source: vendor/glibc/2.3.x/crypt/md5test.c

#include <string.h>
#include "md5.h"

static const struct
{
  const char *input;
  const char result[16];
} tests[] =
  {
    { "",
      "\xd4\x1d\x8c\xd9\x8f\x00\xb2\x04\xe9\x80\x09\x98\xec\xf8\x42\x7e" },
    { "a",
      "\x0c\xc1\x75\xb9\xc0\xf1\xb6\xa8\x31\xc3\x99\xe2\x69\x77\x26\x61" },
    { "abc",
      "\x90\x01\x50\x98\x3c\xd2\x4f\xb0\xd6\x96\x3f\x7d\x28\xe1\x7f\x72" },
    { "message digest",
      "\xf9\x6b\x69\x7d\x7c\xb7\x93\x8d\x52\x5a\x2f\x31\xaa\xf1\x61\xd0" },
    { "abcdefghijklmnopqrstuvwxyz",
      "\xc3\xfc\xd3\xd7\x61\x92\xe4\x00\x7d\xfb\x49\x6c\xca\x67\xe1\x3b" },
    { "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789",
      "\xd1\x74\xab\x98\xd2\x77\xd9\xf5\xa5\x61\x1c\x2c\x9f\x41\x9d\x9f" },
    { "123456789012345678901234567890123456789012345678901234567890"
      "12345678901234567890",
      "\x57\xed\xf4\xa2\x2b\xe3\xc9\x55\xac\x49\xda\x2e\x21\x07\xb6\x7a" }
  };


int
main (int argc, char *argv[])
{
  struct md5_ctx ctx;
  char sum[16];
  int result = 0;
  int cnt;

  for (cnt = 0; cnt < (int) (sizeof (tests) / sizeof (tests[0])); ++cnt)
    {
      int i;

      __md5_init_ctx (&ctx);
      __md5_process_bytes (tests[cnt].input, strlen (tests[cnt].input), &ctx);
      __md5_finish_ctx (&ctx, sum);
      result |= memcmp (tests[cnt].result, sum, 16);

      __md5_init_ctx (&ctx);
      for (i = 0; tests[cnt].input[i] != '\0'; ++i)
        __md5_process_bytes (&tests[cnt].input[i], 1, &ctx);
      __md5_finish_ctx (&ctx, sum);
      result |= memcmp (tests[cnt].result, sum, 16);
    }

  return result;
}