lix/src/nix-hash/nix-hash.cc
Eelco Dolstra d58a11e019 * Shorten SHA-256 hashes used in store path name generation to 160
bits, then encode them in a radix-32 representation (using digits
  and letters except e, o, u, and t).  This produces store paths like
  /nix/store/4i0zb0z7f88mwghjirkz702a71dcfivn-aterm-2.3.1.  The nice
  thing about this is that the hash part of the file name is still 32
  characters, as before with MD5.

  (Of course, shortening SHA-256 to 160 bits makes it no better than
  SHA-160 in theory, but hopefully it's a bit more resistant to
  attacks; it's certainly a lot slower.)
2005-01-14 16:04:03 +00:00

40 lines
895 B
C++

#include <iostream>
#include "hash.hh"
#include "shared.hh"
#include "help.txt.hh"
void printHelp()
{
cout << string((char *) helpText, sizeof helpText);
}
void run(Strings args)
{
HashType ht = htMD5;
bool flat = false;
for (Strings::iterator i = args.begin();
i != args.end(); i++)
{
if (*i == "--flat") flat = true;
else if (*i == "--type") {
++i;
if (i == args.end()) throw UsageError("`--type' requires an argument");
if (*i == "md5") ht = htMD5;
else if (*i == "sha1") ht = htSHA1;
else if (*i == "sha256") ht = htSHA256;
else throw UsageError(format("unknown hash type `%1%'") % *i);
}
else
cout << format("%1%\n") % printHash(
(flat ? hashFile(*i, ht) : hashPath(*i, ht)));
}
}
string programId = "nix-hash";