Xinqi Bao's Git

battery_remaining: check for division by zero
[slstatus.git] / components / battery.c
index aef5b5f..8bfe42a 100644 (file)
 /* See LICENSE file for copyright and license details. */
-#include <err.h>
+#include <errno.h>
 #include <stdio.h>
-#if defined(__linux__)
-#include <limits.h>
 #include <string.h>
-#elif defined(__OpenBSD__)
-#include <sys/ioctl.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <machine/apmvar.h>
-#endif
 
 #include "../util.h"
 
-const char *
-battery_perc(const char *bat)
-{
 #if defined(__linux__)
-       int perc;
-       char path[PATH_MAX];
+       #include <limits.h>
+       #include <unistd.h>
 
-       snprintf(path, sizeof(path), "%s%s%s", "/sys/class/power_supply/", bat, "/capacity");
-       return (pscanf(path, "%i", &perc) == 1) ?
-              bprintf("%d", perc) : NULL;
-#elif defined(__OpenBSD__)
-       struct apm_power_info apm_info;
-       int fd;
+       #define CHARGE_NOW "/sys/class/power_supply/%s/charge_now"
+       #define ENERGY_NOW "/sys/class/power_supply/%s/energy_now"
+       #define CURRENT_NOW "/sys/class/power_supply/%s/current_now"
+       #define POWER_NOW "/sys/class/power_supply/%s/power_now"
+
+       static const char *
+       pick(const char *bat, const char *f1, const char *f2, char *path,
+            size_t length)
+       {
+               if (esnprintf(path, length, f1, bat) > 0 &&
+                   access(path, R_OK) == 0) {
+                       return f1;
+               }
+
+               if (esnprintf(path, length, f2, bat) > 0 &&
+                   access(path, R_OK) == 0) {
+                       return f2;
+               }
 
-       fd = open("/dev/apm", O_RDONLY);
-       if (fd < 0) {
-               warn("Failed to open file /dev/apm");
                return NULL;
        }
 
-       if (ioctl(fd, APM_IOC_GETPOWER, &apm_info) < 0) {
-               warn("Failed to get battery info");
-               close(fd);
+       const char *
+       battery_perc(const char *bat)
+       {
+               int perc;
+               char path[PATH_MAX];
+
+               if (esnprintf(path, sizeof(path),
+                             "/sys/class/power_supply/%s/capacity",
+                             bat) < 0) {
+                       return NULL;
+               }
+               if (pscanf(path, "%d", &perc) != 1) {
+                       return NULL;
+               }
+
+               return bprintf("%d", perc);
+       }
+
+       const char *
+       battery_state(const char *bat)
+       {
+               static struct {
+                       char *state;
+                       char *symbol;
+               } map[] = {
+                       { "Charging",    "+" },
+                       { "Discharging", "-" },
+               };
+               size_t i;
+               char path[PATH_MAX], state[12];
+
+               if (esnprintf(path, sizeof(path),
+                             "/sys/class/power_supply/%s/status",
+                             bat) < 0) {
+                       return NULL;
+               }
+               if (pscanf(path, "%12s", state) != 1) {
+                       return NULL;
+               }
+
+               for (i = 0; i < LEN(map); i++) {
+                       if (!strcmp(map[i].state, state)) {
+                               break;
+                       }
+               }
+               return (i == LEN(map)) ? "?" : map[i].symbol;
+       }
+
+       const char *
+       battery_remaining(const char *bat)
+       {
+               int charge_now, current_now, m, h;
+               double timeleft;
+               char path[PATH_MAX], state[12];
+
+               if (esnprintf(path, sizeof(path),
+                             "/sys/class/power_supply/%s/status",
+                             bat) < 0) {
+                       return NULL;
+               }
+               if (pscanf(path, "%12s", state) != 1) {
+                       return NULL;
+               }
+
+               if (!pick(bat, CHARGE_NOW, ENERGY_NOW, path, sizeof(path)) ||
+                   pscanf(path, "%d", &charge_now) < 0) {
+                       return NULL;
+               }
+
+               if (!strcmp(state, "Discharging")) {
+                       if (!pick(bat, CURRENT_NOW, POWER_NOW, path,
+                                 sizeof(path)) ||
+                           pscanf(path, "%d", &current_now) < 0) {
+                               return NULL;
+                       }
+
+                       if (current_now == 0) {
+                               return NULL;
+                       }
+
+                       timeleft = (double)charge_now / (double)current_now;
+                       h = timeleft;
+                       m = (timeleft - (double)h) * 60;
+
+                       return bprintf("%dh %dm", h, m);
+               }
+
+               return "";
+       }
+#elif defined(__OpenBSD__)
+       #include <fcntl.h>
+       #include <machine/apmvar.h>
+       #include <sys/ioctl.h>
+       #include <unistd.h>
+
+       static int
+       load_apm_power_info(struct apm_power_info *apm_info)
+       {
+               int fd;
+
+               fd = open("/dev/apm", O_RDONLY);
+               if (fd < 0) {
+                       warn("open '/dev/apm':");
+                       return 0;
+               }
+
+               memset(apm_info, 0, sizeof(struct apm_power_info));
+               if (ioctl(fd, APM_IOC_GETPOWER, apm_info) < 0) {
+                       warn("ioctl 'APM_IOC_GETPOWER':");
+                       close(fd);
+                       return 0;
+               }
+               return close(fd), 1;
+       }
+
+       const char *
+       battery_perc(const char *unused)
+       {
+               struct apm_power_info apm_info;
+
+               if (load_apm_power_info(&apm_info)) {
+                       return bprintf("%d", apm_info.battery_life);
+               }
+
                return NULL;
        }
-       close(fd);
 
-       return bprintf("%d", apm_info.battery_life);
-#endif
-}
+       const char *
+       battery_state(const char *unused)
+       {
+               struct {
+                       unsigned int state;
+                       char *symbol;
+               } map[] = {
+                       { APM_AC_ON,      "+" },
+                       { APM_AC_OFF,     "-" },
+               };
+               struct apm_power_info apm_info;
+               size_t i;
+
+               if (load_apm_power_info(&apm_info)) {
+                       for (i = 0; i < LEN(map); i++) {
+                               if (map[i].state == apm_info.ac_state) {
+                                       break;
+                               }
+                       }
+                       return (i == LEN(map)) ? "?" : map[i].symbol;
+               }
 
-#if defined(__linux__)
-const char *
-battery_power(const char *bat)
-{
-       int watts;
-       char path[PATH_MAX];
-
-       snprintf(path, sizeof(path), "%s%s%s", "/sys/class/power_supply/", bat, "/power_now");
-       return (pscanf(path, "%i", &watts) == 1) ?
-              bprintf("%d", (watts + 500000) / 1000000) : NULL;
-}
-
-const char *
-battery_state(const char *bat)
-{
-       struct {
-               char *state;
-               char *symbol;
-       } map[] = {
-               { "Charging",    "+" },
-               { "Discharging", "-" },
-               { "Full",        "=" },
-               { "Unknown",     "/" },
-       };
-       size_t i;
-       char path[PATH_MAX], state[12];
-
-       snprintf(path, sizeof(path), "%s%s%s", "/sys/class/power_supply/", bat, "/status");
-       if (pscanf(path, "%12s", state) != 1) {
                return NULL;
        }
 
-       for (i = 0; i < LEN(map); i++) {
-               if (!strcmp(map[i].state, state)) {
-                       break;
+       const char *
+       battery_remaining(const char *unused)
+       {
+               struct apm_power_info apm_info;
+
+               if (load_apm_power_info(&apm_info)) {
+                       if (apm_info.ac_state != APM_AC_ON) {
+                               return bprintf("%uh %02um",
+                                              apm_info.minutes_left / 60,
+                                              apm_info.minutes_left % 60);
+                       } else {
+                               return "";
+                       }
                }
+
+               return NULL;
        }
-       return (i == LEN(map)) ? "?" : map[i].symbol;
-}
 #endif