X-Git-Url: https://git.xinqibao.xyz/slstatus.git/blobdiff_plain/35295f190207d9001fdcf30fe76f11434691b259..fcc5c683a6cb6efa380d82e6af34b31181ea1751:/slstatus.c?ds=inline

diff --git a/slstatus.c b/slstatus.c
index ada6441..f72f994 100644
--- a/slstatus.c
+++ b/slstatus.c
@@ -1,11 +1,11 @@
 /* See LICENSE file for copyright and license details. */
-
+#include <dirent.h>
 #include <err.h>
+#include <errno.h>
 #include <fcntl.h>
 #include <ifaddrs.h>
 #include <limits.h>
 #include <linux/wireless.h>
-#include <locale.h>
 #include <netdb.h>
 #include <pwd.h>
 #include <signal.h>
@@ -27,184 +27,205 @@
 
 #include "arg.h"
 
+#define LEN(x) (sizeof (x) / sizeof *(x))
+
 struct arg {
-	char *(*func)();
+	const char *(*func)();
 	const char *fmt;
 	const char *args;
 };
 
-static char *smprintf(const char *fmt, ...);
-static char *battery_perc(const char *bat);
-static char *battery_state(const char *bat);
-static char *cpu_perc(void);
-static char *datetime(const char *fmt);
-static char *disk_free(const char *mnt);
-static char *disk_perc(const char *mnt);
-static char *disk_total(const char *mnt);
-static char *disk_used(const char *mnt);
-static char *entropy(void);
-static char *gid(void);
-static char *hostname(void);
-static char *ip(const char *iface);
-static char *kernel_release(void);
-static char *keyboard_indicators(void);
-static char *load_avg(void);
-static char *ram_free(void);
-static char *ram_perc(void);
-static char *ram_used(void);
-static char *ram_total(void);
-static char *run_command(const char *cmd);
-static char *swap_free(void);
-static char *swap_perc(void);
-static char *swap_used(void);
-static char *swap_total(void);
-static char *temp(const char *file);
-static char *uid(void);
-static char *uptime(void);
-static char *username(void);
-static char *vol_perc(const char *card);
-static char *wifi_perc(const char *iface);
-static char *wifi_essid(const char *iface);
-static void sighandler(const int signo);
-static void usage(const int eval);
+static const char *battery_perc(const char *bat);
+static const char *battery_power(const char *bat);
+static const char *battery_state(const char *bat);
+static const char *cpu_freq(void);
+static const char *cpu_perc(void);
+static const char *datetime(const char *fmt);
+static const char *disk_free(const char *mnt);
+static const char *disk_perc(const char *mnt);
+static const char *disk_total(const char *mnt);
+static const char *disk_used(const char *mnt);
+static const char *entropy(void);
+static const char *gid(void);
+static const char *hostname(void);
+static const char *ip(const char *iface);
+static const char *kernel_release(void);
+static const char *keyboard_indicators(void);
+static const char *load_avg(void);
+static const char *num_files(const char *dir);
+static const char *ram_free(void);
+static const char *ram_perc(void);
+static const char *ram_used(void);
+static const char *ram_total(void);
+static const char *run_command(const char *cmd);
+static const char *swap_free(void);
+static const char *swap_perc(void);
+static const char *swap_used(void);
+static const char *swap_total(void);
+static const char *temp(const char *file);
+static const char *uid(void);
+static const char *uptime(void);
+static const char *username(void);
+static const char *vol_perc(const char *card);
+static const char *wifi_perc(const char *iface);
+static const char *wifi_essid(const char *iface);
 
 char *argv0;
-static unsigned short int delay = 0;
 static unsigned short int done;
-static unsigned short int dflag, oflag;
 static Display *dpy;
 
 #include "config.h"
 
-static char *
-smprintf(const char *fmt, ...)
+static char buf[MAXLEN];
+
+static const char *
+bprintf(const char *fmt, ...)
 {
 	va_list ap;
-	char *ret;
-	int len;
+	size_t len;
 
 	va_start(ap, fmt);
-	len = vsnprintf(NULL, 0, fmt, ap);
+	len = vsnprintf(buf, sizeof(buf) - 1, fmt, ap);
 	va_end(ap);
 
-	ret = malloc(++len);
-	if (ret == NULL) {
-		err(1, "malloc");
-	}
+	if (len >= sizeof(buf))
+		buf[sizeof(buf)-1] = '\0';
 
+	return buf;
+}
+
+int
+pscanf(const char *path, const char *fmt, ...)
+{
+	FILE *fp;
+	va_list ap;
+	int n;
+
+	if (!(fp = fopen(path, "r"))) {
+		warn("fopen %s: %s\n", path, strerror(errno));
+		return -1;
+	}
 	va_start(ap, fmt);
-	vsnprintf(ret, len, fmt, ap);
+	n = vfscanf(fp, fmt, ap);
 	va_end(ap);
+	fclose(fp);
 
-	return ret;
+	return (n == EOF) ? -1 : n;
 }
 
-static char *
+static const char *
 battery_perc(const char *bat)
 {
 	int perc;
 	char path[PATH_MAX];
-	FILE *fp;
 
 	snprintf(path, sizeof(path), "%s%s%s", "/sys/class/power_supply/", bat, "/capacity");
-	fp = fopen(path, "r");
-	if (fp == NULL) {
-		warn("Failed to open file %s", path);
-		return smprintf("%s", UNKNOWN_STR);
-	}
-	fscanf(fp, "%i", &perc);
-	fclose(fp);
+	return (pscanf(path, "%i", &perc) == 1) ?
+	       bprintf("%d", perc) : unknown_str;
+}
 
-	return smprintf("%d%%", perc);
+static 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) : unknown_str;
 }
 
-static char *
+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;
+	char path[PATH_MAX], state[12];
 
 	snprintf(path, sizeof(path), "%s%s%s", "/sys/class/power_supply/", bat, "/status");
-	fp = fopen(path, "r");
-	if (fp == NULL) {
-		warn("Failed to open file %s", path);
-		return smprintf("%s", UNKNOWN_STR);
+	if (pscanf(path, "%12s", state) != 1) {
+		return unknown_str;
 	}
-	fscanf(fp, "%12s", state);
-	fclose(fp);
 
-	if (strcmp(state, "Charging") == 0) {
-		return smprintf("+");
-	} else if (strcmp(state, "Discharging") == 0) {
-		return smprintf("-");
-	} else if (strcmp(state, "Full") == 0) {
-		return smprintf("=");
-	} else if (strcmp(state, "Unknown") == 0) {
-		return smprintf("/");
-	} else {
-		return smprintf("?");
+	for (i = 0; i < LEN(map); i++) {
+		if (!strcmp(map[i].state, state)) {
+			break;
+		}
 	}
+	return (i == LEN(map)) ? "?" : map[i].symbol;
+}
+
+static const char *
+cpu_freq(void)
+{
+	int freq;
+
+	return (pscanf("/sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq",
+	               "%i", &freq) == 1) ?
+	       bprintf("%d", (freq + 500) / 1000) : unknown_str;
 }
 
-static char *
+static const char *
 cpu_perc(void)
 {
+	struct timespec delay;
 	int perc;
 	long double a[4], b[4];
-	FILE *fp;
 
-	fp = fopen("/proc/stat", "r");
-	if (fp == NULL) {
-		warn("Failed to open file /proc/stat");
-		return smprintf("%s", UNKNOWN_STR);
+	if (pscanf("/proc/stat", "%*s %Lf %Lf %Lf %Lf", &a[0], &a[1], &a[2],
+	           &a[3]) != 4) {
+		return unknown_str;
 	}
-	fscanf(fp, "%*s %Lf %Lf %Lf %Lf", &a[0], &a[1], &a[2], &a[3]);
-	fclose(fp);
 
-	delay++;
-	sleep(delay);
+	delay.tv_sec = (interval / 2) / 1000;
+	delay.tv_nsec = ((interval / 2) % 1000) * 1000000;
+	nanosleep(&delay, NULL);
 
-	fp = fopen("/proc/stat", "r");
-	if (fp == NULL) {
-		warn("Failed to open file /proc/stat");
-		return smprintf("%s", UNKNOWN_STR);
+	if (pscanf("/proc/stat", "%*s %Lf %Lf %Lf %Lf", &b[0], &b[1], &b[2],
+	           &b[3]) != 4) {
+		return unknown_str;
 	}
-	fscanf(fp, "%*s %Lf %Lf %Lf %Lf", &b[0], &b[1], &b[2], &b[3]);
-	fclose(fp);
 
-	perc = 100 * ((b[0]+b[1]+b[2]) - (a[0]+a[1]+a[2])) / ((b[0]+b[1]+b[2]+b[3]) - (a[0]+a[1]+a[2]+a[3]));
-	return smprintf("%d%%", perc);
+	perc = 100 * ((b[0]+b[1]+b[2]) - (a[0]+a[1]+a[2])) /
+	       ((b[0]+b[1]+b[2]+b[3]) - (a[0]+a[1]+a[2]+a[3]));
+
+	return bprintf("%d", perc);
 }
 
-static char *
+static const char *
 datetime(const char *fmt)
 {
 	time_t t;
-	char str[80];
 
 	t = time(NULL);
-	if (strftime(str, sizeof(str), fmt, localtime(&t)) == 0) {
-		return smprintf("%s", UNKNOWN_STR);
-	}
+	if (strftime(buf, sizeof(buf), fmt, localtime(&t)) == 0)
+		return unknown_str;
 
-	return smprintf("%s", str);
+	return buf;
 }
 
-static char *
+static const char *
 disk_free(const char *mnt)
 {
 	struct statvfs fs;
 
 	if (statvfs(mnt, &fs) < 0) {
 		warn("Failed to get filesystem info");
-		return smprintf("%s", UNKNOWN_STR);
+		return unknown_str;
 	}
 
-	return smprintf("%f", (float)fs.f_bsize * (float)fs.f_bfree / 1024 / 1024 / 1024);
+	return bprintf("%f", (float)fs.f_bsize * (float)fs.f_bfree / 1024 / 1024 / 1024);
 }
 
-static char *
+static const char *
 disk_perc(const char *mnt)
 {
 	int perc;
@@ -212,77 +233,67 @@ disk_perc(const char *mnt)
 
 	if (statvfs(mnt, &fs) < 0) {
 		warn("Failed to get filesystem info");
-		return smprintf("%s", UNKNOWN_STR);
+		return unknown_str;
 	}
 
 	perc = 100 * (1.0f - ((float)fs.f_bfree / (float)fs.f_blocks));
 
-	return smprintf("%d%%", perc);
+	return bprintf("%d", perc);
 }
 
-static char *
+static const char *
 disk_total(const char *mnt)
 {
 	struct statvfs fs;
 
 	if (statvfs(mnt, &fs) < 0) {
 		warn("Failed to get filesystem info");
-		return smprintf("%s", UNKNOWN_STR);
+		return unknown_str;
 	}
 
-	return smprintf("%f", (float)fs.f_bsize * (float)fs.f_blocks / 1024 / 1024 / 1024);
+	return bprintf("%f", (float)fs.f_bsize * (float)fs.f_blocks / 1024 / 1024 / 1024);
 }
 
-static char *
+static const char *
 disk_used(const char *mnt)
 {
 	struct statvfs fs;
 
 	if (statvfs(mnt, &fs) < 0) {
 		warn("Failed to get filesystem info");
-		return smprintf("%s", UNKNOWN_STR);
+		return unknown_str;
 	}
 
-	return smprintf("%f", (float)fs.f_bsize * ((float)fs.f_blocks - (float)fs.f_bfree) / 1024 / 1024 / 1024);
+	return bprintf("%f", (float)fs.f_bsize * ((float)fs.f_blocks - (float)fs.f_bfree) / 1024 / 1024 / 1024);
 }
 
-static char *
+static const char *
 entropy(void)
 {
 	int num;
-	FILE *fp;
 
-	fp= fopen("/proc/sys/kernel/random/entropy_avail", "r");
-	if (fp == NULL) {
-		warn("Failed to open file /proc/sys/kernel/random/entropy_avail");
-		return smprintf("%s", UNKNOWN_STR);
-	}
-	fscanf(fp, "%d", &num);
-	fclose(fp);
-
-	return smprintf("%d", num);
+        return (pscanf("/proc/sys/kernel/random/entropy_avail", "%d", &num) == 1) ?
+	               bprintf("%d", num) : unknown_str;
 }
 
-static char *
+static const char *
 gid(void)
 {
-	return smprintf("%d", getgid());
+	return bprintf("%d", getgid());
 }
 
-static char *
+static const char *
 hostname(void)
 {
-	char buf[HOST_NAME_MAX];
-
 	if (gethostname(buf, sizeof(buf)) == -1) {
 		warn("hostname");
-		return smprintf("%s", UNKNOWN_STR);
+		return unknown_str;
 	}
 
-	return smprintf("%s", buf);
+	return buf;
 }
 
-static char *
+static const char *
 ip(const char *iface)
 {
 	struct ifaddrs *ifaddr, *ifa;
@@ -291,7 +302,7 @@ ip(const char *iface)
 
 	if (getifaddrs(&ifaddr) == -1) {
 		warn("Failed to get IP address for interface %s", iface);
-		return smprintf("%s", UNKNOWN_STR);
+		return unknown_str;
 	}
 
 	for (ifa = ifaddr; ifa != NULL; ifa = ifa->ifa_next) {
@@ -302,331 +313,299 @@ ip(const char *iface)
 		if ((strcmp(ifa->ifa_name, iface) == 0) && (ifa->ifa_addr->sa_family == AF_INET)) {
 			if (s != 0) {
 				warnx("Failed to get IP address for interface %s", iface);
-				return smprintf("%s", UNKNOWN_STR);
+				return unknown_str;
 			}
-			return smprintf("%s", host);
+			return bprintf("%s", host);
 		}
 	}
 
 	freeifaddrs(ifaddr);
 
-	return smprintf("%s", UNKNOWN_STR);
+	return unknown_str;
 }
 
-static char *
+static const char *
 kernel_release(void)
 {
 	struct utsname udata;
 
 	if (uname(&udata) < 0) {
-		return smprintf(UNKNOWN_STR);
+		return unknown_str;
 	}
 
-	return smprintf("%s", udata.release);
+	return bprintf("%s", udata.release);
 }
 
-static char *
+static const char *
 keyboard_indicators(void)
 {
 	Display *dpy = XOpenDisplay(NULL);
 	XKeyboardState state;
+
+	if (dpy == NULL) {
+		warnx("XOpenDisplay failed");
+		return unknown_str;
+	}
 	XGetKeyboardControl(dpy, &state);
 	XCloseDisplay(dpy);
 
 	switch (state.led_mask) {
 		case 1:
-			return smprintf("c");
-			break;
+			return "c";
 		case 2:
-			return smprintf("n");
-			break;
+			return "n";
 		case 3:
-			return smprintf("cn");
-			break;
+			return "cn";
 		default:
-			return smprintf("");
+			return "";
 	}
 }
 
-static char *
+static const char *
 load_avg(void)
 {
 	double avgs[3];
 
 	if (getloadavg(avgs, 3) < 0) {
 		warnx("Failed to get the load avg");
-		return smprintf("%s", UNKNOWN_STR);
+		return unknown_str;
 	}
 
-	return smprintf("%.2f %.2f %.2f", avgs[0], avgs[1], avgs[2]);
+	return bprintf("%.2f %.2f %.2f", avgs[0], avgs[1], avgs[2]);
 }
 
-static char *
-ram_free(void)
+static const char *
+num_files(const char *dir)
 {
-	long free;
-	FILE *fp;
+	struct dirent *dp;
+	DIR *fd;
+	int num = 0;
 
-	fp = fopen("/proc/meminfo", "r");
-	if (fp == NULL) {
-		warn("Failed to open file /proc/meminfo");
-		return smprintf("%s", UNKNOWN_STR);
+	if ((fd = opendir(dir)) == NULL) {
+		warn("Failed to get number of files in directory %s", dir);
+		return unknown_str;
 	}
-	fscanf(fp, "MemFree: %ld kB\n", &free);
-	fclose(fp);
 
-	return smprintf("%f", (float)free / 1024 / 1024);
+	while ((dp = readdir(fd)) != NULL) {
+		if (!strcmp(dp->d_name, ".") || !strcmp(dp->d_name, ".."))
+			continue; /* skip self and parent */
+		num++;
+	}
+
+	closedir(fd);
+
+	return bprintf("%d", num);
 }
 
-static char *
+static const char *
+ram_free(void)
+{
+	long free;
+
+	return (pscanf("/proc/meminfo", "MemFree: %ld kB\n", &free) == 1) ?
+	       bprintf("%f", (float)free / 1024 / 1024) : unknown_str;
+}
+
+static const char *
 ram_perc(void)
 {
 	long total, free, buffers, cached;
-	FILE *fp;
 
-	fp = fopen("/proc/meminfo", "r");
-	if (fp == NULL) {
-		warn("Failed to open file /proc/meminfo");
-		return smprintf("%s", UNKNOWN_STR);
-	}
-	fscanf(fp, "MemTotal: %ld kB\n", &total);
-	fscanf(fp, "MemFree: %ld kB\n", &free);
-	fscanf(fp, "MemAvailable: %ld kB\nBuffers: %ld kB\n", &buffers, &buffers);
-	fscanf(fp, "Cached: %ld kB\n", &cached);
-	fclose(fp);
-
-	return smprintf("%d%%", 100 * ((total - free) - (buffers + cached)) / total);
+	return (pscanf("/proc/meminfo",
+	               "MemTotal: %ld kB\n"
+	               "MemFree: %ld kB\n"
+	               "MemAvailable: %ld kB\nBuffers: %ld kB\n"
+	               "Cached: %ld kB\n",
+	               &total, &free, &buffers, &buffers, &cached) == 5) ?
+	       bprintf("%d", 100 * ((total - free) - (buffers + cached)) / total) :
+	       unknown_str;
 }
 
-static char *
+static const char *
 ram_total(void)
 {
 	long total;
-	FILE *fp;
 
-	fp = fopen("/proc/meminfo", "r");
-	if (fp == NULL) {
-		warn("Failed to open file /proc/meminfo");
-		return smprintf("%s", UNKNOWN_STR);
-	}
-	fscanf(fp, "MemTotal: %ld kB\n", &total);
-	fclose(fp);
-
-	return smprintf("%f", (float)total / 1024 / 1024);
+	return (pscanf("/proc/meminfo", "MemTotal: %ld kB\n", &total) == 1) ?
+	       bprintf("%f", (float)total / 1024 / 1024) : unknown_str;
 }
 
-static char *
+static const char *
 ram_used(void)
 {
-	long free, total, buffers, cached;
-	FILE *fp;
-
-	fp = fopen("/proc/meminfo", "r");
-	if (fp == NULL) {
-		warn("Failed to open file /proc/meminfo");
-		return smprintf("%s", UNKNOWN_STR);
-	}
-	fscanf(fp, "MemTotal: %ld kB\n", &total);
-	fscanf(fp, "MemFree: %ld kB\n", &free);
-	fscanf(fp, "MemAvailable: %ld kB\nBuffers: %ld kB\n", &buffers, &buffers);
-	fscanf(fp, "Cached: %ld kB\n", &cached);
-	fclose(fp);
+	long total, free, buffers, cached;
 
-	return smprintf("%f", (float)(total - free - buffers - cached) / 1024 / 1024);
+	return (pscanf("/proc/meminfo",
+	               "MemTotal: %ld kB\n"
+	               "MemFree: %ld kB\n"
+	               "MemAvailable: %ld kB\nBuffers: %ld kB\n"
+	               "Cached: %ld kB\n",
+	               &total, &free, &buffers, &buffers, &cached) == 5) ?
+	       bprintf("%f", (float)(total - free - buffers - cached) / 1024 / 1024) :
+	       unknown_str;
 }
 
-static char *
+static const char *
 run_command(const char *cmd)
 {
-	char *nlptr;
+	char *p;
 	FILE *fp;
-	char buf[1024] = UNKNOWN_STR;
 
 	fp = popen(cmd, "r");
 	if (fp == NULL) {
 		warn("Failed to get command output for %s", cmd);
-		return smprintf("%s", UNKNOWN_STR);
+		return unknown_str;
 	}
-	fgets(buf, sizeof(buf), fp);
+	p = fgets(buf, sizeof(buf) - 1, fp);
 	pclose(fp);
-	buf[sizeof(buf) - 1] = '\0';
-
-	if ((nlptr = strstr(buf, "\n")) != NULL) {
-		nlptr[0] = '\0';
-	}
+	if (!p)
+		return unknown_str;
+	if ((p = strrchr(buf, '\n')) != NULL)
+		p[0] = '\0';
 
-	return smprintf("%s", buf);
+	return buf[0] ? buf : unknown_str;
 }
 
-static char *
+static const char *
 swap_free(void)
 {
 	long total, free;
 	FILE *fp;
-	char buf[2048];
 	size_t bytes_read;
 	char *match;
 
 	fp = fopen("/proc/meminfo", "r");
 	if (fp == NULL) {
 		warn("Failed to open file /proc/meminfo");
-		return smprintf("%s", UNKNOWN_STR);
+		return unknown_str;
 	}
 
 	if ((bytes_read = fread(buf, sizeof(char), sizeof(buf) - 1, fp)) == 0) {
 		warn("swap_free: read error");
 		fclose(fp);
-		return smprintf("%s", UNKNOWN_STR);
+		return unknown_str;
 	}
-
-	buf[bytes_read] = '\0';
 	fclose(fp);
 
-	if ((match = strstr(buf, "SwapTotal")) == NULL) {
-		return smprintf("%s", UNKNOWN_STR);
-	}
+	if ((match = strstr(buf, "SwapTotal")) == NULL)
+		return unknown_str;
 	sscanf(match, "SwapTotal: %ld kB\n", &total);
 
-	if ((match = strstr(buf, "SwapFree")) == NULL) {
-		return smprintf("%s", UNKNOWN_STR);
-	}
+	if ((match = strstr(buf, "SwapFree")) == NULL)
+		return unknown_str;
 	sscanf(match, "SwapFree: %ld kB\n", &free);
 
-	return smprintf("%f", (float)free / 1024 / 1024);
+	return bprintf("%f", (float)free / 1024 / 1024);
 }
 
-static char *
+static const char *
 swap_perc(void)
 {
 	long total, free, cached;
 	FILE *fp;
-	char buf[2048];
 	size_t bytes_read;
 	char *match;
 
 	fp = fopen("/proc/meminfo", "r");
 	if (fp == NULL) {
 		warn("Failed to open file /proc/meminfo");
-		return smprintf("%s", UNKNOWN_STR);
+		return unknown_str;
 	}
 
 	if ((bytes_read = fread(buf, sizeof(char), sizeof(buf) - 1, fp)) == 0) {
 		warn("swap_perc: read error");
 		fclose(fp);
-		return smprintf("%s", UNKNOWN_STR);
+		return unknown_str;
 	}
-
-	buf[bytes_read] = '\0';
 	fclose(fp);
 
-	if ((match = strstr(buf, "SwapTotal")) == NULL) {
-		return smprintf("%s", UNKNOWN_STR);
-	}
+	if ((match = strstr(buf, "SwapTotal")) == NULL)
+		return unknown_str;
 	sscanf(match, "SwapTotal: %ld kB\n", &total);
 
-	if ((match = strstr(buf, "SwapCached")) == NULL) {
-		return smprintf("%s", UNKNOWN_STR);
-	}
+	if ((match = strstr(buf, "SwapCached")) == NULL)
+		return unknown_str;
 	sscanf(match, "SwapCached: %ld kB\n", &cached);
 
-	if ((match = strstr(buf, "SwapFree")) == NULL) {
-		return smprintf("%s", UNKNOWN_STR);
-	}
+	if ((match = strstr(buf, "SwapFree")) == NULL)
+		return unknown_str;
 	sscanf(match, "SwapFree: %ld kB\n", &free);
 
-	return smprintf("%d%%", 100 * (total - free - cached) / total);
+	return bprintf("%d", 100 * (total - free - cached) / total);
 }
 
-static char *
+static const char *
 swap_total(void)
 {
 	long total;
 	FILE *fp;
-	char buf[2048];
 	size_t bytes_read;
 	char *match;
 
 	fp = fopen("/proc/meminfo", "r");
 	if (fp == NULL) {
 		warn("Failed to open file /proc/meminfo");
-		return smprintf("%s", UNKNOWN_STR);
+		return unknown_str;
 	}
 	if ((bytes_read = fread(buf, sizeof(char), sizeof(buf) - 1, fp)) == 0) {
 		warn("swap_total: read error");
 		fclose(fp);
-		return smprintf("%s", UNKNOWN_STR);
+		return unknown_str;
 	}
-
-	buf[bytes_read] = '\0';
 	fclose(fp);
 
-	if ((match = strstr(buf, "SwapTotal")) == NULL) {
-		return smprintf("%s", UNKNOWN_STR);
-	}
+	if ((match = strstr(buf, "SwapTotal")) == NULL)
+		return unknown_str;
 	sscanf(match, "SwapTotal: %ld kB\n", &total);
 
-	return smprintf("%f", (float)total / 1024 / 1024);
+	return bprintf("%f", (float)total / 1024 / 1024);
 }
 
-static char *
+static const char *
 swap_used(void)
 {
 	long total, free, cached;
 	FILE *fp;
-	char buf[2048];
 	size_t bytes_read;
 	char *match;
 
 	fp = fopen("/proc/meminfo", "r");
 	if (fp == NULL) {
 		warn("Failed to open file /proc/meminfo");
-		return smprintf("%s", UNKNOWN_STR);
+		return unknown_str;
 	}
 	if ((bytes_read = fread(buf, sizeof(char), sizeof(buf) - 1, fp)) == 0) {
 		warn("swap_used: read error");
 		fclose(fp);
-		return smprintf("%s", UNKNOWN_STR);
+		return unknown_str;
 	}
-
-	buf[bytes_read] = '\0';
 	fclose(fp);
 
-	if ((match = strstr(buf, "SwapTotal")) == NULL) {
-		return smprintf("%s", UNKNOWN_STR);
-	}
+	if ((match = strstr(buf, "SwapTotal")) == NULL)
+		return unknown_str;
 	sscanf(match, "SwapTotal: %ld kB\n", &total);
 
-	if ((match = strstr(buf, "SwapCached")) == NULL) {
-		return smprintf("%s", UNKNOWN_STR);
-	}
+	if ((match = strstr(buf, "SwapCached")) == NULL)
+		return unknown_str;
 	sscanf(match, "SwapCached: %ld kB\n", &cached);
 
-	if ((match = strstr(buf, "SwapFree")) == NULL) {
-		return smprintf("%s", UNKNOWN_STR);
-	}
+	if ((match = strstr(buf, "SwapFree")) == NULL)
+		return unknown_str;
 	sscanf(match, "SwapFree: %ld kB\n", &free);
 
-	return smprintf("%f", (float)(total - free - cached) / 1024 / 1024);
+	return bprintf("%f", (float)(total - free - cached) / 1024 / 1024);
 }
 
-static char *
+static const char *
 temp(const char *file)
 {
 	int temp;
-	FILE *fp;
-
-	fp = fopen(file, "r");
-	if (fp == NULL) {
-		warn("Failed to open file %s", file);
-		return smprintf("%s", UNKNOWN_STR);
-	}
-	fscanf(fp, "%d", &temp);
-	fclose(fp);
 
-	return smprintf("%d°C", temp / 1000);
+	return (pscanf(file, "%d", &temp) == 1) ?
+	       bprintf("%d", temp / 1000) : unknown_str;
 }
 
-static char *
+static const char *
 uptime(void)
 {
 	struct sysinfo info;
@@ -637,63 +616,67 @@ uptime(void)
 	h = info.uptime / 3600;
 	m = (info.uptime - h * 3600 ) / 60;
 
-	return smprintf("%dh %dm", h, m);
+	return bprintf("%dh %dm", h, m);
 }
 
-static char *
+static const char *
 username(void)
 {
-	uid_t uid = geteuid();
-	struct passwd *pw = getpwuid(uid);
+	struct passwd *pw = getpwuid(geteuid());
 
 	if (pw == NULL) {
 		warn("Failed to get username");
-		return smprintf("%s", UNKNOWN_STR);
+		return unknown_str;
 	}
 
-	return smprintf("%s", pw->pw_name);
+	return bprintf("%s", pw->pw_name);
 }
 
-static char *
+static const char *
 uid(void)
 {
-	return smprintf("%d", geteuid());
+	return bprintf("%d", geteuid());
 }
 
 
-static char *
+static const char *
 vol_perc(const char *card)
 {
 	unsigned int i;
 	int v, afd, devmask;
 	char *vnames[] = SOUND_DEVICE_NAMES;
 
-	afd = open(card, O_RDONLY);
-	if (afd < 0) {
+	afd = open(card, O_RDONLY | O_NONBLOCK);
+	if (afd == -1) {
 		warn("Cannot open %s", card);
-		return smprintf(UNKNOWN_STR);
+		return unknown_str;
 	}
 
-	ioctl(afd, MIXER_READ(SOUND_MIXER_DEVMASK), &devmask);
-	for (i = 0; i < (sizeof(vnames) / sizeof((vnames[0]))); i++) {
-		if (devmask & (1 << i)) {
-			if (!strcmp("vol", vnames[i])) {
-				ioctl(afd, MIXER_READ(i), &v);
+	if (ioctl(afd, SOUND_MIXER_READ_DEVMASK, &devmask) == -1) {
+		warn("Cannot get volume for %s", card);
+		close(afd);
+		return unknown_str;
+	}
+	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");
+				close(afd);
+				return unknown_str;
 			}
 		}
 	}
 
 	close(afd);
 
-	return smprintf("%d%%", v & 0xff);
+	return bprintf("%d", v & 0xff);
 }
 
-static char *
+static const char *
 wifi_perc(const char *iface)
 {
-	int perc;
-	char buf[255];
-	char *datastart;
+	int i, perc;
+	char *p, *datastart;
 	char path[PATH_MAX];
 	char status[5];
 	FILE *fp;
@@ -702,38 +685,41 @@ wifi_perc(const char *iface)
 	fp = fopen(path, "r");
 	if (fp == NULL) {
 		warn("Failed to open file %s", path);
-		return smprintf("%s", UNKNOWN_STR);
+		return unknown_str;
 	}
-	fgets(status, 5, fp);
+	p = fgets(status, 5, fp);
 	fclose(fp);
-	if(strcmp(status, "up\n") != 0) {
-		return smprintf("%s", UNKNOWN_STR);
+	if(!p || strcmp(status, "up\n") != 0) {
+		return unknown_str;
 	}
 
 	fp = fopen("/proc/net/wireless", "r");
 	if (fp == NULL) {
 		warn("Failed to open file /proc/net/wireless");
-		return smprintf("%s", UNKNOWN_STR);
+		return unknown_str;
 	}
 
-	fgets(buf, sizeof(buf), fp);
-	fgets(buf, sizeof(buf), fp);
-	fgets(buf, sizeof(buf), fp);
+	for (i = 0; i < 3; i++) {
+		if (!(p = fgets(buf, sizeof(buf) - 1, fp)))
+			break;
+	}
 	fclose(fp);
+	if (i < 2 || !p)
+		return unknown_str;
+
+	if ((datastart = strstr(buf, iface)) == NULL)
+		return unknown_str;
 
-	if ((datastart = strstr(buf, iface)) == NULL) {
-		return smprintf("%s", UNKNOWN_STR);
-	}
 	datastart = (datastart+(strlen(iface)+1));
 	sscanf(datastart + 1, " %*d   %d  %*d  %*d		  %*d	   %*d		%*d		 %*d	  %*d		 %*d", &perc);
 
-	return smprintf("%d%%", perc);
+	return bprintf("%d", perc);
 }
 
-static char *
+static const char *
 wifi_essid(const char *iface)
 {
-	char id[IW_ESSID_MAX_SIZE+1];
+	static char id[IW_ESSID_MAX_SIZE+1];
 	int sockfd = socket(AF_INET, SOCK_DGRAM, 0);
 	struct iwreq wreq;
 
@@ -743,117 +729,109 @@ wifi_essid(const char *iface)
 
 	if (sockfd == -1) {
 		warn("Failed to get ESSID for interface %s", iface);
-		return smprintf("%s", UNKNOWN_STR);
+		return unknown_str;
 	}
 	wreq.u.essid.pointer = id;
 	if (ioctl(sockfd,SIOCGIWESSID, &wreq) == -1) {
 		warn("Failed to get ESSID for interface %s", iface);
-		return smprintf("%s", UNKNOWN_STR);
+		return unknown_str;
 	}
 
 	close(sockfd);
 
-	if (strcmp((char *)wreq.u.essid.pointer, "") == 0)
-		return smprintf("%s", UNKNOWN_STR);
+	if (strcmp(id, "") == 0)
+		return unknown_str;
 	else
-		return smprintf("%s", (char *)wreq.u.essid.pointer);
+		return id;
 }
 
 static void
-sighandler(const int signo)
+terminate(const int signo)
 {
-	if (signo == SIGTERM || signo == SIGINT) {
-		done = 1;
-	}
+	done = 1;
 }
 
 static void
-usage(const int eval)
+difftimespec(struct timespec *res, struct timespec *a, struct timespec *b)
 {
-	fprintf(stderr, "usage: %s [-d] [-o] [-v] [-h]\n", argv0);
-	exit(eval);
+	res->tv_sec = a->tv_sec - b->tv_sec - (a->tv_nsec < b->tv_nsec);
+	res->tv_nsec = a->tv_nsec - b->tv_nsec +
+	               (a->tv_nsec < b->tv_nsec) * 1000000000;
+}
+
+static void
+usage(void)
+{
+	fprintf(stderr, "usage: %s [-s]\n", argv0);
+	exit(1);
 }
 
 int
 main(int argc, char *argv[])
 {
-	unsigned short int i;
-	char status_string[2048];
-	char *res, *element;
-	struct arg argument;
 	struct sigaction act;
+	struct timespec start, current, diff, intspec, wait;
+	size_t i, len;
+	int sflag = 0;
+	char status[MAXLEN];
 
 	ARGBEGIN {
-		case 'd':
-			dflag = 1;
-			break;
-		case 'o':
-			oflag = 1;
+		case 's':
+			sflag = 1;
 			break;
-		case 'v':
-			printf("slstatus (C) 2016-2017 slstatus engineers\n");
-			return 0;
-		case 'h':
-			usage(0);
 		default:
-			usage(1);
+			usage();
 	} ARGEND
 
-	if (dflag && oflag) {
-		usage(1);
-	}
-	if (dflag && daemon(1, 1) < 0) {
-		err(1, "daemon");
+	if (argc) {
+		usage();
 	}
 
 	memset(&act, 0, sizeof(act));
-	act.sa_handler = sighandler;
-	sigaction(SIGINT,  &act, 0);
-	sigaction(SIGTERM, &act, 0);
+	act.sa_handler = terminate;
+	sigaction(SIGINT,  &act, NULL);
+	sigaction(SIGTERM, &act, NULL);
 
-	if (!oflag) {
-		dpy = XOpenDisplay(NULL);
+	if (!sflag && !(dpy = XOpenDisplay(NULL))) {
+		fprintf(stderr, "slstatus: cannot open display");
+		return 1;
 	}
 
-	setlocale(LC_ALL, "");
-
 	while (!done) {
-		status_string[0] = '\0';
-
-		for (i = 0; i < sizeof(args) / sizeof(args[0]); ++i) {
-			argument = args[i];
-			if (argument.args == NULL) {
-				res = argument.func();
-			} else {
-				res = argument.func(argument.args);
-			}
-			element = smprintf(argument.fmt, res);
-			if (element == NULL) {
-				element = smprintf("%s", UNKNOWN_STR);
-				warnx("Failed to format output");
+		clock_gettime(CLOCK_MONOTONIC, &start);
+
+		status[0] = '\0';
+		for (i = len = 0; i < LEN(args); i++) {
+			len += snprintf(status + len, sizeof(status) - len,
+			                args[i].fmt, args[i].func(args[i].args));
+
+			if (len >= sizeof(status)) {
+				status[sizeof(status) - 1] = '\0';
 			}
-			strncat(status_string, element, sizeof(status_string) - strlen(status_string) - 1);
-			free(res);
-			free(element);
 		}
 
-		if (!oflag) {
-			XStoreName(dpy, DefaultRootWindow(dpy), status_string);
-			XSync(dpy, False);
+		if (sflag) {
+			printf("%s\n", status);
 		} else {
-			printf("%s\n", status_string);
+			XStoreName(dpy, DefaultRootWindow(dpy), status);
+			XSync(dpy, False);
 		}
 
-		if ((UPDATE_INTERVAL - delay) <= 0) {
-			delay = 0;
-			continue;
-		} else {
-			sleep(UPDATE_INTERVAL - delay);
-			delay = 0;
+		if (!done) {
+			clock_gettime(CLOCK_MONOTONIC, &current);
+			difftimespec(&diff, &current, &start);
+
+			intspec.tv_sec = interval / 1000;
+			intspec.tv_nsec = (interval % 1000) * 1000000;
+			difftimespec(&wait, &intspec, &diff);
+
+			if (wait.tv_sec >= 0) {
+				nanosleep(&wait, NULL);
+			}
 		}
 	}
 
-	if (!oflag) {
+	if (!sflag) {
 		XStoreName(dpy, DefaultRootWindow(dpy), NULL);
 		XCloseDisplay(dpy);
 	}