nix/libutil/gcrypt-hash.cc

   1 /* GNU Guix --- Functional package management for GNU
   2    Copyright (C) 2012, 2013  Ludovic Courtès <ludo@gnu.org>
   3
   4    This file is part of GNU Guix.
   5
   6    GNU Guix is free software; you can redistribute it and/or modify it
   7    under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or (at
   9    your option) any later version.
  10
  11    GNU Guix is distributed in the hope that it will be useful, but
  12    WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.  */
  18
  19 #include <config.h>
  20
  21 #include <gcrypt-hash.hh>
  22 #include <assert.h>
  23
  24 extern "C" {
  25
  26 void
  27 guix_hash_init (struct guix_hash_context *ctx, int algo)
  28 {
  29   gcry_error_t err;
  30
  31   err = gcry_md_open (&ctx->md_handle, algo, 0);
  32   assert (err == GPG_ERR_NO_ERROR);
  33 }
  34
  35 void
  36 guix_hash_update (struct guix_hash_context *ctx, const void *buffer, size_t len)
  37 {
  38   gcry_md_write (ctx->md_handle, buffer, len);
  39 }
  40
  41 void
  42 guix_hash_final (void *resbuf, struct guix_hash_context *ctx,
  43                  int algo)
  44 {
  45   memcpy (resbuf, gcry_md_read (ctx->md_handle, algo),
  46           gcry_md_get_algo_dlen (algo));
  47   gcry_md_close (ctx->md_handle);
  48   ctx->md_handle = NULL;
  49 }
  50
  51 }