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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: sw=2 ts=4 et :
*/
/* 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
#ifndef _QUEUEPARAMTRAITS_H_
#define _QUEUEPARAMTRAITS_H_ 1
#include "ipc/EnumSerializer.h"
#include "mozilla/gfx/2D.h"
#include "mozilla/Assertions.h"
#include "mozilla/IntegerRange.h"
#include "mozilla/ipc/ProtocolUtils.h"
#include "mozilla/ipc/SharedMemory.h"
#include "mozilla/Logging.h"
#include "mozilla/TimeStamp.h"
#include "nsExceptionHandler.h"
#include "nsString.h"
#include "WebGLTypes.h"
#include <optional>
namespace mozilla::webgl {
template <typename T>
struct RemoveCVR {
using Type =
typename std::remove_reference<typename std::remove_cv<T>::type>::type;
};
/**
* QueueParamTraits provide the user with a way to implement PCQ argument
* (de)serialization. It uses a PcqView, which permits the system to
* abandon all changes to the underlying PCQ if any operation fails.
*
* The transactional nature of PCQ operations make the ideal behavior a bit
* complex. Since the PCQ has a fixed amount of memory available to it,
* TryInsert operations operations are expected to sometimes fail and be
* re-issued later. We want these failures to be inexpensive. The same
* goes for TryRemove, which fails when there isn't enough data in
* the queue yet for them to complete.
*
* Their expected interface is:
*
* template<> struct QueueParamTraits<typename RemoveCVR<Arg>::Type> {
* // Write data from aArg into the PCQ.
* static QueueStatus Write(ProducerView& aProducerView, const Arg& aArg)
* {...};
*
* // Read data from the PCQ into aArg, or just skip the data if aArg is null.
* static QueueStatus Read(ConsumerView& aConsumerView, Arg* aArg) {...}
* };
*/
template <typename Arg>
struct QueueParamTraits; // Todo: s/QueueParamTraits/SizedParamTraits/
template <typename T>
inline Range<T> AsRange(T* const begin, T* const end) {
const auto size = MaybeAs<size_t>(end - begin);
MOZ_RELEASE_ASSERT(size);
return {begin, *size};
}
// -
// BytesAlwaysValidT
template <class T>
struct BytesAlwaysValidT {
using non_cv = typename std::remove_cv<T>::type;
static constexpr bool value =
std::is_arithmetic<T>::value && !std::is_same<non_cv, bool>::value;
};
static_assert(BytesAlwaysValidT<float>::value);
static_assert(!BytesAlwaysValidT<bool>::value);
static_assert(!BytesAlwaysValidT<const bool>::value);
static_assert(!BytesAlwaysValidT<int*>::value);
static_assert(BytesAlwaysValidT<intptr_t>::value);
template <class T, size_t N>
struct BytesAlwaysValidT<std::array<T, N>> {
static constexpr bool value = BytesAlwaysValidT<T>::value;
};
static_assert(BytesAlwaysValidT<std::array<int, 4>>::value);
static_assert(!BytesAlwaysValidT<std::array<bool, 4>>::value);
template <class T, size_t N>
struct BytesAlwaysValidT<T[N]> {
static constexpr bool value = BytesAlwaysValidT<T>::value;
};
static_assert(BytesAlwaysValidT<int[4]>::value);
static_assert(!BytesAlwaysValidT<bool[4]>::value);
// -
template <>
struct BytesAlwaysValidT<webgl::UniformDataVal> {
static constexpr bool value = true;
};
template <>
struct BytesAlwaysValidT<const webgl::UniformDataVal> {
static constexpr bool value = true;
};
// -
/**
* Used to give QueueParamTraits a way to write to the Producer without
* actually altering it, in case the transaction fails.
* THis object maintains the error state of the transaction and
* discards commands issued after an error is encountered.
*/
template <typename _Producer>
class ProducerView {
public:
using Producer = _Producer;
explicit ProducerView(Producer* aProducer) : mProducer(aProducer) {}
template <typename T>
bool WriteFromRange(const Range<const T>& src) {
static_assert(BytesAlwaysValidT<T>::value);
if (MOZ_LIKELY(mOk)) {
mOk &= mProducer->WriteFromRange(src);
}
return mOk;
}
/**
* Copy bytes from aBuffer to the producer if there is enough room.
* aBufferSize must not be 0.
*/
template <typename T>
inline bool Write(const T* begin, const T* end) {
MOZ_RELEASE_ASSERT(begin <= end);
return WriteFromRange(AsRange(begin, end));
}
/**
* Serialize aArg using Arg's QueueParamTraits.
*/
template <typename Arg>
bool WriteParam(const Arg& aArg) {
return mozilla::webgl::QueueParamTraits<
typename RemoveCVR<Arg>::Type>::Write(*this, aArg);
}
bool Ok() const { return mOk; }
private:
Producer* const mProducer;
bool mOk = true;
};
/**
* Used to give QueueParamTraits a way to read from the Consumer without
* actually altering it, in case the transaction fails.
*/
template <typename _Consumer>
class ConsumerView {
public:
using Consumer = _Consumer;
explicit ConsumerView(Consumer* aConsumer) : mConsumer(aConsumer) {}
/**
* Read bytes from the consumer if there is enough data. aBuffer may
* be null (in which case the data is skipped)
*/
template <typename T>
inline bool Read(T* const destBegin, T* const destEnd) {
MOZ_ASSERT(destBegin);
MOZ_RELEASE_ASSERT(destBegin <= destEnd);
const auto dest = AsRange(destBegin, destEnd);
const auto view = ReadRange<T>(dest.length());
if (MOZ_LIKELY(view)) {
const auto byteSize = ByteSize(dest);
if (MOZ_LIKELY(byteSize)) {
memcpy(dest.begin().get(), view->begin().get(), byteSize);
}
}
return mOk;
}
/// Return a view wrapping the shmem.
template <typename T>
inline Maybe<Range<const T>> ReadRange(const size_t elemCount) {
static_assert(BytesAlwaysValidT<T>::value);
if (MOZ_UNLIKELY(!mOk)) return {};
const auto view = mConsumer->template ReadRange<T>(elemCount);
mOk &= bool(view);
return view;
}
/**
* Deserialize aArg using Arg's QueueParamTraits.
* If the return value is not Success then aArg is not changed.
*/
template <typename Arg>
bool ReadParam(Arg* aArg) {
MOZ_ASSERT(aArg);
return mozilla::webgl::QueueParamTraits<std::remove_cv_t<Arg>>::Read(*this,
aArg);
}
bool Ok() const { return mOk; }
private:
Consumer* const mConsumer;
bool mOk = true;
};
// -
template <typename Arg>
struct QueueParamTraits {
template <typename ProducerView>
static bool Write(ProducerView& aProducerView, const Arg& aArg) {
static_assert(BytesAlwaysValidT<Arg>::value,
"No QueueParamTraits specialization was found for this type "
"and it does not satisfy BytesAlwaysValid.");
// Write self as binary
const auto pArg = &aArg;
return aProducerView.Write(pArg, pArg + 1);
}
template <typename ConsumerView>
static bool Read(ConsumerView& aConsumerView, Arg* aArg) {
static_assert(BytesAlwaysValidT<Arg>::value,
"No QueueParamTraits specialization was found for this type "
"and it does not satisfy BytesAlwaysValid.");
// Read self as binary
return aConsumerView.Read(aArg, aArg + 1);
}
};
// ---------------------------------------------------------------
template <>
struct QueueParamTraits<bool> {
using ParamType = bool;
template <typename U>
static auto Write(ProducerView<U>& aProducerView, const ParamType& aArg) {
uint8_t temp = aArg ? 1 : 0;
return aProducerView.WriteParam(temp);
}
template <typename U>
static auto Read(ConsumerView<U>& aConsumerView, ParamType* aArg) {
uint8_t temp;
if (aConsumerView.ReadParam(&temp)) {
MOZ_ASSERT(temp == 1 || temp == 0);
*aArg = temp ? true : false;
}
return aConsumerView.Ok();
}
};
// ---------------------------------------------------------------
template <class T>
struct QueueParamTraits_IsEnumCase {
template <typename ProducerView>
static bool Write(ProducerView& aProducerView, const T& aArg) {
MOZ_ASSERT(IsEnumCase(aArg));
const auto shadow = static_cast<std::underlying_type_t<T>>(aArg);
aProducerView.WriteParam(shadow);
return true;
}
template <typename ConsumerView>
static bool Read(ConsumerView& aConsumerView, T* aArg) {
auto shadow = std::underlying_type_t<T>{};
aConsumerView.ReadParam(&shadow);
const auto e = AsEnumCase<T>(shadow);
if (!e) return false;
*aArg = *e;
return true;
}
};
// ---------------------------------------------------------------
// We guarantee our robustness via these requirements:
// * Object.MutTiedFields() gives us a tuple,
// * where the combined sizeofs all field types sums to sizeof(Object),
// * (thus we know we are exhaustively listing all fields)
// * where feeding each field back into ParamTraits succeeds,
// * and ParamTraits is only automated for BytesAlwaysValidT<T> types.
// (BytesAlwaysValidT rejects bool and enum types, and only accepts int/float
// types, or array or std::arrays of such types)
// (Yes, bit-field fields are rejected by MutTiedFields too)
template <class T>
struct QueueParamTraits_TiedFields {
template <typename ProducerView>
static bool Write(ProducerView& aProducerView, const T& aArg) {
const auto fields = TiedFields(aArg);
static_assert(AreAllBytesTiedFields<T>(),
"Are there missing fields or padding between fields?");
bool ok = true;
MapTuple(fields, [&](const auto& field) {
ok &= aProducerView.WriteParam(field);
return true;
});
return ok;
}
template <typename ConsumerView>
static bool Read(ConsumerView& aConsumerView, T* aArg) {
const auto fields = TiedFields(*aArg);
static_assert(AreAllBytesTiedFields<T>());
bool ok = true;
MapTuple(fields, [&](auto& field) {
ok &= aConsumerView.ReadParam(&field);
return true;
});
return ok;
}
};
// ---------------------------------------------------------------
// Adapted from IPC::EnumSerializer, this class safely handles enum values,
// validating that they are in range using the same EnumValidators as IPDL
// (namely ContiguousEnumValidator and ContiguousEnumValidatorInclusive).
template <typename E, typename EnumValidator>
struct EnumSerializer {
using ParamType = E;
using DataType = typename std::underlying_type<E>::type;
template <typename U>
static auto Write(ProducerView<U>& aProducerView, const ParamType& aValue) {
MOZ_RELEASE_ASSERT(
EnumValidator::IsLegalValue(static_cast<DataType>(aValue)));
return aProducerView.WriteParam(DataType(aValue));
}
template <typename U>
static bool Read(ConsumerView<U>& aConsumerView, ParamType* aResult) {
DataType value;
if (!aConsumerView.ReadParam(&value)) {
CrashReporter::RecordAnnotationCString(
CrashReporter::Annotation::IPCReadErrorReason, "Bad iter");
return false;
}
if (!EnumValidator::IsLegalValue(static_cast<DataType>(value))) {
CrashReporter::RecordAnnotationCString(
CrashReporter::Annotation::IPCReadErrorReason, "Illegal value");
return false;
}
*aResult = ParamType(value);
return true;
}
};
using IPC::ContiguousEnumValidator;
using IPC::ContiguousEnumValidatorInclusive;
template <typename E, E MinLegal, E HighBound>
struct ContiguousEnumSerializer
: EnumSerializer<E, ContiguousEnumValidator<E, MinLegal, HighBound>> {};
template <typename E, E MinLegal, E MaxLegal>
struct ContiguousEnumSerializerInclusive
: EnumSerializer<E,
ContiguousEnumValidatorInclusive<E, MinLegal, MaxLegal>> {
};
// ---------------------------------------------------------------
template <>
struct QueueParamTraits<webgl::TexUnpackBlobDesc> {
using ParamType = webgl::TexUnpackBlobDesc;
template <typename U>
static bool Write(ProducerView<U>& view, const ParamType& in) {
MOZ_RELEASE_ASSERT(!in.image);
MOZ_RELEASE_ASSERT(!in.sd);
const bool isDataSurf = bool(in.dataSurf);
if (!view.WriteParam(in.imageTarget) || !view.WriteParam(in.size) ||
!view.WriteParam(in.srcAlphaType) || !view.WriteParam(in.unpacking) ||
!view.WriteParam(in.cpuData) || !view.WriteParam(in.pboOffset) ||
!view.WriteParam(in.structuredSrcSize) ||
!view.WriteParam(in.applyUnpackTransforms) ||
!view.WriteParam(isDataSurf)) {
return false;
}
if (isDataSurf) {
const auto& surf = in.dataSurf;
gfx::DataSourceSurface::ScopedMap map(surf, gfx::DataSourceSurface::READ);
if (!map.IsMapped()) {
return false;
}
const auto& surfSize = surf->GetSize();
const auto stride = *MaybeAs<size_t>(map.GetStride());
if (!view.WriteParam(surfSize) || !view.WriteParam(surf->GetFormat()) ||
!view.WriteParam(stride)) {
return false;
}
const size_t dataSize = stride * surfSize.height;
const auto& begin = map.GetData();
const auto range = Range<const uint8_t>{begin, dataSize};
if (!view.WriteFromRange(range)) {
return false;
}
}
return true;
}
template <typename U>
static bool Read(ConsumerView<U>& view, ParamType* const out) {
bool isDataSurf;
if (!view.ReadParam(&out->imageTarget) || !view.ReadParam(&out->size) ||
!view.ReadParam(&out->srcAlphaType) ||
!view.ReadParam(&out->unpacking) || !view.ReadParam(&out->cpuData) ||
!view.ReadParam(&out->pboOffset) ||
!view.ReadParam(&out->structuredSrcSize) ||
!view.ReadParam(&out->applyUnpackTransforms) ||
!view.ReadParam(&isDataSurf)) {
return false;
}
if (isDataSurf) {
gfx::IntSize surfSize;
gfx::SurfaceFormat format;
size_t stride;
if (!view.ReadParam(&surfSize) || !view.ReadParam(&format) ||
!view.ReadParam(&stride)) {
return false;
}
const size_t dataSize = stride * surfSize.height;
const auto range = view.template ReadRange<uint8_t>(dataSize);
if (!range) return false;
// DataSourceSurface demands pointer-to-mutable.
const auto bytes = const_cast<uint8_t*>(range->begin().get());
out->dataSurf = gfx::Factory::CreateWrappingDataSourceSurface(
bytes, stride, surfSize, format);
MOZ_ASSERT(out->dataSurf);
}
return true;
}
};
// ---------------------------------------------------------------
template <>
struct QueueParamTraits<nsACString> {
using ParamType = nsACString;
template <typename U>
static bool Write(ProducerView<U>& aProducerView, const ParamType& aArg) {
if ((!aProducerView.WriteParam(aArg.IsVoid())) || aArg.IsVoid()) {
return false;
}
uint32_t len = aArg.Length();
if ((!aProducerView.WriteParam(len)) || (len == 0)) {
return false;
}
return aProducerView.Write(aArg.BeginReading(), len);
}
template <typename U>
static bool Read(ConsumerView<U>& aConsumerView, ParamType* aArg) {
bool isVoid = false;
if (!aConsumerView.ReadParam(&isVoid)) {
return false;
}
aArg->SetIsVoid(isVoid);
if (isVoid) {
return true;
}
uint32_t len = 0;
if (!aConsumerView.ReadParam(&len)) {
return false;
}
if (len == 0) {
*aArg = "";
return true;
}
char* buf = new char[len + 1];
if (!buf) {
return false;
}
if (!aConsumerView.Read(buf, len)) {
return false;
}
buf[len] = '\0';
aArg->Adopt(buf, len);
return true;
}
};
template <>
struct QueueParamTraits<nsAString> {
using ParamType = nsAString;
template <typename U>
static bool Write(ProducerView<U>& aProducerView, const ParamType& aArg) {
if ((!aProducerView.WriteParam(aArg.IsVoid())) || (aArg.IsVoid())) {
return false;
}
// DLP: No idea if this includes null terminator
uint32_t len = aArg.Length();
if ((!aProducerView.WriteParam(len)) || (len == 0)) {
return false;
}
constexpr const uint32_t sizeofchar = sizeof(typename ParamType::char_type);
return aProducerView.Write(aArg.BeginReading(), len * sizeofchar);
}
template <typename U>
static bool Read(ConsumerView<U>& aConsumerView, ParamType* aArg) {
bool isVoid = false;
if (!aConsumerView.ReadParam(&isVoid)) {
return false;
}
aArg->SetIsVoid(isVoid);
if (isVoid) {
return true;
}
// DLP: No idea if this includes null terminator
uint32_t len = 0;
if (!aConsumerView.ReadParam(&len)) {
return false;
}
if (len == 0) {
*aArg = nsString();
return true;
}
uint32_t sizeofchar = sizeof(typename ParamType::char_type);
typename ParamType::char_type* buf = nullptr;
buf = static_cast<typename ParamType::char_type*>(
malloc((len + 1) * sizeofchar));
if (!buf) {
return false;
}
if (!aConsumerView.Read(buf, len * sizeofchar)) {
return false;
}
buf[len] = L'\0';
aArg->Adopt(buf, len);
return true;
}
};
template <>
struct QueueParamTraits<nsCString> : public QueueParamTraits<nsACString> {
using ParamType = nsCString;
};
template <>
struct QueueParamTraits<nsString> : public QueueParamTraits<nsAString> {
using ParamType = nsString;
};
// ---------------------------------------------------------------
template <typename NSTArrayType,
bool = BytesAlwaysValidT<typename NSTArrayType::value_type>::value>
struct NSArrayQueueParamTraits;
// For ElementTypes that are !BytesAlwaysValidT
template <typename _ElementType>
struct NSArrayQueueParamTraits<nsTArray<_ElementType>, false> {
using ElementType = _ElementType;
using ParamType = nsTArray<ElementType>;
template <typename U>
static bool Write(ProducerView<U>& aProducerView, const ParamType& aArg) {
aProducerView.WriteParam(aArg.Length());
for (auto& elt : aArg) {
aProducerView.WriteParam(elt);
}
return true;
}
template <typename U>
static bool Read(ConsumerView<U>& aConsumerView, ParamType* aArg) {
size_t arrayLen;
if (!aConsumerView.ReadParam(&arrayLen)) {
return false;
}
if (!aArg->AppendElements(arrayLen, fallible)) {
return false;
}
for (auto i : IntegerRange(arrayLen)) {
ElementType& elt = aArg->ElementAt(i);
aConsumerView.ReadParam(elt);
}
return aConsumerView.Ok();
}
};
// For ElementTypes that are BytesAlwaysValidT
template <typename _ElementType>
struct NSArrayQueueParamTraits<nsTArray<_ElementType>, true> {
using ElementType = _ElementType;
using ParamType = nsTArray<ElementType>;
// TODO: Are there alignment issues?
template <typename U>
static bool Write(ProducerView<U>& aProducerView, const ParamType& aArg) {
size_t arrayLen = aArg.Length();
aProducerView.WriteParam(arrayLen);
return aProducerView.Write(&aArg[0], aArg.Length() * sizeof(ElementType));
}
template <typename U>
static bool Read(ConsumerView<U>& aConsumerView, ParamType* aArg) {
size_t arrayLen;
if (!aConsumerView.ReadParam(&arrayLen)) {
return false;
}
if (!aArg->AppendElements(arrayLen, fallible)) {
return false;
}
return aConsumerView.Read(aArg->Elements(), arrayLen * sizeof(ElementType));
}
};
template <typename ElementType>
struct QueueParamTraits<nsTArray<ElementType>>
: public NSArrayQueueParamTraits<nsTArray<ElementType>> {
using ParamType = nsTArray<ElementType>;
};
// ---------------------------------------------------------------
template <typename ArrayType,
bool = BytesAlwaysValidT<typename ArrayType::ElementType>::value>
struct ArrayQueueParamTraits;
// For ElementTypes that are !BytesAlwaysValidT
template <typename _ElementType, size_t Length>
struct ArrayQueueParamTraits<Array<_ElementType, Length>, false> {
using ElementType = _ElementType;
using ParamType = Array<ElementType, Length>;
template <typename U>
static auto Write(ProducerView<U>& aProducerView, const ParamType& aArg) {
for (const auto& elt : aArg) {
aProducerView.WriteParam(elt);
}
return aProducerView.Ok();
}
template <typename U>
static auto Read(ConsumerView<U>& aConsumerView, ParamType* aArg) {
for (auto& elt : *aArg) {
aConsumerView.ReadParam(elt);
}
return aConsumerView.Ok();
}
};
// For ElementTypes that are BytesAlwaysValidT
template <typename _ElementType, size_t Length>
struct ArrayQueueParamTraits<Array<_ElementType, Length>, true> {
using ElementType = _ElementType;
using ParamType = Array<ElementType, Length>;
template <typename U>
static auto Write(ProducerView<U>& aProducerView, const ParamType& aArg) {
return aProducerView.Write(aArg.begin(), sizeof(ElementType[Length]));
}
template <typename U>
static auto Read(ConsumerView<U>& aConsumerView, ParamType* aArg) {
return aConsumerView.Read(aArg->begin(), sizeof(ElementType[Length]));
}
};
template <typename ElementType, size_t Length>
struct QueueParamTraits<Array<ElementType, Length>>
: public ArrayQueueParamTraits<Array<ElementType, Length>> {
using ParamType = Array<ElementType, Length>;
};
// ---------------------------------------------------------------
template <typename ElementType>
struct QueueParamTraits<Maybe<ElementType>> {
using ParamType = Maybe<ElementType>;
template <typename U>
static bool Write(ProducerView<U>& aProducerView, const ParamType& aArg) {
aProducerView.WriteParam(static_cast<bool>(aArg));
if (aArg) {
aProducerView.WriteParam(aArg.ref());
}
return aProducerView.Ok();
}
template <typename U>
static bool Read(ConsumerView<U>& aConsumerView, ParamType* aArg) {
bool isSome;
if (!aConsumerView.ReadParam(&isSome)) {
return false;
}
if (!isSome) {
aArg->reset();
return true;
}
aArg->emplace();
return aConsumerView.ReadParam(aArg->ptr());
}
};
// ---------------------------------------------------------------
template <typename TypeA, typename TypeB>
struct QueueParamTraits<std::pair<TypeA, TypeB>> {
using ParamType = std::pair<TypeA, TypeB>;
template <typename U>
static bool Write(ProducerView<U>& aProducerView, const ParamType& aArg) {
aProducerView.WriteParam(aArg.first());
return aProducerView.WriteParam(aArg.second());
}
template <typename U>
static bool Read(ConsumerView<U>& aConsumerView, ParamType* aArg) {
aConsumerView.ReadParam(aArg->first());
return aConsumerView.ReadParam(aArg->second());
}
};
} // namespace mozilla::webgl
#endif // _QUEUEPARAMTRAITS_H_