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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
commit36d22d82aa202bb199967e9512281e9a53db42c9 (patch)
tree105e8c98ddea1c1e4784a60a5a6410fa416be2de /tools/profiler/gecko/ProfilerChild.cpp
parentInitial commit. (diff)
downloadfirefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.tar.xz
firefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.zip
Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--tools/profiler/gecko/ProfilerChild.cpp565
1 files changed, 565 insertions, 0 deletions
diff --git a/tools/profiler/gecko/ProfilerChild.cpp b/tools/profiler/gecko/ProfilerChild.cpp
new file mode 100644
index 0000000000..db7ef99423
--- /dev/null
+++ b/tools/profiler/gecko/ProfilerChild.cpp
@@ -0,0 +1,565 @@
+/* -*- 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 "ProfilerChild.h"
+
+#include "GeckoProfiler.h"
+#include "platform.h"
+#include "ProfilerCodeAddressService.h"
+#include "ProfilerControl.h"
+#include "ProfilerParent.h"
+
+#include "chrome/common/ipc_channel.h"
+#include "nsPrintfCString.h"
+#include "nsThreadUtils.h"
+
+#include <memory>
+
+namespace mozilla {
+
+/* static */ DataMutexBase<ProfilerChild::ProfilerChildAndUpdate,
+ baseprofiler::detail::BaseProfilerMutex>
+ ProfilerChild::sPendingChunkManagerUpdate{
+ "ProfilerChild::sPendingChunkManagerUpdate"};
+
+ProfilerChild::ProfilerChild()
+ : mThread(NS_GetCurrentThread()), mDestroyed(false) {
+ MOZ_COUNT_CTOR(ProfilerChild);
+}
+
+ProfilerChild::~ProfilerChild() { MOZ_COUNT_DTOR(ProfilerChild); }
+
+void ProfilerChild::ResolveChunkUpdate(
+ PProfilerChild::AwaitNextChunkManagerUpdateResolver& aResolve) {
+ MOZ_ASSERT(!!aResolve,
+ "ResolveChunkUpdate should only be called when there's a pending "
+ "resolver");
+ MOZ_ASSERT(
+ !mChunkManagerUpdate.IsNotUpdate(),
+ "ResolveChunkUpdate should only be called with a real or final update");
+ MOZ_ASSERT(
+ !mDestroyed,
+ "ResolveChunkUpdate should not be called if the actor was destroyed");
+ if (mChunkManagerUpdate.IsFinal()) {
+ // Final update, send a special "unreleased value", but don't clear the
+ // local copy so we know we got the final update.
+ std::move(aResolve)(ProfilerParent::MakeFinalUpdate());
+ } else {
+ // Optimization note: The ProfileBufferChunkManagerUpdate constructor takes
+ // the newly-released chunks nsTArray by reference-to-const, therefore
+ // constructing and then moving the array here would make a copy. So instead
+ // we first give it an empty array, and then we can write the data directly
+ // into the update's array.
+ ProfileBufferChunkManagerUpdate update{
+ mChunkManagerUpdate.UnreleasedBytes(),
+ mChunkManagerUpdate.ReleasedBytes(),
+ mChunkManagerUpdate.OldestDoneTimeStamp(),
+ {}};
+ update.newlyReleasedChunks().SetCapacity(
+ mChunkManagerUpdate.NewlyReleasedChunksRef().size());
+ for (const ProfileBufferControlledChunkManager::ChunkMetadata& chunk :
+ mChunkManagerUpdate.NewlyReleasedChunksRef()) {
+ update.newlyReleasedChunks().EmplaceBack(chunk.mDoneTimeStamp,
+ chunk.mBufferBytes);
+ }
+
+ std::move(aResolve)(update);
+
+ // Clear the update we just sent, so it's ready for later updates to be
+ // folded into it.
+ mChunkManagerUpdate.Clear();
+ }
+
+ // Discard the resolver, so it's empty next time there's a new request.
+ aResolve = nullptr;
+}
+
+void ProfilerChild::ProcessChunkManagerUpdate(
+ ProfileBufferControlledChunkManager::Update&& aUpdate) {
+ if (mDestroyed) {
+ return;
+ }
+ // Always store the data, it could be the final update.
+ mChunkManagerUpdate.Fold(std::move(aUpdate));
+ if (mAwaitNextChunkManagerUpdateResolver) {
+ // There is already a pending resolver, give it the info now.
+ ResolveChunkUpdate(mAwaitNextChunkManagerUpdateResolver);
+ }
+}
+
+/* static */ void ProfilerChild::ProcessPendingUpdate() {
+ auto lockedUpdate = sPendingChunkManagerUpdate.Lock();
+ if (!lockedUpdate->mProfilerChild || lockedUpdate->mUpdate.IsNotUpdate()) {
+ return;
+ }
+ lockedUpdate->mProfilerChild->mThread->Dispatch(NS_NewRunnableFunction(
+ "ProfilerChild::ProcessPendingUpdate", []() mutable {
+ auto lockedUpdate = sPendingChunkManagerUpdate.Lock();
+ if (!lockedUpdate->mProfilerChild ||
+ lockedUpdate->mUpdate.IsNotUpdate()) {
+ return;
+ }
+ lockedUpdate->mProfilerChild->ProcessChunkManagerUpdate(
+ std::move(lockedUpdate->mUpdate));
+ lockedUpdate->mUpdate.Clear();
+ }));
+}
+
+/* static */ bool ProfilerChild::IsLockedOnCurrentThread() {
+ return sPendingChunkManagerUpdate.Mutex().IsLockedOnCurrentThread();
+}
+
+void ProfilerChild::SetupChunkManager() {
+ mChunkManager = profiler_get_controlled_chunk_manager();
+ if (NS_WARN_IF(!mChunkManager)) {
+ return;
+ }
+
+ // Make sure there are no updates (from a previous run).
+ mChunkManagerUpdate.Clear();
+ {
+ auto lockedUpdate = sPendingChunkManagerUpdate.Lock();
+ lockedUpdate->mProfilerChild = this;
+ lockedUpdate->mUpdate.Clear();
+ }
+
+ mChunkManager->SetUpdateCallback(
+ [](ProfileBufferControlledChunkManager::Update&& aUpdate) {
+ // Updates from the chunk manager are stored for later processing.
+ // We avoid dispatching a task, as this could deadlock (if the queueing
+ // mutex is held elsewhere).
+ auto lockedUpdate = sPendingChunkManagerUpdate.Lock();
+ if (!lockedUpdate->mProfilerChild) {
+ return;
+ }
+ lockedUpdate->mUpdate.Fold(std::move(aUpdate));
+ });
+}
+
+void ProfilerChild::ResetChunkManager() {
+ if (!mChunkManager) {
+ return;
+ }
+
+ // We have a chunk manager, reset the callback, which will add a final
+ // pending update.
+ mChunkManager->SetUpdateCallback({});
+
+ // Clear the pending update.
+ auto lockedUpdate = sPendingChunkManagerUpdate.Lock();
+ lockedUpdate->mProfilerChild = nullptr;
+ lockedUpdate->mUpdate.Clear();
+ // And process a final update right now.
+ ProcessChunkManagerUpdate(
+ ProfileBufferControlledChunkManager::Update(nullptr));
+
+ mChunkManager = nullptr;
+ mAwaitNextChunkManagerUpdateResolver = nullptr;
+}
+
+mozilla::ipc::IPCResult ProfilerChild::RecvStart(
+ const ProfilerInitParams& params, StartResolver&& aResolve) {
+ nsTArray<const char*> filterArray;
+ for (size_t i = 0; i < params.filters().Length(); ++i) {
+ filterArray.AppendElement(params.filters()[i].get());
+ }
+
+ profiler_start(PowerOfTwo32(params.entries()), params.interval(),
+ params.features(), filterArray.Elements(),
+ filterArray.Length(), params.activeTabID(), params.duration());
+
+ SetupChunkManager();
+
+ aResolve(/* unused */ true);
+ return IPC_OK();
+}
+
+mozilla::ipc::IPCResult ProfilerChild::RecvEnsureStarted(
+ const ProfilerInitParams& params, EnsureStartedResolver&& aResolve) {
+ nsTArray<const char*> filterArray;
+ for (size_t i = 0; i < params.filters().Length(); ++i) {
+ filterArray.AppendElement(params.filters()[i].get());
+ }
+
+ profiler_ensure_started(PowerOfTwo32(params.entries()), params.interval(),
+ params.features(), filterArray.Elements(),
+ filterArray.Length(), params.activeTabID(),
+ params.duration());
+
+ SetupChunkManager();
+
+ aResolve(/* unused */ true);
+ return IPC_OK();
+}
+
+mozilla::ipc::IPCResult ProfilerChild::RecvStop(StopResolver&& aResolve) {
+ ResetChunkManager();
+ profiler_stop();
+ aResolve(/* unused */ true);
+ return IPC_OK();
+}
+
+mozilla::ipc::IPCResult ProfilerChild::RecvPause(PauseResolver&& aResolve) {
+ profiler_pause();
+ aResolve(/* unused */ true);
+ return IPC_OK();
+}
+
+mozilla::ipc::IPCResult ProfilerChild::RecvResume(ResumeResolver&& aResolve) {
+ profiler_resume();
+ aResolve(/* unused */ true);
+ return IPC_OK();
+}
+
+mozilla::ipc::IPCResult ProfilerChild::RecvPauseSampling(
+ PauseSamplingResolver&& aResolve) {
+ profiler_pause_sampling();
+ aResolve(/* unused */ true);
+ return IPC_OK();
+}
+
+mozilla::ipc::IPCResult ProfilerChild::RecvResumeSampling(
+ ResumeSamplingResolver&& aResolve) {
+ profiler_resume_sampling();
+ aResolve(/* unused */ true);
+ return IPC_OK();
+}
+
+mozilla::ipc::IPCResult ProfilerChild::RecvWaitOnePeriodicSampling(
+ WaitOnePeriodicSamplingResolver&& aResolve) {
+ std::shared_ptr<WaitOnePeriodicSamplingResolver> resolve =
+ std::make_shared<WaitOnePeriodicSamplingResolver>(std::move(aResolve));
+ if (!profiler_callback_after_sampling(
+ [self = RefPtr(this), resolve](SamplingState aSamplingState) mutable {
+ if (self->mDestroyed) {
+ return;
+ }
+ MOZ_RELEASE_ASSERT(self->mThread);
+ self->mThread->Dispatch(NS_NewRunnableFunction(
+ "nsProfiler::WaitOnePeriodicSampling result on main thread",
+ [resolve = std::move(resolve), aSamplingState]() {
+ (*resolve)(aSamplingState ==
+ SamplingState::SamplingCompleted ||
+ aSamplingState ==
+ SamplingState::NoStackSamplingCompleted);
+ }));
+ })) {
+ // Callback was not added (e.g., profiler is not running) and will never be
+ // invoked, so we need to resolve the promise here.
+ (*resolve)(false);
+ }
+ return IPC_OK();
+}
+
+mozilla::ipc::IPCResult ProfilerChild::RecvClearAllPages() {
+ profiler_clear_all_pages();
+ return IPC_OK();
+}
+
+mozilla::ipc::IPCResult ProfilerChild::RecvAwaitNextChunkManagerUpdate(
+ AwaitNextChunkManagerUpdateResolver&& aResolve) {
+ MOZ_ASSERT(!mDestroyed,
+ "Recv... should not be called if the actor was destroyed");
+ // Pick up pending updates if any.
+ {
+ auto lockedUpdate = sPendingChunkManagerUpdate.Lock();
+ if (lockedUpdate->mProfilerChild && !lockedUpdate->mUpdate.IsNotUpdate()) {
+ mChunkManagerUpdate.Fold(std::move(lockedUpdate->mUpdate));
+ lockedUpdate->mUpdate.Clear();
+ }
+ }
+ if (mChunkManagerUpdate.IsNotUpdate()) {
+ // No data yet, store the resolver for later.
+ mAwaitNextChunkManagerUpdateResolver = std::move(aResolve);
+ } else {
+ // We have data, send it now.
+ ResolveChunkUpdate(aResolve);
+ }
+ return IPC_OK();
+}
+
+mozilla::ipc::IPCResult ProfilerChild::RecvDestroyReleasedChunksAtOrBefore(
+ const TimeStamp& aTimeStamp) {
+ if (mChunkManager) {
+ mChunkManager->DestroyChunksAtOrBefore(aTimeStamp);
+ }
+ return IPC_OK();
+}
+
+struct GatherProfileThreadParameters
+ : public external::AtomicRefCounted<GatherProfileThreadParameters> {
+ MOZ_DECLARE_REFCOUNTED_TYPENAME(GatherProfileThreadParameters)
+
+ GatherProfileThreadParameters(
+ RefPtr<ProfilerChild> aProfilerChild,
+ RefPtr<ProgressLogger::SharedProgress> aProgress,
+ ProfilerChild::GatherProfileResolver&& aResolver)
+ : profilerChild(std::move(aProfilerChild)),
+ progress(std::move(aProgress)),
+ resolver(std::move(aResolver)) {}
+
+ RefPtr<ProfilerChild> profilerChild;
+
+ FailureLatchSource failureLatchSource;
+
+ // Separate RefPtr used when working on separate thread. This way, if the
+ // "ProfilerChild" thread decides to overwrite its mGatherProfileProgress with
+ // a new one, the work done here will still only use the old one.
+ RefPtr<ProgressLogger::SharedProgress> progress;
+
+ // Resolver for the GatherProfile promise. Must only be called on the
+ // "ProfilerChild" thread.
+ ProfilerChild::GatherProfileResolver resolver;
+};
+
+/* static */
+void ProfilerChild::GatherProfileThreadFunction(
+ void* already_AddRefedParameters) {
+ PR_SetCurrentThreadName("GatherProfileThread");
+
+ RefPtr<GatherProfileThreadParameters> parameters =
+ already_AddRefed<GatherProfileThreadParameters>{
+ static_cast<GatherProfileThreadParameters*>(
+ already_AddRefedParameters)};
+
+ ProgressLogger progressLogger(
+ parameters->progress, "Gather-profile thread started", "Profile sent");
+ using namespace mozilla::literals::ProportionValue_literals; // For `1_pc`.
+
+ auto writer =
+ MakeUnique<SpliceableChunkedJSONWriter>(parameters->failureLatchSource);
+ if (!profiler_get_profile_json(
+ *writer,
+ /* aSinceTime */ 0,
+ /* aIsShuttingDown */ false,
+ progressLogger.CreateSubLoggerFromTo(
+ 1_pc, "profiler_get_profile_json started", 99_pc,
+ "profiler_get_profile_json done"))) {
+ // Failed to get a profile, reset the writer pointer, so that we'll send a
+ // failure message.
+ writer.reset();
+ }
+
+ if (NS_WARN_IF(NS_FAILED(
+ parameters->profilerChild->mThread->Dispatch(NS_NewRunnableFunction(
+ "ProfilerChild::ProcessPendingUpdate",
+ [parameters,
+ // Forward progress logger to on-ProfilerChild-thread task, so
+ // that it doesn't get marked as 100% done when this off-thread
+ // function ends.
+ progressLogger = std::move(progressLogger),
+ writer = std::move(writer)]() mutable {
+ // We are now on the ProfilerChild thread, about to send the
+ // completed profile. Any incoming progress request will now be
+ // handled after this task ends, so updating the progress is now
+ // useless and we can just get rid of the progress storage.
+ if (parameters->profilerChild->mGatherProfileProgress ==
+ parameters->progress) {
+ // The ProfilerChild progress is still the one we know.
+ parameters->profilerChild->mGatherProfileProgress = nullptr;
+ }
+
+ // Shmem allocation and promise resolution must be made on the
+ // ProfilerChild thread, that's why this task was needed here.
+ mozilla::ipc::Shmem shmem;
+ if (writer) {
+ if (const size_t len = writer->ChunkedWriteFunc().Length();
+ len < UINT32_MAX) {
+ bool shmemSuccess = true;
+ const bool copySuccess =
+ writer->ChunkedWriteFunc()
+ .CopyDataIntoLazilyAllocatedBuffer(
+ [&](size_t allocationSize) -> char* {
+ MOZ_ASSERT(allocationSize == len + 1);
+ if (parameters->profilerChild->AllocShmem(
+ allocationSize, &shmem)) {
+ return shmem.get<char>();
+ }
+ shmemSuccess = false;
+ return nullptr;
+ });
+ if (!shmemSuccess || !copySuccess) {
+ const nsPrintfCString message(
+ (!shmemSuccess)
+ ? "*Could not create shmem for profile from pid "
+ "%u (%zu B)"
+ : "*Could not write profile from pid %u (%zu B)",
+ unsigned(profiler_current_process_id().ToNumber()),
+ len);
+ if (parameters->profilerChild->AllocShmem(
+ message.Length() + 1, &shmem)) {
+ strcpy(shmem.get<char>(), message.Data());
+ }
+ }
+ } else {
+ const nsPrintfCString message(
+ "*Profile from pid %u bigger (%zu) than shmem max "
+ "(%zu)",
+ unsigned(profiler_current_process_id().ToNumber()), len,
+ size_t(UINT32_MAX));
+ if (parameters->profilerChild->AllocShmem(
+ message.Length() + 1, &shmem)) {
+ strcpy(shmem.get<char>(), message.Data());
+ }
+ }
+ writer = nullptr;
+ } else {
+ // No profile.
+ const char* failure =
+ parameters->failureLatchSource.GetFailure();
+ const nsPrintfCString message(
+ "*Could not generate profile from pid %u%s%s",
+ unsigned(profiler_current_process_id().ToNumber()),
+ failure ? ", failure: " : "", failure ? failure : "");
+ if (parameters->profilerChild->AllocShmem(
+ message.Length() + 1, &shmem)) {
+ strcpy(shmem.get<char>(), message.Data());
+ }
+ }
+
+ SharedLibraryInfo sharedLibraryInfo =
+ SharedLibraryInfo::GetInfoForSelf();
+ parameters->resolver(IPCProfileAndAdditionalInformation{
+ shmem, Some(ProfileGenerationAdditionalInformation{
+ std::move(sharedLibraryInfo)})});
+ }))))) {
+ // Failed to dispatch the task to the ProfilerChild thread. The IPC cannot
+ // be resolved on this thread, so it will never be resolved!
+ // And it would be unsafe to modify mGatherProfileProgress; But the parent
+ // should notice that's it's not advancing anymore.
+ }
+}
+
+mozilla::ipc::IPCResult ProfilerChild::RecvGatherProfile(
+ GatherProfileResolver&& aResolve) {
+ mGatherProfileProgress = MakeRefPtr<ProgressLogger::SharedProgress>();
+ mGatherProfileProgress->SetProgress(ProportionValue{0.0},
+ "Received gather-profile request");
+
+ auto parameters = MakeRefPtr<GatherProfileThreadParameters>(
+ this, mGatherProfileProgress, std::move(aResolve));
+
+ // The GatherProfileThreadFunction thread function will cast its void*
+ // argument to already_AddRefed<GatherProfileThreadParameters>.
+ parameters.get()->AddRef();
+ PRThread* gatherProfileThread = PR_CreateThread(
+ PR_SYSTEM_THREAD, GatherProfileThreadFunction, parameters.get(),
+ PR_PRIORITY_NORMAL, PR_GLOBAL_THREAD, PR_UNJOINABLE_THREAD, 0);
+
+ if (!gatherProfileThread) {
+ // Failed to create and start worker thread, resolve with an empty profile.
+ mozilla::ipc::Shmem shmem;
+ if (AllocShmem(1, &shmem)) {
+ shmem.get<char>()[0] = '\0';
+ }
+ parameters->resolver(IPCProfileAndAdditionalInformation{shmem, Nothing()});
+ // And clean up.
+ parameters.get()->Release();
+ mGatherProfileProgress = nullptr;
+ }
+
+ return IPC_OK();
+}
+
+mozilla::ipc::IPCResult ProfilerChild::RecvGetGatherProfileProgress(
+ GetGatherProfileProgressResolver&& aResolve) {
+ if (mGatherProfileProgress) {
+ aResolve(GatherProfileProgress{
+ mGatherProfileProgress->Progress().ToUnderlyingType(),
+ nsCString(mGatherProfileProgress->LastLocation())});
+ } else {
+ aResolve(
+ GatherProfileProgress{ProportionValue::MakeInvalid().ToUnderlyingType(),
+ nsCString("No gather-profile in progress")});
+ }
+ return IPC_OK();
+}
+
+void ProfilerChild::ActorDestroy(ActorDestroyReason aActorDestroyReason) {
+ mDestroyed = true;
+}
+
+void ProfilerChild::Destroy() {
+ ResetChunkManager();
+ if (!mDestroyed) {
+ Close();
+ }
+}
+
+ProfileAndAdditionalInformation ProfilerChild::GrabShutdownProfile() {
+ LOG("GrabShutdownProfile");
+
+ UniquePtr<ProfilerCodeAddressService> service =
+ profiler_code_address_service_for_presymbolication();
+ FailureLatchSource failureLatch;
+ SpliceableChunkedJSONWriter writer{failureLatch};
+ writer.Start();
+ auto rv = profiler_stream_json_for_this_process(
+ writer, /* aSinceTime */ 0,
+ /* aIsShuttingDown */ true, service.get(), ProgressLogger{});
+ if (rv.isErr()) {
+ const char* failure = writer.GetFailure();
+ return ProfileAndAdditionalInformation(
+ nsPrintfCString("*Profile unavailable for pid %u%s%s",
+ unsigned(profiler_current_process_id().ToNumber()),
+ failure ? ", failure: " : "", failure ? failure : ""));
+ }
+
+ auto additionalInfo = rv.unwrap();
+
+ writer.StartArrayProperty("processes");
+ writer.EndArray();
+ writer.End();
+
+ const size_t len = writer.ChunkedWriteFunc().Length();
+ // This string and information are destined to be sent as a shutdown profile,
+ // which is limited by the maximum IPC message size.
+ // TODO: IPC to change to shmem (bug 1780330), raising this limit to
+ // JS::MaxStringLength.
+ if (len + additionalInfo.SizeOf() >=
+ size_t(IPC::Channel::kMaximumMessageSize)) {
+ return ProfileAndAdditionalInformation(
+ nsPrintfCString("*Profile from pid %u bigger (%zu) than IPC max (%zu)",
+ unsigned(profiler_current_process_id().ToNumber()), len,
+ size_t(IPC::Channel::kMaximumMessageSize)));
+ }
+
+ nsCString profileCString;
+ if (!profileCString.SetLength(len, fallible)) {
+ return ProfileAndAdditionalInformation(nsPrintfCString(
+ "*Could not allocate %zu bytes for profile from pid %u", len,
+ unsigned(profiler_current_process_id().ToNumber())));
+ }
+ MOZ_ASSERT(*(profileCString.Data() + len) == '\0',
+ "We expected a null at the end of the string buffer, to be "
+ "rewritten by CopyDataIntoLazilyAllocatedBuffer");
+
+ char* const profileBeginWriting = profileCString.BeginWriting();
+ if (!profileBeginWriting) {
+ return ProfileAndAdditionalInformation(
+ nsPrintfCString("*Could not write profile from pid %u",
+ unsigned(profiler_current_process_id().ToNumber())));
+ }
+
+ // Here, we have enough space reserved in `profileCString`, starting at
+ // `profileBeginWriting`, copy the JSON profile there.
+ if (!writer.ChunkedWriteFunc().CopyDataIntoLazilyAllocatedBuffer(
+ [&](size_t aBufferLen) -> char* {
+ MOZ_RELEASE_ASSERT(aBufferLen == len + 1);
+ return profileBeginWriting;
+ })) {
+ return ProfileAndAdditionalInformation(
+ nsPrintfCString("*Could not copy profile from pid %u",
+ unsigned(profiler_current_process_id().ToNumber())));
+ }
+ MOZ_ASSERT(*(profileCString.Data() + len) == '\0',
+ "We still expected a null at the end of the string buffer");
+
+ return ProfileAndAdditionalInformation{std::move(profileCString),
+ std::move(additionalInfo)};
+}
+
+} // namespace mozilla