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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
/* Manage the shared info about interfaces for use by wrappedNatives. */
#include "xpcprivate.h"
#include "XPCMaps.h"
#include "js/Wrapper.h"
#include "mozilla/MemoryReporting.h"
#include "mozilla/SourceLocation.h"
#include "nsIScriptError.h"
#include "nsPrintfCString.h"
#include "nsPointerHashKeys.h"
using namespace JS;
using namespace mozilla;
/***************************************************************************/
// XPCNativeMember
// static
bool XPCNativeMember::GetCallInfo(JSObject* funobj,
RefPtr<XPCNativeInterface>* pInterface,
XPCNativeMember** pMember) {
funobj = js::UncheckedUnwrap(funobj);
Value memberVal =
js::GetFunctionNativeReserved(funobj, XPC_FUNCTION_NATIVE_MEMBER_SLOT);
*pMember = static_cast<XPCNativeMember*>(memberVal.toPrivate());
*pInterface = (*pMember)->GetInterface();
return true;
}
bool XPCNativeMember::NewFunctionObject(XPCCallContext& ccx,
XPCNativeInterface* iface,
HandleObject parent, Value* pval) {
MOZ_ASSERT(!IsConstant(),
"Only call this if you're sure this is not a constant!");
return Resolve(ccx, iface, parent, pval);
}
bool XPCNativeMember::Resolve(XPCCallContext& ccx, XPCNativeInterface* iface,
HandleObject parent, Value* vp) {
MOZ_ASSERT(iface == GetInterface());
if (IsConstant()) {
RootedValue resultVal(ccx);
nsCString name;
if (NS_FAILED(iface->GetInterfaceInfo()->GetConstant(mIndex, &resultVal,
getter_Copies(name))))
return false;
*vp = resultVal;
return true;
}
// else...
// This is a method or attribute - we'll be needing a function object
int argc;
JSNative callback;
if (IsMethod()) {
const nsXPTMethodInfo* info;
if (NS_FAILED(iface->GetInterfaceInfo()->GetMethodInfo(mIndex, &info))) {
return false;
}
// Note: ASSUMES that retval is last arg.
argc = (int)info->ParamCount();
if (info->HasRetval()) {
argc--;
}
callback = XPC_WN_CallMethod;
} else {
argc = 0;
callback = XPC_WN_GetterSetter;
}
jsid name = GetName();
JS_MarkCrossZoneId(ccx, name);
JSFunction* fun;
if (name.isString()) {
fun = js::NewFunctionByIdWithReserved(ccx, callback, argc, 0, name);
} else {
fun = js::NewFunctionWithReserved(ccx, callback, argc, 0, nullptr);
}
if (!fun) {
return false;
}
JSObject* funobj = JS_GetFunctionObject(fun);
if (!funobj) {
return false;
}
js::SetFunctionNativeReserved(funobj, XPC_FUNCTION_NATIVE_MEMBER_SLOT,
PrivateValue(this));
js::SetFunctionNativeReserved(funobj, XPC_FUNCTION_PARENT_OBJECT_SLOT,
ObjectValue(*parent));
vp->setObject(*funobj);
return true;
}
/***************************************************************************/
// XPCNativeInterface
XPCNativeInterface::~XPCNativeInterface() {
XPCJSRuntime::Get()->GetIID2NativeInterfaceMap()->Remove(this);
}
// static
already_AddRefed<XPCNativeInterface> XPCNativeInterface::GetNewOrUsed(
JSContext* cx, const nsIID* iid) {
RefPtr<XPCNativeInterface> iface;
XPCJSRuntime* rt = XPCJSRuntime::Get();
IID2NativeInterfaceMap* map = rt->GetIID2NativeInterfaceMap();
if (!map) {
return nullptr;
}
iface = map->Find(*iid);
if (iface) {
return iface.forget();
}
const nsXPTInterfaceInfo* info = nsXPTInterfaceInfo::ByIID(*iid);
if (!info) {
return nullptr;
}
return NewInstance(cx, map, info);
}
// static
already_AddRefed<XPCNativeInterface> XPCNativeInterface::GetNewOrUsed(
JSContext* cx, const nsXPTInterfaceInfo* info) {
RefPtr<XPCNativeInterface> iface;
XPCJSRuntime* rt = XPCJSRuntime::Get();
IID2NativeInterfaceMap* map = rt->GetIID2NativeInterfaceMap();
if (!map) {
return nullptr;
}
iface = map->Find(info->IID());
if (iface) {
return iface.forget();
}
return NewInstance(cx, map, info);
}
// static
already_AddRefed<XPCNativeInterface> XPCNativeInterface::GetNewOrUsed(
JSContext* cx, const char* name) {
const nsXPTInterfaceInfo* info = nsXPTInterfaceInfo::ByName(name);
return info ? GetNewOrUsed(cx, info) : nullptr;
}
// static
already_AddRefed<XPCNativeInterface> XPCNativeInterface::GetISupports(
JSContext* cx) {
// XXX We should optimize this to cache this common XPCNativeInterface.
return GetNewOrUsed(cx, &NS_GET_IID(nsISupports));
}
// static
already_AddRefed<XPCNativeInterface> XPCNativeInterface::NewInstance(
JSContext* cx, IID2NativeInterfaceMap* aMap,
const nsXPTInterfaceInfo* aInfo) {
// XXX Investigate lazy init? This is a problem given the
// 'placement new' scheme - we need to at least know how big to make
// the object. We might do a scan of methods to determine needed size,
// then make our object, but avoid init'ing *any* members until asked?
// Find out how often we create these objects w/o really looking at
// (or using) the members.
if (aInfo->IsMainProcessScriptableOnly() && !XRE_IsParentProcess()) {
nsCOMPtr<nsIConsoleService> console(
do_GetService(NS_CONSOLESERVICE_CONTRACTID));
if (console) {
const char* intfNameChars = aInfo->Name();
nsPrintfCString errorMsg("Use of %s in content process is deprecated.",
intfNameChars);
auto location = JSCallingLocation::Get(cx);
nsCOMPtr<nsIScriptError> error(
do_CreateInstance(NS_SCRIPTERROR_CONTRACTID));
error->Init(NS_ConvertUTF8toUTF16(errorMsg), location.FileName(),
location.mLine, location.mColumn, nsIScriptError::warningFlag,
"chrome javascript"_ns, false /* from private window */,
true /* from chrome context */);
console->LogMessage(error);
}
}
// Make sure the code below does not GC. This means we don't need to trace the
// PropertyKeys in the MemberVector, or the XPCNativeInterface we create
// before it's added to the map.
JS::AutoCheckCannotGC nogc;
const uint16_t methodCount = aInfo->MethodCount();
const uint16_t constCount = aInfo->ConstantCount();
const uint16_t totalCount = methodCount + constCount;
using MemberVector =
mozilla::Vector<XPCNativeMember, 16, InfallibleAllocPolicy>;
MemberVector members;
MOZ_ALWAYS_TRUE(members.reserve(totalCount));
// NOTE: since getters and setters share a member, we might not use all
// of the member objects.
for (unsigned int i = 0; i < methodCount; i++) {
const nsXPTMethodInfo& info = aInfo->Method(i);
// don't reflect Addref or Release
if (i == 1 || i == 2) {
continue;
}
if (!info.IsReflectable()) {
continue;
}
jsid name;
if (!info.GetId(cx, name)) {
NS_ERROR("bad method name");
return nullptr;
}
if (info.IsSetter()) {
MOZ_ASSERT(!members.empty(), "bad setter");
// Note: ASSUMES Getter/Setter pairs are next to each other
// This is a rule of the typelib spec.
XPCNativeMember* cur = &members.back();
MOZ_ASSERT(cur->GetName() == name, "bad setter");
MOZ_ASSERT(cur->IsReadOnlyAttribute(), "bad setter");
MOZ_ASSERT(cur->GetIndex() == i - 1, "bad setter");
cur->SetWritableAttribute();
} else {
// XXX need better way to find dups
// MOZ_ASSERT(!LookupMemberByID(name),"duplicate method name");
size_t indexInInterface = members.length();
if (indexInInterface == XPCNativeMember::GetMaxIndexInInterface()) {
NS_WARNING("Too many members in interface");
return nullptr;
}
XPCNativeMember cur;
cur.SetName(name);
if (info.IsGetter()) {
cur.SetReadOnlyAttribute(i);
} else {
cur.SetMethod(i);
}
cur.SetIndexInInterface(indexInInterface);
members.infallibleAppend(cur);
}
}
for (unsigned int i = 0; i < constCount; i++) {
RootedValue constant(cx);
nsCString namestr;
if (NS_FAILED(aInfo->GetConstant(i, &constant, getter_Copies(namestr)))) {
return nullptr;
}
RootedString str(cx, JS_AtomizeString(cx, namestr.get()));
if (!str) {
NS_ERROR("bad constant name");
return nullptr;
}
jsid name = PropertyKey::NonIntAtom(str);
// XXX need better way to find dups
// MOZ_ASSERT(!LookupMemberByID(name),"duplicate method/constant name");
size_t indexInInterface = members.length();
if (indexInInterface == XPCNativeMember::GetMaxIndexInInterface()) {
NS_WARNING("Too many members in interface");
return nullptr;
}
XPCNativeMember cur;
cur.SetName(name);
cur.SetConstant(i);
cur.SetIndexInInterface(indexInInterface);
members.infallibleAppend(cur);
}
const char* bytes = aInfo->Name();
if (!bytes) {
return nullptr;
}
RootedString str(cx, JS_AtomizeString(cx, bytes));
if (!str) {
return nullptr;
}
RootedId interfaceName(cx, PropertyKey::NonIntAtom(str));
// Use placement new to create an object with the right amount of space
// to hold the members array
size_t size = sizeof(XPCNativeInterface);
if (members.length() > 1) {
size += (members.length() - 1) * sizeof(XPCNativeMember);
}
void* place = new char[size];
if (!place) {
return nullptr;
}
RefPtr<XPCNativeInterface> obj =
new (place) XPCNativeInterface(aInfo, interfaceName);
obj->mMemberCount = members.length();
// copy valid members
if (!members.empty()) {
memcpy(obj->mMembers, members.begin(),
members.length() * sizeof(XPCNativeMember));
}
if (!aMap->AddNew(obj)) {
NS_ERROR("failed to add our interface!");
return nullptr;
}
return obj.forget();
}
// static
void XPCNativeInterface::DestroyInstance(XPCNativeInterface* inst) {
inst->~XPCNativeInterface();
delete[] (char*)inst;
}
size_t XPCNativeInterface::SizeOfIncludingThis(MallocSizeOf mallocSizeOf) {
return mallocSizeOf(this);
}
void XPCNativeInterface::Trace(JSTracer* trc) {
JS::TraceRoot(trc, &mName, "XPCNativeInterface::mName");
for (size_t i = 0; i < mMemberCount; i++) {
JS::PropertyKey key = mMembers[i].GetName();
JS::TraceRoot(trc, &key, "XPCNativeInterface::mMembers");
MOZ_ASSERT(mMembers[i].GetName() == key);
}
}
void IID2NativeInterfaceMap::Trace(JSTracer* trc) {
for (Map::Enum e(mMap); !e.empty(); e.popFront()) {
XPCNativeInterface* iface = e.front().value();
iface->Trace(trc);
}
}
void XPCNativeInterface::DebugDump(int16_t depth) {
#ifdef DEBUG
XPC_LOG_ALWAYS(("XPCNativeInterface @ %p", this));
XPC_LOG_INDENT();
XPC_LOG_ALWAYS(("name is %s", GetNameString()));
XPC_LOG_ALWAYS(("mInfo @ %p", mInfo));
XPC_LOG_OUTDENT();
#endif
}
/***************************************************************************/
// XPCNativeSetKey
HashNumber XPCNativeSetKey::Hash() const {
HashNumber h = 0;
if (mBaseSet) {
// If we ever start using mCx here, adjust the constructors accordingly.
XPCNativeInterface** current = mBaseSet->GetInterfaceArray();
uint16_t count = mBaseSet->GetInterfaceCount();
for (uint16_t i = 0; i < count; i++) {
h = AddToHash(h, *(current++));
}
} else {
// A newly created set will contain nsISupports first...
RefPtr<XPCNativeInterface> isupp = XPCNativeInterface::GetISupports(mCx);
h = AddToHash(h, isupp.get());
// ...but no more than once.
if (isupp == mAddition) {
return h;
}
}
if (mAddition) {
h = AddToHash(h, mAddition.get());
}
return h;
}
/***************************************************************************/
// XPCNativeSet
XPCNativeSet::~XPCNativeSet() {
// Remove |this| before we clear the interfaces to ensure that the
// hashtable look up is correct.
XPCJSRuntime::Get()->GetNativeSetMap()->Remove(this);
for (int i = 0; i < mInterfaceCount; i++) {
NS_RELEASE(mInterfaces[i]);
}
}
// static
already_AddRefed<XPCNativeSet> XPCNativeSet::GetNewOrUsed(JSContext* cx,
const nsIID* iid) {
RefPtr<XPCNativeInterface> iface = XPCNativeInterface::GetNewOrUsed(cx, iid);
if (!iface) {
return nullptr;
}
XPCNativeSetKey key(cx, iface);
XPCJSRuntime* xpcrt = XPCJSRuntime::Get();
NativeSetMap* map = xpcrt->GetNativeSetMap();
if (!map) {
return nullptr;
}
RefPtr<XPCNativeSet> set = map->Find(&key);
if (set) {
return set.forget();
}
set = NewInstance(cx, {std::move(iface)});
if (!set) {
return nullptr;
}
if (!map->AddNew(&key, set)) {
NS_ERROR("failed to add our set!");
set = nullptr;
}
return set.forget();
}
// static
already_AddRefed<XPCNativeSet> XPCNativeSet::GetNewOrUsed(
JSContext* cx, nsIClassInfo* classInfo) {
XPCJSRuntime* xpcrt = XPCJSRuntime::Get();
ClassInfo2NativeSetMap* map = xpcrt->GetClassInfo2NativeSetMap();
if (!map) {
return nullptr;
}
RefPtr<XPCNativeSet> set = map->Find(classInfo);
if (set) {
return set.forget();
}
AutoTArray<nsIID, 4> iids;
if (NS_FAILED(classInfo->GetInterfaces(iids))) {
// Note: I'm making it OK for this call to fail so that one can add
// nsIClassInfo to classes implemented in script without requiring this
// method to be implemented.
// Make sure these are set correctly...
iids.Clear();
}
// Try to look up each IID's XPCNativeInterface object.
nsTArray<RefPtr<XPCNativeInterface>> interfaces(iids.Length());
for (auto& iid : iids) {
RefPtr<XPCNativeInterface> iface =
XPCNativeInterface::GetNewOrUsed(cx, &iid);
if (iface) {
interfaces.AppendElement(iface.forget());
}
}
// Build a set from the interfaces specified here.
if (interfaces.Length() > 0) {
set = NewInstance(cx, std::move(interfaces));
if (set) {
NativeSetMap* map2 = xpcrt->GetNativeSetMap();
if (!map2) {
return set.forget();
}
XPCNativeSetKey key(set);
XPCNativeSet* set2 = map2->Add(&key, set);
if (!set2) {
NS_ERROR("failed to add our set");
return nullptr;
}
// It is okay to find an existing entry here because
// we did not look for one before we called Add().
if (set2 != set) {
set = set2;
}
}
} else {
set = GetNewOrUsed(cx, &NS_GET_IID(nsISupports));
}
if (set) {
#ifdef DEBUG
XPCNativeSet* set2 =
#endif
map->Add(classInfo, set);
MOZ_ASSERT(set2, "failed to add our set!");
MOZ_ASSERT(set2 == set, "hashtables inconsistent!");
}
return set.forget();
}
// static
void XPCNativeSet::ClearCacheEntryForClassInfo(nsIClassInfo* classInfo) {
XPCJSRuntime* xpcrt = nsXPConnect::GetRuntimeInstance();
ClassInfo2NativeSetMap* map = xpcrt->GetClassInfo2NativeSetMap();
if (map) {
map->Remove(classInfo);
}
}
// static
already_AddRefed<XPCNativeSet> XPCNativeSet::GetNewOrUsed(
JSContext* cx, XPCNativeSetKey* key) {
NativeSetMap* map = XPCJSRuntime::Get()->GetNativeSetMap();
if (!map) {
return nullptr;
}
RefPtr<XPCNativeSet> set = map->Find(key);
if (set) {
return set.forget();
}
if (key->GetBaseSet()) {
set = NewInstanceMutate(key);
} else {
set = NewInstance(cx, {key->GetAddition()});
}
if (!set) {
return nullptr;
}
if (!map->AddNew(key, set)) {
NS_ERROR("failed to add our set!");
set = nullptr;
}
return set.forget();
}
// static
already_AddRefed<XPCNativeSet> XPCNativeSet::GetNewOrUsed(
JSContext* cx, XPCNativeSet* firstSet, XPCNativeSet* secondSet,
bool preserveFirstSetOrder) {
// Figure out how many interfaces we'll need in the new set.
uint32_t uniqueCount = firstSet->mInterfaceCount;
for (uint32_t i = 0; i < secondSet->mInterfaceCount; ++i) {
if (!firstSet->HasInterface(secondSet->mInterfaces[i])) {
uniqueCount++;
}
}
// If everything in secondSet was a duplicate, we can just use the first
// set.
if (uniqueCount == firstSet->mInterfaceCount) {
return RefPtr<XPCNativeSet>(firstSet).forget();
}
// If the secondSet is just a superset of the first, we can use it provided
// that the caller doesn't care about ordering.
if (!preserveFirstSetOrder && uniqueCount == secondSet->mInterfaceCount) {
return RefPtr<XPCNativeSet>(secondSet).forget();
}
// Ok, darn. Now we have to make a new set.
//
// It would be faster to just create the new set all at once, but that
// would involve wrangling with some pretty hairy code - especially since
// a lot of stuff assumes that sets are created by adding one interface to an
// existing set. So let's just do the slow and easy thing and hope that the
// above optimizations handle the common cases.
RefPtr<XPCNativeSet> currentSet = firstSet;
for (uint32_t i = 0; i < secondSet->mInterfaceCount; ++i) {
XPCNativeInterface* iface = secondSet->mInterfaces[i];
if (!currentSet->HasInterface(iface)) {
// Create a new augmented set, inserting this interface at the end.
XPCNativeSetKey key(currentSet, iface);
currentSet = XPCNativeSet::GetNewOrUsed(cx, &key);
if (!currentSet) {
return nullptr;
}
}
}
// We've got the union set. Hand it back to the caller.
MOZ_ASSERT(currentSet->mInterfaceCount == uniqueCount);
return currentSet.forget();
}
// static
already_AddRefed<XPCNativeSet> XPCNativeSet::NewInstance(
JSContext* cx, nsTArray<RefPtr<XPCNativeInterface>>&& array) {
if (array.Length() == 0) {
return nullptr;
}
// We impose the invariant:
// "All sets have exactly one nsISupports interface and it comes first."
// This is the place where we impose that rule - even if given inputs
// that don't exactly follow the rule.
RefPtr<XPCNativeInterface> isup = XPCNativeInterface::GetISupports(cx);
uint16_t slots = array.Length() + 1;
for (auto key = array.begin(); key != array.end(); key++) {
if (*key == isup) {
slots--;
}
}
// Use placement new to create an object with the right amount of space
// to hold the members array
int size = sizeof(XPCNativeSet);
if (slots > 1) {
size += (slots - 1) * sizeof(XPCNativeInterface*);
}
void* place = new char[size];
RefPtr<XPCNativeSet> obj = new (place) XPCNativeSet();
// Stick the nsISupports in front and skip additional nsISupport(s)
XPCNativeInterface** outp = (XPCNativeInterface**)&obj->mInterfaces;
NS_ADDREF(*(outp++) = isup);
for (auto key = array.begin(); key != array.end(); key++) {
RefPtr<XPCNativeInterface> cur = std::move(*key);
if (isup == cur) {
continue;
}
*(outp++) = cur.forget().take();
}
obj->mInterfaceCount = slots;
return obj.forget();
}
// static
already_AddRefed<XPCNativeSet> XPCNativeSet::NewInstanceMutate(
XPCNativeSetKey* key) {
XPCNativeSet* otherSet = key->GetBaseSet();
XPCNativeInterface* newInterface = key->GetAddition();
MOZ_ASSERT(otherSet);
if (!newInterface) {
return nullptr;
}
// Use placement new to create an object with the right amount of space
// to hold the members array
int size = sizeof(XPCNativeSet);
size += otherSet->mInterfaceCount * sizeof(XPCNativeInterface*);
void* place = new char[size];
RefPtr<XPCNativeSet> obj = new (place) XPCNativeSet();
obj->mInterfaceCount = otherSet->mInterfaceCount + 1;
XPCNativeInterface** src = otherSet->mInterfaces;
XPCNativeInterface** dest = obj->mInterfaces;
for (uint16_t i = 0; i < otherSet->mInterfaceCount; i++) {
NS_ADDREF(*dest++ = *src++);
}
NS_ADDREF(*dest++ = newInterface);
return obj.forget();
}
// static
void XPCNativeSet::DestroyInstance(XPCNativeSet* inst) {
inst->~XPCNativeSet();
delete[] (char*)inst;
}
size_t XPCNativeSet::SizeOfIncludingThis(MallocSizeOf mallocSizeOf) {
return mallocSizeOf(this);
}
void XPCNativeSet::DebugDump(int16_t depth) {
#ifdef DEBUG
depth--;
XPC_LOG_ALWAYS(("XPCNativeSet @ %p", this));
XPC_LOG_INDENT();
XPC_LOG_ALWAYS(("mInterfaceCount of %d", mInterfaceCount));
if (depth) {
for (uint16_t i = 0; i < mInterfaceCount; i++) {
mInterfaces[i]->DebugDump(depth);
}
}
XPC_LOG_OUTDENT();
#endif
}