diff options
Diffstat (limited to 'third_party/nix/src/libstore/references.cc')
| -rw-r--r-- | third_party/nix/src/libstore/references.cc | 186 |
1 files changed, 87 insertions, 99 deletions
diff --git a/third_party/nix/src/libstore/references.cc b/third_party/nix/src/libstore/references.cc index 5b7eb1f846..df3ee73fde 100644 --- a/third_party/nix/src/libstore/references.cc +++ b/third_party/nix/src/libstore/references.cc @@ -1,122 +1,110 @@ #include "references.hh" +#include <cstdlib> +#include <map> +#include "archive.hh" #include "hash.hh" #include "util.hh" -#include "archive.hh" - -#include <map> -#include <cstdlib> - namespace nix { - static unsigned int refLength = 32; /* characters */ - -static void search(const unsigned char * s, size_t len, - StringSet & hashes, StringSet & seen) -{ - static bool initialised = false; - static bool isBase32[256]; - if (!initialised) { - for (unsigned int i = 0; i < 256; ++i) isBase32[i] = false; - for (unsigned int i = 0; i < base32Chars.size(); ++i) - isBase32[(unsigned char) base32Chars[i]] = true; - initialised = true; - } - - for (size_t i = 0; i + refLength <= len; ) { - int j; - bool match = true; - for (j = refLength - 1; j >= 0; --j) - if (!isBase32[(unsigned char) s[i + j]]) { - i += j + 1; - match = false; - break; - } - if (!match) continue; - string ref((const char *) s + i, refLength); - if (hashes.find(ref) != hashes.end()) { - debug(format("found reference to '%1%' at offset '%2%'") - % ref % i); - seen.insert(ref); - hashes.erase(ref); - } - ++i; +static void search(const unsigned char* s, size_t len, StringSet& hashes, + StringSet& seen) { + static bool initialised = false; + static bool isBase32[256]; + if (!initialised) { + for (unsigned int i = 0; i < 256; ++i) isBase32[i] = false; + for (unsigned int i = 0; i < base32Chars.size(); ++i) + isBase32[(unsigned char)base32Chars[i]] = true; + initialised = true; + } + + for (size_t i = 0; i + refLength <= len;) { + int j; + bool match = true; + for (j = refLength - 1; j >= 0; --j) + if (!isBase32[(unsigned char)s[i + j]]) { + i += j + 1; + match = false; + break; + } + if (!match) continue; + string ref((const char*)s + i, refLength); + if (hashes.find(ref) != hashes.end()) { + debug(format("found reference to '%1%' at offset '%2%'") % ref % i); + seen.insert(ref); + hashes.erase(ref); } + ++i; + } } +struct RefScanSink : Sink { + HashSink hashSink; + StringSet hashes; + StringSet seen; -struct RefScanSink : Sink -{ - HashSink hashSink; - StringSet hashes; - StringSet seen; + string tail; - string tail; + RefScanSink() : hashSink(htSHA256) {} - RefScanSink() : hashSink(htSHA256) { } - - void operator () (const unsigned char * data, size_t len); + void operator()(const unsigned char* data, size_t len); }; +void RefScanSink::operator()(const unsigned char* data, size_t len) { + hashSink(data, len); -void RefScanSink::operator () (const unsigned char * data, size_t len) -{ - hashSink(data, len); - - /* It's possible that a reference spans the previous and current - fragment, so search in the concatenation of the tail of the - previous fragment and the start of the current fragment. */ - string s = tail + string((const char *) data, len > refLength ? refLength : len); - search((const unsigned char *) s.data(), s.size(), hashes, seen); + /* It's possible that a reference spans the previous and current + fragment, so search in the concatenation of the tail of the + previous fragment and the start of the current fragment. */ + string s = + tail + string((const char*)data, len > refLength ? refLength : len); + search((const unsigned char*)s.data(), s.size(), hashes, seen); - search(data, len, hashes, seen); + search(data, len, hashes, seen); - size_t tailLen = len <= refLength ? len : refLength; - tail = - string(tail, tail.size() < refLength - tailLen ? 0 : tail.size() - (refLength - tailLen)) + - string((const char *) data + len - tailLen, tailLen); + size_t tailLen = len <= refLength ? len : refLength; + tail = string(tail, tail.size() < refLength - tailLen + ? 0 + : tail.size() - (refLength - tailLen)) + + string((const char*)data + len - tailLen, tailLen); } - -PathSet scanForReferences(const string & path, - const PathSet & refs, HashResult & hash) -{ - RefScanSink sink; - std::map<string, Path> backMap; - - /* For efficiency (and a higher hit rate), just search for the - hash part of the file name. (This assumes that all references - have the form `HASH-bla'). */ - for (auto & i : refs) { - string baseName = baseNameOf(i); - string::size_type pos = baseName.find('-'); - if (pos == string::npos) - throw Error(format("bad reference '%1%'") % i); - string s = string(baseName, 0, pos); - assert(s.size() == refLength); - assert(backMap.find(s) == backMap.end()); - // parseHash(htSHA256, s); - sink.hashes.insert(s); - backMap[s] = i; - } - - /* Look for the hashes in the NAR dump of the path. */ - dumpPath(path, sink); - - /* Map the hashes found back to their store paths. */ - PathSet found; - for (auto & i : sink.seen) { - std::map<string, Path>::iterator j; - if ((j = backMap.find(i)) == backMap.end()) abort(); - found.insert(j->second); - } - - hash = sink.hashSink.finish(); - - return found; +PathSet scanForReferences(const string& path, const PathSet& refs, + HashResult& hash) { + RefScanSink sink; + std::map<string, Path> backMap; + + /* For efficiency (and a higher hit rate), just search for the + hash part of the file name. (This assumes that all references + have the form `HASH-bla'). */ + for (auto& i : refs) { + string baseName = baseNameOf(i); + string::size_type pos = baseName.find('-'); + if (pos == string::npos) throw Error(format("bad reference '%1%'") % i); + string s = string(baseName, 0, pos); + assert(s.size() == refLength); + assert(backMap.find(s) == backMap.end()); + // parseHash(htSHA256, s); + sink.hashes.insert(s); + backMap[s] = i; + } + + /* Look for the hashes in the NAR dump of the path. */ + dumpPath(path, sink); + + /* Map the hashes found back to their store paths. */ + PathSet found; + for (auto& i : sink.seen) { + std::map<string, Path>::iterator j; + if ((j = backMap.find(i)) == backMap.end()) abort(); + found.insert(j->second); + } + + hash = sink.hashSink.finish(); + + return found; } - -} +} // namespace nix |