/* -*- 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/. */
#ifndef __IPC_GLUE_IPCMESSAGEUTILS_H__
#define __IPC_GLUE_IPCMESSAGEUTILS_H__
#include "base/process_util.h"
#include "chrome/common/ipc_message_utils.h"
#include "mozilla/ArrayUtils.h"
#include "mozilla/Attributes.h"
#include "mozilla/DebugOnly.h"
#include "mozilla/dom/ipc/StructuredCloneData.h"
#include "mozilla/EnumSet.h"
#include "mozilla/EnumTypeTraits.h"
#include "mozilla/Maybe.h"
#include "mozilla/net/WebSocketFrame.h"
#include "mozilla/TimeStamp.h"
#ifdef XP_WIN
#include "mozilla/TimeStamp_windows.h"
#endif
#include "mozilla/TypeTraits.h"
#include "mozilla/IntegerTypeTraits.h"
#include <limits>
#include <stdint.h>
#include <type_traits>
#include "nsExceptionHandler.h"
#include "nsID.h"
#include "nsIWidget.h"
#include "nsMemory.h"
#include "nsString.h"
#include "nsTArray.h"
#include "js/StructuredClone.h"
#include "nsCSSPropertyID.h"
#ifdef _MSC_VER
#pragma warning(disable : 4800)
#endif
#if !defined(OS_POSIX)
// This condition must be kept in sync with the one in
// ipc_message_utils.h, but this dummy definition of
// base::FileDescriptor acts as a static assert that we only get one
// def or the other (or neither, in which case code using
// FileDescriptor fails to build)
namespace base {
struct FileDescriptor {};
} // namespace base
#endif
namespace mozilla {
// This is a cross-platform approximation to HANDLE, which we expect
// to be typedef'd to void* or thereabouts.
typedef uintptr_t WindowsHandle;
// XXX there are out of place and might be generally useful. Could
// move to nscore.h or something.
struct void_t {
bool operator==(const void_t&) const { return true; }
};
struct null_t {
bool operator==(const null_t&) const { return true; }
};
struct SerializedStructuredCloneBuffer final {
SerializedStructuredCloneBuffer()
: data(JS::StructuredCloneScope::Unassigned) {}
SerializedStructuredCloneBuffer(const SerializedStructuredCloneBuffer& aOther)
: SerializedStructuredCloneBuffer() {
*this = aOther;
}
SerializedStructuredCloneBuffer& operator=(
const SerializedStructuredCloneBuffer& aOther) {
data.Clear();
data.initScope(aOther.data.scope());
data.Append(aOther.data);
return *this;
}
bool operator==(const SerializedStructuredCloneBuffer& aOther) const {
// The copy assignment operator and the equality operator are
// needed by the IPDL generated code. We relied on the copy
// assignment operator at some places but we never use the
// equality operator.
return false;
}
JSStructuredCloneData data;
};
} // namespace mozilla
namespace IPC {
/**
* Maximum size, in bytes, of a single IPC message.
*/
static const uint32_t MAX_MESSAGE_SIZE = 65536;
/**
* Generic enum serializer.
*
* Consider using the specializations below, such as ContiguousEnumSerializer.
*
* This is a generic serializer for any enum type used in IPDL.
* Programmers can define ParamTraits<E> for enum type E by deriving
* EnumSerializer<E, MyEnumValidator> where MyEnumValidator is a struct
* that has to define a static IsLegalValue function returning whether
* a given value is a legal value of the enum type at hand.
*
* \sa https://developer.mozilla.org/en/IPDL/Type_Serialization
*/
template <typename E, typename EnumValidator>
struct EnumSerializer {
typedef E paramType;
typedef typename mozilla::UnsignedStdintTypeForSize<sizeof(paramType)>::Type
uintParamType;
static void Write(Message* aMsg, const paramType& aValue) {
MOZ_RELEASE_ASSERT(EnumValidator::IsLegalValue(aValue));
WriteParam(aMsg, uintParamType(aValue));
}
static bool Read(const Message* aMsg, PickleIterator* aIter,
paramType* aResult) {
uintParamType value;
if (!ReadParam(aMsg, aIter, &value)) {
CrashReporter::AnnotateCrashReport(
NS_LITERAL_CSTRING("IPCReadErrorReason"),
NS_LITERAL_CSTRING("Bad iter"));
return false;
} else if (!EnumValidator::IsLegalValue(paramType(value))) {
CrashReporter::AnnotateCrashReport(
NS_LITERAL_CSTRING("IPCReadErrorReason"),
NS_LITERAL_CSTRING("Illegal value"));
return false;
}
*aResult = paramType(value);
return true;
}
};
template <typename E, E MinLegal, E HighBound>
class ContiguousEnumValidator {
// Silence overzealous -Wtype-limits bug in GCC fixed in GCC 4.8:
// "comparison of unsigned expression >= 0 is always true"
// http://gcc.gnu.org/bugzilla/show_bug.cgi?id=11856
template <typename T>
static bool IsLessThanOrEqual(T a, T b) {
return a <= b;
}
public:
static bool IsLegalValue(E e) {
return IsLessThanOrEqual(MinLegal, e) && e < HighBound;
}
};
template <typename E, E MinLegal, E MaxLegal>
class ContiguousEnumValidatorInclusive {
// Silence overzealous -Wtype-limits bug in GCC fixed in GCC 4.8:
// "comparison of unsigned expression >= 0 is always true"
// http://gcc.gnu.org/bugzilla/show_bug.cgi?id=11856
template <typename T>
static bool IsLessThanOrEqual(T a, T b) {
return a <= b;
}
public:
static bool IsLegalValue(E e) {
return IsLessThanOrEqual(MinLegal, e) && e <= MaxLegal;
}
};
template <typename E, E AllBits>
struct BitFlagsEnumValidator {
static bool IsLegalValue(E e) { return (e & AllBits) == e; }
};
/**
* Specialization of EnumSerializer for enums with contiguous enum values.
*
* Provide two values: MinLegal, HighBound. An enum value x will be
* considered legal if MinLegal <= x < HighBound.
*
* For example, following is definition of serializer for enum type FOO.
* \code
* enum FOO { FOO_FIRST, FOO_SECOND, FOO_LAST, NUM_FOO };
*
* template <>
* struct ParamTraits<FOO>:
* public ContiguousEnumSerializer<FOO, FOO_FIRST, NUM_FOO> {};
* \endcode
* FOO_FIRST, FOO_SECOND, and FOO_LAST are valid value.
*/
template <typename E, E MinLegal, E HighBound>
struct ContiguousEnumSerializer
: EnumSerializer<E, ContiguousEnumValidator<E, MinLegal, HighBound>> {};
/**
* This is similar to ContiguousEnumSerializer, but the last template
* parameter is expected to be the highest legal value, rather than a
* sentinel value. This is intended to support enumerations that don't
* have sentinel values.
*/
template <typename E, E MinLegal, E MaxLegal>
struct ContiguousEnumSerializerInclusive
: EnumSerializer<E,
ContiguousEnumValidatorInclusive<E, MinLegal, MaxLegal>> {
};
/**
* Specialization of EnumSerializer for enums representing bit flags.
*
* Provide one value: AllBits. An enum value x will be
* considered legal if (x & AllBits) == x;
*
* Example:
* \code
* enum FOO {
* FOO_FIRST = 1 << 0,
* FOO_SECOND = 1 << 1,
* FOO_LAST = 1 << 2,
* ALL_BITS = (1 << 3) - 1
* };
*
* template <>
* struct ParamTraits<FOO>:
* public BitFlagsEnumSerializer<FOO, FOO::ALL_BITS> {};
* \endcode
*/
template <typename E, E AllBits>
struct BitFlagsEnumSerializer
: EnumSerializer<E, BitFlagsEnumValidator<E, AllBits>> {};
/**
* A helper class for serializing plain-old data (POD) structures.
* The memory representation of the structure is written to and read from
* the serialized stream directly, without individual processing of the
* structure's members.
*
* Derive ParamTraits<T> from PlainOldDataSerializer<T> if T is POD.
*
* Note: For POD structures with enumeration fields, this will not do
* validation of the enum values the way serializing the fields
* individually would. Prefer serializing the fields individually
* in such cases.
*/
template <typename T>
struct PlainOldDataSerializer {
// TODO: Once the mozilla::IsPod trait is in good enough shape (bug 900042),
// static_assert that mozilla::IsPod<T>::value is true.
typedef T paramType;
static void Write(Message* aMsg, const paramType& aParam) {
aMsg->WriteBytes(&aParam, sizeof(aParam));
}
static bool Read(const Message* aMsg, PickleIterator* aIter,
paramType* aResult) {
return aMsg->ReadBytesInto(aIter, aResult, sizeof(paramType));
}
};
/**
* A helper class for serializing empty structs. Since the struct is empty there
* is nothing to write, and a priori we know the result of the read.
*/
template <typename T>
struct EmptyStructSerializer {
typedef T paramType;
static void Write(Message* aMsg, const paramType& aParam) {}
static bool Read(const Message* aMsg, PickleIterator* aIter,
paramType* aResult) {
*aResult = {};
return true;
}
};
template <>
struct ParamTraits<int8_t> {
typedef int8_t paramType;
static void Write(Message* aMsg, const paramType& aParam) {
aMsg->WriteBytes(&aParam, sizeof(aParam));
}
static bool Read(const Message* aMsg, PickleIterator* aIter,
paramType* aResult) {
return aMsg->ReadBytesInto(aIter, aResult, sizeof(*aResult));
}
static void Log(const paramType& aParam, std::wstring* aLog) {
// Use 0xff to avoid sign extension.
aLog->append(StringPrintf(L"0x%02x", aParam & 0xff));
}
};
template <>
struct ParamTraits<uint8_t> {
typedef uint8_t paramType;
static void Write(Message* aMsg, const paramType& aParam) {
aMsg->WriteBytes(&aParam, sizeof(aParam));
}
static bool Read(const Message* aMsg, PickleIterator* aIter,
paramType* aResult) {
return aMsg->ReadBytesInto(aIter, aResult, sizeof(*aResult));
}
static void Log(const paramType& aParam, std::wstring* aLog) {
aLog->append(StringPrintf(L"0x%02x", aParam));
}
};
#if !defined(OS_POSIX)
// See above re: keeping definitions in sync
template <>
struct ParamTraits<base::FileDescriptor> {
typedef base::FileDescriptor paramType;
static void Write(Message* aMsg, const paramType& aParam) {
MOZ_CRASH("FileDescriptor isn't meaningful on this platform");
}
static bool Read(const Message* aMsg, PickleIterator* aIter,
paramType* aResult) {
MOZ_CRASH("FileDescriptor isn't meaningful on this platform");
return false;
}
};
#endif // !defined(OS_POSIX)
template <>
struct ParamTraits<nsACString> {
typedef nsACString paramType;
static void Write(Message* aMsg, const paramType& aParam) {
bool isVoid = aParam.IsVoid();
aMsg->WriteBool(isVoid);
if (isVoid)
// represents a nullptr pointer
return;
uint32_t length = aParam.Length();
WriteParam(aMsg, length);
aMsg->WriteBytes(aParam.BeginReading(), length);
}
static bool Read(const Message* aMsg, PickleIterator* aIter,
paramType* aResult) {
bool isVoid;
if (!aMsg->ReadBool(aIter, &isVoid)) return false;
if (isVoid) {
aResult->SetIsVoid(true);
return true;
}
uint32_t length;
if (!ReadParam(aMsg, aIter, &length)) {
return false;
}
aResult->SetLength(length);
return aMsg->ReadBytesInto(aIter, aResult->BeginWriting(), length);
}
static void Log(const paramType& aParam, std::wstring* aLog) {
if (aParam.IsVoid())
aLog->append(L"(NULL)");
else
aLog->append(UTF8ToWide(aParam.BeginReading()));
}
};
template <>
struct ParamTraits<nsAString> {
typedef nsAString paramType;
static void Write(Message* aMsg, const paramType& aParam) {
bool isVoid = aParam.IsVoid();
aMsg->WriteBool(isVoid);
if (isVoid)
// represents a nullptr pointer
return;
uint32_t length = aParam.Length();
WriteParam(aMsg, length);
aMsg->WriteBytes(aParam.BeginReading(), length * sizeof(char16_t));
}
static bool Read(const Message* aMsg, PickleIterator* aIter,
paramType* aResult) {
bool isVoid;
if (!aMsg->ReadBool(aIter, &isVoid)) return false;
if (isVoid) {
aResult->SetIsVoid(true);
return true;
}
uint32_t length;
if (!ReadParam(aMsg, aIter, &length)) {
return false;
}
aResult->SetLength(length);
mozilla::CheckedInt<uint32_t> byteLength =
mozilla::CheckedInt<uint32_t>(length) * sizeof(char16_t);
if (!byteLength.isValid()) {
return false;
}
return aMsg->ReadBytesInto(aIter, aResult->BeginWriting(),
byteLength.value());
}
static void Log(const paramType& aParam, std::wstring* aLog) {
if (aParam.IsVoid())
aLog->append(L"(NULL)");
else {
#ifdef WCHAR_T_IS_UTF16
aLog->append(reinterpret_cast<const wchar_t*>(aParam.BeginReading()));
#else
uint32_t length = aParam.Length();
for (uint32_t index = 0; index < length; index++) {
aLog->push_back(std::wstring::value_type(aParam[index]));
}
#endif
}
}
};
template <>
struct ParamTraits<nsCString> : ParamTraits<nsACString> {
typedef nsCString paramType;
};
template <>
struct ParamTraits<nsLiteralCString> : ParamTraits<nsACString> {
typedef nsLiteralCString paramType;
};
#ifdef MOZILLA_INTERNAL_API
template <>
struct ParamTraits<nsAutoCString> : ParamTraits<nsCString> {
typedef nsAutoCString paramType;
};
#endif // MOZILLA_INTERNAL_API
template <>
struct ParamTraits<nsString> : ParamTraits<nsAString> {
typedef nsString paramType;
};
template <>
struct ParamTraits<nsLiteralString> : ParamTraits<nsAString> {
typedef nsLiteralString paramType;
};
template <>
struct ParamTraits<nsDependentSubstring> : ParamTraits<nsAString> {
typedef nsDependentSubstring paramType;
};
template <>
struct ParamTraits<nsDependentCSubstring> : ParamTraits<nsACString> {
typedef nsDependentCSubstring paramType;
};
#ifdef MOZILLA_INTERNAL_API
template <>
struct ParamTraits<nsAutoString> : ParamTraits<nsString> {
typedef nsAutoString paramType;
};
#endif // MOZILLA_INTERNAL_API
// Pickle::ReadBytes and ::WriteBytes take the length in ints, so we must
// ensure there is no overflow. This returns |false| if it would overflow.
// Otherwise, it returns |true| and places the byte length in |aByteLength|.
bool ByteLengthIsValid(uint32_t aNumElements, size_t aElementSize,
int* aByteLength);
// Note: IPDL will sometimes codegen specialized implementations of
// nsTArray serialization and deserialization code in
// implementSpecialArrayPickling(). This is needed when ParamTraits<E>
// is not defined.
template <typename E>
struct ParamTraits<nsTArray<E>> {
typedef nsTArray<E> paramType;
// We write arrays of integer or floating-point data using a single pickling
// call, rather than writing each element individually. We deliberately do
// not use mozilla::IsPod here because it is perfectly reasonable to have
// a data structure T for which IsPod<T>::value is true, yet also have a
// ParamTraits<T> specialization.
static const bool sUseWriteBytes =
(mozilla::IsIntegral<E>::value || mozilla::IsFloatingPoint<E>::value);
static void Write(Message* aMsg, const paramType& aParam) {
uint32_t length = aParam.Length();
WriteParam(aMsg, length);
if (sUseWriteBytes) {
int pickledLength = 0;
MOZ_RELEASE_ASSERT(ByteLengthIsValid(length, sizeof(E), &pickledLength));
aMsg->WriteBytes(aParam.Elements(), pickledLength);
} else {
const E* elems = aParam.Elements();
for (uint32_t index = 0; index < length; index++) {
WriteParam(aMsg, elems[index]);
}
}
}
// This method uses infallible allocation so that an OOM failure will
// show up as an OOM crash rather than an IPC FatalError.
static bool Read(const Message* aMsg, PickleIterator* aIter,
paramType* aResult) {
uint32_t length;
if (!ReadParam(aMsg, aIter, &length)) {
return false;
}
if (sUseWriteBytes) {
int pickledLength = 0;
if (!ByteLengthIsValid(length, sizeof(E), &pickledLength)) {
return false;
}
E* elements = aResult->AppendElements(length);
return aMsg->ReadBytesInto(aIter, elements, pickledLength);
} else {
aResult->SetCapacity(length);
for (uint32_t index = 0; index < length; index++) {
E* element = aResult->AppendElement();
if (!ReadParam(aMsg, aIter, element)) {
return false;
}
}
return true;
}
}
static void Log(const paramType& aParam, std::wstring* aLog) {
for (uint32_t index = 0; index < aParam.Length(); index++) {
if (index) {
aLog->append(L" ");
}
LogParam(aParam[index], aLog);
}
}
};
template <typename E>
struct ParamTraits<FallibleTArray<E>> {
typedef FallibleTArray<E> paramType;
static void Write(Message* aMsg, const paramType& aParam) {
WriteParam(aMsg, static_cast<const nsTArray<E>&>(aParam));
}
// Deserialize the array infallibly, but return a FallibleTArray.
static bool Read(const Message* aMsg, PickleIterator* aIter,
paramType* aResult) {
nsTArray<E> temp;
if (!ReadParam(aMsg, aIter, &temp)) return false;
aResult->SwapElements(temp);
return true;
}
static void Log(const paramType& aParam, std::wstring* aLog) {
LogParam(static_cast<const nsTArray<E>&>(aParam), aLog);
}
};
template <typename E, size_t N>
struct ParamTraits<AutoTArray<E, N>> : ParamTraits<nsTArray<E>> {
typedef AutoTArray<E, N> paramType;
};
template <>
struct ParamTraits<float> {
typedef float paramType;
static void Write(Message* aMsg, const paramType& aParam) {
aMsg->WriteBytes(&aParam, sizeof(paramType));
}
static bool Read(const Message* aMsg, PickleIterator* aIter,
paramType* aResult) {
return aMsg->ReadBytesInto(aIter, aResult, sizeof(*aResult));
}
static void Log(const paramType& aParam, std::wstring* aLog) {
aLog->append(StringPrintf(L"%g", aParam));
}
};
template <>
struct ParamTraits<nsCSSPropertyID>
: public ContiguousEnumSerializer<nsCSSPropertyID, eCSSProperty_UNKNOWN,
eCSSProperty_COUNT> {};
template <>
struct ParamTraits<mozilla::void_t> {
typedef mozilla::void_t paramType;
static void Write(Message* aMsg, const paramType& aParam) {}
static bool Read(const Message* aMsg, PickleIterator* aIter,
paramType* aResult) {
*aResult = paramType();
return true;
}
};
template <>
struct ParamTraits<mozilla::null_t> {
typedef mozilla::null_t paramType;
static void Write(Message* aMsg, const paramType& aParam) {}
static bool Read(const Message* aMsg, PickleIterator* aIter,
paramType* aResult) {
*aResult = paramType();
return true;
}
};
template <>
struct ParamTraits<nsID> {
typedef nsID paramType;
static void Write(Message* aMsg, const paramType& aParam) {
WriteParam(aMsg, aParam.m0);
WriteParam(aMsg, aParam.m1);
WriteParam(aMsg, aParam.m2);
for (unsigned int i = 0; i < mozilla::ArrayLength(aParam.m3); i++) {
WriteParam(aMsg, aParam.m3[i]);
}
}
static bool Read(const Message* aMsg, PickleIterator* aIter,
paramType* aResult) {
if (!ReadParam(aMsg, aIter, &(aResult->m0)) ||
!ReadParam(aMsg, aIter, &(aResult->m1)) ||
!ReadParam(aMsg, aIter, &(aResult->m2)))
return false;
for (unsigned int i = 0; i < mozilla::ArrayLength(aResult->m3); i++)
if (!ReadParam(aMsg, aIter, &(aResult->m3[i]))) return false;
return true;
}
static void Log(const paramType& aParam, std::wstring* aLog) {
aLog->append(L"{");
aLog->append(
StringPrintf(L"%8.8X-%4.4X-%4.4X-", aParam.m0, aParam.m1, aParam.m2));
for (unsigned int i = 0; i < mozilla::ArrayLength(aParam.m3); i++)
aLog->append(StringPrintf(L"%2.2X", aParam.m3[i]));
aLog->append(L"}");
}
};
template <>
struct ParamTraits<mozilla::TimeDuration> {
typedef mozilla::TimeDuration paramType;
static void Write(Message* aMsg, const paramType& aParam) {
WriteParam(aMsg, aParam.mValue);
}
static bool Read(const Message* aMsg, PickleIterator* aIter,
paramType* aResult) {
return ReadParam(aMsg, aIter, &aResult->mValue);
};
};
template <>
struct ParamTraits<mozilla::TimeStamp> {
typedef mozilla::TimeStamp paramType;
static void Write(Message* aMsg, const paramType& aParam) {
WriteParam(aMsg, aParam.mValue);
}
static bool Read(const Message* aMsg, PickleIterator* aIter,
paramType* aResult) {
return ReadParam(aMsg, aIter, &aResult->mValue);
};
};
#ifdef XP_WIN
template <>
struct ParamTraits<mozilla::TimeStampValue> {
typedef mozilla::TimeStampValue paramType;
static void Write(Message* aMsg, const paramType& aParam) {
WriteParam(aMsg, aParam.mGTC);
WriteParam(aMsg, aParam.mQPC);
WriteParam(aMsg, aParam.mHasQPC);
WriteParam(aMsg, aParam.mIsNull);
}
static bool Read(const Message* aMsg, PickleIterator* aIter,
paramType* aResult) {
return (ReadParam(aMsg, aIter, &aResult->mGTC) &&
ReadParam(aMsg, aIter, &aResult->mQPC) &&
ReadParam(aMsg, aIter, &aResult->mHasQPC) &&
ReadParam(aMsg, aIter, &aResult->mIsNull));
}
};
#endif
template <>
struct ParamTraits<mozilla::dom::ipc::StructuredCloneData> {
typedef mozilla::dom::ipc::StructuredCloneData paramType;
static void Write(Message* aMsg, const paramType& aParam) {
aParam.WriteIPCParams(aMsg);
}
static bool Read(const Message* aMsg, PickleIterator* aIter,
paramType* aResult) {
return aResult->ReadIPCParams(aMsg, aIter);
}
static void Log(const paramType& aParam, std::wstring* aLog) {
LogParam(aParam.DataLength(), aLog);
}
};
template <>
struct ParamTraits<mozilla::net::WebSocketFrameData> {
typedef mozilla::net::WebSocketFrameData paramType;
static void Write(Message* aMsg, const paramType& aParam) {
aParam.WriteIPCParams(aMsg);
}
static bool Read(const Message* aMsg, PickleIterator* aIter,
paramType* aResult) {
return aResult->ReadIPCParams(aMsg, aIter);
}
};
template <>
struct ParamTraits<JSStructuredCloneData> {
typedef JSStructuredCloneData paramType;
static void Write(Message* aMsg, const paramType& aParam) {
MOZ_ASSERT(!(aParam.Size() % sizeof(uint64_t)));
WriteParam(aMsg, aParam.Size());
aParam.ForEachDataChunk([&](const char* aData, size_t aSize) {
return aMsg->WriteBytes(aData, aSize, sizeof(uint64_t));
});
}
static bool Read(const Message* aMsg, PickleIterator* aIter,
paramType* aResult) {
size_t length = 0;
if (!ReadParam(aMsg, aIter, &length)) {
return false;
}
MOZ_ASSERT(!(length % sizeof(uint64_t)));
mozilla::BufferList<InfallibleAllocPolicy> buffers(0, 0, 4096);
// Borrowing is not suitable to use for IPC to hand out data
// because we often want to store the data somewhere for
// processing after IPC has released the underlying buffers. One
// case is PContentChild::SendGetXPCOMProcessAttributes. We can't
// return a borrowed buffer because the out param outlives the
// IPDL callback.
if (length &&
!aMsg->ExtractBuffers(aIter, length, &buffers, sizeof(uint64_t))) {
return false;
}
bool success;
mozilla::BufferList<js::SystemAllocPolicy> out =
buffers.MoveFallible<js::SystemAllocPolicy>(&success);
if (!success) {
return false;
}
*aResult = JSStructuredCloneData(
Move(out), JS::StructuredCloneScope::DifferentProcess);
return true;
}
};
template <>
struct ParamTraits<mozilla::SerializedStructuredCloneBuffer> {
typedef mozilla::SerializedStructuredCloneBuffer paramType;
static void Write(Message* aMsg, const paramType& aParam) {
WriteParam(aMsg, aParam.data);
}
static bool Read(const Message* aMsg, PickleIterator* aIter,
paramType* aResult) {
return ReadParam(aMsg, aIter, &aResult->data);
}
static void Log(const paramType& aParam, std::wstring* aLog) {
LogParam(aParam.data.Size(), aLog);
}
};
template <>
struct ParamTraits<nsIWidget::TouchPointerState>
: public BitFlagsEnumSerializer<nsIWidget::TouchPointerState,
nsIWidget::TouchPointerState::ALL_BITS> {};
template <class T>
struct ParamTraits<mozilla::Maybe<T>> {
typedef mozilla::Maybe<T> paramType;
static void Write(Message* msg, const paramType& param) {
if (param.isSome()) {
WriteParam(msg, true);
WriteParam(msg, param.value());
} else {
WriteParam(msg, false);
}
}
static bool Read(const Message* msg, PickleIterator* iter,
paramType* result) {
bool isSome;
if (!ReadParam(msg, iter, &isSome)) {
return false;
}
if (isSome) {
T tmp;
if (!ReadParam(msg, iter, &tmp)) {
return false;
}
*result = mozilla::Some(mozilla::Move(tmp));
} else {
*result = mozilla::Nothing();
}
return true;
}
};
template <typename T>
struct ParamTraits<mozilla::EnumSet<T>> {
typedef mozilla::EnumSet<T> paramType;
typedef typename mozilla::EnumSet<T>::serializedType serializedType;
static void Write(Message* msg, const paramType& param) {
MOZ_RELEASE_ASSERT(IsLegalValue(param.serialize()));
WriteParam(msg, param.serialize());
}
static bool Read(const Message* msg, PickleIterator* iter,
paramType* result) {
serializedType tmp;
if (ReadParam(msg, iter, &tmp)) {
if (IsLegalValue(tmp)) {
result->deserialize(tmp);
return true;
}
}
return false;
}
static constexpr serializedType AllEnumBits() {
return ~serializedType(0) >> (std::numeric_limits<serializedType>::digits -
(mozilla::MaxEnumValue<T>::value + 1));
}
static constexpr bool IsLegalValue(const serializedType value) {
static_assert(mozilla::MaxEnumValue<T>::value <
std::numeric_limits<serializedType>::digits,
"Enum max value is not in the range!");
static_assert(
std::is_unsigned<decltype(mozilla::MaxEnumValue<T>::value)>::value,
"Type of MaxEnumValue<T>::value specialization should be unsigned!");
return (value & AllEnumBits()) == value;
}
};
template <class... Ts>
struct ParamTraits<mozilla::Variant<Ts...>> {
typedef mozilla::Variant<Ts...> paramType;
using Tag = typename mozilla::detail::VariantTag<Ts...>::Type;
struct VariantWriter {
Message* msg;
template <class T>
void match(const T& t) {
WriteParam(msg, t);
}
};
static void Write(Message* msg, const paramType& param) {
WriteParam(msg, param.tag);
param.match(VariantWriter{msg});
}
// Because VariantReader is a nested struct, we need the dummy template
// parameter to avoid making VariantReader<0> an explicit specialization,
// which is not allowed for a nested class template
template <size_t N, typename dummy = void>
struct VariantReader {
using Next = VariantReader<N - 1>;
static bool Read(const Message* msg, PickleIterator* iter, Tag tag,
paramType* result) {
// Since the VariantReader specializations start at N , we need to
// subtract one to look at N - 1, the first valid tag. This means our
// comparisons are off by 1. If we get to N = 0 then we have failed to
// find a match to the tag.
if (tag == N - 1) {
// Recall, even though the template parameter is N, we are
// actually interested in the N - 1 tag.
typename mozilla::detail::Nth<N - 1, Ts...>::Type val;
if (ReadParam(msg, iter, &val)) {
*result = mozilla::AsVariant(val);
return true;
}
return false;
} else {
return Next::Read(msg, iter, tag, result);
}
}
}; // VariantReader<N>
// Since we are conditioning on tag = N - 1 in the preceding specialization,
// if we get to `VariantReader<0, dummy>` we have failed to find
// a matching tag.
template <typename dummy>
struct VariantReader<0, dummy> {
static bool Read(const Message* msg, PickleIterator* iter, Tag tag,
paramType* result) {
return false;
}
};
static bool Read(const Message* msg, PickleIterator* iter,
paramType* result) {
Tag tag;
if (ReadParam(msg, iter, &tag)) {
return VariantReader<sizeof...(Ts)>::Read(msg, iter, tag, result);
}
return false;
}
};
template <typename T>
struct ParamTraits<mozilla::dom::Optional<T>> {
typedef mozilla::dom::Optional<T> paramType;
static void Write(Message* aMsg, const paramType& aParam) {
if (aParam.WasPassed()) {
WriteParam(aMsg, true);
WriteParam(aMsg, aParam.Value());
return;
}
WriteParam(aMsg, false);
}
static bool Read(const Message* aMsg, PickleIterator* aIter,
paramType* aResult) {
bool wasPassed = false;
if (!ReadParam(aMsg, aIter, &wasPassed)) {
return false;
}
aResult->Reset();
if (wasPassed) {
if (!ReadParam(aMsg, aIter, &aResult->Construct())) {
return false;
}
}
return true;
}
};
} /* namespace IPC */
#endif /* __IPC_GLUE_IPCMESSAGEUTILS_H__ */