components/swap.c

   1 /* See LICENSE file for copyright and license details. */
   2 #include <errno.h>
   3 #include <stdio.h>
   4 #include <string.h>
   5
   6 #include "../util.h"
   7
   8 #if defined(__linux__)
   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                         warn("fopen '%s':", path);
  17                         return 0;
  18                 }
  19                 if (!(bytes_read = fread(buf, sizeof(char), bufsiz, fp))) {
  20                         warn("fread '%s':", path);
  21                         fclose(fp);
  22                         return 0;
  23                 }
  24                 fclose(fp);
  25
  26                 buf[bytes_read] = '\0';
  27
  28                 return bytes_read;
  29         }
  30
  31         const char *
  32         swap_free(void)
  33         {
  34                 long total, free;
  35                 char *match;
  36
  37                 if (!pread("/proc/meminfo", buf, sizeof(buf) - 1)) {
  38                         return NULL;
  39                 }
  40
  41                 if (!(match = strstr(buf, "SwapTotal"))) {
  42                         return NULL;
  43                 }
  44                 sscanf(match, "SwapTotal: %ld kB\n", &total);
  45
  46                 if (!(match = strstr(buf, "SwapFree"))) {
  47                         return NULL;
  48                 }
  49                 sscanf(match, "SwapFree: %ld kB\n", &free);
  50
  51                 return fmt_human_2(free * 1024, "B");
  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"))) {
  65                         return NULL;
  66                 }
  67                 sscanf(match, "SwapTotal: %ld kB\n", &total);
  68
  69                 if (!(match = strstr(buf, "SwapCached"))) {
  70                         return NULL;
  71                 }
  72                 sscanf(match, "SwapCached: %ld kB\n", &cached);
  73
  74                 if (!(match = strstr(buf, "SwapFree"))) {
  75                         return NULL;
  76                 }
  77                 sscanf(match, "SwapFree: %ld kB\n", &free);
  78
  79                 if (total == 0) {
  80                         return NULL;
  81                 }
  82
  83                 return bprintf("%d%%", 100 * (total - free - cached) / total);
  84         }
  85
  86         const char *
  87         swap_total(void)
  88         {
  89                 long total;
  90                 char *match;
  91
  92                 if (!pread("/proc/meminfo", buf, sizeof(buf) - 1)) {
  93                         return NULL;
  94                 }
  95
  96                 if (!(match = strstr(buf, "SwapTotal"))) {
  97                         return NULL;
  98                 }
  99                 sscanf(match, "SwapTotal: %ld kB\n", &total);
 100
 101                 return fmt_human_2(total * 1024, "B");
 102         }
 103
 104         const char *
 105         swap_used(void)
 106         {
 107                 long total, free, cached;
 108                 char *match;
 109
 110                 if (!pread("/proc/meminfo", buf, sizeof(buf) - 1)) {
 111                         return NULL;
 112                 }
 113
 114                 if (!(match = strstr(buf, "SwapTotal"))) {
 115                         return NULL;
 116                 }
 117                 sscanf(match, "SwapTotal: %ld kB\n", &total);
 118
 119                 if (!(match = strstr(buf, "SwapCached"))) {
 120                         return NULL;
 121                 }
 122                 sscanf(match, "SwapCached: %ld kB\n", &cached);
 123
 124                 if (!(match = strstr(buf, "SwapFree"))) {
 125                         return NULL;
 126                 }
 127                 sscanf(match, "SwapFree: %ld kB\n", &free);
 128
 129                 return fmt_human_2((total - free - cached) * 1024, "B");
 130         }
 131 #elif defined(__OpenBSD__)
 132         #include <stdlib.h>
 133         #include <sys/param.h> /* dbtob */
 134         #include <sys/swap.h>
 135         #include <sys/types.h>
 136         #include <unistd.h>
 137
 138         static void
 139         getstats(int *total, int *used)
 140         {
 141                 struct swapent *sep, *fsep;
 142                 int rnswap, nswap, i;
 143
 144                 nswap = swapctl(SWAP_NSWAP, 0, 0);
 145                 if (nswap < 1) {
 146                         warn("swaptctl 'SWAP_NSWAP':");
 147                 }
 148
 149                 fsep = sep = calloc(nswap, sizeof(*sep));
 150                 if (!sep) {
 151                         warn("calloc 'nswap':");
 152                 }
 153
 154                 rnswap = swapctl(SWAP_STATS, (void *)sep, nswap);
 155                 if (rnswap < 0) {
 156                         warn("swapctl 'SWAP_STATA':");
 157                 }
 158
 159                 if (nswap != rnswap) {
 160                         warn("getstats: SWAP_STATS != SWAP_NSWAP");
 161                 }
 162
 163                 *total = 0;
 164                 *used = 0;
 165
 166                 for (i = 0; i < rnswap; i++) {
 167                         *total += sep->se_nblks >> 1;
 168                         *used += sep->se_inuse >> 1;
 169                 }
 170
 171                 free(fsep);
 172         }
 173
 174         const char *
 175         swap_free(void)
 176         {
 177                 int total, used;
 178
 179                 getstats(&total, &used);
 180
 181                 return fmt_human_2((total - used) * 1024, "B");
 182         }
 183
 184         const char *
 185         swap_perc(void)
 186         {
 187                 int total, used;
 188
 189                 getstats(&total, &used);
 190
 191                 if (total == 0) {
 192                         return NULL;
 193                 }
 194
 195                 return bprintf("%d%%", 100 * used / total);
 196         }
 197
 198         const char *
 199         swap_total(void)
 200         {
 201                 int total, used;
 202
 203                 getstats(&total, &used);
 204
 205                 return fmt_human_2(total * 1024, "B");
 206         }
 207
 208         const char *
 209         swap_used(void)
 210         {
 211                 int total, used;
 212
 213                 getstats(&total, &used);
 214
 215                 return fmt_human_2(used * 1024, "B");
 216         }
 217 #endif