hydra/src/hydra-queue-runner/nar-extractor.cc

83 lines
2.2 KiB
C++

#include "nar-extractor.hh"
#include "archive.hh"
#include <unordered_set>
using namespace nix;
struct Extractor : ParseSink
{
std::unordered_set<Path> filesToKeep {
"/nix-support/hydra-build-products",
"/nix-support/hydra-release-name",
"/nix-support/hydra-metrics",
};
NarMemberDatas & members;
NarMemberData * curMember = nullptr;
Path prefix;
Extractor(NarMemberDatas & members, const Path & prefix)
: members(members), prefix(prefix)
{ }
void createDirectory(const Path & path) override
{
members.insert_or_assign(prefix + path, NarMemberData { .type = FSAccessor::Type::tDirectory });
}
void createRegularFile(const Path & path) override
{
curMember = &members.insert_or_assign(prefix + path, NarMemberData {
.type = FSAccessor::Type::tRegular,
.fileSize = 0,
.contents = filesToKeep.count(path) ? std::optional("") : std::nullopt,
}).first->second;
}
std::optional<uint64_t> expectedSize;
std::unique_ptr<HashSink> hashSink;
void preallocateContents(uint64_t size) override
{
expectedSize = size;
hashSink = std::make_unique<HashSink>(htSHA256);
}
void receiveContents(std::string_view data) override
{
assert(expectedSize);
assert(curMember);
assert(hashSink);
*curMember->fileSize += data.size();
(*hashSink)(data);
if (curMember->contents) {
curMember->contents->append(data);
}
assert(curMember->fileSize <= expectedSize);
if (curMember->fileSize == expectedSize) {
auto [hash, len] = hashSink->finish();
assert(curMember->fileSize == len);
curMember->sha256 = hash;
hashSink.reset();
}
}
void createSymlink(const Path & path, const string & target) override
{
members.insert_or_assign(prefix + path, NarMemberData { .type = FSAccessor::Type::tSymlink });
}
};
void extractNarData(
Source & source,
const Path & prefix,
NarMemberDatas & members)
{
Extractor extractor(members, prefix);
parseDump(extractor, source);
// Note: this point may not be reached if we're in a coroutine.
}