https://github.com/mozilla/gecko-dev
Tip revision: fe30cec62a8deb9f030011cb6cbe8bb4e61f7758 authored by ffxbld on 06 August 2015, 07:14:32 UTC
Added FIREFOX_38_1_1esr_RELEASE FIREFOX_38_1_1esr_BUILD2 tag(s) for changeset 63989e580394. DONTBUILD CLOSED TREE a=release
Added FIREFOX_38_1_1esr_RELEASE FIREFOX_38_1_1esr_BUILD2 tag(s) for changeset 63989e580394. DONTBUILD CLOSED TREE a=release
Tip revision: fe30cec
nsJSEnvironment.cpp
/* -*- 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
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "nsError.h"
#include "nsJSEnvironment.h"
#include "nsIScriptGlobalObject.h"
#include "nsIScriptObjectPrincipal.h"
#include "nsIDOMChromeWindow.h"
#include "nsPIDOMWindow.h"
#include "nsIScriptSecurityManager.h"
#include "nsDOMCID.h"
#include "nsIServiceManager.h"
#include "nsIXPConnect.h"
#include "nsIJSRuntimeService.h"
#include "nsCOMPtr.h"
#include "nsISupportsPrimitives.h"
#include "nsReadableUtils.h"
#include "nsDOMJSUtils.h"
#include "nsJSUtils.h"
#include "nsIDocShell.h"
#include "nsIDocShellTreeItem.h"
#include "nsPresContext.h"
#include "nsIConsoleService.h"
#include "nsIScriptError.h"
#include "nsIInterfaceRequestor.h"
#include "nsIInterfaceRequestorUtils.h"
#include "nsIPrompt.h"
#include "nsIObserverService.h"
#include "nsITimer.h"
#include "nsIAtom.h"
#include "nsContentUtils.h"
#include "mozilla/EventDispatcher.h"
#include "nsIContent.h"
#include "nsCycleCollector.h"
#include "nsNetUtil.h"
#include "nsXPCOMCIDInternal.h"
#include "nsIXULRuntime.h"
#include "nsTextFormatter.h"
#include "ScriptSettings.h"
#include "xpcpublic.h"
#include "jsapi.h"
#include "jswrapper.h"
#include "js/SliceBudget.h"
#include "nsIArray.h"
#include "nsIObjectInputStream.h"
#include "nsIObjectOutputStream.h"
#include "prmem.h"
#include "WrapperFactory.h"
#include "nsGlobalWindow.h"
#include "nsScriptNameSpaceManager.h"
#include "StructuredCloneTags.h"
#include "mozilla/AutoRestore.h"
#include "mozilla/dom/CryptoKey.h"
#include "mozilla/dom/ErrorEvent.h"
#include "mozilla/dom/ImageDataBinding.h"
#include "mozilla/dom/ImageData.h"
#include "mozilla/dom/StructuredClone.h"
#include "mozilla/dom/SubtleCryptoBinding.h"
#include "mozilla/ipc/BackgroundUtils.h"
#include "mozilla/ipc/PBackgroundSharedTypes.h"
#include "nsAXPCNativeCallContext.h"
#include "mozilla/CycleCollectedJSRuntime.h"
#include "nsJSPrincipals.h"
#ifdef XP_MACOSX
// AssertMacros.h defines 'check' and conflicts with AccessCheck.h
#undef check
#endif
#include "AccessCheck.h"
#include "prlog.h"
#include "prthread.h"
#include "mozilla/Preferences.h"
#include "mozilla/Telemetry.h"
#include "mozilla/dom/BindingUtils.h"
#include "mozilla/Attributes.h"
#include "mozilla/dom/asmjscache/AsmJSCache.h"
#include "mozilla/dom/CanvasRenderingContext2DBinding.h"
#include "mozilla/CycleCollectedJSRuntime.h"
#include "mozilla/ContentEvents.h"
#include "nsCycleCollectionNoteRootCallback.h"
#include "GeckoProfiler.h"
using namespace mozilla;
using namespace mozilla::dom;
const size_t gStackSize = 8192;
// Thank you Microsoft!
#ifdef CompareString
#undef CompareString
#endif
#define NS_SHRINK_GC_BUFFERS_DELAY 4000 // ms
// The amount of time we wait from the first request to GC to actually
// doing the first GC.
#define NS_FIRST_GC_DELAY 10000 // ms
#define NS_FULL_GC_DELAY 60000 // ms
// Maximum amount of time that should elapse between incremental GC slices
#define NS_INTERSLICE_GC_DELAY 100 // ms
// If we haven't painted in 100ms, we allow for a longer GC budget
#define NS_INTERSLICE_GC_BUDGET 40 // ms
// The amount of time we wait between a request to CC (after GC ran)
// and doing the actual CC.
#define NS_CC_DELAY 6000 // ms
#define NS_CC_SKIPPABLE_DELAY 250 // ms
// Maximum amount of time that should elapse between incremental CC slices
static const int64_t kICCIntersliceDelay = 32; // ms
// Time budget for an incremental CC slice
static const int64_t kICCSliceBudget = 5; // ms
// Maximum total duration for an ICC
static const uint32_t kMaxICCDuration = 2000; // ms
// Force a CC after this long if there's more than NS_CC_FORCED_PURPLE_LIMIT
// objects in the purple buffer.
#define NS_CC_FORCED (2 * 60 * PR_USEC_PER_SEC) // 2 min
#define NS_CC_FORCED_PURPLE_LIMIT 10
// Don't allow an incremental GC to lock out the CC for too long.
#define NS_MAX_CC_LOCKEDOUT_TIME (15 * PR_USEC_PER_SEC) // 15 seconds
// Trigger a CC if the purple buffer exceeds this size when we check it.
#define NS_CC_PURPLE_LIMIT 200
#define JAVASCRIPT nsIProgrammingLanguage::JAVASCRIPT
// Large value used to specify that a script should run essentially forever
#define NS_UNLIMITED_SCRIPT_RUNTIME (0x40000000LL << 32)
// if you add statics here, add them to the list in StartupJSEnvironment
static nsITimer *sGCTimer;
static nsITimer *sShrinkGCBuffersTimer;
static nsITimer *sCCTimer;
static nsITimer *sICCTimer;
static nsITimer *sFullGCTimer;
static nsITimer *sInterSliceGCTimer;
static TimeStamp sLastCCEndTime;
static bool sCCLockedOut;
static PRTime sCCLockedOutTime;
static JS::GCSliceCallback sPrevGCSliceCallback;
static bool sHasRunGC;
// The number of currently pending document loads. This count isn't
// guaranteed to always reflect reality and can't easily as we don't
// have an easy place to know when a load ends or is interrupted in
// all cases. This counter also gets reset if we end up GC'ing while
// we're waiting for a slow page to load. IOW, this count may be 0
// even when there are pending loads.
static uint32_t sPendingLoadCount;
static bool sLoadingInProgress;
static uint32_t sCCollectedWaitingForGC;
static uint32_t sCCollectedZonesWaitingForGC;
static uint32_t sLikelyShortLivingObjectsNeedingGC;
static bool sPostGCEventsToConsole;
static bool sPostGCEventsToObserver;
static int32_t sCCTimerFireCount = 0;
static uint32_t sMinForgetSkippableTime = UINT32_MAX;
static uint32_t sMaxForgetSkippableTime = 0;
static uint32_t sTotalForgetSkippableTime = 0;
static uint32_t sRemovedPurples = 0;
static uint32_t sForgetSkippableBeforeCC = 0;
static uint32_t sPreviousSuspectedCount = 0;
static uint32_t sCleanupsSinceLastGC = UINT32_MAX;
static bool sNeedsFullCC = false;
static bool sNeedsGCAfterCC = false;
static bool sIncrementalCC = false;
static bool sDidPaintAfterPreviousICCSlice = false;
static nsScriptNameSpaceManager *gNameSpaceManager;
static nsIJSRuntimeService *sRuntimeService;
static const char kJSRuntimeServiceContractID[] =
"@mozilla.org/js/xpc/RuntimeService;1";
static PRTime sFirstCollectionTime;
static JSRuntime *sRuntime;
static bool sIsInitialized;
static bool sDidShutdown;
static bool sShuttingDown;
static int32_t sContextCount;
static nsIScriptSecurityManager *sSecurityManager;
// nsJSEnvironmentObserver observes the memory-pressure notifications
// and forces a garbage collection and cycle collection when it happens, if
// the appropriate pref is set.
static bool sGCOnMemoryPressure;
// In testing, we call RunNextCollectorTimer() to ensure that the collectors are run more
// aggressively than they would be in regular browsing. sExpensiveCollectorPokes keeps
// us from triggering expensive full collections too frequently.
static int32_t sExpensiveCollectorPokes = 0;
static const int32_t kPokesBetweenExpensiveCollectorTriggers = 5;
static PRTime
GetCollectionTimeDelta()
{
PRTime now = PR_Now();
if (sFirstCollectionTime) {
return now - sFirstCollectionTime;
}
sFirstCollectionTime = now;
return 0;
}
static void
KillTimers()
{
nsJSContext::KillGCTimer();
nsJSContext::KillShrinkGCBuffersTimer();
nsJSContext::KillCCTimer();
nsJSContext::KillICCTimer();
nsJSContext::KillFullGCTimer();
nsJSContext::KillInterSliceGCTimer();
}
// If we collected a substantial amount of cycles, poke the GC since more objects
// might be unreachable now.
static bool
NeedsGCAfterCC()
{
return sCCollectedWaitingForGC > 250 ||
sCCollectedZonesWaitingForGC > 0 ||
sLikelyShortLivingObjectsNeedingGC > 2500 ||
sNeedsGCAfterCC;
}
class nsJSEnvironmentObserver final : public nsIObserver
{
~nsJSEnvironmentObserver() {}
public:
NS_DECL_ISUPPORTS
NS_DECL_NSIOBSERVER
};
NS_IMPL_ISUPPORTS(nsJSEnvironmentObserver, nsIObserver)
NS_IMETHODIMP
nsJSEnvironmentObserver::Observe(nsISupports* aSubject, const char* aTopic,
const char16_t* aData)
{
if (sGCOnMemoryPressure && !nsCRT::strcmp(aTopic, "memory-pressure")) {
if(StringBeginsWith(nsDependentString(aData),
NS_LITERAL_STRING("low-memory-ongoing"))) {
// Don't GC/CC if we are in an ongoing low-memory state since its very
// slow and it likely won't help us anyway.
return NS_OK;
}
nsJSContext::GarbageCollectNow(JS::gcreason::MEM_PRESSURE,
nsJSContext::NonIncrementalGC,
nsJSContext::ShrinkingGC);
nsJSContext::CycleCollectNow();
if (NeedsGCAfterCC()) {
nsJSContext::GarbageCollectNow(JS::gcreason::MEM_PRESSURE,
nsJSContext::NonIncrementalGC,
nsJSContext::ShrinkingGC);
}
} else if (!nsCRT::strcmp(aTopic, "quit-application") ||
!nsCRT::strcmp(aTopic, NS_XPCOM_SHUTDOWN_OBSERVER_ID)) {
sShuttingDown = true;
KillTimers();
}
return NS_OK;
}
/****************************************************************
************************** AutoFree ****************************
****************************************************************/
class AutoFree {
public:
explicit AutoFree(void* aPtr) : mPtr(aPtr) {
}
~AutoFree() {
if (mPtr)
nsMemory::Free(mPtr);
}
void Invalidate() {
mPtr = 0;
}
private:
void *mPtr;
};
// A utility function for script languages to call. Although it looks small,
// the use of nsIDocShell and nsPresContext triggers a huge number of
// dependencies that most languages would not otherwise need.
// XXXmarkh - This function is mis-placed!
bool
NS_HandleScriptError(nsIScriptGlobalObject *aScriptGlobal,
const ErrorEventInit &aErrorEventInit,
nsEventStatus *aStatus)
{
bool called = false;
nsCOMPtr<nsPIDOMWindow> win(do_QueryInterface(aScriptGlobal));
nsIDocShell *docShell = win ? win->GetDocShell() : nullptr;
if (docShell) {
nsRefPtr<nsPresContext> presContext;
docShell->GetPresContext(getter_AddRefs(presContext));
static int32_t errorDepth; // Recursion prevention
++errorDepth;
if (errorDepth < 2) {
// Dispatch() must be synchronous for the recursion block
// (errorDepth) to work.
nsRefPtr<ErrorEvent> event =
ErrorEvent::Constructor(static_cast<nsGlobalWindow*>(win.get()),
NS_LITERAL_STRING("error"),
aErrorEventInit);
event->SetTrusted(true);
EventDispatcher::DispatchDOMEvent(win, nullptr, event, presContext,
aStatus);
called = true;
}
--errorDepth;
}
return called;
}
class ScriptErrorEvent : public nsRunnable
{
public:
ScriptErrorEvent(nsPIDOMWindow* aWindow,
JSRuntime* aRuntime,
xpc::ErrorReport* aReport,
JS::Handle<JS::Value> aError)
: mWindow(aWindow)
, mReport(aReport)
, mError(aRuntime, aError)
{}
NS_IMETHOD Run()
{
nsEventStatus status = nsEventStatus_eIgnore;
nsPIDOMWindow* win = mWindow;
MOZ_ASSERT(win);
// First, notify the DOM that we have a script error, but only if
// our window is still the current inner.
if (win->IsCurrentInnerWindow() && win->GetDocShell() && !sHandlingScriptError) {
AutoRestore<bool> recursionGuard(sHandlingScriptError);
sHandlingScriptError = true;
nsRefPtr<nsPresContext> presContext;
win->GetDocShell()->GetPresContext(getter_AddRefs(presContext));
ThreadsafeAutoJSContext cx;
RootedDictionary<ErrorEventInit> init(cx);
init.mCancelable = true;
init.mFilename = mReport->mFileName;
init.mBubbles = true;
NS_NAMED_LITERAL_STRING(xoriginMsg, "Script error.");
if (!mReport->mIsMuted) {
init.mMessage = mReport->mErrorMsg;
init.mLineno = mReport->mLineNumber;
init.mColno = mReport->mColumn;
init.mError = mError;
} else {
NS_WARNING("Not same origin error!");
init.mMessage = xoriginMsg;
init.mLineno = 0;
}
nsRefPtr<ErrorEvent> event =
ErrorEvent::Constructor(static_cast<nsGlobalWindow*>(win),
NS_LITERAL_STRING("error"), init);
event->SetTrusted(true);
EventDispatcher::DispatchDOMEvent(win, nullptr, event, presContext,
&status);
}
if (status != nsEventStatus_eConsumeNoDefault) {
mReport->LogToConsole();
}
return NS_OK;
}
private:
nsCOMPtr<nsPIDOMWindow> mWindow;
nsRefPtr<xpc::ErrorReport> mReport;
JS::PersistentRootedValue mError;
static bool sHandlingScriptError;
};
bool ScriptErrorEvent::sHandlingScriptError = false;
// This temporarily lives here to avoid code churn. It will go away entirely
// soon.
namespace xpc {
void
SystemErrorReporter(JSContext *cx, const char *message, JSErrorReport *report)
{
JS::Rooted<JS::Value> exception(cx);
::JS_GetPendingException(cx, &exception);
// Note: we must do this before running any more code on cx.
::JS_ClearPendingException(cx);
MOZ_ASSERT(cx == nsContentUtils::GetCurrentJSContext());
nsCOMPtr<nsIGlobalObject> globalObject;
// The eventual plan is for error reporting to happen in the AutoJSAPI
// destructor using the global with which the AutoJSAPI was initialized. We
// can't _quite_ do that yet, so we take a sloppy stab at those semantics. If
// we have an nsIScriptContext, we'll get the right answer modulo
// non-current-inners.
//
// Otherwise, we just use the privileged junk scope. This has the effect of
// causing us to report the error as "chrome javascript" rather than "content
// javascript", and not invoking any error reporters. This is exactly what we
// want here.
if (nsIScriptContext* scx = GetScriptContextFromJSContext(cx)) {
nsCOMPtr<nsPIDOMWindow> outer = do_QueryInterface(scx->GetGlobalObject());
if (outer) {
globalObject = static_cast<nsGlobalWindow*>(outer->GetCurrentInnerWindow());
}
}
// We run addons in a separate privileged compartment, but they still expect
// to trigger the onerror handler of their associated DOMWindow.
//
// Note that the way we do this right now is sloppy. Error reporters can
// theoretically be triggered at arbitrary times (not just immediately before
// an AutoJSAPI comes off the stack), so we don't really have a way of knowing
// that the global of the current compartment is the correct global with which
// to report the error. But in practice this is probably fine for the time
// being, and will get cleaned up soon when we fix bug 981187.
if (!globalObject && JS::CurrentGlobalOrNull(cx)) {
globalObject = xpc::AddonWindowOrNull(JS::CurrentGlobalOrNull(cx));
}
if (!globalObject) {
globalObject = xpc::NativeGlobal(xpc::PrivilegedJunkScope());
}
if (globalObject) {
nsRefPtr<xpc::ErrorReport> xpcReport = new xpc::ErrorReport();
bool isChrome = nsContentUtils::IsSystemPrincipal(globalObject->PrincipalOrNull());
nsCOMPtr<nsPIDOMWindow> win = do_QueryInterface(globalObject);
xpcReport->Init(report, message, isChrome, win ? win->WindowID() : 0);
// If we can't dispatch an event to a window, report it to the console
// directly. This includes the case where the error was an OOM, because
// triggering a scripted event handler is likely to generate further OOMs.
if (!win || JSREPORT_IS_WARNING(xpcReport->mFlags) ||
report->errorNumber == JSMSG_OUT_OF_MEMORY)
{
xpcReport->LogToConsole();
return;
}
// Otherwise, we need to asynchronously invoke onerror before we can decide
// whether or not to report the error to the console.
DispatchScriptErrorEvent(win, JS_GetRuntime(cx), xpcReport, exception);
}
}
void
DispatchScriptErrorEvent(nsPIDOMWindow *win, JSRuntime *rt, xpc::ErrorReport *xpcReport,
JS::Handle<JS::Value> exception)
{
nsContentUtils::AddScriptRunner(new ScriptErrorEvent(win, rt, xpcReport, exception));
}
} /* namespace xpc */
#ifdef DEBUG
// A couple of useful functions to call when you're debugging.
nsGlobalWindow *
JSObject2Win(JSObject *obj)
{
return xpc::WindowOrNull(obj);
}
void
PrintWinURI(nsGlobalWindow *win)
{
if (!win) {
printf("No window passed in.\n");
return;
}
nsCOMPtr<nsIDocument> doc = win->GetExtantDoc();
if (!doc) {
printf("No document in the window.\n");
return;
}
nsIURI *uri = doc->GetDocumentURI();
if (!uri) {
printf("Document doesn't have a URI.\n");
return;
}
nsAutoCString spec;
uri->GetSpec(spec);
printf("%s\n", spec.get());
}
void
PrintWinCodebase(nsGlobalWindow *win)
{
if (!win) {
printf("No window passed in.\n");
return;
}
nsIPrincipal *prin = win->GetPrincipal();
if (!prin) {
printf("Window doesn't have principals.\n");
return;
}
nsCOMPtr<nsIURI> uri;
prin->GetURI(getter_AddRefs(uri));
if (!uri) {
printf("No URI, maybe the system principal.\n");
return;
}
nsAutoCString spec;
uri->GetSpec(spec);
printf("%s\n", spec.get());
}
void
DumpString(const nsAString &str)
{
printf("%s\n", NS_ConvertUTF16toUTF8(str).get());
}
#endif
#define JS_OPTIONS_DOT_STR "javascript.options."
static const char js_options_dot_str[] = JS_OPTIONS_DOT_STR;
#ifdef JS_GC_ZEAL
static const char js_zeal_option_str[] = JS_OPTIONS_DOT_STR "gczeal";
static const char js_zeal_frequency_str[] = JS_OPTIONS_DOT_STR "gczeal.frequency";
#endif
static const char js_memlog_option_str[] = JS_OPTIONS_DOT_STR "mem.log";
static const char js_memnotify_option_str[] = JS_OPTIONS_DOT_STR "mem.notify";
void
nsJSContext::JSOptionChangedCallback(const char *pref, void *data)
{
sPostGCEventsToConsole = Preferences::GetBool(js_memlog_option_str);
sPostGCEventsToObserver = Preferences::GetBool(js_memnotify_option_str);
#ifdef JS_GC_ZEAL
nsJSContext *context = reinterpret_cast<nsJSContext *>(data);
int32_t zeal = Preferences::GetInt(js_zeal_option_str, -1);
int32_t frequency = Preferences::GetInt(js_zeal_frequency_str, JS_DEFAULT_ZEAL_FREQ);
if (zeal >= 0)
::JS_SetGCZeal(context->mContext, (uint8_t)zeal, frequency);
#endif
}
nsJSContext::nsJSContext(bool aGCOnDestruction,
nsIScriptGlobalObject* aGlobalObject)
: mWindowProxy(nullptr)
, mGCOnDestruction(aGCOnDestruction)
, mGlobalObjectRef(aGlobalObject)
{
EnsureStatics();
++sContextCount;
mContext = ::JS_NewContext(sRuntime, gStackSize);
if (mContext) {
::JS_SetContextPrivate(mContext, static_cast<nsIScriptContext *>(this));
// Make sure the new context gets the default context options
JS::ContextOptionsRef(mContext).setPrivateIsNSISupports(true);
// Watch for the JS boolean options
Preferences::RegisterCallback(JSOptionChangedCallback,
js_options_dot_str, this);
}
mIsInitialized = false;
mProcessingScriptTag = false;
HoldJSObjects(this);
}
nsJSContext::~nsJSContext()
{
mGlobalObjectRef = nullptr;
DestroyJSContext();
--sContextCount;
if (!sContextCount && sDidShutdown) {
// The last context is being deleted, and we're already in the
// process of shutting down, release the JS runtime service, and
// the security manager.
NS_IF_RELEASE(sRuntimeService);
NS_IF_RELEASE(sSecurityManager);
}
}
// This function is called either by the destructor or unlink, which means that
// it can never be called when there is an outstanding ref to the
// nsIScriptContext on the stack. Our stack-scoped cx pushers hold such a ref,
// so we can assume here that mContext is not on the stack (and therefore not
// in use).
void
nsJSContext::DestroyJSContext()
{
if (!mContext) {
return;
}
// Clear our entry in the JSContext, bugzilla bug 66413
::JS_SetContextPrivate(mContext, nullptr);
// Unregister our "javascript.options.*" pref-changed callback.
Preferences::UnregisterCallback(JSOptionChangedCallback,
js_options_dot_str, this);
if (mGCOnDestruction) {
PokeGC(JS::gcreason::NSJSCONTEXT_DESTROY);
}
JS_DestroyContextNoGC(mContext);
mContext = nullptr;
DropJSObjects(this);
}
// QueryInterface implementation for nsJSContext
NS_IMPL_CYCLE_COLLECTION_CLASS(nsJSContext)
NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(nsJSContext)
NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mWindowProxy)
NS_IMPL_CYCLE_COLLECTION_TRACE_END
NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(nsJSContext)
NS_ASSERTION(!tmp->mContext || !js::ContextHasOutstandingRequests(tmp->mContext),
"Trying to unlink a context with outstanding requests.");
tmp->mIsInitialized = false;
tmp->mGCOnDestruction = false;
tmp->mWindowProxy = nullptr;
tmp->DestroyJSContext();
NS_IMPL_CYCLE_COLLECTION_UNLINK(mGlobalObjectRef)
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INTERNAL(nsJSContext)
NS_IMPL_CYCLE_COLLECTION_DESCRIBE(nsJSContext, tmp->GetCCRefcnt())
NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mGlobalObjectRef)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_SCRIPT_OBJECTS
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(nsJSContext)
NS_INTERFACE_MAP_ENTRY(nsIScriptContext)
NS_INTERFACE_MAP_ENTRY(nsISupports)
NS_INTERFACE_MAP_END
NS_IMPL_CYCLE_COLLECTING_ADDREF(nsJSContext)
NS_IMPL_CYCLE_COLLECTING_RELEASE(nsJSContext)
nsrefcnt
nsJSContext::GetCCRefcnt()
{
nsrefcnt refcnt = mRefCnt.get();
// In the (abnormal) case of synchronous cycle-collection, the context may be
// actively running JS code in which case we must keep it alive by adding an
// extra refcount.
if (mContext && js::ContextHasOutstandingRequests(mContext)) {
refcnt++;
}
return refcnt;
}
#ifdef DEBUG
bool
AtomIsEventHandlerName(nsIAtom *aName)
{
const char16_t *name = aName->GetUTF16String();
const char16_t *cp;
char16_t c;
for (cp = name; *cp != '\0'; ++cp)
{
c = *cp;
if ((c < 'A' || c > 'Z') && (c < 'a' || c > 'z'))
return false;
}
return true;
}
#endif
nsIScriptGlobalObject *
nsJSContext::GetGlobalObject()
{
// Note: this could probably be simplified somewhat more; see bug 974327
// comments 1 and 3.
if (!mWindowProxy) {
return nullptr;
}
MOZ_ASSERT(mGlobalObjectRef);
return mGlobalObjectRef;
}
JSContext*
nsJSContext::GetNativeContext()
{
return mContext;
}
nsresult
nsJSContext::InitContext()
{
// Make sure callers of this use
// WillInitializeContext/DidInitializeContext around this call.
NS_ENSURE_TRUE(!mIsInitialized, NS_ERROR_ALREADY_INITIALIZED);
if (!mContext)
return NS_ERROR_OUT_OF_MEMORY;
JSOptionChangedCallback(js_options_dot_str, this);
return NS_OK;
}
nsresult
nsJSContext::SetProperty(JS::Handle<JSObject*> aTarget, const char* aPropName, nsISupports* aArgs)
{
AutoJSAPI jsapi;
if (NS_WARN_IF(!jsapi.InitWithLegacyErrorReporting(GetGlobalObject()))) {
return NS_ERROR_FAILURE;
}
MOZ_ASSERT(jsapi.cx() == mContext,
"AutoJSAPI should have found our own JSContext*");
JS::AutoValueVector args(mContext);
JS::Rooted<JSObject*> global(mContext, GetWindowProxy());
nsresult rv =
ConvertSupportsTojsvals(aArgs, global, args);
NS_ENSURE_SUCCESS(rv, rv);
// got the arguments, now attach them.
for (uint32_t i = 0; i < args.length(); ++i) {
if (!JS_WrapValue(mContext, args[i])) {
return NS_ERROR_FAILURE;
}
}
JS::Rooted<JSObject*> array(mContext, ::JS_NewArrayObject(mContext, args));
if (!array) {
return NS_ERROR_FAILURE;
}
return JS_DefineProperty(mContext, aTarget, aPropName, array, 0) ? NS_OK : NS_ERROR_FAILURE;
}
nsresult
nsJSContext::ConvertSupportsTojsvals(nsISupports* aArgs,
JS::Handle<JSObject*> aScope,
JS::AutoValueVector& aArgsOut)
{
nsresult rv = NS_OK;
// If the array implements nsIJSArgArray, copy the contents and return.
nsCOMPtr<nsIJSArgArray> fastArray = do_QueryInterface(aArgs);
if (fastArray) {
uint32_t argc;
JS::Value* argv;
rv = fastArray->GetArgs(&argc, reinterpret_cast<void **>(&argv));
if (NS_SUCCEEDED(rv) && !aArgsOut.append(argv, argc)) {
rv = NS_ERROR_OUT_OF_MEMORY;
}
return rv;
}
// Take the slower path converting each item.
// Handle only nsIArray and nsIVariant. nsIArray is only needed for
// SetProperty('arguments', ...);
nsIXPConnect *xpc = nsContentUtils::XPConnect();
NS_ENSURE_TRUE(xpc, NS_ERROR_UNEXPECTED);
AutoJSContext cx;
if (!aArgs)
return NS_OK;
uint32_t argCount;
// This general purpose function may need to convert an arg array
// (window.arguments, event-handler args) and a generic property.
nsCOMPtr<nsIArray> argsArray(do_QueryInterface(aArgs));
if (argsArray) {
rv = argsArray->GetLength(&argCount);
NS_ENSURE_SUCCESS(rv, rv);
if (argCount == 0)
return NS_OK;
} else {
argCount = 1; // the nsISupports which is not an array
}
// Use the caller's auto guards to release and unroot.
if (!aArgsOut.resize(argCount)) {
return NS_ERROR_OUT_OF_MEMORY;
}
if (argsArray) {
for (uint32_t argCtr = 0; argCtr < argCount && NS_SUCCEEDED(rv); argCtr++) {
nsCOMPtr<nsISupports> arg;
JS::MutableHandle<JS::Value> thisVal = aArgsOut[argCtr];
argsArray->QueryElementAt(argCtr, NS_GET_IID(nsISupports),
getter_AddRefs(arg));
if (!arg) {
thisVal.setNull();
continue;
}
nsCOMPtr<nsIVariant> variant(do_QueryInterface(arg));
if (variant != nullptr) {
rv = xpc->VariantToJS(cx, aScope, variant, thisVal);
} else {
// And finally, support the nsISupportsPrimitives supplied
// by the AppShell. It generally will pass only strings, but
// as we have code for handling all, we may as well use it.
rv = AddSupportsPrimitiveTojsvals(arg, thisVal.address());
if (rv == NS_ERROR_NO_INTERFACE) {
// something else - probably an event object or similar -
// just wrap it.
#ifdef DEBUG
// but first, check its not another nsISupportsPrimitive, as
// these are now deprecated for use with script contexts.
nsCOMPtr<nsISupportsPrimitive> prim(do_QueryInterface(arg));
NS_ASSERTION(prim == nullptr,
"Don't pass nsISupportsPrimitives - use nsIVariant!");
#endif
JSAutoCompartment ac(cx, aScope);
rv = nsContentUtils::WrapNative(cx, arg, thisVal);
}
}
}
} else {
nsCOMPtr<nsIVariant> variant = do_QueryInterface(aArgs);
if (variant) {
rv = xpc->VariantToJS(cx, aScope, variant, aArgsOut[0]);
} else {
NS_ERROR("Not an array, not an interface?");
rv = NS_ERROR_UNEXPECTED;
}
}
return rv;
}
// This really should go into xpconnect somewhere...
nsresult
nsJSContext::AddSupportsPrimitiveTojsvals(nsISupports *aArg, JS::Value *aArgv)
{
NS_PRECONDITION(aArg, "Empty arg");
nsCOMPtr<nsISupportsPrimitive> argPrimitive(do_QueryInterface(aArg));
if (!argPrimitive)
return NS_ERROR_NO_INTERFACE;
AutoJSContext cx;
uint16_t type;
argPrimitive->GetType(&type);
switch(type) {
case nsISupportsPrimitive::TYPE_CSTRING : {
nsCOMPtr<nsISupportsCString> p(do_QueryInterface(argPrimitive));
NS_ENSURE_TRUE(p, NS_ERROR_UNEXPECTED);
nsAutoCString data;
p->GetData(data);
JSString *str = ::JS_NewStringCopyN(cx, data.get(), data.Length());
NS_ENSURE_TRUE(str, NS_ERROR_OUT_OF_MEMORY);
*aArgv = STRING_TO_JSVAL(str);
break;
}
case nsISupportsPrimitive::TYPE_STRING : {
nsCOMPtr<nsISupportsString> p(do_QueryInterface(argPrimitive));
NS_ENSURE_TRUE(p, NS_ERROR_UNEXPECTED);
nsAutoString data;
p->GetData(data);
// cast is probably safe since wchar_t and char16_t are expected
// to be equivalent; both unsigned 16-bit entities
JSString *str =
::JS_NewUCStringCopyN(cx, data.get(), data.Length());
NS_ENSURE_TRUE(str, NS_ERROR_OUT_OF_MEMORY);
*aArgv = STRING_TO_JSVAL(str);
break;
}
case nsISupportsPrimitive::TYPE_PRBOOL : {
nsCOMPtr<nsISupportsPRBool> p(do_QueryInterface(argPrimitive));
NS_ENSURE_TRUE(p, NS_ERROR_UNEXPECTED);
bool data;
p->GetData(&data);
*aArgv = BOOLEAN_TO_JSVAL(data);
break;
}
case nsISupportsPrimitive::TYPE_PRUINT8 : {
nsCOMPtr<nsISupportsPRUint8> p(do_QueryInterface(argPrimitive));
NS_ENSURE_TRUE(p, NS_ERROR_UNEXPECTED);
uint8_t data;
p->GetData(&data);
*aArgv = INT_TO_JSVAL(data);
break;
}
case nsISupportsPrimitive::TYPE_PRUINT16 : {
nsCOMPtr<nsISupportsPRUint16> p(do_QueryInterface(argPrimitive));
NS_ENSURE_TRUE(p, NS_ERROR_UNEXPECTED);
uint16_t data;
p->GetData(&data);
*aArgv = INT_TO_JSVAL(data);
break;
}
case nsISupportsPrimitive::TYPE_PRUINT32 : {
nsCOMPtr<nsISupportsPRUint32> p(do_QueryInterface(argPrimitive));
NS_ENSURE_TRUE(p, NS_ERROR_UNEXPECTED);
uint32_t data;
p->GetData(&data);
*aArgv = INT_TO_JSVAL(data);
break;
}
case nsISupportsPrimitive::TYPE_CHAR : {
nsCOMPtr<nsISupportsChar> p(do_QueryInterface(argPrimitive));
NS_ENSURE_TRUE(p, NS_ERROR_UNEXPECTED);
char data;
p->GetData(&data);
JSString *str = ::JS_NewStringCopyN(cx, &data, 1);
NS_ENSURE_TRUE(str, NS_ERROR_OUT_OF_MEMORY);
*aArgv = STRING_TO_JSVAL(str);
break;
}
case nsISupportsPrimitive::TYPE_PRINT16 : {
nsCOMPtr<nsISupportsPRInt16> p(do_QueryInterface(argPrimitive));
NS_ENSURE_TRUE(p, NS_ERROR_UNEXPECTED);
int16_t data;
p->GetData(&data);
*aArgv = INT_TO_JSVAL(data);
break;
}
case nsISupportsPrimitive::TYPE_PRINT32 : {
nsCOMPtr<nsISupportsPRInt32> p(do_QueryInterface(argPrimitive));
NS_ENSURE_TRUE(p, NS_ERROR_UNEXPECTED);
int32_t data;
p->GetData(&data);
*aArgv = INT_TO_JSVAL(data);
break;
}
case nsISupportsPrimitive::TYPE_FLOAT : {
nsCOMPtr<nsISupportsFloat> p(do_QueryInterface(argPrimitive));
NS_ENSURE_TRUE(p, NS_ERROR_UNEXPECTED);
float data;
p->GetData(&data);
*aArgv = ::JS_NumberValue(data);
break;
}
case nsISupportsPrimitive::TYPE_DOUBLE : {
nsCOMPtr<nsISupportsDouble> p(do_QueryInterface(argPrimitive));
NS_ENSURE_TRUE(p, NS_ERROR_UNEXPECTED);
double data;
p->GetData(&data);
*aArgv = ::JS_NumberValue(data);
break;
}
case nsISupportsPrimitive::TYPE_INTERFACE_POINTER : {
nsCOMPtr<nsISupportsInterfacePointer> p(do_QueryInterface(argPrimitive));
NS_ENSURE_TRUE(p, NS_ERROR_UNEXPECTED);
nsCOMPtr<nsISupports> data;
nsIID *iid = nullptr;
p->GetData(getter_AddRefs(data));
p->GetDataIID(&iid);
NS_ENSURE_TRUE(iid, NS_ERROR_UNEXPECTED);
AutoFree iidGuard(iid); // Free iid upon destruction.
JS::Rooted<JSObject*> scope(cx, GetWindowProxy());
JS::Rooted<JS::Value> v(cx);
JSAutoCompartment ac(cx, scope);
nsresult rv = nsContentUtils::WrapNative(cx, data, iid, &v);
NS_ENSURE_SUCCESS(rv, rv);
*aArgv = v;
break;
}
case nsISupportsPrimitive::TYPE_ID :
case nsISupportsPrimitive::TYPE_PRUINT64 :
case nsISupportsPrimitive::TYPE_PRINT64 :
case nsISupportsPrimitive::TYPE_PRTIME :
case nsISupportsPrimitive::TYPE_VOID : {
NS_WARNING("Unsupported primitive type used");
*aArgv = JSVAL_NULL;
break;
}
default : {
NS_WARNING("Unknown primitive type used");
*aArgv = JSVAL_NULL;
break;
}
}
return NS_OK;
}
#ifdef MOZ_JPROF
#include <signal.h>
inline bool
IsJProfAction(struct sigaction *action)
{
return (action->sa_sigaction &&
(action->sa_flags & (SA_RESTART | SA_SIGINFO)) == (SA_RESTART | SA_SIGINFO));
}
void NS_JProfStartProfiling();
void NS_JProfStopProfiling();
void NS_JProfClearCircular();
static bool
JProfStartProfilingJS(JSContext *cx, unsigned argc, JS::Value *vp)
{
NS_JProfStartProfiling();
return true;
}
void NS_JProfStartProfiling()
{
// Figure out whether we're dealing with SIGPROF, SIGALRM, or
// SIGPOLL profiling (SIGALRM for JP_REALTIME, SIGPOLL for
// JP_RTC_HZ)
struct sigaction action;
// Must check ALRM before PROF since both are enabled for real-time
sigaction(SIGALRM, nullptr, &action);
//printf("SIGALRM: %p, flags = %x\n",action.sa_sigaction,action.sa_flags);
if (IsJProfAction(&action)) {
//printf("Beginning real-time jprof profiling.\n");
raise(SIGALRM);
return;
}
sigaction(SIGPROF, nullptr, &action);
//printf("SIGPROF: %p, flags = %x\n",action.sa_sigaction,action.sa_flags);
if (IsJProfAction(&action)) {
//printf("Beginning process-time jprof profiling.\n");
raise(SIGPROF);
return;
}
sigaction(SIGPOLL, nullptr, &action);
//printf("SIGPOLL: %p, flags = %x\n",action.sa_sigaction,action.sa_flags);
if (IsJProfAction(&action)) {
//printf("Beginning rtc-based jprof profiling.\n");
raise(SIGPOLL);
return;
}
printf("Could not start jprof-profiling since JPROF_FLAGS was not set.\n");
}
static bool
JProfStopProfilingJS(JSContext *cx, unsigned argc, JS::Value *vp)
{
NS_JProfStopProfiling();
return true;
}
void
NS_JProfStopProfiling()
{
raise(SIGUSR1);
//printf("Stopped jprof profiling.\n");
}
static bool
JProfClearCircularJS(JSContext *cx, unsigned argc, JS::Value *vp)
{
NS_JProfClearCircular();
return true;
}
void
NS_JProfClearCircular()
{
raise(SIGUSR2);
//printf("cleared jprof buffer\n");
}
static bool
JProfSaveCircularJS(JSContext *cx, unsigned argc, JS::Value *vp)
{
// Not ideal...
NS_JProfStopProfiling();
NS_JProfStartProfiling();
return true;
}
static const JSFunctionSpec JProfFunctions[] = {
JS_FS("JProfStartProfiling", JProfStartProfilingJS, 0, 0),
JS_FS("JProfStopProfiling", JProfStopProfilingJS, 0, 0),
JS_FS("JProfClearCircular", JProfClearCircularJS, 0, 0),
JS_FS("JProfSaveCircular", JProfSaveCircularJS, 0, 0),
JS_FS_END
};
#endif /* defined(MOZ_JPROF) */
nsresult
nsJSContext::InitClasses(JS::Handle<JSObject*> aGlobalObj)
{
JSOptionChangedCallback(js_options_dot_str, this);
AutoJSAPI jsapi;
jsapi.Init();
JSContext* cx = jsapi.cx();
JSAutoCompartment ac(cx, aGlobalObj);
// Attempt to initialize profiling functions
::JS_DefineProfilingFunctions(cx, aGlobalObj);
#ifdef MOZ_JPROF
// Attempt to initialize JProf functions
::JS_DefineFunctions(cx, aGlobalObj, JProfFunctions);
#endif
return NS_OK;
}
void
nsJSContext::WillInitializeContext()
{
mIsInitialized = false;
}
void
nsJSContext::DidInitializeContext()
{
mIsInitialized = true;
}
bool
nsJSContext::IsContextInitialized()
{
return mIsInitialized;
}
bool
nsJSContext::GetProcessingScriptTag()
{
return mProcessingScriptTag;
}
void
nsJSContext::SetProcessingScriptTag(bool aFlag)
{
mProcessingScriptTag = aFlag;
}
void
FullGCTimerFired(nsITimer* aTimer, void* aClosure)
{
nsJSContext::KillFullGCTimer();
MOZ_ASSERT(!aClosure, "Don't pass a closure to FullGCTimerFired");
nsJSContext::GarbageCollectNow(JS::gcreason::FULL_GC_TIMER,
nsJSContext::IncrementalGC);
}
//static
void
nsJSContext::GarbageCollectNow(JS::gcreason::Reason aReason,
IsIncremental aIncremental,
IsShrinking aShrinking,
int64_t aSliceMillis)
{
PROFILER_LABEL("nsJSContext", "GarbageCollectNow",
js::ProfileEntry::Category::GC);
MOZ_ASSERT_IF(aSliceMillis, aIncremental == IncrementalGC);
KillGCTimer();
KillShrinkGCBuffersTimer();
// Reset sPendingLoadCount in case the timer that fired was a
// timer we scheduled due to a normal GC timer firing while
// documents were loading. If this happens we're waiting for a
// document that is taking a long time to load, and we effectively
// ignore the fact that the currently loading documents are still
// loading and move on as if they weren't.
sPendingLoadCount = 0;
sLoadingInProgress = false;
if (!nsContentUtils::XPConnect() || !sRuntime) {
return;
}
if (sCCLockedOut && aIncremental == IncrementalGC) {
// We're in the middle of incremental GC. Do another slice.
JS::PrepareForIncrementalGC(sRuntime);
JS::IncrementalGCSlice(sRuntime, aReason, aSliceMillis);
return;
}
JS::PrepareForFullGC(sRuntime);
if (aIncremental == IncrementalGC) {
MOZ_ASSERT(aShrinking == NonShrinkingGC);
JS::StartIncrementalGC(sRuntime, GC_NORMAL, aReason, aSliceMillis);
} else {
JSGCInvocationKind gckind = aShrinking == ShrinkingGC ? GC_SHRINK : GC_NORMAL;
JS::GCForReason(sRuntime, gckind, aReason);
}
}
//static
void
nsJSContext::ShrinkGCBuffersNow()
{
PROFILER_LABEL("nsJSContext", "ShrinkGCBuffersNow",
js::ProfileEntry::Category::GC);
KillShrinkGCBuffersTimer();
JS::ShrinkGCBuffers(sRuntime);
}
static void
FinishAnyIncrementalGC()
{
if (sCCLockedOut) {
// We're in the middle of an incremental GC, so finish it.
JS::PrepareForIncrementalGC(sRuntime);
JS::FinishIncrementalGC(sRuntime, JS::gcreason::CC_FORCED);
}
}
static void
FireForgetSkippable(uint32_t aSuspected, bool aRemoveChildless)
{
PRTime startTime = PR_Now();
FinishAnyIncrementalGC();
bool earlyForgetSkippable =
sCleanupsSinceLastGC < NS_MAJOR_FORGET_SKIPPABLE_CALLS;
nsCycleCollector_forgetSkippable(aRemoveChildless, earlyForgetSkippable);
sPreviousSuspectedCount = nsCycleCollector_suspectedCount();
++sCleanupsSinceLastGC;
PRTime delta = PR_Now() - startTime;
if (sMinForgetSkippableTime > delta) {
sMinForgetSkippableTime = delta;
}
if (sMaxForgetSkippableTime < delta) {
sMaxForgetSkippableTime = delta;
}
sTotalForgetSkippableTime += delta;
sRemovedPurples += (aSuspected - sPreviousSuspectedCount);
++sForgetSkippableBeforeCC;
}
MOZ_ALWAYS_INLINE
static uint32_t
TimeBetween(TimeStamp start, TimeStamp end)
{
MOZ_ASSERT(end >= start);
return (uint32_t) ((end - start).ToMilliseconds());
}
static uint32_t
TimeUntilNow(TimeStamp start)
{
if (start.IsNull()) {
return 0;
}
return TimeBetween(start, TimeStamp::Now());
}
struct CycleCollectorStats
{
void Init()
{
Clear();
mMaxSliceTimeSinceClear = 0;
}
void Clear()
{
mBeginSliceTime = TimeStamp();
mEndSliceTime = TimeStamp();
mBeginTime = TimeStamp();
mMaxGCDuration = 0;
mRanSyncForgetSkippable = false;
mSuspected = 0;
mMaxSkippableDuration = 0;
mMaxSliceTime = 0;
mTotalSliceTime = 0;
mAnyLockedOut = false;
mExtraForgetSkippableCalls = 0;
}
void PrepareForCycleCollectionSlice(int32_t aExtraForgetSkippableCalls = 0);
void FinishCycleCollectionSlice()
{
if (mBeginSliceTime.IsNull()) {
// We already called this method from EndCycleCollectionCallback for this slice.
return;
}
mEndSliceTime = TimeStamp::Now();
uint32_t sliceTime = TimeBetween(mBeginSliceTime, mEndSliceTime);
mMaxSliceTime = std::max(mMaxSliceTime, sliceTime);
mMaxSliceTimeSinceClear = std::max(mMaxSliceTimeSinceClear, sliceTime);
mTotalSliceTime += sliceTime;
mBeginSliceTime = TimeStamp();
MOZ_ASSERT(mExtraForgetSkippableCalls == 0, "Forget to reset extra forget skippable calls?");
}
void RunForgetSkippable();
// Time the current slice began, including any GC finishing.
TimeStamp mBeginSliceTime;
// Time the previous slice of the current CC ended.
TimeStamp mEndSliceTime;
// Time the current cycle collection began.
TimeStamp mBeginTime;
// The longest GC finishing duration for any slice of the current CC.
uint32_t mMaxGCDuration;
// True if we ran sync forget skippable in any slice of the current CC.
bool mRanSyncForgetSkippable;
// Number of suspected objects at the start of the current CC.
uint32_t mSuspected;
// The longest duration spent on sync forget skippable in any slice of the
// current CC.
uint32_t mMaxSkippableDuration;
// The longest pause of any slice in the current CC.
uint32_t mMaxSliceTime;
// The longest slice time since ClearMaxCCSliceTime() was called.
uint32_t mMaxSliceTimeSinceClear;
// The total amount of time spent actually running the current CC.
uint32_t mTotalSliceTime;
// True if we were locked out by the GC in any slice of the current CC.
bool mAnyLockedOut;
int32_t mExtraForgetSkippableCalls;
};
CycleCollectorStats gCCStats;
void
CycleCollectorStats::PrepareForCycleCollectionSlice(int32_t aExtraForgetSkippableCalls)
{
mBeginSliceTime = TimeStamp::Now();
// Before we begin the cycle collection, make sure there is no active GC.
if (sCCLockedOut) {
mAnyLockedOut = true;
FinishAnyIncrementalGC();
uint32_t gcTime = TimeBetween(mBeginSliceTime, TimeStamp::Now());
mMaxGCDuration = std::max(mMaxGCDuration, gcTime);
}
mExtraForgetSkippableCalls = aExtraForgetSkippableCalls;
}
void
CycleCollectorStats::RunForgetSkippable()
{
// Run forgetSkippable synchronously to reduce the size of the CC graph. This
// is particularly useful if we recently finished a GC.
if (mExtraForgetSkippableCalls >= 0) {
TimeStamp beginForgetSkippable = TimeStamp::Now();
bool ranSyncForgetSkippable = false;
while (sCleanupsSinceLastGC < NS_MAJOR_FORGET_SKIPPABLE_CALLS) {
FireForgetSkippable(nsCycleCollector_suspectedCount(), false);
ranSyncForgetSkippable = true;
}
for (int32_t i = 0; i < mExtraForgetSkippableCalls; ++i) {
FireForgetSkippable(nsCycleCollector_suspectedCount(), false);
ranSyncForgetSkippable = true;
}
if (ranSyncForgetSkippable) {
mMaxSkippableDuration =
std::max(mMaxSkippableDuration, TimeUntilNow(beginForgetSkippable));
mRanSyncForgetSkippable = true;
}
}
mExtraForgetSkippableCalls = 0;
}
//static
void
nsJSContext::CycleCollectNow(nsICycleCollectorListener *aListener,
int32_t aExtraForgetSkippableCalls)
{
if (!NS_IsMainThread()) {
return;
}
PROFILER_LABEL("nsJSContext", "CycleCollectNow",
js::ProfileEntry::Category::CC);
gCCStats.PrepareForCycleCollectionSlice(aExtraForgetSkippableCalls);
nsCycleCollector_collect(aListener);
gCCStats.FinishCycleCollectionSlice();
}
//static
void
nsJSContext::RunCycleCollectorSlice()
{
if (!NS_IsMainThread()) {
return;
}
PROFILER_LABEL("nsJSContext", "RunCycleCollectorSlice",
js::ProfileEntry::Category::CC);
gCCStats.PrepareForCycleCollectionSlice();
// Decide how long we want to budget for this slice. By default,
// use an unlimited budget.
js::SliceBudget budget;
if (sIncrementalCC) {
if (gCCStats.mBeginTime.IsNull()) {
// If no CC is in progress, use the standard slice time.
budget = js::SliceBudget(js::TimeBudget(kICCSliceBudget));
} else {
TimeStamp now = TimeStamp::Now();
// Only run a limited slice if we're within the max running time.
if (TimeBetween(gCCStats.mBeginTime, now) < kMaxICCDuration) {
float sliceMultiplier = std::max(TimeBetween(gCCStats.mEndSliceTime, now) / (float)kICCIntersliceDelay, 1.0f);
budget = js::SliceBudget(js::TimeBudget(kICCSliceBudget * sliceMultiplier));
}
}
}
nsCycleCollector_collectSlice(budget, sDidPaintAfterPreviousICCSlice);
sDidPaintAfterPreviousICCSlice = false;
gCCStats.FinishCycleCollectionSlice();
}
//static
void
nsJSContext::RunCycleCollectorWorkSlice(int64_t aWorkBudget)
{
if (!NS_IsMainThread()) {
return;
}
PROFILER_LABEL("nsJSContext", "RunCycleCollectorWorkSlice",
js::ProfileEntry::Category::CC);
gCCStats.PrepareForCycleCollectionSlice();
js::SliceBudget budget = js::SliceBudget(js::WorkBudget(aWorkBudget));
nsCycleCollector_collectSlice(budget);
gCCStats.FinishCycleCollectionSlice();
}
void
nsJSContext::ClearMaxCCSliceTime()
{
gCCStats.mMaxSliceTimeSinceClear = 0;
}
uint32_t
nsJSContext::GetMaxCCSliceTimeSinceClear()
{
return gCCStats.mMaxSliceTimeSinceClear;
}
static void
ICCTimerFired(nsITimer* aTimer, void* aClosure)
{
if (sDidShutdown) {
return;
}
// Ignore ICC timer fires during IGC. Running ICC during an IGC will cause us
// to synchronously finish the GC, which is bad.
if (sCCLockedOut) {
PRTime now = PR_Now();
if (sCCLockedOutTime == 0) {
sCCLockedOutTime = now;
return;
}
if (now - sCCLockedOutTime < NS_MAX_CC_LOCKEDOUT_TIME) {
return;
}
}
nsJSContext::RunCycleCollectorSlice();
}
//static
void
nsJSContext::BeginCycleCollectionCallback()
{
MOZ_ASSERT(NS_IsMainThread());
gCCStats.mBeginTime = gCCStats.mBeginSliceTime.IsNull() ? TimeStamp::Now() : gCCStats.mBeginSliceTime;
gCCStats.mSuspected = nsCycleCollector_suspectedCount();
KillCCTimer();
gCCStats.RunForgetSkippable();
MOZ_ASSERT(!sICCTimer, "Tried to create a new ICC timer when one already existed.");
// Create an ICC timer even if ICC is globally disabled, because we could be manually triggering
// an incremental collection, and we want to be sure to finish it.
CallCreateInstance("@mozilla.org/timer;1", &sICCTimer);
if (sICCTimer) {
sICCTimer->InitWithFuncCallback(ICCTimerFired,
nullptr,
kICCIntersliceDelay,
nsITimer::TYPE_REPEATING_SLACK);
}
}
static_assert(NS_GC_DELAY > kMaxICCDuration, "A max duration ICC shouldn't reduce GC delay to 0");
//static
void
nsJSContext::EndCycleCollectionCallback(CycleCollectorResults &aResults)
{
MOZ_ASSERT(NS_IsMainThread());
nsJSContext::KillICCTimer();
// Update timing information for the current slice before we log it, if
// we previously called PrepareForCycleCollectionSlice(). During shutdown
// CCs, this won't happen.
gCCStats.FinishCycleCollectionSlice();
sCCollectedWaitingForGC += aResults.mFreedGCed;
sCCollectedZonesWaitingForGC += aResults.mFreedJSZones;
TimeStamp endCCTimeStamp = TimeStamp::Now();
uint32_t ccNowDuration = TimeBetween(gCCStats.mBeginTime, endCCTimeStamp);
if (NeedsGCAfterCC()) {
PokeGC(JS::gcreason::CC_WAITING,
NS_GC_DELAY - std::min(ccNowDuration, kMaxICCDuration));
}
PRTime endCCTime;
if (sPostGCEventsToObserver) {
endCCTime = PR_Now();
}
// Log information about the CC via telemetry, JSON and the console.
Telemetry::Accumulate(Telemetry::CYCLE_COLLECTOR_FINISH_IGC, gCCStats.mAnyLockedOut);
Telemetry::Accumulate(Telemetry::CYCLE_COLLECTOR_SYNC_SKIPPABLE, gCCStats.mRanSyncForgetSkippable);
Telemetry::Accumulate(Telemetry::CYCLE_COLLECTOR_FULL, ccNowDuration);
Telemetry::Accumulate(Telemetry::CYCLE_COLLECTOR_MAX_PAUSE, gCCStats.mMaxSliceTime);
if (!sLastCCEndTime.IsNull()) {
// TimeBetween returns milliseconds, but we want to report seconds.
uint32_t timeBetween = TimeBetween(sLastCCEndTime, gCCStats.mBeginTime) / 1000;
Telemetry::Accumulate(Telemetry::CYCLE_COLLECTOR_TIME_BETWEEN, timeBetween);
}
sLastCCEndTime = endCCTimeStamp;
Telemetry::Accumulate(Telemetry::FORGET_SKIPPABLE_MAX,
sMaxForgetSkippableTime / PR_USEC_PER_MSEC);
PRTime delta = GetCollectionTimeDelta();
uint32_t cleanups = sForgetSkippableBeforeCC ? sForgetSkippableBeforeCC : 1;
uint32_t minForgetSkippableTime = (sMinForgetSkippableTime == UINT32_MAX)
? 0 : sMinForgetSkippableTime;
if (sPostGCEventsToConsole) {
nsCString mergeMsg;
if (aResults.mMergedZones) {
mergeMsg.AssignLiteral(" merged");
}
nsCString gcMsg;
if (aResults.mForcedGC) {
gcMsg.AssignLiteral(", forced a GC");
}
NS_NAMED_MULTILINE_LITERAL_STRING(kFmt,
MOZ_UTF16("CC(T+%.1f) max pause: %lums, total time: %lums, slices: %lu, suspected: %lu, visited: %lu RCed and %lu%s GCed, collected: %lu RCed and %lu GCed (%lu|%lu|%lu waiting for GC)%s\n")
MOZ_UTF16("ForgetSkippable %lu times before CC, min: %lu ms, max: %lu ms, avg: %lu ms, total: %lu ms, max sync: %lu ms, removed: %lu"));
nsString msg;
msg.Adopt(nsTextFormatter::smprintf(kFmt.get(), double(delta) / PR_USEC_PER_SEC,
gCCStats.mMaxSliceTime, gCCStats.mTotalSliceTime,
aResults.mNumSlices, gCCStats.mSuspected,
aResults.mVisitedRefCounted, aResults.mVisitedGCed, mergeMsg.get(),
aResults.mFreedRefCounted, aResults.mFreedGCed,
sCCollectedWaitingForGC, sCCollectedZonesWaitingForGC, sLikelyShortLivingObjectsNeedingGC,
gcMsg.get(),
sForgetSkippableBeforeCC,
minForgetSkippableTime / PR_USEC_PER_MSEC,
sMaxForgetSkippableTime / PR_USEC_PER_MSEC,
(sTotalForgetSkippableTime / cleanups) /
PR_USEC_PER_MSEC,
sTotalForgetSkippableTime / PR_USEC_PER_MSEC,
gCCStats.mMaxSkippableDuration, sRemovedPurples));
nsCOMPtr<nsIConsoleService> cs =
do_GetService(NS_CONSOLESERVICE_CONTRACTID);
if (cs) {
cs->LogStringMessage(msg.get());
}
}
if (sPostGCEventsToObserver) {
NS_NAMED_MULTILINE_LITERAL_STRING(kJSONFmt,
MOZ_UTF16("{ \"timestamp\": %llu, ")
MOZ_UTF16("\"duration\": %lu, ")
MOZ_UTF16("\"max_slice_pause\": %lu, ")
MOZ_UTF16("\"total_slice_pause\": %lu, ")
MOZ_UTF16("\"max_finish_gc_duration\": %lu, ")
MOZ_UTF16("\"max_sync_skippable_duration\": %lu, ")
MOZ_UTF16("\"suspected\": %lu, ")
MOZ_UTF16("\"visited\": { ")
MOZ_UTF16("\"RCed\": %lu, ")
MOZ_UTF16("\"GCed\": %lu }, ")
MOZ_UTF16("\"collected\": { ")
MOZ_UTF16("\"RCed\": %lu, ")
MOZ_UTF16("\"GCed\": %lu }, ")
MOZ_UTF16("\"waiting_for_gc\": %lu, ")
MOZ_UTF16("\"zones_waiting_for_gc\": %lu, ")
MOZ_UTF16("\"short_living_objects_waiting_for_gc\": %lu, ")
MOZ_UTF16("\"forced_gc\": %d, ")
MOZ_UTF16("\"forget_skippable\": { ")
MOZ_UTF16("\"times_before_cc\": %lu, ")
MOZ_UTF16("\"min\": %lu, ")
MOZ_UTF16("\"max\": %lu, ")
MOZ_UTF16("\"avg\": %lu, ")
MOZ_UTF16("\"total\": %lu, ")
MOZ_UTF16("\"removed\": %lu } ")
MOZ_UTF16("}"));
nsString json;
json.Adopt(nsTextFormatter::smprintf(kJSONFmt.get(), endCCTime, ccNowDuration,
gCCStats.mMaxSliceTime,
gCCStats.mTotalSliceTime,
gCCStats.mMaxGCDuration,
gCCStats.mMaxSkippableDuration,
gCCStats.mSuspected,
aResults.mVisitedRefCounted, aResults.mVisitedGCed,
aResults.mFreedRefCounted, aResults.mFreedGCed,
sCCollectedWaitingForGC,
sCCollectedZonesWaitingForGC,
sLikelyShortLivingObjectsNeedingGC,
aResults.mForcedGC,
sForgetSkippableBeforeCC,
minForgetSkippableTime / PR_USEC_PER_MSEC,
sMaxForgetSkippableTime / PR_USEC_PER_MSEC,
(sTotalForgetSkippableTime / cleanups) /
PR_USEC_PER_MSEC,
sTotalForgetSkippableTime / PR_USEC_PER_MSEC,
sRemovedPurples));
nsCOMPtr<nsIObserverService> observerService = mozilla::services::GetObserverService();
if (observerService) {
observerService->NotifyObservers(nullptr, "cycle-collection-statistics", json.get());
}
}
// Update global state to indicate we have just run a cycle collection.
sMinForgetSkippableTime = UINT32_MAX;
sMaxForgetSkippableTime = 0;
sTotalForgetSkippableTime = 0;
sRemovedPurples = 0;
sForgetSkippableBeforeCC = 0;
sNeedsFullCC = false;
sNeedsGCAfterCC = false;
gCCStats.Clear();
}
// static
void
InterSliceGCTimerFired(nsITimer *aTimer, void *aClosure)
{
nsJSContext::KillInterSliceGCTimer();
nsJSContext::GarbageCollectNow(JS::gcreason::INTER_SLICE_GC,
nsJSContext::IncrementalGC,
nsJSContext::NonShrinkingGC,
NS_INTERSLICE_GC_BUDGET);
}
// static
void
GCTimerFired(nsITimer *aTimer, void *aClosure)
{
nsJSContext::KillGCTimer();
uintptr_t reason = reinterpret_cast<uintptr_t>(aClosure);
nsJSContext::GarbageCollectNow(static_cast<JS::gcreason::Reason>(reason),
nsJSContext::IncrementalGC);
}
void
ShrinkGCBuffersTimerFired(nsITimer *aTimer, void *aClosure)
{
nsJSContext::KillShrinkGCBuffersTimer();
nsJSContext::ShrinkGCBuffersNow();
}
static bool
ShouldTriggerCC(uint32_t aSuspected)
{
return sNeedsFullCC ||
aSuspected > NS_CC_PURPLE_LIMIT ||
(aSuspected > NS_CC_FORCED_PURPLE_LIMIT &&
TimeUntilNow(sLastCCEndTime) > NS_CC_FORCED);
}
static void
CCTimerFired(nsITimer *aTimer, void *aClosure)
{
if (sDidShutdown) {
return;
}
static uint32_t ccDelay = NS_CC_DELAY;
if (sCCLockedOut) {
ccDelay = NS_CC_DELAY / 3;
PRTime now = PR_Now();
if (sCCLockedOutTime == 0) {
// Reset sCCTimerFireCount so that we run forgetSkippable
// often enough before CC. Because of reduced ccDelay
// forgetSkippable will be called just a few times.
// NS_MAX_CC_LOCKEDOUT_TIME limit guarantees that we end up calling
// forgetSkippable and CycleCollectNow eventually.
sCCTimerFireCount = 0;
sCCLockedOutTime = now;
return;
}
if (now - sCCLockedOutTime < NS_MAX_CC_LOCKEDOUT_TIME) {
return;
}
}
++sCCTimerFireCount;
// During early timer fires, we only run forgetSkippable. During the first
// late timer fire, we decide if we are going to have a second and final
// late timer fire, where we may begin to run the CC. Should run at least one
// early timer fire to allow cleanup before the CC.
int32_t numEarlyTimerFires = std::max((int32_t)ccDelay / NS_CC_SKIPPABLE_DELAY - 2, 1);
bool isLateTimerFire = sCCTimerFireCount > numEarlyTimerFires;
uint32_t suspected = nsCycleCollector_suspectedCount();
if (isLateTimerFire && ShouldTriggerCC(suspected)) {
if (sCCTimerFireCount == numEarlyTimerFires + 1) {
FireForgetSkippable(suspected, true);
if (ShouldTriggerCC(nsCycleCollector_suspectedCount())) {
// Our efforts to avoid a CC have failed, so we return to let the
// timer fire once more to trigger a CC.
return;
}
} else {
// We are in the final timer fire and still meet the conditions for
// triggering a CC. Let RunCycleCollectorSlice finish the current IGC, if
// any because that will allow us to include the GC time in the CC pause.
nsJSContext::RunCycleCollectorSlice();
}
} else if (((sPreviousSuspectedCount + 100) <= suspected) ||
(sCleanupsSinceLastGC < NS_MAJOR_FORGET_SKIPPABLE_CALLS)) {
// Only do a forget skippable if there are more than a few new objects
// or we're doing the initial forget skippables.
FireForgetSkippable(suspected, false);
}
if (isLateTimerFire) {
ccDelay = NS_CC_DELAY;
// We have either just run the CC or decided we don't want to run the CC
// next time, so kill the timer.
sPreviousSuspectedCount = 0;
nsJSContext::KillCCTimer();
}
}
// static
uint32_t
nsJSContext::CleanupsSinceLastGC()
{
return sCleanupsSinceLastGC;
}
// static
void
nsJSContext::LoadStart()
{
sLoadingInProgress = true;
++sPendingLoadCount;
}
// static
void
nsJSContext::LoadEnd()
{
if (!sLoadingInProgress)
return;
// sPendingLoadCount is not a well managed load counter (and doesn't
// need to be), so make sure we don't make it wrap backwards here.
if (sPendingLoadCount > 0) {
--sPendingLoadCount;
return;
}
// Its probably a good idea to GC soon since we have finished loading.
sLoadingInProgress = false;
PokeGC(JS::gcreason::LOAD_END);
}
// Only trigger expensive timers when they have been checked a number of times.
static bool
ReadyToTriggerExpensiveCollectorTimer()
{
bool ready = kPokesBetweenExpensiveCollectorTriggers < ++sExpensiveCollectorPokes;
if (ready) {
sExpensiveCollectorPokes = 0;
}
return ready;
}
// Check all of the various collector timers and see if they are waiting to fire.
// For the synchronous collector timers, sGCTimer and sCCTimer, we only want to trigger
// the collection occasionally, because they are expensive. The incremental collector
// timers, sInterSliceGCTimer and sICCTimer, are fast and need to be run many times, so
// always run their corresponding timer.
// This does not check sFullGCTimer, as that's an even more expensive collection we run
// on a long timer.
// static
void
nsJSContext::RunNextCollectorTimer()
{
if (sShuttingDown) {
return;
}
if (sGCTimer) {
if (ReadyToTriggerExpensiveCollectorTimer()) {
GCTimerFired(nullptr, reinterpret_cast<void *>(JS::gcreason::DOM_WINDOW_UTILS));
}
return;
}
if (sInterSliceGCTimer) {
InterSliceGCTimerFired(nullptr, nullptr);
return;
}
// Check the CC timers after the GC timers, because the CC timers won't do
// anything if a GC is in progress.
MOZ_ASSERT(!sCCLockedOut, "Don't check the CC timers if the CC is locked out.");
if (sCCTimer) {
if (ReadyToTriggerExpensiveCollectorTimer()) {
CCTimerFired(nullptr, nullptr);
}
return;
}
if (sICCTimer) {
ICCTimerFired(nullptr, nullptr);
return;
}
}
// static
void
nsJSContext::PokeGC(JS::gcreason::Reason aReason, int aDelay)
{
if (sGCTimer || sInterSliceGCTimer || sShuttingDown) {
// There's already a timer for GC'ing, just return
return;
}
if (sCCTimer) {
// Make sure CC is called...
sNeedsFullCC = true;
// and GC after it.
sNeedsGCAfterCC = true;
return;
}
if (sICCTimer) {
// Make sure GC is called after the current CC completes.
// No need to set sNeedsFullCC because we are currently running a CC.
sNeedsGCAfterCC = true;
return;
}
CallCreateInstance("@mozilla.org/timer;1", &sGCTimer);
if (!sGCTimer) {
// Failed to create timer (probably because we're in XPCOM shutdown)
return;
}
static bool first = true;
sGCTimer->InitWithFuncCallback(GCTimerFired, reinterpret_cast<void *>(aReason),
aDelay
? aDelay
: (first
? NS_FIRST_GC_DELAY
: NS_GC_DELAY),
nsITimer::TYPE_ONE_SHOT);
first = false;
}
// static
void
nsJSContext::PokeShrinkGCBuffers()
{
if (sShrinkGCBuffersTimer || sShuttingDown) {
return;
}
CallCreateInstance("@mozilla.org/timer;1", &sShrinkGCBuffersTimer);
if (!sShrinkGCBuffersTimer) {
// Failed to create timer (probably because we're in XPCOM shutdown)
return;
}
sShrinkGCBuffersTimer->InitWithFuncCallback(ShrinkGCBuffersTimerFired, nullptr,
NS_SHRINK_GC_BUFFERS_DELAY,
nsITimer::TYPE_ONE_SHOT);
}
// static
void
nsJSContext::MaybePokeCC()
{
if (sCCTimer || sICCTimer || sShuttingDown || !sHasRunGC) {
return;
}
if (ShouldTriggerCC(nsCycleCollector_suspectedCount())) {
sCCTimerFireCount = 0;
CallCreateInstance("@mozilla.org/timer;1", &sCCTimer);
if (!sCCTimer) {
return;
}
// We can kill some objects before running forgetSkippable.
nsCycleCollector_dispatchDeferredDeletion();
sCCTimer->InitWithFuncCallback(CCTimerFired, nullptr,
NS_CC_SKIPPABLE_DELAY,
nsITimer::TYPE_REPEATING_SLACK);
}
}
//static
void
nsJSContext::KillGCTimer()
{
if (sGCTimer) {
sGCTimer->Cancel();
NS_RELEASE(sGCTimer);
}
}
void
nsJSContext::KillFullGCTimer()
{
if (sFullGCTimer) {
sFullGCTimer->Cancel();
NS_RELEASE(sFullGCTimer);
}
}
void
nsJSContext::KillInterSliceGCTimer()
{
if (sInterSliceGCTimer) {
sInterSliceGCTimer->Cancel();
NS_RELEASE(sInterSliceGCTimer);
}
}
//static
void
nsJSContext::KillShrinkGCBuffersTimer()
{
if (sShrinkGCBuffersTimer) {
sShrinkGCBuffersTimer->Cancel();
NS_RELEASE(sShrinkGCBuffersTimer);
}
}
//static
void
nsJSContext::KillCCTimer()
{
sCCLockedOutTime = 0;
if (sCCTimer) {
sCCTimer->Cancel();
NS_RELEASE(sCCTimer);
}
}
//static
void
nsJSContext::KillICCTimer()
{
sCCLockedOutTime = 0;
if (sICCTimer) {
sICCTimer->Cancel();
NS_RELEASE(sICCTimer);
}
}
class NotifyGCEndRunnable : public nsRunnable
{
nsString mMessage;
public:
explicit NotifyGCEndRunnable(const nsString& aMessage) : mMessage(aMessage) {}
NS_DECL_NSIRUNNABLE
};
NS_IMETHODIMP
NotifyGCEndRunnable::Run()
{
MOZ_ASSERT(NS_IsMainThread());
nsCOMPtr<nsIObserverService> observerService = mozilla::services::GetObserverService();
if (!observerService) {
return NS_OK;
}
const char16_t oomMsg[3] = { '{', '}', 0 };
const char16_t *toSend = mMessage.get() ? mMessage.get() : oomMsg;
observerService->NotifyObservers(nullptr, "garbage-collection-statistics", toSend);
return NS_OK;
}
static void
DOMGCSliceCallback(JSRuntime *aRt, JS::GCProgress aProgress, const JS::GCDescription &aDesc)
{
NS_ASSERTION(NS_IsMainThread(), "GCs must run on the main thread");
switch (aProgress) {
case JS::GC_CYCLE_BEGIN: {
// Prevent cycle collections and shrinking during incremental GC.
sCCLockedOut = true;
nsJSContext::KillShrinkGCBuffersTimer();
break;
}
case JS::GC_CYCLE_END: {
PRTime delta = GetCollectionTimeDelta();
if (sPostGCEventsToConsole) {
NS_NAMED_LITERAL_STRING(kFmt, "GC(T+%.1f) ");
nsString prefix, gcstats;
gcstats.Adopt(aDesc.formatMessage(aRt));
prefix.Adopt(nsTextFormatter::smprintf(kFmt.get(),
double(delta) / PR_USEC_PER_SEC));
nsString msg = prefix + gcstats;
nsCOMPtr<nsIConsoleService> cs = do_GetService(NS_CONSOLESERVICE_CONTRACTID);
if (cs) {
cs->LogStringMessage(msg.get());
}
}
if (sPostGCEventsToObserver) {
nsString json;
json.Adopt(aDesc.formatJSON(aRt, PR_Now()));
nsRefPtr<NotifyGCEndRunnable> notify = new NotifyGCEndRunnable(json);
NS_DispatchToMainThread(notify);
}
sCCLockedOut = false;
// May need to kill the inter-slice GC timer
nsJSContext::KillInterSliceGCTimer();
sCCollectedWaitingForGC = 0;
sCCollectedZonesWaitingForGC = 0;
sLikelyShortLivingObjectsNeedingGC = 0;
sCleanupsSinceLastGC = 0;
sNeedsFullCC = true;
sHasRunGC = true;
nsJSContext::MaybePokeCC();
if (aDesc.isCompartment_) {
if (!sFullGCTimer && !sShuttingDown) {
CallCreateInstance("@mozilla.org/timer;1", &sFullGCTimer);
sFullGCTimer->InitWithFuncCallback(FullGCTimerFired,
nullptr,
NS_FULL_GC_DELAY,
nsITimer::TYPE_ONE_SHOT);
}
} else {
nsJSContext::KillFullGCTimer();
// Avoid shrinking during heavy activity, which is suggested by
// compartment GC. We don't need to shrink after a shrinking GC as this
// happens automatically in this case.
if (aDesc.invocationKind_ == GC_NORMAL) {
nsJSContext::PokeShrinkGCBuffers();
}
}
if (ShouldTriggerCC(nsCycleCollector_suspectedCount())) {
nsCycleCollector_dispatchDeferredDeletion();
}
break;
}
case JS::GC_SLICE_BEGIN:
break;
case JS::GC_SLICE_END:
// The GC has more work to do, so schedule another GC slice.
nsJSContext::KillInterSliceGCTimer();
if (!sShuttingDown) {
CallCreateInstance("@mozilla.org/timer;1", &sInterSliceGCTimer);
sInterSliceGCTimer->InitWithFuncCallback(InterSliceGCTimerFired,
nullptr,
NS_INTERSLICE_GC_DELAY,
nsITimer::TYPE_ONE_SHOT);
}
if (ShouldTriggerCC(nsCycleCollector_suspectedCount())) {
nsCycleCollector_dispatchDeferredDeletion();
}
break;
default:
MOZ_CRASH("Unexpected GCProgress value");
}
if (sPrevGCSliceCallback) {
(*sPrevGCSliceCallback)(aRt, aProgress, aDesc);
}
}
void
nsJSContext::SetWindowProxy(JS::Handle<JSObject*> aWindowProxy)
{
mWindowProxy = aWindowProxy;
}
JSObject*
nsJSContext::GetWindowProxy()
{
JSObject* windowProxy = GetWindowProxyPreserveColor();
if (windowProxy) {
JS::ExposeObjectToActiveJS(windowProxy);
}
return windowProxy;
}
JSObject*
nsJSContext::GetWindowProxyPreserveColor()
{
return mWindowProxy;
}
void
nsJSContext::LikelyShortLivingObjectCreated()
{
++sLikelyShortLivingObjectsNeedingGC;
}
void
mozilla::dom::StartupJSEnvironment()
{
// initialize all our statics, so that we can restart XPCOM
sGCTimer = sFullGCTimer = sCCTimer = sICCTimer = nullptr;
sCCLockedOut = false;
sCCLockedOutTime = 0;
sLastCCEndTime = TimeStamp();
sHasRunGC = false;
sPendingLoadCount = 0;
sLoadingInProgress = false;
sCCollectedWaitingForGC = 0;
sCCollectedZonesWaitingForGC = 0;
sLikelyShortLivingObjectsNeedingGC = 0;
sPostGCEventsToConsole = false;
sNeedsFullCC = false;
sNeedsGCAfterCC = false;
gNameSpaceManager = nullptr;
sRuntimeService = nullptr;
sRuntime = nullptr;
sIsInitialized = false;
sDidShutdown = false;
sShuttingDown = false;
sContextCount = 0;
sSecurityManager = nullptr;
gCCStats.Init();
sExpensiveCollectorPokes = 0;
}
static void
ReportAllJSExceptionsPrefChangedCallback(const char* aPrefName, void* aClosure)
{
bool reportAll = Preferences::GetBool(aPrefName, false);
nsContentUtils::XPConnect()->SetReportAllJSExceptions(reportAll);
}
static void
SetMemoryHighWaterMarkPrefChangedCallback(const char* aPrefName, void* aClosure)
{
int32_t highwatermark = Preferences::GetInt(aPrefName, 128);
JS_SetGCParameter(sRuntime, JSGC_MAX_MALLOC_BYTES,
highwatermark * 1024L * 1024L);
}
static void
SetMemoryMaxPrefChangedCallback(const char* aPrefName, void* aClosure)
{
int32_t pref = Preferences::GetInt(aPrefName, -1);
// handle overflow and negative pref values
uint32_t max = (pref <= 0 || pref >= 0x1000) ? -1 : (uint32_t)pref * 1024 * 1024;
JS_SetGCParameter(sRuntime, JSGC_MAX_BYTES, max);
}
static void
SetMemoryGCModePrefChangedCallback(const char* aPrefName, void* aClosure)
{
bool enableCompartmentGC = Preferences::GetBool("javascript.options.mem.gc_per_compartment");
bool enableIncrementalGC = Preferences::GetBool("javascript.options.mem.gc_incremental");
JSGCMode mode;
if (enableIncrementalGC) {
mode = JSGC_MODE_INCREMENTAL;
} else if (enableCompartmentGC) {
mode = JSGC_MODE_COMPARTMENT;
} else {
mode = JSGC_MODE_GLOBAL;
}
JS_SetGCParameter(sRuntime, JSGC_MODE, mode);
}
static void
SetMemoryGCSliceTimePrefChangedCallback(const char* aPrefName, void* aClosure)
{
int32_t pref = Preferences::GetInt(aPrefName, -1);
// handle overflow and negative pref values
if (pref > 0 && pref < 100000)
JS_SetGCParameter(sRuntime, JSGC_SLICE_TIME_BUDGET, pref);
}
static void
SetMemoryGCCompactingPrefChangedCallback(const char* aPrefName, void* aClosure)
{
bool pref = Preferences::GetBool(aPrefName);
JS_SetGCParameter(sRuntime, JSGC_COMPACTING_ENABLED, pref);
}
static void
SetMemoryGCPrefChangedCallback(const char* aPrefName, void* aClosure)
{
int32_t pref = Preferences::GetInt(aPrefName, -1);
// handle overflow and negative pref values
if (pref >= 0 && pref < 10000)
JS_SetGCParameter(sRuntime, (JSGCParamKey)(intptr_t)aClosure, pref);
}
static void
SetMemoryGCDynamicHeapGrowthPrefChangedCallback(const char* aPrefName, void* aClosure)
{
bool pref = Preferences::GetBool(aPrefName);
JS_SetGCParameter(sRuntime, JSGC_DYNAMIC_HEAP_GROWTH, pref);
}
static void
SetMemoryGCDynamicMarkSlicePrefChangedCallback(const char* aPrefName, void* aClosure)
{
bool pref = Preferences::GetBool(aPrefName);
JS_SetGCParameter(sRuntime, JSGC_DYNAMIC_MARK_SLICE, pref);
}
static void
SetIncrementalCCPrefChangedCallback(const char* aPrefName, void* aClosure)
{
bool pref = Preferences::GetBool(aPrefName);
sIncrementalCC = pref;
}
JSObject*
NS_DOMReadStructuredClone(JSContext* cx,
JSStructuredCloneReader* reader,
uint32_t tag,
uint32_t data,
void* closure)
{
if (tag == SCTAG_DOM_IMAGEDATA) {
return ReadStructuredCloneImageData(cx, reader);
} else if (tag == SCTAG_DOM_WEBCRYPTO_KEY) {
nsIGlobalObject *global = xpc::NativeGlobal(JS::CurrentGlobalOrNull(cx));
if (!global) {
return nullptr;
}
// Prevent the return value from being trashed by a GC during ~nsRefPtr.
JS::Rooted<JSObject*> result(cx);
{
nsRefPtr<CryptoKey> key = new CryptoKey(global);
if (!key->ReadStructuredClone(reader)) {
result = nullptr;
} else {
result = key->WrapObject(cx);
}
}
return result;
} else if (tag == SCTAG_DOM_NULL_PRINCIPAL ||
tag == SCTAG_DOM_SYSTEM_PRINCIPAL ||
tag == SCTAG_DOM_CONTENT_PRINCIPAL) {
mozilla::ipc::PrincipalInfo info;
if (tag == SCTAG_DOM_SYSTEM_PRINCIPAL) {
info = mozilla::ipc::SystemPrincipalInfo();
} else if (tag == SCTAG_DOM_NULL_PRINCIPAL) {
info = mozilla::ipc::NullPrincipalInfo();
} else {
uint32_t appId = data;
uint32_t isInBrowserElement, specLength;
if (!JS_ReadUint32Pair(reader, &isInBrowserElement, &specLength)) {
return nullptr;
}
nsAutoCString spec;
spec.SetLength(specLength);
if (!JS_ReadBytes(reader, spec.BeginWriting(), specLength)) {
return nullptr;
}
info = mozilla::ipc::ContentPrincipalInfo(appId, isInBrowserElement, spec);
}
nsresult rv;
nsCOMPtr<nsIPrincipal> principal = PrincipalInfoToPrincipal(info, &rv);
if (NS_WARN_IF(NS_FAILED(rv))) {
xpc::Throw(cx, NS_ERROR_DOM_DATA_CLONE_ERR);
return nullptr;
}
JS::RootedValue result(cx);
rv = nsContentUtils::WrapNative(cx, principal, &NS_GET_IID(nsIPrincipal), &result);
if (NS_FAILED(rv)) {
xpc::Throw(cx, NS_ERROR_DOM_DATA_CLONE_ERR);
return nullptr;
}
return result.toObjectOrNull();
}
// Don't know what this is. Bail.
xpc::Throw(cx, NS_ERROR_DOM_DATA_CLONE_ERR);
return nullptr;
}
bool
NS_DOMWriteStructuredClone(JSContext* cx,
JSStructuredCloneWriter* writer,
JS::Handle<JSObject*> obj,
void *closure)
{
// Handle ImageData cloning
ImageData* imageData;
if (NS_SUCCEEDED(UNWRAP_OBJECT(ImageData, obj, imageData))) {
return WriteStructuredCloneImageData(cx, writer, imageData);
}
// Handle Key cloning
CryptoKey* key;
if (NS_SUCCEEDED(UNWRAP_OBJECT(CryptoKey, obj, key))) {
return JS_WriteUint32Pair(writer, SCTAG_DOM_WEBCRYPTO_KEY, 0) &&
key->WriteStructuredClone(writer);
}
if (xpc::IsReflector(obj)) {
nsCOMPtr<nsISupports> base = xpc::UnwrapReflectorToISupports(obj);
nsCOMPtr<nsIPrincipal> principal = do_QueryInterface(base);
if (principal) {
mozilla::ipc::PrincipalInfo info;
if (NS_WARN_IF(NS_FAILED(PrincipalToPrincipalInfo(principal, &info)))) {
xpc::Throw(cx, NS_ERROR_DOM_DATA_CLONE_ERR);
return false;
}
if (info.type() == mozilla::ipc::PrincipalInfo::TNullPrincipalInfo) {
return JS_WriteUint32Pair(writer, SCTAG_DOM_NULL_PRINCIPAL, 0);
}
if (info.type() == mozilla::ipc::PrincipalInfo::TSystemPrincipalInfo) {
return JS_WriteUint32Pair(writer, SCTAG_DOM_SYSTEM_PRINCIPAL, 0);
}
MOZ_ASSERT(info.type() == mozilla::ipc::PrincipalInfo::TContentPrincipalInfo);
const mozilla::ipc::ContentPrincipalInfo& cInfo = info;
return JS_WriteUint32Pair(writer, SCTAG_DOM_CONTENT_PRINCIPAL, cInfo.appId()) &&
JS_WriteUint32Pair(writer, cInfo.isInBrowserElement(), cInfo.spec().Length()) &&
JS_WriteBytes(writer, cInfo.spec().get(), cInfo.spec().Length());
}
}
// Don't know what this is
xpc::Throw(cx, NS_ERROR_DOM_DATA_CLONE_ERR);
return false;
}
void
NS_DOMStructuredCloneError(JSContext* cx,
uint32_t errorid)
{
// We don't currently support any extensions to structured cloning.
xpc::Throw(cx, NS_ERROR_DOM_DATA_CLONE_ERR);
}
static bool
AsmJSCacheOpenEntryForRead(JS::Handle<JSObject*> aGlobal,
const char16_t* aBegin,
const char16_t* aLimit,
size_t* aSize,
const uint8_t** aMemory,
intptr_t *aHandle)
{
nsIPrincipal* principal =
nsJSPrincipals::get(JS_GetCompartmentPrincipals(js::GetObjectCompartment(aGlobal)));
return asmjscache::OpenEntryForRead(principal, aBegin, aLimit, aSize, aMemory,
aHandle);
}
static JS::AsmJSCacheResult
AsmJSCacheOpenEntryForWrite(JS::Handle<JSObject*> aGlobal,
bool aInstalled,
const char16_t* aBegin,
const char16_t* aEnd,
size_t aSize,
uint8_t** aMemory,
intptr_t* aHandle)
{
nsIPrincipal* principal =
nsJSPrincipals::get(JS_GetCompartmentPrincipals(js::GetObjectCompartment(aGlobal)));
return asmjscache::OpenEntryForWrite(principal, aInstalled, aBegin, aEnd,
aSize, aMemory, aHandle);
}
static NS_DEFINE_CID(kDOMScriptObjectFactoryCID, NS_DOM_SCRIPT_OBJECT_FACTORY_CID);
void
nsJSContext::EnsureStatics()
{
if (sIsInitialized) {
if (!nsContentUtils::XPConnect()) {
MOZ_CRASH();
}
return;
}
nsresult rv = CallGetService(NS_SCRIPTSECURITYMANAGER_CONTRACTID,
&sSecurityManager);
if (NS_FAILED(rv)) {
MOZ_CRASH();
}
rv = CallGetService(kJSRuntimeServiceContractID, &sRuntimeService);
if (NS_FAILED(rv)) {
MOZ_CRASH();
}
rv = sRuntimeService->GetRuntime(&sRuntime);
if (NS_FAILED(rv)) {
MOZ_CRASH();
}
// Let's make sure that our main thread is the same as the xpcom main thread.
MOZ_ASSERT(NS_IsMainThread());
sPrevGCSliceCallback = JS::SetGCSliceCallback(sRuntime, DOMGCSliceCallback);
// Set up the structured clone callbacks.
static const JSStructuredCloneCallbacks cloneCallbacks = {
NS_DOMReadStructuredClone,
NS_DOMWriteStructuredClone,
NS_DOMStructuredCloneError,
nullptr,
nullptr,
nullptr
};
JS_SetStructuredCloneCallbacks(sRuntime, &cloneCallbacks);
// Set up the asm.js cache callbacks
static const JS::AsmJSCacheOps asmJSCacheOps = {
AsmJSCacheOpenEntryForRead,
asmjscache::CloseEntryForRead,
AsmJSCacheOpenEntryForWrite,
asmjscache::CloseEntryForWrite,
asmjscache::GetBuildId
};
JS::SetAsmJSCacheOps(sRuntime, &asmJSCacheOps);
// Set these global xpconnect options...
Preferences::RegisterCallbackAndCall(ReportAllJSExceptionsPrefChangedCallback,
"dom.report_all_js_exceptions");
Preferences::RegisterCallbackAndCall(SetMemoryHighWaterMarkPrefChangedCallback,
"javascript.options.mem.high_water_mark");
Preferences::RegisterCallbackAndCall(SetMemoryMaxPrefChangedCallback,
"javascript.options.mem.max");
Preferences::RegisterCallbackAndCall(SetMemoryGCModePrefChangedCallback,
"javascript.options.mem.gc_per_compartment");
Preferences::RegisterCallbackAndCall(SetMemoryGCModePrefChangedCallback,
"javascript.options.mem.gc_incremental");
Preferences::RegisterCallbackAndCall(SetMemoryGCSliceTimePrefChangedCallback,
"javascript.options.mem.gc_incremental_slice_ms");
Preferences::RegisterCallbackAndCall(SetMemoryGCCompactingPrefChangedCallback,
"javascript.options.mem.gc_compacting");
Preferences::RegisterCallbackAndCall(SetMemoryGCPrefChangedCallback,
"javascript.options.mem.gc_high_frequency_time_limit_ms",
(void *)JSGC_HIGH_FREQUENCY_TIME_LIMIT);
Preferences::RegisterCallbackAndCall(SetMemoryGCDynamicMarkSlicePrefChangedCallback,
"javascript.options.mem.gc_dynamic_mark_slice");
Preferences::RegisterCallbackAndCall(SetMemoryGCDynamicHeapGrowthPrefChangedCallback,
"javascript.options.mem.gc_dynamic_heap_growth");
Preferences::RegisterCallbackAndCall(SetMemoryGCPrefChangedCallback,
"javascript.options.mem.gc_low_frequency_heap_growth",
(void *)JSGC_LOW_FREQUENCY_HEAP_GROWTH);
Preferences::RegisterCallbackAndCall(SetMemoryGCPrefChangedCallback,
"javascript.options.mem.gc_high_frequency_heap_growth_min",
(void *)JSGC_HIGH_FREQUENCY_HEAP_GROWTH_MIN);
Preferences::RegisterCallbackAndCall(SetMemoryGCPrefChangedCallback,
"javascript.options.mem.gc_high_frequency_heap_growth_max",
(void *)JSGC_HIGH_FREQUENCY_HEAP_GROWTH_MAX);
Preferences::RegisterCallbackAndCall(SetMemoryGCPrefChangedCallback,
"javascript.options.mem.gc_high_frequency_low_limit_mb",
(void *)JSGC_HIGH_FREQUENCY_LOW_LIMIT);
Preferences::RegisterCallbackAndCall(SetMemoryGCPrefChangedCallback,
"javascript.options.mem.gc_high_frequency_high_limit_mb",
(void *)JSGC_HIGH_FREQUENCY_HIGH_LIMIT);
Preferences::RegisterCallbackAndCall(SetMemoryGCPrefChangedCallback,
"javascript.options.mem.gc_allocation_threshold_mb",
(void *)JSGC_ALLOCATION_THRESHOLD);
Preferences::RegisterCallbackAndCall(SetMemoryGCPrefChangedCallback,
"javascript.options.mem.gc_decommit_threshold_mb",
(void *)JSGC_DECOMMIT_THRESHOLD);
Preferences::RegisterCallbackAndCall(SetIncrementalCCPrefChangedCallback,
"dom.cycle_collector.incremental");
Preferences::RegisterCallbackAndCall(SetMemoryGCPrefChangedCallback,
"javascript.options.mem.gc_min_empty_chunk_count",
(void *)JSGC_MIN_EMPTY_CHUNK_COUNT);
Preferences::RegisterCallbackAndCall(SetMemoryGCPrefChangedCallback,
"javascript.options.mem.gc_max_empty_chunk_count",
(void *)JSGC_MAX_EMPTY_CHUNK_COUNT);
nsCOMPtr<nsIObserverService> obs = mozilla::services::GetObserverService();
if (!obs) {
MOZ_CRASH();
}
Preferences::AddBoolVarCache(&sGCOnMemoryPressure,
"javascript.options.gc_on_memory_pressure",
true);
nsIObserver* observer = new nsJSEnvironmentObserver();
obs->AddObserver(observer, "memory-pressure", false);
obs->AddObserver(observer, "quit-application", false);
obs->AddObserver(observer, NS_XPCOM_SHUTDOWN_OBSERVER_ID, false);
// Bug 907848 - We need to explicitly get the nsIDOMScriptObjectFactory
// service in order to force its constructor to run, which registers a
// shutdown observer. It would be nice to make this more explicit and less
// side-effect-y.
nsCOMPtr<nsIDOMScriptObjectFactory> factory = do_GetService(kDOMScriptObjectFactoryCID);
if (!factory) {
MOZ_CRASH();
}
sIsInitialized = true;
}
void
nsJSContext::NotifyDidPaint()
{
sDidPaintAfterPreviousICCSlice = true;
}
nsScriptNameSpaceManager*
mozilla::dom::GetNameSpaceManager()
{
if (sDidShutdown)
return nullptr;
if (!gNameSpaceManager) {
gNameSpaceManager = new nsScriptNameSpaceManager;
NS_ADDREF(gNameSpaceManager);
nsresult rv = gNameSpaceManager->Init();
NS_ENSURE_SUCCESS(rv, nullptr);
}
return gNameSpaceManager;
}
void
mozilla::dom::ShutdownJSEnvironment()
{
KillTimers();
NS_IF_RELEASE(gNameSpaceManager);
if (!sContextCount) {
// We're being shutdown, and there are no more contexts
// alive, release the JS runtime service and the security manager.
NS_IF_RELEASE(sRuntimeService);
NS_IF_RELEASE(sSecurityManager);
}
sShuttingDown = true;
sDidShutdown = true;
}
// A fast-array class for JS. This class supports both nsIJSScriptArray and
// nsIArray. If it is JS itself providing and consuming this class, all work
// can be done via nsIJSScriptArray, and avoid the conversion of elements
// to/from nsISupports.
// When consumed by non-JS (eg, another script language), conversion is done
// on-the-fly.
class nsJSArgArray final : public nsIJSArgArray {
public:
nsJSArgArray(JSContext *aContext, uint32_t argc, JS::Value *argv,
nsresult *prv);
// nsISupports
NS_DECL_CYCLE_COLLECTING_ISUPPORTS
NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS_AMBIGUOUS(nsJSArgArray,
nsIJSArgArray)
// nsIArray
NS_DECL_NSIARRAY
// nsIJSArgArray
nsresult GetArgs(uint32_t* argc, void** argv) override;
void ReleaseJSObjects();
protected:
~nsJSArgArray();
JSContext *mContext;
JS::Heap<JS::Value> *mArgv;
uint32_t mArgc;
};
nsJSArgArray::nsJSArgArray(JSContext *aContext, uint32_t argc, JS::Value *argv,
nsresult *prv) :
mContext(aContext),
mArgv(nullptr),
mArgc(argc)
{
// copy the array - we don't know its lifetime, and ours is tied to xpcom
// refcounting.
if (argc) {
mArgv = new (fallible) JS::Heap<JS::Value>[argc];
if (!mArgv) {
*prv = NS_ERROR_OUT_OF_MEMORY;
return;
}
}
// Callers are allowed to pass in a null argv even for argc > 0. They can
// then use GetArgs to initialize the values.
if (argv) {
for (uint32_t i = 0; i < argc; ++i)
mArgv[i] = argv[i];
}
if (argc > 0) {
mozilla::HoldJSObjects(this);
}
*prv = NS_OK;
}
nsJSArgArray::~nsJSArgArray()
{
ReleaseJSObjects();
}
void
nsJSArgArray::ReleaseJSObjects()
{
if (mArgv) {
delete [] mArgv;
}
if (mArgc > 0) {
mArgc = 0;
mozilla::DropJSObjects(this);
}
}
// QueryInterface implementation for nsJSArgArray
NS_IMPL_CYCLE_COLLECTION_CLASS(nsJSArgArray)
NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(nsJSArgArray)
tmp->ReleaseJSObjects();
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(nsJSArgArray)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_SCRIPT_OBJECTS
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(nsJSArgArray)
if (tmp->mArgv) {
for (uint32_t i = 0; i < tmp->mArgc; ++i) {
NS_IMPL_CYCLE_COLLECTION_TRACE_JSVAL_MEMBER_CALLBACK(mArgv[i])
}
}
NS_IMPL_CYCLE_COLLECTION_TRACE_END
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(nsJSArgArray)
NS_INTERFACE_MAP_ENTRY(nsIArray)
NS_INTERFACE_MAP_ENTRY(nsIJSArgArray)
NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIJSArgArray)
NS_INTERFACE_MAP_END
NS_IMPL_CYCLE_COLLECTING_ADDREF(nsJSArgArray)
NS_IMPL_CYCLE_COLLECTING_RELEASE(nsJSArgArray)
nsresult
nsJSArgArray::GetArgs(uint32_t *argc, void **argv)
{
*argv = (void *)mArgv;
*argc = mArgc;
return NS_OK;
}
// nsIArray impl
NS_IMETHODIMP nsJSArgArray::GetLength(uint32_t *aLength)
{
*aLength = mArgc;
return NS_OK;
}
/* void queryElementAt (in unsigned long index, in nsIIDRef uuid, [iid_is (uuid), retval] out nsQIResult result); */
NS_IMETHODIMP nsJSArgArray::QueryElementAt(uint32_t index, const nsIID & uuid, void * *result)
{
*result = nullptr;
if (index >= mArgc)
return NS_ERROR_INVALID_ARG;
if (uuid.Equals(NS_GET_IID(nsIVariant)) || uuid.Equals(NS_GET_IID(nsISupports))) {
// Have to copy a Heap into a Rooted to work with it.
JS::Rooted<JS::Value> val(mContext, mArgv[index]);
return nsContentUtils::XPConnect()->JSToVariant(mContext, val,
(nsIVariant **)result);
}
NS_WARNING("nsJSArgArray only handles nsIVariant");
return NS_ERROR_NO_INTERFACE;
}
/* unsigned long indexOf (in unsigned long startIndex, in nsISupports element); */
NS_IMETHODIMP nsJSArgArray::IndexOf(uint32_t startIndex, nsISupports *element, uint32_t *_retval)
{
return NS_ERROR_NOT_IMPLEMENTED;
}
/* nsISimpleEnumerator enumerate (); */
NS_IMETHODIMP nsJSArgArray::Enumerate(nsISimpleEnumerator **_retval)
{
return NS_ERROR_NOT_IMPLEMENTED;
}
// The factory function
nsresult NS_CreateJSArgv(JSContext *aContext, uint32_t argc, void *argv,
nsIJSArgArray **aArray)
{
nsresult rv;
nsCOMPtr<nsIJSArgArray> ret = new nsJSArgArray(aContext, argc,
static_cast<JS::Value *>(argv), &rv);
if (NS_FAILED(rv)) {
return rv;
}
ret.forget(aArray);
return NS_OK;
}
