72 lines
2.2 KiB
C++
72 lines
2.2 KiB
C++
// Copyright 2021 The Dawn Authors
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
#ifndef DAWNWIRE_BUFFERCONSUMER_IMPL_H_
|
|
#define DAWNWIRE_BUFFERCONSUMER_IMPL_H_
|
|
|
|
#include "dawn_wire/BufferConsumer.h"
|
|
|
|
#include <limits>
|
|
|
|
namespace dawn_wire {
|
|
|
|
template <typename BufferT>
|
|
template <typename T>
|
|
WireResult BufferConsumer<BufferT>::Peek(T** data) {
|
|
if (sizeof(T) > mSize) {
|
|
return WireResult::FatalError;
|
|
}
|
|
|
|
*data = reinterpret_cast<T*>(mBuffer);
|
|
return WireResult::Success;
|
|
}
|
|
|
|
template <typename BufferT>
|
|
template <typename T>
|
|
WireResult BufferConsumer<BufferT>::Next(T** data) {
|
|
if (sizeof(T) > mSize) {
|
|
return WireResult::FatalError;
|
|
}
|
|
|
|
*data = reinterpret_cast<T*>(mBuffer);
|
|
mBuffer += sizeof(T);
|
|
mSize -= sizeof(T);
|
|
return WireResult::Success;
|
|
}
|
|
|
|
template <typename BufferT>
|
|
template <typename T, typename N>
|
|
WireResult BufferConsumer<BufferT>::NextN(N count, T** data) {
|
|
static_assert(std::is_unsigned<N>::value, "|count| argument of NextN must be unsigned.");
|
|
|
|
constexpr size_t kMaxCountWithoutOverflows = std::numeric_limits<size_t>::max() / sizeof(T);
|
|
if (count > kMaxCountWithoutOverflows) {
|
|
return WireResult::FatalError;
|
|
}
|
|
|
|
// Cannot overflow because |count| is not greater than |kMaxCountWithoutOverflows|.
|
|
size_t totalSize = sizeof(T) * count;
|
|
if (totalSize > mSize) {
|
|
return WireResult::FatalError;
|
|
}
|
|
|
|
*data = reinterpret_cast<T*>(mBuffer);
|
|
mBuffer += totalSize;
|
|
mSize -= totalSize;
|
|
return WireResult::Success;
|
|
}
|
|
|
|
} // namespace dawn_wire
|
|
|
|
#endif // DAWNWIRE_BUFFERCONSUMER_IMPL_H_
|