release/src/router/dnscrypt/src/libnacl/cpucycles/osfreq.c

   1 static double osfreq(void)
   2 {
   3   FILE *f;
   4   double result;
   5   int s;
   6
   7   f = fopen("/sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq", "r");
   8   if (f) {
   9     s = fscanf(f,"%lf",&result);
  10     fclose(f);
  11     if (s > 0) return 1000.0 * result;
  12   }
  13
  14   f = fopen("/sys/devices/system/cpu/cpu0/clock_tick", "r");
  15   if (f) {
  16     s = fscanf(f,"%lf",&result);
  17     fclose(f);
  18     if (s > 0) return result;
  19   }
  20
  21   f = fopen("/proc/cpuinfo","r");
  22   if (f) {
  23     for (;;) {
  24       s = fscanf(f,"cpu MHz : %lf",&result);
  25       if (s > 0) break;
  26       if (s == 0) s = fscanf(f,"%*[^\n]\n");
  27       if (s < 0) { result = 0; break; }
  28     }
  29     fclose(f);
  30     if (result) return 1000000.0 * result;
  31   }
  32
  33   f = fopen("/proc/cpuinfo","r");
  34   if (f) {
  35     for (;;) {
  36       s = fscanf(f,"clock : %lf",&result);
  37       if (s > 0) break;
  38       if (s == 0) s = fscanf(f,"%*[^\n]\n");
  39       if (s < 0) { result = 0; break; }
  40     }
  41     fclose(f);
  42     if (result) return 1000000.0 * result;
  43   }
  44
  45   f = popen("/usr/sbin/lsattr -E -l proc0 -a frequency 2>/dev/null","r");
  46   if (f) {
  47     s = fscanf(f,"frequency %lf",&result);
  48     pclose(f);
  49     if (s > 0) return result;
  50   }
  51
  52   f = popen("/usr/sbin/psrinfo -v 2>/dev/null","r");
  53   if (f) {
  54     for (;;) {
  55       s = fscanf(f," The %*s processor operates at %lf MHz",&result);
  56       if (s > 0) break;
  57       if (s == 0) s = fscanf(f,"%*[^\n]\n");
  58       if (s < 0) { result = 0; break; }
  59     }
  60     pclose(f);
  61     if (result) return 1000000.0 * result;
  62   }
  63
  64   return 0;
  65 }