *memberName)
michael@0: {
michael@0:     /* Only one of memberId or memberName should be given. */
michael@0:     MOZ_ASSERT(JSID_IS_VOID(memberId) != !memberName);
michael@0: 
michael@0:     // From XPCThrower::ThrowBadResult.
michael@0:     char* sz;
michael@0:     const char* format;
michael@0:     const char* name;
michael@0: 
michael@0:     // If the cx already has a pending exception, just throw that.
michael@0:     //
michael@0:     // We used to check here to make sure the exception matched rv (whatever
michael@0:     // that means). But this meant that we'd be calling into JSAPI below with
michael@0:     // a pending exception, which isn't really kosher. The first exception thrown
michael@0:     // should generally take precedence anyway.
michael@0:     if (JS_IsExceptionPending(cx))
michael@0:         return false;
michael@0: 
michael@0:     // else...
michael@0: 
michael@0:     if (!nsXPCException::NameAndFormatForNSResult(NS_ERROR_XPC_NATIVE_RETURNED_FAILURE, nullptr, &format) ||
michael@0:         !format) {
michael@0:         format = "";
michael@0:     }
michael@0: 
michael@0:     JSAutoByteString memberNameBytes;
michael@0:     if (!memberName) {
michael@0:         memberName = JSID_IS_STRING(memberId)
michael@0:                      ? memberNameBytes.encodeLatin1(cx, JSID_TO_STRING(memberId))
michael@0:                      : "unknown";
michael@0:     }
michael@0:     if (nsXPCException::NameAndFormatForNSResult(rv, &name, nullptr)
michael@0:         && name) {
michael@0:         sz = JS_smprintf("%s 0x%x (%s) [%s.%s]",
michael@0:                          format, rv, name, ifaceName, memberName);
michael@0:     } else {
michael@0:         sz = JS_smprintf("%s 0x%x [%s.%s]",
michael@0:                          format, rv, ifaceName, memberName);
michael@0:     }
michael@0: 
michael@0:     dom::Throw(cx, rv, sz);
michael@0: 
michael@0:     if (sz)
michael@0:         JS_smprintf_free(sz);
michael@0: 
michael@0:     return false;
michael@0: }
michael@0: 
michael@0: bool
michael@0: xpc_qsThrowGetterSetterFailed(JSContext *cx, nsresult rv, JSObject *obj,
michael@0:                               jsid memberIdArg)
michael@0: {
michael@0:     RootedId memberId(cx, memberIdArg);
michael@0:     const char *ifaceName;
michael@0:     GetMemberInfo(obj, memberId, &ifaceName);
michael@0:     return ThrowCallFailed(cx, rv, ifaceName, memberId, nullptr);
michael@0: }
michael@0: 
michael@0: bool
michael@0: xpc_qsThrowGetterSetterFailed(JSContext *cx, nsresult rv, JSObject *objArg,
michael@0:                               const char* memberName)
michael@0: {
michael@0:     RootedObject obj(cx, objArg);
michael@0:     JSString *str = JS_InternString(cx, memberName);
michael@0:     if (!str) {
michael@0:         return false;
michael@0:     }
michael@0:     return xpc_qsThrowGetterSetterFailed(cx, rv, obj,
michael@0:                                          INTERNED_STRING_TO_JSID(cx, str));
michael@0: }
michael@0: 
michael@0: bool
michael@0: xpc_qsThrowGetterSetterFailed(JSContext *cx, nsresult rv, JSObject *obj,
michael@0:                               uint16_t memberIndex)
michael@0: {
michael@0:     return xpc_qsThrowGetterSetterFailed(cx, rv, obj,
michael@0:                                          xpc_qsStringTable + memberIndex);
michael@0: }
michael@0: 
michael@0: bool
michael@0: xpc_qsThrowMethodFailed(JSContext *cx, nsresult rv, jsval *vp)
michael@0: {
michael@0:     const char *ifaceName;
michael@0:     RootedId memberId(cx);
michael@0:     GetMethodInfo(cx, vp, &ifaceName, memberId.address());
michael@0:     return ThrowCallFailed(cx, rv, ifaceName, memberId, nullptr);
michael@0: }
michael@0: 
michael@0: static void
michael@0: ThrowBadArg(JSContext *cx, nsresult rv, const char *ifaceName,
michael@0:             jsid memberId, const char *memberName, unsigned paramnum)
michael@0: {
michael@0:     /* Only one memberId or memberName should be given. */
michael@0:     MOZ_ASSERT(JSID_IS_VOID(memberId) != !memberName);
michael@0: 
michael@0:     // From XPCThrower::ThrowBadParam.
michael@0:     char* sz;
michael@0:     const char* format;
michael@0: 
michael@0:     if (!nsXPCException::NameAndFormatForNSResult(rv, nullptr, &format))
michael@0:         format = "";
michael@0: 
michael@0:     JSAutoByteString memberNameBytes;
michael@0:     if (!memberName) {
michael@0:         memberName = JSID_IS_STRING(memberId)
michael@0:                      ? memberNameBytes.encodeLatin1(cx, JSID_TO_STRING(memberId))
michael@0:                      : "unknown";
michael@0:     }
michael@0:     sz = JS_smprintf("%s arg %u [%s.%s]",
michael@0:                      format, (unsigned int) paramnum, ifaceName, memberName);
michael@0: 
michael@0:     dom::Throw(cx, rv, sz);
michael@0: 
michael@0:     if (sz)
michael@0:         JS_smprintf_free(sz);
michael@0: }
michael@0: 
michael@0: void
michael@0: xpc_qsThrowBadArg(JSContext *cx, nsresult rv, jsval *vp, unsigned paramnum)
michael@0: {
michael@0:     const char *ifaceName;
michael@0:     RootedId memberId(cx);
michael@0:     GetMethodInfo(cx, vp, &ifaceName, memberId.address());
michael@0:     ThrowBadArg(cx, rv, ifaceName, memberId, nullptr, paramnum);
michael@0: }
michael@0: 
michael@0: void
michael@0: xpc_qsThrowBadArgWithCcx(XPCCallContext &ccx, nsresult rv, unsigned paramnum)
michael@0: {
michael@0:     XPCThrower::ThrowBadParam(rv, paramnum, ccx);
michael@0: }
michael@0: 
michael@0: void
michael@0: xpc_qsThrowBadArgWithDetails(JSContext *cx, nsresult rv, unsigned paramnum,
michael@0:                              const char *ifaceName, const char *memberName)
michael@0: {
michael@0:     ThrowBadArg(cx, rv, ifaceName, JSID_VOID, memberName, paramnum);
michael@0: }
michael@0: 
michael@0: void
michael@0: xpc_qsThrowBadSetterValue(JSContext *cx, nsresult rv,
michael@0:                           JSObject *obj, jsid propIdArg)
michael@0: {
michael@0:     RootedId propId(cx, propIdArg);
michael@0:     const char *ifaceName;
michael@0:     GetMemberInfo(obj, propId, &ifaceName);
michael@0:     ThrowBadArg(cx, rv, ifaceName, propId, nullptr, 0);
michael@0: }
michael@0: 
michael@0: void
michael@0: xpc_qsThrowBadSetterValue(JSContext *cx, nsresult rv,
michael@0:                           JSObject *objArg, const char* propName)
michael@0: {
michael@0:     RootedObject obj(cx, objArg);
michael@0:     JSString *str = JS_InternString(cx, propName);
michael@0:     if (!str) {
michael@0:         return;
michael@0:     }
michael@0:     xpc_qsThrowBadSetterValue(cx, rv, obj, INTERNED_STRING_TO_JSID(cx, str));
michael@0: }
michael@0: 
michael@0: void
michael@0: xpc_qsThrowBadSetterValue(JSContext *cx, nsresult rv, JSObject *obj,
michael@0:                           uint16_t name_index)
michael@0: {
michael@0:     xpc_qsThrowBadSetterValue(cx, rv, obj, xpc_qsStringTable + name_index);
michael@0: }
michael@0: 
michael@0: bool
michael@0: xpc_qsGetterOnlyPropertyStub(JSContext *cx, HandleObject obj, HandleId id, bool strict,
michael@0:                              MutableHandleValue vp)
michael@0: {
michael@0:     return JS_ReportErrorFlagsAndNumber(cx,
michael@0:                                         JSREPORT_WARNING | JSREPORT_STRICT |
michael@0:                                         JSREPORT_STRICT_MODE_ERROR,
michael@0:                                         js_GetErrorMessage, nullptr,
michael@0:                                         JSMSG_GETTER_ONLY);
michael@0: }
michael@0: 
michael@0: bool
michael@0: xpc_qsGetterOnlyNativeStub(JSContext *cx, unsigned argc, jsval *vp)
michael@0: {
michael@0:     return JS_ReportErrorFlagsAndNumber(cx,
michael@0:                                         JSREPORT_WARNING | JSREPORT_STRICT |
michael@0:                                         JSREPORT_STRICT_MODE_ERROR,
michael@0:                                         js_GetErrorMessage, nullptr,
michael@0:                                         JSMSG_GETTER_ONLY);
michael@0: }
michael@0: 
michael@0: xpc_qsDOMString::xpc_qsDOMString(JSContext *cx, HandleValue v,
michael@0:                                  MutableHandleValue pval, bool notpassed,
michael@0:                                  StringificationBehavior nullBehavior,
michael@0:                                  StringificationBehavior undefinedBehavior)
michael@0: {
michael@0:     typedef implementation_type::char_traits traits;
michael@0:     // From the T_DOMSTRING case in XPCConvert::JSData2Native.
michael@0:     JSString *s = InitOrStringify<traits>(cx, v,
michael@0:                                           pval, notpassed,
michael@0:                                           nullBehavior,
michael@0:                                           undefinedBehavior);
michael@0:     if (!s)
michael@0:         return;
michael@0: 
michael@0:     size_t len;
michael@0:     const jschar *chars = JS_GetStringCharsZAndLength(cx, s, &len);
michael@0:     if (!chars) {
michael@0:         mValid = false;
michael@0:         return;
michael@0:     }
michael@0: 
michael@0:     new(mBuf) implementation_type(chars, len);
michael@0:     mValid = true;
michael@0: }
michael@0: 
michael@0: xpc_qsACString::xpc_qsACString(JSContext *cx, HandleValue v,
michael@0:                                MutableHandleValue pval, bool notpassed,
michael@0:                                StringificationBehavior nullBehavior,
michael@0:                                StringificationBehavior undefinedBehavior)
michael@0: {
michael@0:     typedef implementation_type::char_traits traits;
michael@0:     // From the T_CSTRING case in XPCConvert::JSData2Native.
michael@0:     JSString *s = InitOrStringify<traits>(cx, v,
michael@0:                                           pval, notpassed,
michael@0:                                           nullBehavior,
michael@0:                                           undefinedBehavior);
michael@0:     if (!s)
michael@0:         return;
michael@0: 
michael@0:     size_t len = JS_GetStringEncodingLength(cx, s);
michael@0:     if (len == size_t(-1)) {
michael@0:         mValid = false;
michael@0:         return;
michael@0:     }
michael@0: 
michael@0:     JSAutoByteString bytes(cx, s);
michael@0:     if (!bytes) {
michael@0:         mValid = false;
michael@0:         return;
michael@0:     }
michael@0: 
michael@0:     new(mBuf) implementation_type(bytes.ptr(), len);
michael@0:     mValid = true;
michael@0: }
michael@0: 
michael@0: xpc_qsAUTF8String::xpc_qsAUTF8String(JSContext *cx, HandleValue v, MutableHandleValue pval, bool notpassed)
michael@0: {
michael@0:     typedef nsCharTraits<char16_t> traits;
michael@0:     // From the T_UTF8STRING  case in XPCConvert::JSData2Native.
michael@0:     JSString *s = InitOrStringify<traits>(cx, v, pval, notpassed, eNull, eNull);
michael@0:     if (!s)
michael@0:         return;
michael@0: 
michael@0:     size_t len;
michael@0:     const char16_t *chars = JS_GetStringCharsZAndLength(cx, s, &len);
michael@0:     if (!chars) {
michael@0:         mValid = false;
michael@0:         return;
michael@0:     }
michael@0: 
michael@0:     new(mBuf) implementation_type(chars, len);
michael@0:     mValid = true;
michael@0: }
michael@0: 
michael@0: static nsresult
michael@0: getNative(nsISupports *idobj,
michael@0:           HandleObject obj,
michael@0:           const nsIID &iid,
michael@0:           void **ppThis,
michael@0:           nsISupports **pThisRef,
michael@0:           jsval *vp)
michael@0: {
michael@0:     nsresult rv = idobj->QueryInterface(iid, ppThis);
michael@0:     *pThisRef = static_cast<nsISupports*>(*ppThis);
michael@0:     if (NS_SUCCEEDED(rv))
michael@0:         *vp = OBJECT_TO_JSVAL(obj);
michael@0:     return rv;
michael@0: }
michael@0: 
michael@0: static inline nsresult
michael@0: getNativeFromWrapper(JSContext *cx,
michael@0:                      XPCWrappedNative *wrapper,
michael@0:                      const nsIID &iid,
michael@0:                      void **ppThis,
michael@0:                      nsISupports **pThisRef,
michael@0:                      jsval *vp)
michael@0: {
michael@0:     RootedObject obj(cx, wrapper->GetFlatJSObject());
michael@0:     return getNative(wrapper->GetIdentityObject(), obj, iid, ppThis, pThisRef,
michael@0:                      vp);
michael@0: }
michael@0: 
michael@0: 
michael@0: nsresult
michael@0: getWrapper(JSContext *cx,
michael@0:            JSObject *obj,
michael@0:            XPCWrappedNative **wrapper,
michael@0:            JSObject **cur,
michael@0:            XPCWrappedNativeTearOff **tearoff)
michael@0: {
michael@0:     // We can have at most three layers in need of unwrapping here:
michael@0:     // * A (possible) security wrapper
michael@0:     // * A (possible) Xray waiver
michael@0:     // * A (possible) outer window
michael@0:     //
michael@0:     // If we pass stopAtOuter == false, we can handle all three with one call
michael@0:     // to js::CheckedUnwrap.
michael@0:     if (js::IsWrapper(obj)) {
michael@0:         JSObject* inner = js::CheckedUnwrap(obj, /* stopAtOuter = */ false);
michael@0: 
michael@0:         // Hack - For historical reasons, wrapped chrome JS objects have been
michael@0:         // passable as native interfaces. We'd like to fix this, but it
michael@0:         // involves fixing the contacts API and PeerConnection to stop using
michael@0:         // COWs. This needs to happen, but for now just preserve the old
michael@0:         // behavior.
michael@0:         //
michael@0:         // Note that there is an identical hack in
michael@0:         // XPCConvert::JSObject2NativeInterface which should be removed if this
michael@0:         // one is.
michael@0:         if (!inner && MOZ_UNLIKELY(xpc::WrapperFactory::IsCOW(obj)))
michael@0:             inner = js::UncheckedUnwrap(obj);
michael@0: 
michael@0:         // The safe unwrap might have failed if we encountered an object that
michael@0:         // we're not allowed to unwrap. If it didn't fail though, we should be
michael@0:         // done with wrappers.
michael@0:         if (!inner)
michael@0:             return NS_ERROR_XPC_SECURITY_MANAGER_VETO;
michael@0:         MOZ_ASSERT(!js::IsWrapper(inner));
michael@0: 
michael@0:         obj = inner;
michael@0:     }
michael@0: 
michael@0:     // Start with sane values.
michael@0:     *wrapper = nullptr;
michael@0:     *cur = nullptr;
michael@0:     *tearoff = nullptr;
michael@0: 
michael@0:     if (dom::IsDOMObject(obj)) {
michael@0:         *cur = obj;
michael@0: 
michael@0:         return NS_OK;
michael@0:     }
michael@0: 
michael@0:     // Handle tearoffs.
michael@0:     //
michael@0:     // If |obj| is of the tearoff class, that means we're dealing with a JS
michael@0:     // object reflection of a particular interface (ie, |foo.nsIBar|). These
michael@0:     // JS objects are parented to their wrapper, so we snag the tearoff object
michael@0:     // along the way (if desired), and then set |obj| to its parent.
michael@0:     const js::Class* clasp = js::GetObjectClass(obj);
michael@0:     if (clasp == &XPC_WN_Tearoff_JSClass) {
michael@0:         *tearoff = (XPCWrappedNativeTearOff*) js::GetObjectPrivate(obj);
michael@0:         obj = js::GetObjectParent(obj);
michael@0:     }
michael@0: 
michael@0:     // If we've got a WN, store things the way callers expect. Otherwise, leave
michael@0:     // things null and return.
michael@0:     if (IS_WN_CLASS(clasp))
michael@0:         *wrapper = XPCWrappedNative::Get(obj);
michael@0: 
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: nsresult
michael@0: castNative(JSContext *cx,
michael@0:            XPCWrappedNative *wrapper,
michael@0:            JSObject *curArg,
michael@0:            XPCWrappedNativeTearOff *tearoff,
michael@0:            const nsIID &iid,
michael@0:            void **ppThis,
michael@0:            nsISupports **pThisRef,
michael@0:            MutableHandleValue vp)
michael@0: {
michael@0:     RootedObject cur(cx, curArg);
michael@0:     if (wrapper) {
michael@0:         nsresult rv = getNativeFromWrapper(cx,wrapper, iid, ppThis, pThisRef,
michael@0:                                            vp.address());
michael@0: 
michael@0:         if (rv != NS_ERROR_NO_INTERFACE)
michael@0:             return rv;
michael@0:     } else if (cur) {
michael@0:         nsISupports *native;
michael@0:         if (!(native = mozilla::dom::UnwrapDOMObjectToISupports(cur))) {
michael@0:             *pThisRef = nullptr;
michael@0:             return NS_ERROR_ILLEGAL_VALUE;
michael@0:         }
michael@0: 
michael@0:         if (NS_SUCCEEDED(getNative(native, cur, iid, ppThis, pThisRef, vp.address()))) {
michael@0:             return NS_OK;
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     *pThisRef = nullptr;
michael@0:     return NS_ERROR_XPC_BAD_OP_ON_WN_PROTO;
michael@0: }
michael@0: 
michael@0: nsISupports*
michael@0: castNativeFromWrapper(JSContext *cx,
michael@0:                       JSObject *obj,
michael@0:                       uint32_t interfaceBit,
michael@0:                       uint32_t protoID,
michael@0:                       int32_t protoDepth,
michael@0:                       nsISupports **pRef,
michael@0:                       MutableHandleValue pVal,
michael@0:                       nsresult *rv)
michael@0: {
michael@0:     XPCWrappedNative *wrapper;
michael@0:     XPCWrappedNativeTearOff *tearoff;
michael@0:     JSObject *cur;
michael@0: 
michael@0:     if (IS_WN_REFLECTOR(obj)) {
michael@0:         cur = obj;
michael@0:         wrapper = XPCWrappedNative::Get(obj);
michael@0:         tearoff = nullptr;
michael@0:     } else {
michael@0:         *rv = getWrapper(cx, obj, &wrapper, &cur, &tearoff);
michael@0:         if (NS_FAILED(*rv))
michael@0:             return nullptr;
michael@0:     }
michael@0: 
michael@0:     nsISupports *native;
michael@0:     if (wrapper) {
michael@0:         native = wrapper->GetIdentityObject();
michael@0:         cur = wrapper->GetFlatJSObject();
michael@0:         if (!native || !HasBitInInterfacesBitmap(cur, interfaceBit)) {
michael@0:             native = nullptr;
michael@0:         }
michael@0:     } else if (cur && protoDepth >= 0) {
michael@0:         const mozilla::dom::DOMClass* domClass =
michael@0:             mozilla::dom::GetDOMClass(cur);
michael@0:         native = mozilla::dom::UnwrapDOMObject<nsISupports>(cur);
michael@0:         if (native &&
michael@0:             (uint32_t)domClass->mInterfaceChain[protoDepth] != protoID) {
michael@0:             native = nullptr;
michael@0:         }
michael@0:     } else {
michael@0:         native = nullptr;
michael@0:     }
michael@0: 
michael@0:     if (native) {
michael@0:         *pRef = nullptr;
michael@0:         pVal.setObjectOrNull(cur);
michael@0:         *rv = NS_OK;
michael@0:     } else {
michael@0:         *rv = NS_ERROR_XPC_BAD_CONVERT_JS;
michael@0:     }
michael@0: 
michael@0:     return native;
michael@0: }
michael@0: 
michael@0: bool
michael@0: xpc_qsUnwrapThisFromCcxImpl(XPCCallContext &ccx,
michael@0:                             const nsIID &iid,
michael@0:                             void **ppThis,
michael@0:                             nsISupports **pThisRef,
michael@0:                             jsval *vp)
michael@0: {
michael@0:     nsISupports *native = ccx.GetIdentityObject();
michael@0:     if (!native)
michael@0:         return xpc_qsThrow(ccx.GetJSContext(), NS_ERROR_XPC_HAS_BEEN_SHUTDOWN);
michael@0: 
michael@0:     RootedObject obj(ccx, ccx.GetFlattenedJSObject());
michael@0:     nsresult rv = getNative(native, obj, iid, ppThis, pThisRef, vp);
michael@0:     if (NS_FAILED(rv))
michael@0:         return xpc_qsThrow(ccx.GetJSContext(), rv);
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: nsresult
michael@0: xpc_qsUnwrapArgImpl(JSContext *cx,
michael@0:                     HandleValue v,
michael@0:                     const nsIID &iid,
michael@0:                     void **ppArg,
michael@0:                     nsISupports **ppArgRef,
michael@0:                     MutableHandleValue vp)
michael@0: {
michael@0:     nsresult rv;
michael@0:     RootedObject src(cx, xpc_qsUnwrapObj(v, ppArgRef, &rv));
michael@0:     if (!src) {
michael@0:         *ppArg = nullptr;
michael@0: 
michael@0:         return rv;
michael@0:     }
michael@0: 
michael@0:     XPCWrappedNative *wrapper;
michael@0:     XPCWrappedNativeTearOff *tearoff;
michael@0:     JSObject *obj2;
michael@0:     rv = getWrapper(cx, src, &wrapper, &obj2, &tearoff);
michael@0:     NS_ENSURE_SUCCESS(rv, rv);
michael@0: 
michael@0:     if (wrapper || obj2) {
michael@0:         if (NS_FAILED(castNative(cx, wrapper, obj2, tearoff, iid, ppArg,
michael@0:                                  ppArgRef, vp)))
michael@0:             return NS_ERROR_XPC_BAD_CONVERT_JS;
michael@0:         return NS_OK;
michael@0:     }
michael@0:     // else...
michael@0:     // Slow path.
michael@0: 
michael@0:     // Try to unwrap a slim wrapper.
michael@0:     nsISupports *iface;
michael@0:     if (XPCConvert::GetISupportsFromJSObject(src, &iface)) {
michael@0:         if (!iface || NS_FAILED(iface->QueryInterface(iid, ppArg))) {
michael@0:             *ppArgRef = nullptr;
michael@0:             return NS_ERROR_XPC_BAD_CONVERT_JS;
michael@0:         }
michael@0: 
michael@0:         *ppArgRef = static_cast<nsISupports*>(*ppArg);
michael@0:         return NS_OK;
michael@0:     }
michael@0: 
michael@0:     // Create the ccx needed for quick stubs.
michael@0:     XPCCallContext ccx(JS_CALLER, cx);
michael@0:     if (!ccx.IsValid()) {
michael@0:         *ppArgRef = nullptr;
michael@0:         return NS_ERROR_XPC_BAD_CONVERT_JS;
michael@0:     }
michael@0: 
michael@0:     nsRefPtr<nsXPCWrappedJS> wrappedJS;
michael@0:     rv = nsXPCWrappedJS::GetNewOrUsed(src, iid, getter_AddRefs(wrappedJS));
michael@0:     if (NS_FAILED(rv) || !wrappedJS) {
michael@0:         *ppArgRef = nullptr;
michael@0:         return rv;
michael@0:     }
michael@0: 
michael@0:     // We need to go through the QueryInterface logic to make this return
michael@0:     // the right thing for the various 'special' interfaces; e.g.
michael@0:     // nsIPropertyBag. We must use AggregatedQueryInterface in cases where
michael@0:     // there is an outer to avoid nasty recursion.
michael@0:     rv = wrappedJS->QueryInterface(iid, ppArg);
michael@0:     if (NS_SUCCEEDED(rv)) {
michael@0:         *ppArgRef = static_cast<nsISupports*>(*ppArg);
michael@0:         vp.setObjectOrNull(wrappedJS->GetJSObject());
michael@0:     }
michael@0:     return rv;
michael@0: }
michael@0: 
michael@0: bool
michael@0: xpc_qsJsvalToCharStr(JSContext *cx, HandleValue v, JSAutoByteString *bytes)
michael@0: {
michael@0:     MOZ_ASSERT(!bytes->ptr());
michael@0: 
michael@0:     if (v.isNullOrUndefined())
michael@0:       return true;
michael@0: 
michael@0:     JSString *str = ToString(cx, v);
michael@0:     if (!str)
michael@0:       return false;
michael@0:     return !!bytes->encodeLatin1(cx, str);
michael@0: }
michael@0: 
michael@0: namespace xpc {
michael@0: 
michael@0: bool
michael@0: NonVoidStringToJsval(JSContext *cx, nsAString &str, MutableHandleValue rval)
michael@0: {
michael@0:     nsStringBuffer* sharedBuffer;
michael@0:     if (!XPCStringConvert::ReadableToJSVal(cx, str, &sharedBuffer, rval))
michael@0:       return false;
michael@0: 
michael@0:     if (sharedBuffer) {
michael@0:         // The string was shared but ReadableToJSVal didn't addref it.
michael@0:         // Move the ownership from str to jsstr.
michael@0:         str.ForgetSharedBuffer();
michael@0:     }
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: } // namespace xpc
michael@0: 
michael@0: bool
michael@0: xpc_qsXPCOMObjectToJsval(JSContext *cx, qsObjectHelper &aHelper,
michael@0:                          const nsIID *iid, XPCNativeInterface **iface,
michael@0:                          MutableHandleValue rval)
michael@0: {
michael@0:     NS_PRECONDITION(iface, "Who did that and why?");
michael@0: 
michael@0:     // From the T_INTERFACE case in XPCConvert::NativeData2JS.
michael@0:     // This is one of the slowest things quick stubs do.
michael@0: 
michael@0:     nsresult rv;
michael@0:     if (!XPCConvert::NativeInterface2JSObject(rval, nullptr,
michael@0:                                               aHelper, iid, iface,
michael@0:                                               true, &rv)) {
michael@0:         // I can't tell if NativeInterface2JSObject throws JS exceptions
michael@0:         // or not.  This is a sloppy stab at the right semantics; the
michael@0:         // method really ought to be fixed to behave consistently.
michael@0:         if (!JS_IsExceptionPending(cx))
michael@0:             xpc_qsThrow(cx, NS_FAILED(rv) ? rv : NS_ERROR_UNEXPECTED);
michael@0:         return false;
michael@0:     }
michael@0: 
michael@0: #ifdef DEBUG
michael@0:     JSObject* jsobj = rval.toObjectOrNull();
michael@0:     if (jsobj && !js::GetObjectParent(jsobj))
michael@0:         MOZ_ASSERT(js::GetObjectClass(jsobj)->flags & JSCLASS_IS_GLOBAL,
michael@0:                    "Why did we recreate this wrapper?");
michael@0: #endif
michael@0: 
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: bool
michael@0: xpc_qsVariantToJsval(JSContext *aCx,
michael@0:                      nsIVariant *p,
michael@0:                      MutableHandleValue rval)
michael@0: {
michael@0:     // From the T_INTERFACE case in XPCConvert::NativeData2JS.
michael@0:     // Error handling is in XPCWrappedNative::CallMethod.
michael@0:     if (p) {
michael@0:         nsresult rv;
michael@0:         bool ok = XPCVariant::VariantDataToJS(p, &rv, rval);
michael@0:         if (!ok)
michael@0:             xpc_qsThrow(aCx, rv);
michael@0:         return ok;
michael@0:     }
michael@0:     rval.setNull();
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: #ifdef DEBUG
michael@0: void
michael@0: xpc_qsAssertContextOK(JSContext *cx)
michael@0: {
michael@0:     XPCJSContextStack* stack = XPCJSRuntime::Get()->GetJSContextStack();
michael@0: 
michael@0:     JSContext *topJSContext = stack->Peek();
michael@0: 
michael@0:     // This is what we're actually trying to assert here.
michael@0:     MOZ_ASSERT(cx == topJSContext, "wrong context on XPCJSContextStack!");
michael@0: }
michael@0: #endif