X-Git-Url: https://git.xinqibao.xyz/slstatus.git/blobdiff_plain/5295629c4fe987ee51fcfdd380c86e3e0d5de5b5..ad8ab20c638998f71e9eb01c54820231db9a1079:/slstatus.c

diff --git a/slstatus.c b/slstatus.c
index 658bc79..08bbebb 100644
--- a/slstatus.c
+++ b/slstatus.c
@@ -2,353 +2,742 @@
 
 /* global libraries */
 #include <alsa/asoundlib.h>
+#include <arpa/inet.h>
+#include <fcntl.h>
+#include <ifaddrs.h>
+#include <limits.h>
+#include <linux/wireless.h>
+#include <locale.h>
+#include <netdb.h>
+#include <pwd.h>
 #include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <sys/statvfs.h>
+#include <sys/socket.h>
+#include <sys/types.h>
 #include <time.h>
 #include <unistd.h>
 #include <X11/Xlib.h>
 
-/* local libraries */
+/* local headers */
+#include "slstatus.h"
 #include "config.h"
 
-/* functions */
-void setstatus(char *str);
-char *smprintf(char *fmt, ...);
-char *get_battery();
-char *get_cpu_temperature();
-char *get_cpu_usage();
-char *get_datetime();
-char *get_ram_usage();
-char *get_volume();
-char *get_wifi_signal();
-
-/* global variables */
-static Display *dpy;
-
-/* set statusbar (WM_NAME) */
+/* set statusbar */
 void
-setstatus(char *str)
+setstatus(const char *str)
 {
-    XStoreName(dpy, DefaultRootWindow(dpy), str);
-    XSync(dpy, False);
+	/* set WM_NAME via X11 */
+	XStoreName(dpy, DefaultRootWindow(dpy), str);
+	XSync(dpy, False);
 }
 
 /* smprintf function */
 char *
-smprintf(char *fmt, ...)
+smprintf(const char *fmt, ...)
 {
-    va_list fmtargs;
-    char *ret = NULL;
-    va_start(fmtargs, fmt);
-    if (vasprintf(&ret, fmt, fmtargs) < 0)
-        return NULL;
-    va_end(fmtargs);
-
-    return ret;
+	va_list fmtargs;
+	char *ret = NULL;
+
+	va_start(fmtargs, fmt);
+	if (vasprintf(&ret, fmt, fmtargs) < 0) {
+		return NULL;
+	}
+	va_end(fmtargs);
+
+	return ret;
 }
 
 /* battery percentage */
 char *
-get_battery()
+battery_perc(const char *battery)
+{
+	int now, full, perc;
+	char batterynowfile[64] = "";
+	char batteryfullfile[64] = "";
+	FILE *fp;
+
+	/* generate battery nowfile path */
+	strcat(batterynowfile, batterypath);
+	strcat(batterynowfile, battery);
+	strcat(batterynowfile, "/");
+	strcat(batterynowfile, batterynow);
+
+	/* generate battery fullfile path */
+	strcat(batteryfullfile, batterypath);
+	strcat(batteryfullfile, battery);
+	strcat(batteryfullfile, "/");
+	strcat(batteryfullfile, batteryfull);
+
+	/* open battery now file */
+	if (!(fp = fopen(batterynowfile, "r"))) {
+		fprintf(stderr, "Error opening battery file.%s", batterynowfile);
+		return smprintf("n/a");
+	}
+
+	/* read value */
+	fscanf(fp, "%i", &now);
+
+	/* close battery now file */
+	fclose(fp);
+
+	/* open battery full file */
+	if (!(fp = fopen(batteryfullfile, "r"))) {
+		fprintf(stderr, "Error opening battery file.");
+		return smprintf("n/a");
+	}
+
+	/* read value */
+	fscanf(fp, "%i", &full);
+
+	/* close battery full file */
+	fclose(fp);
+
+	/* calculate percent */
+	perc = now / (full / 100);
+
+	/* return perc as string */
+	return smprintf("%d%%", perc);
+}
+
+/* cpu percentage */
+char *
+cpu_perc(const char *null)
 {
-    int now, full, perc;
-    FILE *fp;
+	int perc;
+	long double a[4], b[4];
+	FILE *fp;
+
+	/* open stat file */
+	if (!(fp = fopen("/proc/stat","r"))) {
+		fprintf(stderr, "Error opening stat file.");
+		return smprintf("n/a");
+	}
+
+	/* read values */
+	fscanf(fp, "%*s %Lf %Lf %Lf %Lf", &a[0], &a[1], &a[2], &a[3]);
 
-    /* open battery now file */
-    if (!(fp = fopen(batterynowfile, "r"))) {
-        fprintf(stderr, "Error opening battery file.");
-        exit(1);
-    }
+	/* close stat file */
+	fclose(fp);
 
-    /* read value */
-    fscanf(fp, "%i", &now);
+	/* wait a second (for avg values) */
+	sleep(1);
 
-    /* close battery now file */
-    fclose(fp);
+	/* open stat file */
+	if (!(fp = fopen("/proc/stat","r"))) {
+		fprintf(stderr, "Error opening stat file.");
+		return smprintf("n/a");
+	}
 
-    /* open battery full file */
-    if (!(fp = fopen(batteryfullfile, "r"))) {
-        fprintf(stderr, "Error opening battery file.");
-        exit(1);
-    }
+	/* read values */
+	fscanf(fp, "%*s %Lf %Lf %Lf %Lf", &b[0], &b[1], &b[2], &b[3]);
 
-    /* read value */
-    fscanf(fp, "%i", &full);
+	/* close stat file */
+	fclose(fp);
 
-    /* close battery full file */
-    fclose(fp);
+	/* calculate avg in this second */
+	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]));
 
-    /* calculate percent */
-    perc = now / (full / 100);
+	/* return perc as string */
+	return smprintf("%d%%", perc);
+}
 
-    /* return perc as string */
-    return smprintf("%d%%", perc);
+/* date and time */
+char *
+datetime(const char *timeformat)
+{
+	time_t tm;
+	size_t bufsize = 64;
+	char *buf = malloc(bufsize);
+	if (buf == NULL) {
+		fprintf(stderr, "Failed to get date/time");
+		return smprintf("n/a");
+	}
+
+	/* get time in format */
+	time(&tm);
+	setlocale(LC_TIME, "");
+	if (!strftime(buf, bufsize, timeformat, localtime(&tm))) {
+		setlocale(LC_TIME, "C");
+		free(buf);
+		fprintf(stderr, "Strftime failed.\n");
+		return smprintf("n/a");
+	}
+
+	setlocale(LC_TIME, "C");
+	/* return time */
+	char *ret = smprintf("%s", buf);
+	free(buf);
+	return ret;
 }
 
-/* cpu temperature */
+/* disk free */
 char *
-get_cpu_temperature()
+disk_free(const char *mountpoint)
 {
-    int temperature;
-    FILE *fp;
+	struct statvfs fs;
+
+	/* try to open mountpoint */
+	if (statvfs(mountpoint, &fs) < 0) {
+		fprintf(stderr, "Could not get filesystem info.\n");
+		return smprintf("n/a");
+	}
+
+	/* return free */
+	return smprintf("%f", (float)fs.f_bsize * (float)fs.f_bfree / 1024 / 1024 / 1024);
+}
 
-    /* open temperature file */
-    if (!(fp = fopen(tempfile, "r"))) {
-        fprintf(stderr, "Could not open temperature file.\n");
-        exit(1);
-    }
+/* disk usage percentage */
+char *
+disk_perc(const char *mountpoint)
+{
+	int perc = 0;
+	struct statvfs fs;
 
-    /* extract temperature */
-    fscanf(fp, "%d", &temperature);
+	/* try to open mountpoint */
+	if (statvfs(mountpoint, &fs) < 0) {
+		fprintf(stderr, "Could not get filesystem info.\n");
+		return smprintf("n/a");
+	}
 
-    /* close temperature file */
-    fclose(fp);
+	/* calculate percent */
+	perc = 100 * (1.0f - ((float)fs.f_bfree / (float)fs.f_blocks));
 
-    /* return temperature in degrees */
-    return smprintf("%d°C", temperature / 1000);
+	/* return perc */
+	return smprintf("%d%%", perc);
 }
 
-/* cpu percentage */
+/* disk total */
 char *
-get_cpu_usage()
+disk_total(const char *mountpoint)
 {
-    int perc;
-    long double a[4], b[4];
-    FILE *fp;
+	struct statvfs fs;
 
-    /* open stat file */
-    if (!(fp = fopen("/proc/stat","r"))) {
-        fprintf(stderr, "Error opening stat file.");
-        exit(1);
-    }
+	/* try to open mountpoint */
+	if (statvfs(mountpoint, &fs) < 0) {
+		fprintf(stderr, "Could not get filesystem info.\n");
+		return smprintf("n/a");
+	}
 
-    /* read values */
-    fscanf(fp, "%*s %Lf %Lf %Lf %Lf", &a[0], &a[1], &a[2], &a[3]);
+	/* return total */
+	return smprintf("%f", (float)fs.f_bsize * (float)fs.f_blocks / 1024 / 1024 / 1024);
+}
 
-    /* close stat file */
-    fclose(fp);
+/* disk used */
+char *
+disk_used(const char *mountpoint)
+{
+	struct statvfs fs;
 
-    /* wait a second (for avg values) */
-    sleep(1);
+	/* try to open mountpoint */
+	if (statvfs(mountpoint, &fs) < 0) {
+		fprintf(stderr, "Could not get filesystem info.\n");
+		return smprintf("n/a");
+	}
 
-    /* open stat file */
-    if (!(fp = fopen("/proc/stat","r"))) {
-        fprintf(stderr, "Error opening stat file.");
-        exit(1);
-    }
+	/* return used */
+	return smprintf("%f", (float)fs.f_bsize * ((float)fs.f_blocks - (float)fs.f_bfree) / 1024 / 1024 / 1024);
+}
 
-    /* read values */
-    fscanf(fp, "%*s %Lf %Lf %Lf %Lf", &b[0], &b[1], &b[2], &b[3]);
+/* entropy available */
+char *
+entropy(const char *null)
+{
+	int entropy = 0;
+	FILE *fp;
+
+	/* open entropy file */
+	if (!(fp = fopen("/proc/sys/kernel/random/entropy_avail", "r"))) {
+		fprintf(stderr, "Could not open entropy file.\n");
+		return smprintf("n/a");
+	}
 
-    /* close stat file */
-    fclose(fp);
+	/* extract entropy */
+	fscanf(fp, "%d", &entropy);
 
-    /* calculate avg in this second */
-    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]));
+	/* close entropy file */
+	fclose(fp);
 
-    /* return perc as string */
-    return smprintf("%d%%", perc);
+	/* return entropy */
+	return smprintf("%d", entropy);
 }
 
-/* date and time */
+/* gid */
+char *
+gid(const char *null)
+{
+	gid_t gid;
+
+	if ((gid = getgid()) < 0) {
+		fprintf(stderr, "Could no get gid.");
+		return smprintf("n/a");
+	} else {
+		return smprintf("%d", gid);
+	}
+
+	return smprintf("n/a");
+}
+
+/* hostname */
 char *
-get_datetime()
+hostname(const char *null)
 {
-    time_t tm;
-    size_t bufsize = 64;
-    char *buf = malloc(bufsize);
-
-    /* get time in format */
-    time(&tm);
-    if(!strftime(buf, bufsize, timeformat, localtime(&tm))) {
-      fprintf(stderr, "Strftime failed.\n");
-        exit(1);
-    }
-
-    /* return time */
-    return smprintf("%s", buf);
+	char hostname[HOST_NAME_MAX];
+	FILE *fp;
+
+	/* open hostname file */
+	if (!(fp = fopen("/proc/sys/kernel/hostname", "r"))) {
+		fprintf(stderr, "Could not open hostname file.\n");
+		return smprintf("n/a");
+	}
+
+	/* extract hostname */
+	fscanf(fp, "%s\n", hostname);
+
+	/* close hostname file */
+	fclose(fp);
+
+	/* return entropy */
+	return smprintf("%s", hostname);
+}
+
+/* ip address */
+char *
+ip(const char *interface)
+{
+	struct ifaddrs *ifaddr, *ifa;
+	int s;
+	char host[NI_MAXHOST];
+
+	/* check if getting ip address works */
+	if (getifaddrs(&ifaddr) == -1) {
+		fprintf(stderr, "Error getting IP address.");
+		return smprintf("n/a");
+	}
+
+	/* get the ip address */
+	for (ifa = ifaddr; ifa != NULL; ifa = ifa->ifa_next) {
+		if (ifa->ifa_addr == NULL) {
+			continue;
+		}
+
+		s = getnameinfo(ifa->ifa_addr, sizeof(struct sockaddr_in), host, NI_MAXHOST, NULL, 0, NI_NUMERICHOST);
+
+		if ((strcmp(ifa->ifa_name, interface) == 0) && (ifa->ifa_addr->sa_family == AF_INET)) {
+			if (s != 0) {
+				fprintf(stderr, "Error getting IP address.");
+				return smprintf("n/a");
+			}
+			return smprintf("%s", host);
+		}
+	}
+
+	/* free the address */
+	freeifaddrs(ifaddr);
+
+	/* return n/a if nothing works */
+	return smprintf("n/a");
+}
+
+/* ram free */
+char *
+ram_free(const char *null)
+{
+	long free;
+	FILE *fp;
+
+	/* open meminfo file */
+	if (!(fp = fopen("/proc/meminfo", "r"))) {
+		fprintf(stderr, "Error opening meminfo file.");
+		return smprintf("n/a");
+	}
+
+	/* read the values */
+	fscanf(fp, "MemFree: %ld kB\n", &free);
+
+	/* close meminfo file */
+	fclose(fp);
+
+	/* return free ram as string */
+	return smprintf("%f", (float)free / 1024 / 1024);
 }
 
 /* ram percentage */
 char *
-get_ram_usage()
+ram_perc(const char *null)
+{
+	int perc;
+	long total, free, buffers, cached;
+	FILE *fp;
+
+	/* open meminfo file */
+	if (!(fp = fopen("/proc/meminfo", "r"))) {
+		fprintf(stderr, "Error opening meminfo file.");
+		return smprintf("n/a");
+	}
+
+	/* read the values */
+	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);
+
+	/* close meminfo file */
+	fclose(fp);
+
+	/* calculate percentage */
+	perc = 100 * ((total - free) - (buffers + cached)) / total;
+
+	/* return perc as string */
+	return smprintf("%d%%", perc);
+}
+
+/* ram total */
+char *
+ram_total(const char *null)
+{
+	long total;
+	FILE *fp;
+
+	/* open meminfo file */
+	if (!(fp = fopen("/proc/meminfo", "r"))) {
+		fprintf(stderr, "Error opening meminfo file.");
+		return smprintf("n/a");
+	}
+
+	/* read the values */
+	fscanf(fp, "MemTotal: %ld kB\n", &total);
+
+	/* close meminfo file */
+	fclose(fp);
+
+	/* return total ram as string */
+	return smprintf("%f", (float)total / 1024 / 1024);
+}
+
+/* ram used */
+char *
+ram_used(const char *null)
+{
+	long free, total, buffers, cached, used;
+	FILE *fp;
+
+	/* open meminfo file */
+	if (!(fp = fopen("/proc/meminfo", "r"))) {
+		fprintf(stderr, "Error opening meminfo file.");
+		return smprintf("n/a");
+	}
+
+	/* read the values */
+	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);
+
+	/* close meminfo file */
+	fclose(fp);
+
+	/* calculate used */
+	used = total - free - buffers - cached;
+
+	/* return used ram as string */
+	return smprintf("%f", (float)used / 1024 / 1024);
+}
+
+/* custom shell command */
+char *
+run_command(const char* command)
 {
-    int perc;
-    long total, free, buffers, cached;
-    FILE *fp;
-
-    /* open meminfo file */
-    if (!(fp = fopen("/proc/meminfo", "r"))) {
-        fprintf(stderr, "Error opening meminfo file.");
-        exit(1);
-    }
-
-    /* read the values */
-    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);
-
-    /* close meminfo file */
-    fclose(fp);
-
-    /* calculate percentage */
-    perc = 100 * ((total - free) - (buffers + cached)) / total;
-
-    /* return perc as string */
-    return smprintf("%d%%", perc);
+	int good;
+	FILE *fp;
+	char buffer[64];
+
+	/* try to open the command output */
+	if (!(fp = popen(command, "r"))) {
+		fprintf(stderr, "Could not get command output for: %s.\n", command);
+		return smprintf("n/a");
+	}
+
+	/* get command output text, save it to buffer */
+	fgets(buffer, sizeof(buffer) - 1, fp);
+
+	/* close it again */
+	pclose(fp);
+
+	/* add nullchar at the end */
+	for (int i = 0 ; i != sizeof(buffer); i++) {
+		if (buffer[i] == '\0') {
+			good = 1;
+			break;
+		}
+	}
+	if (good) {
+		buffer[strlen(buffer) - 1] = '\0';
+	}
+
+	/* return the output */
+	return smprintf("%s", buffer);
 }
 
+/* temperature */
+char *
+temp(const char *file)
+{
+	int temperature;
+	FILE *fp;
+
+	/* open temperature file */
+	if (!(fp = fopen(file, "r"))) {
+		fprintf(stderr, "Could not open temperature file.\n");
+		return smprintf("n/a");
+	}
+
+	/* extract temperature */
+	fscanf(fp, "%d", &temperature);
+
+	/* close temperature file */
+	fclose(fp);
+
+	/* return temperature in degrees */
+	return smprintf("%d°C", temperature / 1000);
+}
+
+/* username */
+char *
+username(const char *null)
+{
+	register struct passwd *pw;
+	register uid_t uid;
+
+	/* get the values */
+	uid = geteuid();
+	pw = getpwuid(uid);
+
+	/* if it worked, return */
+	if (pw) {
+		return smprintf("%s", pw->pw_name);
+	} else {
+		fprintf(stderr, "Could not get username.\n");
+		return smprintf("n/a");
+	}
+
+	return smprintf("n/a");
+}
+
+/* uid */
+char *
+uid(const char *null)
+{
+	register uid_t uid;
+
+	/* get the values */
+	uid = geteuid();
+
+	/* if it worked, return */
+	if (uid) {
+		return smprintf("%d", uid);
+	} else {
+		fprintf(stderr, "Could not get uid.\n");
+		return smprintf("n/a");
+	}
+
+	return smprintf("n/a");
+}
+
+
 /* alsa volume percentage */
 char *
-get_volume()
+vol_perc(const char *soundcard)
 {
-    int mute = 0;
-    long vol = 0, max = 0, min = 0;
-
-    /* get volume from alsa */
-    snd_mixer_t *handle;
-    snd_mixer_elem_t *pcm_mixer, *mas_mixer;
-    snd_mixer_selem_id_t *vol_info, *mute_info;
-    snd_mixer_open(&handle, 0);
-    snd_mixer_attach(handle, soundcard);
-    snd_mixer_selem_register(handle, NULL, NULL);
-    snd_mixer_load(handle);
-    snd_mixer_selem_id_malloc(&vol_info);
-    snd_mixer_selem_id_malloc(&mute_info);
-    snd_mixer_selem_id_set_name(vol_info, channel);
-    snd_mixer_selem_id_set_name(mute_info, channel);
-    pcm_mixer = snd_mixer_find_selem(handle, vol_info);
-    mas_mixer = snd_mixer_find_selem(handle, mute_info);
-    snd_mixer_selem_get_playback_volume_range((snd_mixer_elem_t *)pcm_mixer, &min, &max);
-    snd_mixer_selem_get_playback_volume((snd_mixer_elem_t *)pcm_mixer, SND_MIXER_SCHN_MONO, &vol);
-    snd_mixer_selem_get_playback_switch(mas_mixer, SND_MIXER_SCHN_MONO, &mute);
-    if (vol_info)
-        snd_mixer_selem_id_free(vol_info);
-    if (mute_info)
-        snd_mixer_selem_id_free(mute_info);
-    if (handle)
-        snd_mixer_close(handle);
-
-    /* return the string (mute) */
-    if (!mute)
-        return smprintf("mute");
-    else
-        return smprintf("%d%%", (vol * 100) / max);
+	int mute = 0;
+	long vol = 0, max = 0, min = 0;
+	snd_mixer_t *handle;
+	snd_mixer_elem_t *pcm_mixer, *mas_mixer;
+	snd_mixer_selem_id_t *vol_info, *mute_info;
+
+	/* open everything */
+	snd_mixer_open(&handle, 0);
+	snd_mixer_attach(handle, soundcard);
+	snd_mixer_selem_register(handle, NULL, NULL);
+	snd_mixer_load(handle);
+
+	/* prepare everything */
+	snd_mixer_selem_id_malloc(&vol_info);
+	snd_mixer_selem_id_malloc(&mute_info);
+	/* check */
+	if (vol_info == NULL || mute_info == NULL) {
+		fprintf(stderr, "Could not get alsa volume");
+		return smprintf("n/a");
+	}
+	snd_mixer_selem_id_set_name(vol_info, channel);
+	snd_mixer_selem_id_set_name(mute_info, channel);
+	pcm_mixer = snd_mixer_find_selem(handle, vol_info);
+	mas_mixer = snd_mixer_find_selem(handle, mute_info);
+
+	/* get the info */
+	snd_mixer_selem_get_playback_volume_range((snd_mixer_elem_t *)pcm_mixer, &min, &max);
+	snd_mixer_selem_get_playback_volume((snd_mixer_elem_t *)pcm_mixer, SND_MIXER_SCHN_MONO, &vol);
+	snd_mixer_selem_get_playback_switch(mas_mixer, SND_MIXER_SCHN_MONO, &mute);
+
+	/* clean up */
+	if (vol_info) {
+		snd_mixer_selem_id_free(vol_info);
+	}
+	if (mute_info) {
+		snd_mixer_selem_id_free(mute_info);
+	}
+	if (handle) {
+		snd_mixer_close(handle);
+	}
+
+	/* return the string (mute) */
+	if (!mute) {
+		return smprintf("mute");
+	} else {
+		return smprintf("%d%%", (vol * 100) / max);
+	}
 }
 
 /* wifi percentage */
 char *
-get_wifi_signal()
+wifi_perc(const char *wificard)
+{
+	int bufsize = 255;
+	int strength;
+	char buf[bufsize];
+	char *datastart;
+	char path[64];
+	char status[5];
+	char needle[sizeof wificard + 1];
+	FILE *fp;
+
+	/* generate the path name */
+	memset(path, 0, sizeof path);
+	strcat(path, "/sys/class/net/");
+	strcat(path, wificard);
+	strcat(path, "/operstate");
+
+	/* open wifi file */
+	if(!(fp = fopen(path, "r"))) {
+		fprintf(stderr, "Error opening wifi operstate file.");
+		return smprintf("n/a");
+	}
+
+	/* read the status */
+	fgets(status, 5, fp);
+
+	/* close wifi file */
+	fclose(fp);
+
+	/* check if interface down */
+	if(strcmp(status, "up\n") != 0) {
+		return smprintf("n/a");
+	}
+
+	/* open wifi file */
+	if (!(fp = fopen("/proc/net/wireless", "r"))) {
+		fprintf(stderr, "Error opening wireless file.");
+		return smprintf("n/a");
+	}
+
+	/* extract the signal strength */
+	strcpy(needle, wificard);
+	strcat(needle, ":");
+	fgets(buf, bufsize, fp);
+	fgets(buf, bufsize, fp);
+	fgets(buf, bufsize, fp);
+	if ((datastart = strstr(buf, needle)) != NULL) {
+		datastart = strstr(buf, ":");
+		sscanf(datastart + 1, " %*d   %d  %*d  %*d		  %*d	   %*d		%*d		 %*d	  %*d		 %*d", &strength);
+	}
+
+	/* close wifi file */
+	fclose(fp);
+
+	/* return strength in percent */
+	return smprintf("%d%%", strength);
+}
+
+/* wifi essid */
+char *
+wifi_essid(const char *wificard)
 {
-    int bufsize = 255;
-    int strength;
-    char buf[bufsize];
-    char *datastart;
-    char path_start[16] = "/sys/class/net/";
-    char path_end[11] = "/operstate";
-    char path[32];
-    char status[5];
-    char needle[sizeof wificard + 1];
-    FILE *fp;
-
-    /* generate the path name */
-    memset(path, 0, sizeof path);
-    strcat(path, path_start);
-    strcat(path, wificard);
-    strcat(path, path_end);
-
-    /* open wifi file */
-    if(!(fp = fopen(path, "r"))) {
-        fprintf(stderr, "Error opening wifi operstate file.");
-        exit(1);
-    }
-
-    /* read the status */
-    fgets(status, 5, fp);
-
-    /* close wifi file */
-    fclose(fp);
-
-    /* check if interface down */
-    if(strcmp(status, "up\n") != 0){
-        return "n/a";
-    }
-
-    /* open wifi file */
-    if (!(fp = fopen("/proc/net/wireless", "r"))) {
-        fprintf(stderr, "Error opening wireless file.");
-        exit(1);
-    }
-
-    /* extract the signal strength */
-    strcpy(needle, wificard);
-    strcat(needle, ":");
-    fgets(buf, bufsize, fp);
-    fgets(buf, bufsize, fp);
-    fgets(buf, bufsize, fp);
-    if ((datastart = strstr(buf, needle)) != NULL) {
-        datastart = strstr(buf, ":");
-        sscanf(datastart + 1, " %*d   %d  %*d  %*d        %*d      %*d      %*d      %*d      %*d        %*d", &strength);
-    }
-
-    /* close wifi file */
-    fclose(fp);
-
-    /* return strength in percent */
-    return smprintf("%d%%", strength);
+	char id[IW_ESSID_MAX_SIZE+1];
+	int sockfd;
+	struct iwreq wreq;
+
+	/* prepare */
+	memset(&wreq, 0, sizeof(struct iwreq));
+	wreq.u.essid.length = IW_ESSID_MAX_SIZE+1;
+
+	/* set the interface */
+	sprintf(wreq.ifr_name, wificard);
+
+	/* check */
+	if((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) == -1) {
+		fprintf(stderr, "Cannot open socket for interface: %s\n", wificard);
+		return smprintf("n/a");
+	}
+	wreq.u.essid.pointer = id;
+	if (ioctl(sockfd,SIOCGIWESSID, &wreq) == -1) {
+		fprintf(stderr, "Get ESSID ioctl failed for interface %s\n", wificard);
+		return smprintf("n/a");
+	}
+
+	/* return the essid */
+	if (strcmp((char *)wreq.u.essid.pointer, "") == 0) {
+		return smprintf("n/a");
+	} else {
+		return smprintf("%s", (char *)wreq.u.essid.pointer);
+	}
 }
 
 /* main function */
 int
-main()
+main(void)
 {
-    char status[1024];
-    char *battery = NULL;
-    char *cpu_temperature = NULL;
-    char *cpu_usage = NULL;
-    char *datetime = NULL;
-    char *ram_usage = NULL;
-    char *volume = NULL;
-    char *wifi_signal = NULL;
-
-    /* open display */
-    if (!(dpy = XOpenDisplay(0x0))) {
-        fprintf(stderr, "Cannot open display!\n");
-        exit(1);
-    }
-
-    /* return status every second */
-    for (;;) {
-        /* assign the values */
-        battery = get_battery();
-        cpu_temperature = get_cpu_temperature();
-        cpu_usage = get_cpu_usage();
-        datetime = get_datetime();
-        ram_usage = get_ram_usage();
-        volume = get_volume();
-        wifi_signal = get_wifi_signal();
-
-        /* return the status */
-        sprintf(status, FORMATSTRING, ARGUMENTS);
-        setstatus(status);
-
-        /* free the values */
-        free(battery);
-        free(cpu_temperature);
-        free(cpu_usage);
-        free(datetime);
-        free(ram_usage);
-        free(volume);
-        free(wifi_signal);
-        sleep(update_interval);
-    }
-
-    /* close display */
-    XCloseDisplay(dpy);
-
-    /* exit successfully */
-    return 0;
+	char status_string[1024];
+	struct arg argument;
+
+	/* try to open display */
+	if (!(dpy = XOpenDisplay(0x0))) {
+		fprintf(stderr, "Cannot open display!\n");
+		exit(1);
+	}
+
+	/* return status every interval */
+	for (;;) {
+		/* clear the string */
+		memset(status_string, 0, sizeof(status_string));
+
+		/* generate status_string */
+		for (size_t i = 0; i < sizeof(args) / sizeof(args[0]); ++i) {
+			argument = args[i];
+			char *res = argument.func(argument.args);
+			char *element = smprintf(argument.format, res);
+			if (element == NULL) {
+				element = smprintf("n/a");
+				fprintf(stderr, "Failed to format output.");
+			}
+			strcat(status_string, element);
+			free(res);
+			free(element);
+		}
+
+		/* return the statusbar */
+		setstatus(status_string);
+
+		/* wait, "update_interval - 1" because of get_cpu_usage() which uses 1 second */
+		sleep(update_interval -1);
+	}
+
+	/* close display */
+	XCloseDisplay(dpy);
+
+	/* exit successfully */
+	return 0;
 }