Use the clock_gettime() instead of obsolescent gettimeofday()

Patch by: michaelortmann

configure.ac

@@ -112,7 +112,7 @@ AX_TYPE_SOCKLEN_T
 AX_CREATE_STDINT_H([eggint.h])
 
 # Checks for functions and their arguments.
-AC_CHECK_FUNCS([dprintf explicit_bzero memset_explicit explicit_memset getrandom inet_aton memset_s snprintf strlcpy vsnprintf])
+AC_CHECK_FUNCS([clock_gettime dprintf explicit_bzero memset_explicit explicit_memset getrandom inet_aton memset_s snprintf strlcpy vsnprintf])
 AC_FUNC_SELECT_ARGTYPES
 EGG_FUNC_B64_NTOP
 AC_FUNC_MMAP

src/main.c

@@ -919,17 +919,23 @@ static void mainloop(int toplevel)
 static void init_random(void) {
   unsigned int seed;
 #ifdef HAVE_GETRANDOM
-  if (getrandom(&seed, sizeof(seed), 0) != sizeof(seed)) {
+  if (getrandom(&seed, sizeof seed, 0) != (sizeof seed)) {
     if (errno != ENOSYS) {
       fatal("ERROR: getrandom()\n", 0);
     } else {
       /* getrandom() is available in header but syscall is not!
        * This can happen with glibc>=2.25 and linux<3.17
        */
 #endif
+#ifdef HAVE_CLOCK_GETTIME
+      struct timespec tp;
+      clock_gettime(CLOCK_REALTIME, &tp);
+      seed = ((uint64_t) tp.tv_sec * tp.tv_nsec) ^ getpid();
+#else
       struct timeval tp;
       gettimeofday(&tp, NULL);
-      seed = (((int64_t) tp.tv_sec * tp.tv_usec)) ^ getpid();
+      seed = ((uint64_t) tp.tv_sec * tp.tv_usec) ^ getpid();
+#endif
 #ifdef HAVE_GETRANDOM
     }
   }