blob: 2186f4dfdefd45b383d163f4ce94716a905e72bb [file] [log] [blame]
// Copyright 2021 The Pigweed 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
//
// https://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.
#include "pw_persistent_ram/persistent_buffer.h"
#include "pw_bytes/span.h"
#include "pw_checksum/crc16_ccitt.h"
#include "pw_status/status.h"
namespace pw::persistent_ram {
Status PersistentBufferWriter::DoWrite(ConstByteSpan data) {
if (ConservativeWriteLimit() == 0) {
return Status::OutOfRange();
}
if (ConservativeWriteLimit() < data.size_bytes()) {
return Status::ResourceExhausted();
}
if (data.empty()) {
return OkStatus();
}
std::memcpy(buffer_.data() + size_, data.data(), data.size_bytes());
// Only checksum newly written data.
checksum_ = checksum::Crc16Ccitt::Calculate(
ByteSpan(buffer_.data() + size_, data.size_bytes()), checksum_);
size_ = size_ + data.size_bytes(); // += on a volatile is deprecated in C++20
return OkStatus();
}
} // namespace pw::persistent_ram