about summary refs log tree commit diff
path: root/third_party/nix/src/libstore/references.cc
diff options
context:
space:
mode:
authorVincent Ambo <mail@tazj.in>2022-05-18T15·39+0200
committerclbot <clbot@tvl.fyi>2022-05-19T14·08+0000
commitd127f9bd0e7b9b2e0df2de8a2227f77c0907468d (patch)
tree68455040d88b8e0c2817601db88ede450873ff8e /third_party/nix/src/libstore/references.cc
parentc85291c602ac666421627d6934ebc6d5be1b93e1 (diff)
chore(3p/nix): unvendor tvix 0.1 r/4098
Nothing is using this now, and we'll likely never pick this up again,
but we learned a lot in the process.

Every now and then this breaks in some bizarre way on channel bumps
and it's just a waste of time to maintain that.

Change-Id: Idcf2f5acd4ca7070ce18d7149cbfc0d967dc0a44
Reviewed-on: https://cl.tvl.fyi/c/depot/+/5632
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Reviewed-by: lukegb <lukegb@tvl.fyi>
Autosubmit: tazjin <tazjin@tvl.su>
Diffstat (limited to 'third_party/nix/src/libstore/references.cc')
-rw-r--r--third_party/nix/src/libstore/references.cc126
1 files changed, 0 insertions, 126 deletions
diff --git a/third_party/nix/src/libstore/references.cc b/third_party/nix/src/libstore/references.cc
deleted file mode 100644
index f120439c1060..000000000000
--- a/third_party/nix/src/libstore/references.cc
+++ /dev/null
@@ -1,126 +0,0 @@
-#include "libstore/references.hh"
-
-#include <cstdlib>
-#include <map>
-
-#include <glog/logging.h>
-
-#include "libutil/archive.hh"
-#include "libutil/hash.hh"
-#include "libutil/util.hh"
-
-namespace nix {
-
-constexpr unsigned int kRefLength = 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 (bool& i : isBase32) {
-      i = false;
-    }
-    for (char base32Char : base32Chars) {
-      isBase32[static_cast<unsigned char>(base32Char)] = true;
-    }
-    initialised = true;
-  }
-
-  for (size_t i = 0; i + kRefLength <= len;) {
-    int j = 0;
-    bool match = true;
-    for (j = kRefLength - 1; j >= 0; --j) {
-      if (!isBase32[s[i + j]]) {
-        i += j + 1;
-        match = false;
-        break;
-      }
-    }
-    if (!match) {
-      continue;
-    }
-    std::string ref(reinterpret_cast<const char*>(s) + i, kRefLength);
-    if (hashes.find(ref) != hashes.end()) {
-      DLOG(INFO) << "found reference to '" << ref << "' at offset " << i;
-      seen.insert(ref);
-      hashes.erase(ref);
-    }
-    ++i;
-  }
-}
-
-struct RefScanSink : Sink {
-  HashSink hashSink;
-  StringSet hashes;
-  StringSet seen;
-
-  std::string tail;
-
-  RefScanSink() : hashSink(htSHA256) {}
-
-  void operator()(const unsigned char* data, size_t len) override;
-};
-
-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. */
-  std::string s = tail + std::string(reinterpret_cast<const char*>(data),
-                                     len > kRefLength ? kRefLength : len);
-  search(reinterpret_cast<const unsigned char*>(s.data()), s.size(), hashes,
-         seen);
-
-  search(data, len, hashes, seen);
-
-  size_t tailLen = len <= kRefLength ? len : kRefLength;
-  tail =
-      std::string(tail, tail.size() < kRefLength - tailLen
-                            ? 0
-                            : tail.size() - (kRefLength - tailLen)) +
-      std::string(reinterpret_cast<const char*>(data) + len - tailLen, tailLen);
-}
-
-PathSet scanForReferences(const std::string& path, const PathSet& refs,
-                          HashResult& hash) {
-  RefScanSink sink;
-  std::map<std::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) {
-    std::string baseName = baseNameOf(i);
-    std::string::size_type pos = baseName.find('-');
-    if (pos == std::string::npos) {
-      throw Error(format("bad reference '%1%'") % i);
-    }
-    std::string s = std::string(baseName, 0, pos);
-    assert(s.size() == kRefLength);
-    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<std::string, Path>::iterator j;
-    if ((j = backMap.find(i)) == backMap.end()) {
-      abort();
-    }
-    found.insert(j->second);
-  }
-
-  hash = sink.hashSink.finish();
-
-  return found;
-}
-
-}  // namespace nix