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#include "store-api.hh"
#include "archive.hh"
#include "worker-protocol.hh"
#include <algorithm>
namespace nix {
struct HashAndWriteSink : Sink
{
Sink & writeSink;
HashSink hashSink;
HashAndWriteSink(Sink & writeSink) : writeSink(writeSink), hashSink(htSHA256)
{
}
virtual void operator () (const unsigned char * data, size_t len)
{
writeSink(data, len);
hashSink(data, len);
}
Hash currentHash()
{
return hashSink.currentHash().first;
}
};
void Store::exportPaths(const Paths & paths, Sink & sink)
{
Paths sorted = topoSortPaths(PathSet(paths.begin(), paths.end()));
std::reverse(sorted.begin(), sorted.end());
std::string doneLabel("paths exported");
logger->incExpected(doneLabel, sorted.size());
for (auto & path : sorted) {
Activity act(*logger, lvlInfo, format("exporting path ‘%s’") % path);
sink << 1;
exportPath(path, sink);
logger->incProgress(doneLabel);
}
sink << 0;
}
void Store::exportPath(const Path & path, Sink & sink)
{
auto info = queryPathInfo(path);
HashAndWriteSink hashAndWriteSink(sink);
narFromPath(path, hashAndWriteSink);
/* 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 = hashAndWriteSink.currentHash();
if (hash != info->narHash && info->narHash != Hash(info->narHash.type))
throw Error(format("hash of path ‘%1%’ has changed from ‘%2%’ to ‘%3%’!") % path
% printHash(info->narHash) % printHash(hash));
hashAndWriteSink << exportMagic << path << info->references << info->deriver << 0;
}
struct TeeSource : Source
{
Source & readSource;
ref<std::string> data;
TeeSource(Source & readSource)
: readSource(readSource)
, data(make_ref<std::string>())
{
}
size_t read(unsigned char * data, size_t len)
{
size_t n = readSource.read(data, len);
this->data->append((char *) data, n);
return n;
}
};
struct NopSink : ParseSink
{
};
Paths Store::importPaths(Source & source, std::shared_ptr<FSAccessor> accessor, bool dontCheckSigs)
{
Paths res;
while (true) {
unsigned long long n = readLongLong(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. */
TeeSource tee(source);
NopSink sink;
parseDump(sink, tee);
uint32_t magic = readInt(source);
if (magic != exportMagic)
throw Error("Nix archive cannot be imported; wrong format");
ValidPathInfo info;
info.path = readStorePath(*this, source);
Activity act(*logger, lvlInfo, format("importing path ‘%s’") % info.path);
info.references = readStorePaths<PathSet>(*this, source);
info.deriver = readString(source);
if (info.deriver != "") assertStorePath(info.deriver);
info.narHash = hashString(htSHA256, *tee.data);
info.narSize = tee.data->size();
// Ignore optional legacy signature.
if (readInt(source) == 1)
readString(source);
addToStore(info, tee.data, false, dontCheckSigs, accessor);
res.push_back(info.path);
}
return res;
}
}
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