components/entropy.c

   1 /* See LICENSE file for copyright and license details. */
   2 #if defined(__linux__)
   3         #include <inttypes.h>
   4         #include <stdio.h>
   5
   6         #include "../util.h"
   7
   8         const char *
   9         entropy(void)
  10         {
  11                 uint64_t num;
  12
  13                 if (pscanf("/proc/sys/kernel/random/entropy_avail",
  14                            "%" PRIu64, &num) != 1) {
  15                         return NULL;
  16                 }
  17
  18                 return bprintf("%" PRIu64, num);
  19         }
  20 #elif defined(__OpenBSD__)
  21         const char *
  22         entropy(void)
  23         {
  24                 /* Unicode Character 'INFINITY' (U+221E) */
  25                 return "\xe2\x88\x9e";
  26         }
  27 #endif