Add and use LEN() macro

[slstatus.git] / slstatus.c

diff --git a/slstatus.c b/slstatus.c
index 4b6770b..596d6a6 100644 (file)
--- a/slstatus.c
+++ b/slstatus.c
@@ -28,6 +28,8 @@
 
 #include "arg.h"
 
+#define LEN(x) (sizeof (x) / sizeof *(x))
+
 struct arg {
        const char *(*func)();
        const char *fmt;
@@ -142,10 +144,19 @@ battery_power(const char *bat)
 static const char *
 battery_state(const char *bat)
 {
-       char path[PATH_MAX];
-       char state[12];
        FILE *fp;
+       struct {
+               char *state;
+               char *symbol;
+       } map[] = {
+               { "Charging",    "+" },
+               { "Discharging", "-" },
+               { "Full",        "=" },
+               { "Unknown",     "/" },
+       };
+       size_t i;
        int n;
+       char path[PATH_MAX], state[12];
 
        snprintf(path, sizeof(path), "%s%s%s", "/sys/class/power_supply/", bat, "/status");
        fp = fopen(path, "r");
@@ -158,17 +169,13 @@ battery_state(const char *bat)
        if (n != 1)
                return UNKNOWN_STR;
 
-       if (strcmp(state, "Charging") == 0) {
-               return "+";
-       } else if (strcmp(state, "Discharging") == 0) {
-               return "-";
-       } else if (strcmp(state, "Full") == 0) {
-               return "=";
-       } else if (strcmp(state, "Unknown") == 0) {
-               return "/";
-       } else {
-               return "?";
+       for (i = 0; i < LEN(map); i++) {
+               if (!strcmp(map[i].state, state)) {
+                       break;
+               }
        }
+
+       return (i == LEN(map)) ? "?" : map[i].symbol;
 }
 
 static const char *
@@ -740,7 +747,7 @@ vol_perc(const char *card)
                close(afd);
                return UNKNOWN_STR;
        }
-       for (i = 0; i < (sizeof(vnames) / sizeof((vnames[0]))); i++) {
+       for (i = 0; i < LEN(vnames); i++) {
                if (devmask & (1 << i) && !strcmp("vol", vnames[i])) {
                        if (ioctl(afd, MIXER_READ(i), &v) == -1) {
                                warn("vol_perc: ioctl");
@@ -861,6 +868,10 @@ main(int argc, char *argv[])
                        usage();
        } ARGEND
 
+       if (argc) {
+               usage();
+       }
+
        memset(&act, 0, sizeof(act));
        act.sa_handler = sighandler;
        sigaction(SIGINT,  &act, 0);
@@ -875,8 +886,7 @@ main(int argc, char *argv[])
        while (!done) {
                status_string[0] = '\0';
 
-               for (element = status_string, i = len = 0;
-                    i < sizeof(args) / sizeof(args[0]);
+               for (element = status_string, i = len = 0; i < LEN(args);
                     ++i, element += len) {
                        argument = args[i];
                        len = snprintf(element, sizeof(status_string)-1 - len,