From 36d22d82aa202bb199967e9512281e9a53db42c9 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 21:33:14 +0200 Subject: Adding upstream version 115.7.0esr. Signed-off-by: Daniel Baumann --- ipc/glue/ByteBufUtils.h | 56 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 56 insertions(+) create mode 100644 ipc/glue/ByteBufUtils.h (limited to 'ipc/glue/ByteBufUtils.h') diff --git a/ipc/glue/ByteBufUtils.h b/ipc/glue/ByteBufUtils.h new file mode 100644 index 0000000000..ba19864214 --- /dev/null +++ b/ipc/glue/ByteBufUtils.h @@ -0,0 +1,56 @@ +/* -*- 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/. */ + +/* A type that can be sent without needing to make a copy during + * serialization. In addition the receiver can take ownership of the + * data to avoid having to make an additional copy. */ + +#ifndef mozilla_ipc_ByteBufUtils_h +#define mozilla_ipc_ByteBufUtils_h + +#include "mozilla/ipc/ByteBuf.h" +#include "mozilla/CheckedInt.h" +#include "mozilla/mozalloc_oom.h" +#include "ipc/IPCMessageUtils.h" + +namespace IPC { + +template <> +struct ParamTraits { + typedef mozilla::ipc::ByteBuf paramType; + + // this is where we transfer the memory from the ByteBuf to IPDL, avoiding a + // copy + static void Write(MessageWriter* aWriter, paramType&& aParam) { + // We need to send the length as a 32-bit value, not a size_t, because on + // ARM64 Windows we end up with a 32-bit GMP process sending a ByteBuf to + // a 64-bit parent process. WriteBytesZeroCopy takes a uint32_t as an + // argument, so it would end up getting truncated anyways. See bug 1757534. + mozilla::CheckedInt length = aParam.mLen; + MOZ_RELEASE_ASSERT(length.isValid()); + WriteParam(aWriter, length.value()); + // hand over ownership of the buffer to the Message + aWriter->WriteBytesZeroCopy(aParam.mData, length.value(), aParam.mCapacity); + aParam.mData = nullptr; + aParam.mCapacity = 0; + aParam.mLen = 0; + } + + static bool Read(MessageReader* aReader, paramType* aResult) { + // We make a copy from the BufferList so that we get a contigous result. + uint32_t length; + if (!ReadParam(aReader, &length)) return false; + if (!aResult->Allocate(length)) { + mozalloc_handle_oom(length); + return false; + } + return aReader->ReadBytesInto(aResult->mData, length); + } +}; + +} // namespace IPC + +#endif // ifndef mozilla_ipc_ByteBufUtils_h -- cgit v1.2.3