components/swap.c

   1 /* See LICENSE file for copyright and license details. */
   2 #if defined(__linux__)
   3         #include <errno.h>
   4         #include <stdio.h>
   5         #include <string.h>
   6
   7         #include "../util.h"
   8
   9         static size_t
  10         pread(const char *path, char *buf, size_t bufsiz)
  11         {
  12                 FILE *fp;
  13                 size_t bytes_read;
  14
  15                 if (!(fp = fopen(path, "r"))) {
  16                         fprintf(stderr, "fopen '%s': %s\n", path,
  17                                 strerror(errno));
  18                         return 0;
  19                 }
  20                 if ((bytes_read = fread(buf, sizeof(char), bufsiz, fp)) == 0) {
  21                         fprintf(stderr, "fread '%s': %s\n", path,
  22                                 strerror(errno));
  23                         fclose(fp);
  24                         return 0;
  25                 }
  26                 fclose(fp);
  27
  28                 buf[bytes_read] = '\0';
  29
  30                 return bytes_read;
  31         }
  32
  33         const char *
  34         swap_free(void)
  35         {
  36                 long total, free;
  37                 char *match;
  38
  39                 if (!pread("/proc/meminfo", buf, sizeof(buf) - 1)) {
  40                         return NULL;
  41                 }
  42
  43                 if ((match = strstr(buf, "SwapTotal")) == NULL)
  44                         return NULL;
  45                 sscanf(match, "SwapTotal: %ld kB\n", &total);
  46
  47                 if ((match = strstr(buf, "SwapFree")) == NULL)
  48                         return NULL;
  49                 sscanf(match, "SwapFree: %ld kB\n", &free);
  50
  51                 return bprintf("%f", (float)free / 1024 / 1024);
  52         }
  53
  54         const char *
  55         swap_perc(void)
  56         {
  57                 long total, free, cached;
  58                 char *match;
  59
  60                 if (!pread("/proc/meminfo", buf, sizeof(buf) - 1)) {
  61                         return NULL;
  62                 }
  63
  64                 if ((match = strstr(buf, "SwapTotal")) == NULL)
  65                         return NULL;
  66                 sscanf(match, "SwapTotal: %ld kB\n", &total);
  67
  68                 if ((match = strstr(buf, "SwapCached")) == NULL)
  69                         return NULL;
  70                 sscanf(match, "SwapCached: %ld kB\n", &cached);
  71
  72                 if ((match = strstr(buf, "SwapFree")) == NULL)
  73                         return NULL;
  74                 sscanf(match, "SwapFree: %ld kB\n", &free);
  75
  76                 return bprintf("%d", 100 * (total - free - cached) / total);
  77         }
  78
  79         const char *
  80         swap_total(void)
  81         {
  82                 long total;
  83                 char *match;
  84
  85                 if (!pread("/proc/meminfo", buf, sizeof(buf) - 1)) {
  86                         return NULL;
  87                 }
  88
  89                 if ((match = strstr(buf, "SwapTotal")) == NULL)
  90                         return NULL;
  91                 sscanf(match, "SwapTotal: %ld kB\n", &total);
  92
  93                 return bprintf("%f", (float)total / 1024 / 1024);
  94         }
  95
  96         const char *
  97         swap_used(void)
  98         {
  99                 long total, free, cached;
 100                 char *match;
 101
 102                 if (!pread("/proc/meminfo", buf, sizeof(buf) - 1)) {
 103                         return NULL;
 104                 }
 105
 106                 if ((match = strstr(buf, "SwapTotal")) == NULL)
 107                         return NULL;
 108                 sscanf(match, "SwapTotal: %ld kB\n", &total);
 109
 110                 if ((match = strstr(buf, "SwapCached")) == NULL)
 111                         return NULL;
 112                 sscanf(match, "SwapCached: %ld kB\n", &cached);
 113
 114                 if ((match = strstr(buf, "SwapFree")) == NULL)
 115                         return NULL;
 116                 sscanf(match, "SwapFree: %ld kB\n", &free);
 117
 118                 return bprintf("%f", (float)(total - free - cached) / 1024 / 1024);
 119         }
 120 #elif defined(__OpenBSD__)
 121         /* unimplemented */
 122 #endif