t/helper/test-hash.c

   1 #include "test-tool.h"
   2 #include "cache.h"
   3
   4 int cmd_hash_impl(int ac, const char **av, int algo)
   5 {
   6         git_hash_ctx ctx;
   7         unsigned char hash[GIT_MAX_HEXSZ];
   8         unsigned bufsz = 8192;
   9         int binary = 0;
  10         char *buffer;
  11         const struct git_hash_algo *algop = &hash_algos[algo];
  12
  13         if (ac == 2) {
  14                 if (!strcmp(av[1], "-b"))
  15                         binary = 1;
  16                 else
  17                         bufsz = strtoul(av[1], NULL, 10) * 1024 * 1024;
  18         }
  19
  20         if (!bufsz)
  21                 bufsz = 8192;
  22
  23         while ((buffer = malloc(bufsz)) == NULL) {
  24                 fprintf(stderr, "bufsz %u is too big, halving...\n", bufsz);
  25                 bufsz /= 2;
  26                 if (bufsz < 1024)
  27                         die("OOPS");
  28         }
  29
  30         algop->init_fn(&ctx);
  31
  32         while (1) {
  33                 ssize_t sz, this_sz;
  34                 char *cp = buffer;
  35                 unsigned room = bufsz;
  36                 this_sz = 0;
  37                 while (room) {
  38                         sz = xread(0, cp, room);
  39                         if (sz == 0)
  40                                 break;
  41                         if (sz < 0)
  42                                 die_errno("test-hash");
  43                         this_sz += sz;
  44                         cp += sz;
  45                         room -= sz;
  46                 }
  47                 if (this_sz == 0)
  48                         break;
  49                 algop->update_fn(&ctx, buffer, this_sz);
  50         }
  51         algop->final_fn(hash, &ctx);
  52
  53         if (binary)
  54                 fwrite(hash, 1, algop->rawsz, stdout);
  55         else
  56                 puts(hash_to_hex_algop(hash, algop));
  57         return 0;
  58 }