#include "references.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, unsigned int 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 (unsigned int 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;

    string tail;

    RefScanSink() : hashSink(htSHA256) { }
    
    void operator () (const unsigned char * data, size_t 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);

    search(data, len, hashes, seen);

    unsigned int 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'). */
    foreach (PathSet::const_iterator, 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;
    foreach (StringSet::iterator, 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;
}


}
ute-urls’ RPC.</a><span class='msg-avail'>...<span class='msg-tooltip'>* nix/libstore/worker-protocol.hh (PROTOCOL_VERSION): Bump.
(WorkerOp): Add ‘wopSubstituteURLs’.
* nix/nix-daemon/nix-daemon.cc (performOp): Implement it.
* guix/store.scm (%protocol-version): Bump.
(operation-id): Add ‘substitute-urls’.
(substitute-urls): New procedure.
* tests/store.scm ("substitute-urls, default")
("substitute-urls, client-specified URLs")
("substitute-urls, disabled"): New tests.

Change-Id: I2c0119500c3a1eecfa5ebf32463ffb0f173161de
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2023-12-04 22:26:36 +0100'>2023-12-04</span></td><td><a href='/guix/commit/nix?id=d83d4488da5c3bb65867bffa2b8587a7c7b056cc'>daemon: Simplify “empty status” substitute error message.</a><span class='msg-avail'>...<span class='msg-tooltip'>* nix/libstore/build.cc (SubstitutionGoal::finished): Don’t show what
the empty status looks like.

Change-Id: Ie898432aeb047aff3d59024de6ed6d18f68903c4
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2023-09-24 02:00:00 +0200'>2023-09-24</span></td><td><a href='/guix/commit/nix?id=0500af5556307d0a4c14a23864e9e4bccd2643d7'>Revert "build: Add missing guix-gc.timer file to binary tarball."</a><span class='msg-avail'>...<span class='msg-tooltip'>This reverts commit 69f6edc1a8596d2cb4c67e0435d35633af6f3cbc.

The intention is good, but nodist_systemdservice_DATA are meant to be
disposable artefacts generated from corresponding ‘.in’ files.

etc/guix-gc.timer doesn't fit that description, breaking builds:

  $ make clean &amp;&amp; make
  …
  make[2]: *** No rule to make target 'etc/guix-gc.timer', needed by 'all-am'.  Stop.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2023-09-26 17:36:58 +0200'>2023-09-26</span></td><td><a href='/guix/commit/nix?id=95f21231352b66f92c466cb30f2258291e854f2f'>daemon: Add “git-download” built-in builder.</a><span class='msg-avail'>...<span class='msg-tooltip'>The new builder makes it possible to break cycles that occurs when the
fixed-output derivation for the source of a dependency of ‘git’ would
itself depend on ‘git’.

* guix/scripts/perform-download.scm (perform-git-download): New
procedure.
(perform-download): Move fixed-output derivation check to…
(guix-perform-download): … here.  Invoke ‘perform-download’ or
‘perform-git-download’ depending on what ‘derivation-builder’ returns.
* nix/libstore/builtins.cc (builtins): Add “git-download”.
* tests/derivations.scm ("built-in-builders"): Update.
("'git-download' built-in builder")
("'git-download' built-in builder, invalid hash")
("'git-download' built-in builder, invalid commit")
("'git-download' built-in builder, not found"): New tests.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2023-09-09 18:47:35 +0200'>2023-09-09</span></td><td><a href='/guix/commit/nix?id=cd469932758bf2bec1ff9c82aeb373e18730d0c4'>daemon: Fix build with GCC 13.</a><span class='msg-avail'>...<span class='msg-tooltip'>The sqlite.hh file uses fixed-width integer types from stdint.h. As
such, it needs to include &lt;cstdint&gt;. Without this include, the file
doesn't compile successfully with GCC13.

See: https://gcc.gnu.org/gcc-13/porting_to.html#header-dep-changes

* nix/libstore/sqlite.hh: include &lt;cstdint&gt;

Signed-off-by: Sören Tempel &lt;soeren@soeren-tempel.net&gt;
Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Sören Tempel</td></tr>
<tr><td><span title='2023-08-31 23:31:49 -0400'>2023-08-31</span></td><td><a href='/guix/commit/nix?id=69f6edc1a8596d2cb4c67e0435d35633af6f3cbc'>build: Add missing guix-gc.timer file to binary tarball.</a><span class='msg-avail'>...<span class='msg-tooltip'>Partially fixes &lt;https://issues.guix.gnu.org/65117&gt;.

* nix/local.mk (nodist_systemdservice_DATA): Add etc/guix-gc.timer.
</span></span></td><td>Maxim Cournoyer</td></tr>