nsISupports* aData, bool aAnonymize) {

MutexAutoLock lock(mTableLock);

MOZ_COLLECT_REPORT(

"explicit/startup-cache/mapping", KIND_NONHEAP, UNITS_BYTES,

mCacheData.nonHeapSizeOfExcludingThis(),

"Memory used to hold the mapping of the startup cache from file. "

"This memory is likely to be swapped out shortly after start-up.");

MOZ_COLLECT_REPORT("explicit/startup-cache/data", KIND_HEAP, UNITS_BYTES,

HeapSizeOfIncludingThis(StartupCacheMallocSizeOf),

"Memory used by the startup cache for things other than "

"the file mapping.");

return NS_OK;

int32_t len) {

if (PR_Write(fd, data, len) != len) {

return Err(NS_ERROR_FAILURE);

}

return Ok();

if (PR_Seek(fd, offset, PR_SEEK_SET) == -1) {

return Err(NS_ERROR_FAILURE);

}

return Ok();

nsresult rv;

StartupCache::gStartupCache = new StartupCache();

rv = StartupCache::gStartupCache->Init();

if (NS_FAILED(rv)) {

StartupCache::gStartupCache = nullptr;

}

return rv;

: mTableLock("StartupCache::mTableLock"),

mDirty(false),

mWrittenOnce(false),

mCurTableReferenced(false),

mRequestedCount(0),

// workaround for bug 653936

nsCOMPtr<nsIProtocolHandler> jarInitializer(

do_GetService(NS_NETWORK_PROTOCOL_CONTRACTID_PREFIX "jar"));

nsresult rv;

if (mozilla::RunningGTest()) {

STARTUP_CACHE_WRITE_TIMEOUT = 3;

}

// This allows to override the startup cache filename

// which is useful from xpcshell, when there is no ProfLDS directory to keep

// cache in.

char* env = PR_GetEnv("MOZ_STARTUP_CACHE");

if (env && *env) {

MOZ_TRY(

NS_NewNativeLocalFile(nsDependentCString(env), getter_AddRefs(mFile)));

} else {

nsCOMPtr<nsIFile> file;

rv = NS_GetSpecialDirectory("ProfLDS", getter_AddRefs(file));

if (NS_FAILED(rv)) {

// return silently, this will fail in mochitests's xpcshell process.

return rv;

}

rv = file->AppendNative("startupCache"_ns);

NS_ENSURE_SUCCESS(rv, rv);

// Try to create the directory if it's not there yet

rv = file->Create(nsIFile::DIRECTORY_TYPE, 0777);

if (NS_FAILED(rv) && rv != NS_ERROR_FILE_ALREADY_EXISTS) return rv;

rv = file->AppendNative(nsLiteralCString(STARTUP_CACHE_NAME));

NS_ENSURE_SUCCESS(rv, rv);

mFile = file.forget();

}

mObserverService = do_GetService("@mozilla.org/observer-service;1");

if (!mObserverService) {

NS_WARNING("Could not get observerService.");

return NS_ERROR_UNEXPECTED;

}

mListener = new StartupCacheListener();

rv = mObserverService->AddObserver(mListener, NS_XPCOM_SHUTDOWN_OBSERVER_ID,

false);

NS_ENSURE_SUCCESS(rv, rv);

rv = mObserverService->AddObserver(mListener, "startupcache-invalidate",

false);

NS_ENSURE_SUCCESS(rv, rv);

rv = mObserverService->AddObserver(mListener, "intl:app-locales-changed",

false);

NS_ENSURE_SUCCESS(rv, rv);

{

MutexAutoLock lock(mTableLock);

auto result = LoadArchive();

rv = result.isErr() ? result.unwrapErr() : NS_OK;

}

gFoundDiskCacheOnInit = rv != NS_ERROR_FILE_NOT_FOUND;

// Sometimes we don't have a cache yet, that's ok.

// If it's corrupted, just remove it and start over.

if (gIgnoreDiskCache || (NS_FAILED(rv) && rv != NS_ERROR_FILE_NOT_FOUND)) {

NS_WARNING("Failed to load startupcache file correctly, removing!");

InvalidateCache();

}

RegisterWeakMemoryReporter(this);

mDecompressionContext = MakeUnique<LZ4FrameDecompressionContext>(true);

return NS_OK;

{

MonitorAutoLock lock(mPrefetchComplete);

mPrefetchInProgress = true;

}

NS_DispatchBackgroundTask(NewRunnableMethod<uint8_t*, size_t>(

"StartupCache::ThreadedPrefetch", this, &StartupCache::ThreadedPrefetch,

mCacheData.get<uint8_t>().get(), mCacheData.size()));

MOZ_ASSERT(NS_IsMainThread(), "Can only load startup cache on main thread");

if (gIgnoreDiskCache) return Err(NS_ERROR_FAILURE);

MOZ_TRY(mCacheData.init(mFile));

auto size = mCacheData.size();

if (CanPrefetchMemory()) {

StartPrefetchMemory();

}

uint32_t headerSize;

if (size < sizeof(MAGIC) + sizeof(headerSize)) {

return Err(NS_ERROR_UNEXPECTED);

}

auto data = mCacheData.get<uint8_t>();

auto end = data + size;

MMAP_FAULT_HANDLER_BEGIN_BUFFER(data.get(), size)

if (memcmp(MAGIC, data.get(), sizeof(MAGIC))) {

return Err(NS_ERROR_UNEXPECTED);

}

data += sizeof(MAGIC);

headerSize = LittleEndian::readUint32(data.get());

data += sizeof(headerSize);

if (headerSize > end - data) {

MOZ_ASSERT(false, "StartupCache file is corrupt.");

return Err(NS_ERROR_UNEXPECTED);

}

Range<const uint8_t> header(data, data + headerSize);

data += headerSize;

mCacheEntriesBaseOffset = sizeof(MAGIC) + sizeof(headerSize) + headerSize;

{

if (!mTable.reserve(STARTUP_CACHE_RESERVE_CAPACITY)) {

return Err(NS_ERROR_UNEXPECTED);

}

auto cleanup = MakeScopeExit([&]() {

mTableLock.AssertCurrentThreadOwns();

WaitOnPrefetch();

mTable.clear();

mCacheData.reset();

});

loader::InputBuffer buf(header);

uint32_t currentOffset = 0;

while (!buf.finished()) {

uint32_t offset = 0;

uint32_t compressedSize = 0;

uint32_t uncompressedSize = 0;

nsCString key;

buf.codeUint32(offset);

buf.codeUint32(compressedSize);

buf.codeUint32(uncompressedSize);

buf.codeString(key);

if (offset + compressedSize > end - data) {

MOZ_ASSERT(false, "StartupCache file is corrupt.");

return Err(NS_ERROR_UNEXPECTED);

}

// Make sure offsets match what we'd expect based on script ordering and

// size, as a basic sanity check.

if (offset != currentOffset) {

return Err(NS_ERROR_UNEXPECTED);

}

currentOffset += compressedSize;

// We could use mTable.putNew if we knew the file we're loading weren't

// corrupt. However, we don't know that, so check if the key already

// exists. If it does, we know the file must be corrupt.

decltype(mTable)::AddPtr p = mTable.lookupForAdd(key);

if (p) {

return Err(NS_ERROR_UNEXPECTED);

}

if (!mTable.add(

p, key,

StartupCacheEntry(offset, compressedSize, uncompressedSize))) {

return Err(NS_ERROR_UNEXPECTED);

}

}

if (buf.error()) {

return Err(NS_ERROR_UNEXPECTED);

}

cleanup.release();

}

MMAP_FAULT_HANDLER_CATCH(Err(NS_ERROR_UNEXPECTED))

return Ok();

AUTO_PROFILER_LABEL("StartupCache::HasEntry", OTHER);

MOZ_ASSERT(NS_IsMainThread(), "Startup cache only available on main thread");

MutexAutoLock lock(mTableLock);

return mTable.has(nsDependentCString(id));

uint32_t* length)

MOZ_NO_THREAD_SAFETY_ANALYSIS {

AUTO_PROFILER_LABEL("StartupCache::GetBuffer", OTHER);

NS_ASSERTION(NS_IsMainThread(),

"Startup cache only available on main thread");

auto label = glean::startup_cache::RequestsLabel::eMiss;

auto telemetry = MakeScopeExit(

[&label] { glean::startup_cache::requests.EnumGet(label).Add(); });

MutexAutoLock lock(mTableLock);

decltype(mTable)::Ptr p = mTable.lookup(nsDependentCString(id));

if (!p) {

return NS_ERROR_NOT_AVAILABLE;

}

auto& value = p->value();

if (value.mData) {

label = glean::startup_cache::RequestsLabel::eHitmemory;

} else {

if (!mCacheData.initialized()) {

return NS_ERROR_NOT_AVAILABLE;

}

// It is impossible for a write to be pending here. This is because

// we just checked mCacheData.initialized(), and this is reset before

// writing to the cache. It's not re-initialized unless we call

// LoadArchive(), either from Init() (which must have already happened) or

// InvalidateCache(). InvalidateCache() locks the mutex, so a write can't be

// happening.

// Also, WriteToDisk() requires mTableLock, so while it's writing we can't

// be here.

size_t totalRead = 0;

size_t totalWritten = 0;

Span<const char> compressed = Span(

mCacheData.get<char>().get() + mCacheEntriesBaseOffset + value.mOffset,

value.mCompressedSize);

value.mData = UniqueFreePtr<char[]>(reinterpret_cast<char*>(

malloc(sizeof(char) * value.mUncompressedSize)));

Span<char> uncompressed = Span(value.mData.get(), value.mUncompressedSize);

MMAP_FAULT_HANDLER_BEGIN_BUFFER(uncompressed.Elements(),

uncompressed.Length())

bool finished = false;

while (!finished) {

auto result = mDecompressionContext->Decompress(

uncompressed.From(totalWritten), compressed.From(totalRead));

if (NS_WARN_IF(result.isErr())) {

value.mData = nullptr;

MutexAutoUnlock unlock(mTableLock);

InvalidateCache();

return NS_ERROR_FAILURE;

}

auto decompressionResult = result.unwrap();

totalRead += decompressionResult.mSizeRead;

totalWritten += decompressionResult.mSizeWritten;

finished = decompressionResult.mFinished;

}

MMAP_FAULT_HANDLER_CATCH(NS_ERROR_FAILURE)

label = glean::startup_cache::RequestsLabel::eHitdisk;

}

if (!value.mRequested) {

value.mRequested = true;

value.mRequestedOrder = ++mRequestedCount;

MOZ_ASSERT(mRequestedCount <= mTable.count(),

"Somehow we requested more StartupCache items than exist.");

ResetStartupWriteTimerCheckingReadCount();

}

// Track that something holds a reference into mTable, so we know to hold

// onto it in case the cache is invalidated.

mCurTableReferenced = true;

*outbuf = value.mData.get();

*length = value.mUncompressedSize;

return NS_OK;

uint32_t len) MOZ_NO_THREAD_SAFETY_ANALYSIS {

NS_ASSERTION(NS_IsMainThread(),

"Startup cache only available on main thread");

if (StartupCache::gShutdownInitiated) {

return NS_ERROR_NOT_AVAILABLE;

}

// Try to gain the table write lock. If the background task to write the

// cache is running, this will fail.

MutexAutoTryLock lock(mTableLock);

if (!lock) {

return NS_ERROR_NOT_AVAILABLE;

}

mTableLock.AssertCurrentThreadOwns();

bool exists = mTable.has(nsDependentCString(id));

if (exists) {

NS_WARNING("Existing entry in StartupCache.");

// Double-caching is undesirable but not an error.

return NS_OK;

}

// putNew returns false on alloc failure - in the very unlikely event we hit

// that and aren't going to crash elsewhere, there's no reason we need to

// crash here.

if (mTable.putNew(nsCString(id), StartupCacheEntry(std::move(inbuf), len,

++mRequestedCount))) {

return ResetStartupWriteTimer();

}

MOZ_DIAGNOSTIC_ASSERT(mTable.count() < STARTUP_CACHE_MAX_CAPACITY,

"Too many StartupCache entries.");

return NS_OK;

mozilla::MallocSizeOf aMallocSizeOf) const {

// This function could measure more members, but they haven't been found by

// DMD to be significant. They can be added later if necessary.

size_t n = aMallocSizeOf(this);

n += mTable.shallowSizeOfExcludingThis(aMallocSizeOf);

for (auto iter = mTable.iter(); !iter.done(); iter.next()) {

if (iter.get().value().mData) {

n += aMallocSizeOf(iter.get().value().mData.get());

}

n += iter.get().key().SizeOfExcludingThisIfUnshared(aMallocSizeOf);

}

return n;

if (!mDirty || mWrittenOnce) {

return Ok();

}

if (!mFile) {

return Err(NS_ERROR_UNEXPECTED);

}

AutoFDClose raiiFd;

MOZ_TRY(mFile->OpenNSPRFileDesc(PR_WRONLY | PR_CREATE_FILE | PR_TRUNCATE,

0644, getter_Transfers(raiiFd)));

const auto fd = raiiFd.get();

nsTArray<StartupCacheEntry::KeyValuePair> entries(mTable.count());

for (auto iter = mTable.iter(); !iter.done(); iter.next()) {

if (iter.get().value().mRequested) {

StartupCacheEntry::KeyValuePair kv(&iter.get().key(),

&iter.get().value());

entries.AppendElement(kv);

}

}

if (entries.IsEmpty()) {

return Ok();

}

entries.Sort(StartupCacheEntry::Comparator());

loader::OutputBuffer buf;

for (auto& e : entries) {

auto* key = e.first;

auto* value = e.second;

auto uncompressedSize = value->mUncompressedSize;

// Set the mHeaderOffsetInFile so we can go back and edit the offset.

value->mHeaderOffsetInFile = buf.cursor();

// Write a 0 offset/compressed size as a placeholder until we get the real

// offset after compressing.

buf.codeUint32(0);

buf.codeUint32(0);

buf.codeUint32(uncompressedSize);

buf.codeString(*key);

}

uint8_t headerSize[4];

LittleEndian::writeUint32(headerSize, buf.cursor());

MOZ_TRY(Write(fd, MAGIC, sizeof(MAGIC)));

MOZ_TRY(Write(fd, headerSize, sizeof(headerSize)));

size_t headerStart = sizeof(MAGIC) + sizeof(headerSize);

size_t dataStart = headerStart + buf.cursor();

MOZ_TRY(Seek(fd, dataStart));

size_t offset = 0;

const size_t chunkSize = 1024 * 16;

LZ4FrameCompressionContext ctx(6, /* aCompressionLevel */

chunkSize, /* aReadBufLen */

true, /* aChecksum */

true); /* aStableSrc */

size_t writeBufLen = ctx.GetRequiredWriteBufferLength();

auto writeBuffer = MakeUnique<char[]>(writeBufLen);

auto writeSpan = Span(writeBuffer.get(), writeBufLen);

for (auto& e : entries) {

auto value = e.second;

value->mOffset = offset;

Span<const char> result;

MOZ_TRY_VAR(result,

ctx.BeginCompressing(writeSpan).mapErr(MapLZ4ErrorToNsresult));

MOZ_TRY(Write(fd, result.Elements(), result.Length()));

offset += result.Length();

for (size_t i = 0; i < value->mUncompressedSize; i += chunkSize) {

size_t size = std::min(chunkSize, value->mUncompressedSize - i);

char* uncompressed = value->mData.get() + i;

MOZ_TRY_VAR(result, ctx.ContinueCompressing(Span(uncompressed, size))

.mapErr(MapLZ4ErrorToNsresult));

MOZ_TRY(Write(fd, result.Elements(), result.Length()));

offset += result.Length();

}

MOZ_TRY_VAR(result, ctx.EndCompressing().mapErr(MapLZ4ErrorToNsresult));

MOZ_TRY(Write(fd, result.Elements(), result.Length()));

offset += result.Length();

value->mCompressedSize = offset - value->mOffset;

MOZ_TRY(Seek(fd, dataStart + offset));

}

for (auto& e : entries) {

auto value = e.second;

uint8_t* headerEntry = buf.Get() + value->mHeaderOffsetInFile;

LittleEndian::writeUint32(headerEntry, value->mOffset);

LittleEndian::writeUint32(headerEntry + sizeof(value->mOffset),

value->mCompressedSize);

}

MOZ_TRY(Seek(fd, headerStart));

MOZ_TRY(Write(fd, buf.Get(), buf.cursor()));

mDirty = false;

mWrittenOnce = true;

return Ok();

WaitOnPrefetch();

// Ensure we're not writing using mTable...

MutexAutoLock lock(mTableLock);

mWrittenOnce = false;

if (memoryOnly) {

// This should only be called in tests.

auto writeResult = WriteToDisk();

if (NS_WARN_IF(writeResult.isErr())) {

gIgnoreDiskCache = true;

return;

}

}

if (mCurTableReferenced) {

// There should be no way for this assert to fail other than a user manually

// sending startupcache-invalidate messages through the Browser Toolbox. If

// something knowingly invalidates the cache, the event can be counted with

// mAllowedInvalidationsCount.

MOZ_DIAGNOSTIC_ASSERT(

xpc::IsInAutomation() ||

// The allowed invalidations can grow faster than the old tables, so

// guard against incorrect unsigned subtraction.

mAllowedInvalidationsCount > mOldTables.Length() ||

// Now perform the real check.

mOldTables.Length() - mAllowedInvalidationsCount < 10,

"Startup cache invalidated too many times.");

mOldTables.AppendElement(std::move(mTable));

mCurTableReferenced = false;

} else {

mTable.clear();

}

mRequestedCount = 0;

if (!memoryOnly) {

mCacheData.reset();

nsresult rv = mFile->Remove(false);

if (NS_FAILED(rv) && rv != NS_ERROR_FILE_NOT_FOUND) {

gIgnoreDiskCache = true;

return;

}

}

gIgnoreDiskCache = false;

auto result = LoadArchive();

if (NS_WARN_IF(result.isErr())) {

gIgnoreDiskCache = true;

}

if (mTimer) {

mTimer->Cancel();

}

gShutdownInitiated = true;

MaybeWriteOffMainThread();

MutexAutoLock lock(mTableLock);

// If we've already written or there's nothing to write,

// we don't need to do anything. This is the common case.

if (mWrittenOnce || (mCacheData.initialized() && !ShouldCompactCache())) {

return;

}

// Otherwise, ensure the write happens. The timer should have been cancelled

// already in MaybeInitShutdownWrite.

// We got the lock. Keep the following in sync with

// MaybeWriteOffMainThread:

WaitOnPrefetch();

mDirty = true;

mCacheData.reset();

// Most of this should be redundant given MaybeWriteOffMainThread should

// have run before now.

auto writeResult = WriteToDisk();

Unused << NS_WARN_IF(writeResult.isErr());

// We've had the lock, and `WriteToDisk()` sets mWrittenOnce and mDirty

// when done, and checks for them when starting, so we don't need to do

// anything else.

// This can't be called from within ThreadedPrefetch()

MonitorAutoLock lock(mPrefetchComplete);

while (mPrefetchInProgress) {

mPrefetchComplete.Wait();

}

// Always notify of completion, even if MMAP_FAULT_HANDLER_CATCH()

// early-returns.

auto notifyPrefetchComplete = MakeScopeExit([&] {

MonitorAutoLock lock(mPrefetchComplete);

mPrefetchInProgress = false;

mPrefetchComplete.NotifyAll();

});

// PrefetchMemory does madvise/equivalent, but doesn't access the memory

// pointed to by aStart

MMAP_FAULT_HANDLER_BEGIN_BUFFER(aStart, aSize)

PrefetchMemory(aStart, aSize);

MMAP_FAULT_HANDLER_CATCH()

// If we've requested less than 4/5 of the startup cache, then we should

// probably compact it down. This can happen quite easily after the first run,

// which seems to request quite a few more things than subsequent runs.

CheckedInt<uint32_t> threshold = CheckedInt<uint32_t>(mTable.count()) * 4 / 5;

MOZ_RELEASE_ASSERT(threshold.isValid(), "Runaway StartupCache size");

return mRequestedCount < threshold.value();

/*

StartupCache* startupCacheObj = static_cast<StartupCache*>(aClosure);

startupCacheObj->MaybeWriteOffMainThread();

{

MutexAutoLock lock(mTableLock);

if (mWrittenOnce || (mCacheData.initialized() && !ShouldCompactCache())) {

return;

}

}

// Keep this code in sync with EnsureShutdownWriteComplete.

WaitOnPrefetch();

{

MutexAutoLock lock(mTableLock);

mDirty = true;

mCacheData.reset();

}

RefPtr<StartupCache> self = this;

nsCOMPtr<nsIRunnable> runnable =

NS_NewRunnableFunction("StartupCache::Write", [self]() mutable {

MutexAutoLock lock(self->mTableLock);

auto result = self->WriteToDisk();

Unused << NS_WARN_IF(result.isErr());

});

NS_DispatchBackgroundTask(runnable.forget(), NS_DISPATCH_EVENT_MAY_BLOCK);

const char16_t* data) {

StartupCache* sc = StartupCache::GetSingleton();

if (!sc) return NS_OK;

if (strcmp(topic, NS_XPCOM_SHUTDOWN_OBSERVER_ID) == 0) {

// Do not leave the thread running past xpcom shutdown

sc->WaitOnPrefetch();

StartupCache::gShutdownInitiated = true;

// Note that we don't do anything special for the background write

// task; we expect the threadpool to finish running any tasks already

// posted to it prior to shutdown. FastShutdown will call

// EnsureShutdownWriteComplete() to ensure any pending writes happen

// in that case.

} else if (strcmp(topic, "startupcache-invalidate") == 0) {

sc->InvalidateCache(data && nsCRT::strcmp(data, u"memoryOnly") == 0);

} else if (strcmp(topic, "intl:app-locales-changed") == 0) {

// Live language switching invalidates the startup cache due to the history

// sidebar retaining localized strings in its internal SQL query. This

// should be a relatively rare event, but a user could do it an arbitrary

// number of times.

sc->CountAllowedInvalidation();

}

return NS_OK;

nsIObjectOutputStream* aStream, nsIObjectOutputStream** aOutStream) {

NS_ENSURE_ARG_POINTER(aStream);

#ifdef DEBUG

auto* stream = new StartupCacheDebugOutputStream(aStream, &mWriteObjectMap);

NS_ADDREF(*aOutStream = stream);

#else

NS_ADDREF(*aOutStream = aStream);

#endif

return NS_OK;

nsresult rv = NS_OK;

if (!mTimer)

mTimer = NS_NewTimer();

else

rv = mTimer->Cancel();

NS_ENSURE_SUCCESS(rv, rv);

// Wait for the specified timeout, then write out the cache.

mTimer->InitWithNamedFuncCallback(

StartupCache::WriteTimeout, this, STARTUP_CACHE_WRITE_TIMEOUT * 1000,

nsITimer::TYPE_ONE_SHOT, "StartupCache::WriteTimeout");

return NS_OK;

mDirty = true;

nsresult rv = NS_OK;

if (!mTimer)

mTimer = NS_NewTimer();

else

rv = mTimer->Cancel();

NS_ENSURE_SUCCESS(rv, rv);

// Wait for the specified timeout, then write out the cache.

mTimer->InitWithNamedFuncCallback(

StartupCache::WriteTimeout, this, STARTUP_CACHE_WRITE_TIMEOUT * 1000,

nsITimer::TYPE_ONE_SHOT, "StartupCache::WriteTimeout");

return NS_OK;

// Need to have written to disk and not added new things since;

MutexAutoLock lock(mTableLock);

return !mDirty && mWrittenOnce;

nsresult rv;

nsCOMPtr<nsIClassInfo> classInfo = do_QueryInterface(aObject);

if (!classInfo) {

NS_ERROR("aObject must implement nsIClassInfo");

return false;

}

uint32_t flags;

rv = classInfo->GetFlags(&flags);

NS_ENSURE_SUCCESS(rv, false);

if (flags & nsIClassInfo::SINGLETON) return true;

bool inserted = mObjectMap->EnsureInserted(aObject);

if (!inserted) {

NS_ERROR(

"non-singleton aObject is referenced multiple times in this"

"serialization, we don't support that.");

}

return inserted;

bool aIsStrongRef) {

nsCOMPtr<nsISupports> rootObject(do_QueryInterface(aObject));

NS_ASSERTION(rootObject.get() == aObject,

"bad call to WriteObject -- call WriteCompoundObject!");

bool check = CheckReferences(aObject);

NS_ENSURE_TRUE(check, NS_ERROR_FAILURE);

return mBinaryStream->WriteObject(aObject, aIsStrongRef);

nsISupports* aObject) {

nsCOMPtr<nsISupports> rootObject(do_QueryInterface(aObject));

NS_ASSERTION(rootObject.get() == aObject,

"bad call to WriteSingleRefObject -- call WriteCompoundObject!");

bool check = CheckReferences(aObject);

NS_ENSURE_TRUE(check, NS_ERROR_FAILURE);

return mBinaryStream->WriteSingleRefObject(aObject);

nsISupports* aObject, const nsIID& aIID, bool aIsStrongRef) {

nsCOMPtr<nsISupports> rootObject(do_QueryInterface(aObject));

nsCOMPtr<nsISupports> roundtrip;

rootObject->QueryInterface(aIID, getter_AddRefs(roundtrip));

NS_ASSERTION(roundtrip.get() == aObject,

"bad aggregation or multiple inheritance detected by call to "

"WriteCompoundObject!");

bool check = CheckReferences(aObject);

NS_ENSURE_TRUE(check, NS_ERROR_FAILURE);

return mBinaryStream->WriteCompoundObject(aObject, aIID, aIsStrongRef);