gecko-dev/mozglue/dllservices/LoaderObserver.cpp

150 строки
4.0 KiB
C++

/* -*- 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 "LoaderObserver.h"
#include "mozilla/AutoProfilerLabel.h"
#include "mozilla/glue/WindowsUnicode.h"
#include "mozilla/StackWalk_windows.h"
namespace {
struct LoadContext {
LoadContext(mozilla::ProfilerLabel&& aLabel,
mozilla::UniquePtr<char[]>&& aDynamicStringStorage)
: mProfilerLabel(std::move(aLabel)),
mDynamicStringStorage(std::move(aDynamicStringStorage)) {}
mozilla::ProfilerLabel mProfilerLabel;
mozilla::UniquePtr<char[]> mDynamicStringStorage;
};
} // anonymous namespace
namespace mozilla {
extern glue::Win32SRWLock gDllServicesLock;
extern glue::detail::DllServicesBase* gDllServices;
namespace glue {
void LoaderObserver::OnBeginDllLoad(void** aContext,
PCUNICODE_STRING aRequestedDllName) {
MOZ_ASSERT(aContext);
if (IsProfilerPresent()) {
UniquePtr<char[]> utf8RequestedDllName(WideToUTF8(aRequestedDllName));
const char* dynamicString = utf8RequestedDllName.get();
*aContext = new LoadContext(
ProfilerLabelBegin("mozilla::glue::LoaderObserver::OnBeginDllLoad",
dynamicString, &aContext),
std::move(utf8RequestedDllName));
}
#ifdef _M_AMD64
// Prevent the stack walker from suspending this thread when LdrLoadDll
// holds the RtlLookupFunctionEntry lock.
SuppressStackWalking();
#endif
}
bool LoaderObserver::SubstituteForLSP(PCUNICODE_STRING aLSPLeafName,
PHANDLE aOutHandle) {
// Currently unsupported
return false;
}
void LoaderObserver::OnEndDllLoad(void* aContext, NTSTATUS aNtStatus,
ModuleLoadInfo&& aModuleLoadInfo) {
#ifdef _M_AMD64
DesuppressStackWalking();
#endif
UniquePtr<LoadContext> loadContext(static_cast<LoadContext*>(aContext));
if (loadContext && IsValidProfilerLabel(loadContext->mProfilerLabel)) {
ProfilerLabelEnd(loadContext->mProfilerLabel);
}
if (!NT_SUCCESS(aNtStatus) || !aModuleLoadInfo.WasMapped()) {
return;
}
{ // Scope for lock
AutoSharedLock lock(gDllServicesLock);
if (gDllServices) {
gDllServices->DispatchDllLoadNotification(std::move(aModuleLoadInfo));
return;
}
}
// No dll services, save for later
AutoExclusiveLock lock(mLock);
if (!mModuleLoads) {
mModuleLoads = new ModuleLoadInfoVec();
}
Unused << mModuleLoads->emplaceBack(
std::forward<ModuleLoadInfo>(aModuleLoadInfo));
}
void LoaderObserver::Forward(nt::LoaderObserver* aNext) {
MOZ_ASSERT_UNREACHABLE(
"This implementation does not forward to any more "
"nt::LoaderObserver objects");
}
void LoaderObserver::Forward(detail::DllServicesBase* aNext) {
MOZ_ASSERT(aNext);
if (!aNext) {
return;
}
ModuleLoadInfoVec* moduleLoads = nullptr;
{ // Scope for lock
AutoExclusiveLock lock(mLock);
moduleLoads = mModuleLoads;
mModuleLoads = nullptr;
}
if (!moduleLoads) {
return;
}
aNext->DispatchModuleLoadBacklogNotification(std::move(*moduleLoads));
delete moduleLoads;
}
void LoaderObserver::Clear() {
ModuleLoadInfoVec* moduleLoads = nullptr;
{ // Scope for lock
AutoExclusiveLock lock(mLock);
moduleLoads = mModuleLoads;
mModuleLoads = nullptr;
}
delete moduleLoads;
}
void LoaderObserver::OnForward(ModuleLoadInfoVec&& aInfo) {
AutoExclusiveLock lock(mLock);
if (!mModuleLoads) {
mModuleLoads = new ModuleLoadInfoVec();
}
MOZ_ASSERT(mModuleLoads->empty());
if (mModuleLoads->empty()) {
*mModuleLoads = std::move(aInfo);
} else {
// This should not happen, but we can handle it
for (auto&& item : aInfo) {
Unused << mModuleLoads->append(std::move(item));
}
}
}
} // namespace glue
} // namespace mozilla