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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 19:33:14 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 19:33:14 +0000 |
commit | 36d22d82aa202bb199967e9512281e9a53db42c9 (patch) | |
tree | 105e8c98ddea1c1e4784a60a5a6410fa416be2de /js/xpconnect/src/XPCSelfHostedShmem.cpp | |
parent | Initial commit. (diff) | |
download | firefox-esr-upstream.tar.xz firefox-esr-upstream.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-- | js/xpconnect/src/XPCSelfHostedShmem.cpp | 116 |
1 files changed, 116 insertions, 0 deletions
diff --git a/js/xpconnect/src/XPCSelfHostedShmem.cpp b/js/xpconnect/src/XPCSelfHostedShmem.cpp new file mode 100644 index 0000000000..e5c8578ccd --- /dev/null +++ b/js/xpconnect/src/XPCSelfHostedShmem.cpp @@ -0,0 +1,116 @@ +/* -*- 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 "XPCSelfHostedShmem.h" +#include "xpcprivate.h" + +// static +mozilla::StaticRefPtr<xpc::SelfHostedShmem> + xpc::SelfHostedShmem::sSelfHostedXdr; + +NS_IMPL_ISUPPORTS(xpc::SelfHostedShmem, nsIMemoryReporter) + +// static +xpc::SelfHostedShmem& xpc::SelfHostedShmem::GetSingleton() { + MOZ_ASSERT_IF(!sSelfHostedXdr, NS_IsMainThread()); + + if (!sSelfHostedXdr) { + sSelfHostedXdr = new SelfHostedShmem; + } + + return *sSelfHostedXdr; +} + +void xpc::SelfHostedShmem::InitMemoryReporter() { + mozilla::RegisterWeakMemoryReporter(this); +} + +// static +void xpc::SelfHostedShmem::Shutdown() { + MOZ_ASSERT(NS_IsMainThread()); + // NOTE: We cannot call UnregisterWeakMemoryReporter(sSelfHostedXdr) as the + // service is shutdown at the time this call is made. In any cases, this would + // already be done when the memory reporter got destroyed. + sSelfHostedXdr = nullptr; +} + +void xpc::SelfHostedShmem::InitFromParent(ContentType aXdr) { + MOZ_ASSERT(XRE_IsParentProcess()); + MOZ_ASSERT(NS_IsMainThread()); + MOZ_ASSERT(!mLen, "Shouldn't call this more than once"); + + size_t len = aXdr.Length(); + auto shm = mozilla::MakeUnique<base::SharedMemory>(); + if (NS_WARN_IF(!shm->CreateFreezeable(len))) { + return; + } + + if (NS_WARN_IF(!shm->Map(len))) { + return; + } + + void* address = shm->memory(); + memcpy(address, aXdr.Elements(), aXdr.LengthBytes()); + + base::SharedMemory roCopy; + if (NS_WARN_IF(!shm->ReadOnlyCopy(&roCopy))) { + return; + } + + mMem = std::move(shm); + mHandle = roCopy.TakeHandle(); + mLen = len; +} + +bool xpc::SelfHostedShmem::InitFromChild(::base::SharedMemoryHandle aHandle, + size_t aLen) { + MOZ_ASSERT(!XRE_IsParentProcess()); + MOZ_ASSERT(NS_IsMainThread()); + MOZ_ASSERT(!mLen, "Shouldn't call this more than once"); + + auto shm = mozilla::MakeUnique<base::SharedMemory>(); + if (NS_WARN_IF(!shm->SetHandle(std::move(aHandle), /* read_only */ true))) { + return false; + } + + if (NS_WARN_IF(!shm->Map(aLen))) { + return false; + } + + // Note: mHandle remains empty, as content processes are not spawning more + // content processes. + mMem = std::move(shm); + mLen = aLen; + return true; +} + +xpc::SelfHostedShmem::ContentType xpc::SelfHostedShmem::Content() const { + if (!mMem) { + MOZ_ASSERT(mLen == 0); + return ContentType(); + } + return ContentType(reinterpret_cast<uint8_t*>(mMem->memory()), mLen); +} + +const mozilla::UniqueFileHandle& xpc::SelfHostedShmem::Handle() const { + return mHandle; +} + +NS_IMETHODIMP +xpc::SelfHostedShmem::CollectReports(nsIHandleReportCallback* aHandleReport, + nsISupports* aData, bool aAnonymize) { + // If this is the parent process, then we have a handle and this instance owns + // the data and shares it with other processes, otherwise this is shared data. + if (XRE_IsParentProcess()) { + // This does not exactly report the amount of data mapped by the system, + // but the space requested when creating the handle. + MOZ_COLLECT_REPORT("explicit/js-non-window/shared-memory/self-hosted-xdr", + KIND_NONHEAP, UNITS_BYTES, mLen, + "Memory used to initialize the JS engine with the " + "self-hosted code encoded by the parent process."); + } + return NS_OK; +} |