RecordInfo validateRecord(ByteRange range, uint32_t fileId) {
if (range.size() <= headerSize()) { // records may not be empty
return {0, {}};
}
const Header* header = reinterpret_cast<const Header*>(range.begin());
range.advance(sizeof(Header));
if (header->magic != Header::kMagic ||
header->version != 0 ||
header->hashFunction != 0 ||
header->flags != 0 ||
(fileId != 0 && header->fileId != fileId) ||
header->dataLength > range.size()) {
return {0, {}};
}
if (headerHash(*header) != header->headerHash) {
return {0, {}};
}
range.reset(range.begin(), header->dataLength);
if (dataHash(range) != header->dataHash) {
return {0, {}};
}
return {header->fileId, range};
}
