lix/src/libstore/export-import.cc

103 lines
3 KiB
C++

#include "serialise.hh"
#include "store-api.hh"
#include "archive.hh"
#include "common-protocol.hh"
#include "common-protocol-impl.hh"
#include <algorithm>
namespace nix {
void Store::exportPaths(const StorePathSet & paths, Sink & sink)
{
auto sorted = topoSortPaths(paths);
std::reverse(sorted.begin(), sorted.end());
std::string doneLabel("paths exported");
//logger->incExpected(doneLabel, sorted.size());
for (auto & path : sorted) {
//Activity act(*logger, lvlInfo, "exporting path '%s'", path);
sink << 1;
exportPath(path, sink);
//logger->incProgress(doneLabel);
}
sink << 0;
}
void Store::exportPath(const StorePath & path, Sink & sink)
{
auto info = queryPathInfo(path);
HashSink hashSink(HashType::SHA256);
TeeSink teeSink(sink, hashSink);
teeSink << narFromPath(path);
/* Refuse to export paths that have changed. This prevents
filesystem corruption from spreading to other machines.
Don't complain if the stored hash is zero (unknown). */
Hash hash = hashSink.currentHash().first;
if (hash != info->narHash && info->narHash != Hash(info->narHash.type))
throw Error("hash of path '%s' has changed from '%s' to '%s'!",
printStorePath(path), info->narHash.to_string(Base::Base32, true), hash.to_string(Base::Base32, true));
teeSink
<< exportMagic
<< printStorePath(path);
teeSink << CommonProto::write(*this,
CommonProto::WriteConn {},
info->references);
teeSink
<< (info->deriver ? printStorePath(*info->deriver) : "")
<< 0;
}
StorePaths Store::importPaths(Source & source, CheckSigsFlag checkSigs)
{
StorePaths res;
while (true) {
auto n = readNum<uint64_t>(source);
if (n == 0) break;
if (n != 1) throw Error("input doesn't look like something created by 'nix-store --export'");
/* Extract the NAR from the source. */
StringSink saved;
saved << copyNAR(source);
uint32_t magic = readInt(source);
if (magic != exportMagic)
throw Error("Nix archive cannot be imported; wrong format");
auto path = parseStorePath(readString(source));
//Activity act(*logger, lvlInfo, "importing path '%s'", info.path);
auto references = CommonProto::Serialise<StorePathSet>::read(*this,
CommonProto::ReadConn { .from = source });
auto deriver = readString(source);
auto narHash = hashString(HashType::SHA256, saved.s);
ValidPathInfo info { path, narHash };
if (deriver != "")
info.deriver = parseStorePath(deriver);
info.references = references;
info.narSize = saved.s.size();
// Ignore optional legacy signature.
if (readInt(source) == 1)
readString(source);
// Can't use underlying source, which would have been exhausted
auto source = StringSource(saved.s);
addToStore(info, source, NoRepair, checkSigs);
res.push_back(info.path);
}
return res;
}
}