added everything

LICENSE

@@ -0,0 +1,40 @@
+ISC License
+
+Copyright 2016-2020 Aaron Marcher <me@drkhsh.at>
+
+Copyright 2016 Roy Freytag <rfreytag@hs-mittweida.de>
+Copyright 2016 Vincent Loupmon <vincentloupmon@gmail.com>
+Copyright 2016 Daniel Walter <d.walter@0x90.at>
+Copyright 2016-2018 Ali H. Fardan <raiz@firemail.cc>
+Copyright 2016 Jody Leonard <me@jodyleonard.com>
+Copyright 2016-2018 Quentin Rameau <quinq@fifth.space>
+Copyright 2016 Mike Coddington <mike@coddington.us>
+Copyright 2016-2018 parazyd <parazyd@dyne.org>
+Copyright 2017 Tobias Stoeckmann <tobias@stoeckmann.org>
+Copyright 2017-2018 Laslo Hunhold <dev@frign.de>
+Copyright 2018 Darron Anderson <darronanderson@protonmail.com>
+Copyright 2018 Josuah Demangeon <mail@josuah.net>
+Copyright 2018 Tobias Tschinkowitz <tobias@he4d.net>
+Copyright 2018 David Demelier <markand@malikania.fr>
+Copyright 2018-2019 Michael Buch <michaelbuch12@gmail.com>
+Copyright 2018 Ian Remmler <ian@remmler.org>
+Copyright 2016-2019 Joerg Jung <jung@openbsd.org>
+Copyright 2019 Ryan Kes <alrayyes@gmail.com>
+Copyright 2019 Cem Keylan <cem@ckyln.com>
+Copyright 2019 dsp <dsp@2f30.org>
+Copyright 2019-2020 Ingo Feinerer <feinerer@logic.at>
+Copyright 2020 Alexandre Ratchov <alex@caoua.org>
+Copyright 2020 Mart Lubbers <mart@martlubbers.net>
+Copyright 2020 Daniel Moch <daniel@danielmoch.com>
+
+Permission to use, copy, modify, and/or distribute this software for any
+purpose with or without fee is hereby granted, provided that the above
+copyright notice and this permission notice appear in all copies.
+
+THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

Makefile

@@ -0,0 +1,68 @@
+# See LICENSE file for copyright and license details
+# slstatus - suckless status monitor
+.POSIX:
+
+include config.mk
+
+REQ = util
+COM =\
+	components/battery\
+	components/cpu\
+	components/datetime\
+	components/disk\
+	components/entropy\
+	components/hostname\
+	components/ip\
+	components/kernel_release\
+	components/keyboard_indicators\
+	components/keymap\
+	components/load_avg\
+	components/netspeeds\
+	components/num_files\
+	components/ram\
+	components/run_command\
+	components/separator\
+	components/swap\
+	components/temperature\
+	components/uptime\
+	components/user\
+	components/volume\
+	components/wifi
+
+all: slstatus
+
+$(COM:=.o): config.mk $(REQ:=.h)
+slstatus.o: slstatus.c slstatus.h arg.h config.h config.mk $(REQ:=.h)
+
+.c.o:
+	$(CC) -o $@ -c $(CPPFLAGS) $(CFLAGS) $<
+
+config.h:
+	cp config.def.h $@
+
+slstatus: slstatus.o $(COM:=.o) $(REQ:=.o)
+	$(CC) -o $@ $(LDFLAGS) $(COM:=.o) $(REQ:=.o) slstatus.o $(LDLIBS)
+
+clean:
+	rm -f slstatus slstatus.o $(COM:=.o) $(REQ:=.o)
+
+dist:
+	rm -rf "slstatus-$(VERSION)"
+	mkdir -p "slstatus-$(VERSION)/components"
+	cp -R LICENSE Makefile README config.mk config.def.h \
+	      arg.h slstatus.c $(COM:=.c) $(REQ:=.c) $(REQ:=.h) \
+	      slstatus.1 "slstatus-$(VERSION)"
+	tar -cf - "slstatus-$(VERSION)" | gzip -c > "slstatus-$(VERSION).tar.gz"
+	rm -rf "slstatus-$(VERSION)"
+
+install: all
+	mkdir -p "$(DESTDIR)$(PREFIX)/bin"
+	cp -f slstatus "$(DESTDIR)$(PREFIX)/bin"
+	chmod 755 "$(DESTDIR)$(PREFIX)/bin/slstatus"
+	mkdir -p "$(DESTDIR)$(MANPREFIX)/man1"
+	cp -f slstatus.1 "$(DESTDIR)$(MANPREFIX)/man1"
+	chmod 644 "$(DESTDIR)$(MANPREFIX)/man1/slstatus.1"
+
+uninstall:
+	rm -f "$(DESTDIR)$(PREFIX)/bin/slstatus"
+	rm -f "$(DESTDIR)$(MANPREFIX)/man1/slstatus.1"

README

@@ -0,0 +1,65 @@
+slstatus - suckless status
+==========================
+slstatus is a suckless status monitor for window managers that use WM_NAME
+(e.g. dwm) or stdin to fill the status bar.
+
+
+Features
+--------
+- Battery percentage/state/time left
+- CPU usage
+- CPU frequency
+- Custom shell commands
+- Date and time
+- Disk status (free storage, percentage, total storage and used storage)
+- Available entropy
+- Username/GID/UID
+- Hostname
+- IP address (IPv4 and IPv6)
+- Kernel version
+- Keyboard indicators
+- Keymap
+- Load average
+- Network speeds (RX and TX)
+- Number of files in a directory (hint: Maildir)
+- Memory status (free memory, percentage, total memory and used memory)
+- Swap status (free swap, percentage, total swap and used swap)
+- Temperature
+- Uptime
+- Volume percentage
+- WiFi signal percentage and ESSID
+
+
+Requirements
+------------
+Currently slstatus works on FreeBSD, Linux and OpenBSD.
+In order to build slstatus you need the Xlib header files.
+
+
+Installation
+------------
+Edit config.mk to match your local setup (slstatus is installed into the
+/usr/local namespace by default).
+
+Afterwards enter the following command to build and install slstatus (if
+necessary as root):
+
+    make clean install
+
+
+Running slstatus
+----------------
+See the man page for details.
+
+
+Configuration
+-------------
+slstatus can be customized by creating a custom config.h and (re)compiling the
+source code. This keeps it fast, secure and simple.
+
+
+Upcoming
+--------
+
+A release (v1.0) will come soon... ;)
+After a long phase of inactivity, development has been continued!

arg.h

@@ -0,0 +1,33 @@
+/* See LICENSE file for copyright and license details. */
+#ifndef ARG_H
+#define ARG_H
+
+extern char *argv0;
+
+/* int main(int argc, char *argv[]) */
+#define ARGBEGIN for (argv0 = *argv, *argv ? (argc--, argv++) : ((void *)0);      \
+                      *argv && (*argv)[0] == '-' && (*argv)[1]; argc--, argv++) { \
+                 	int i_, argused_;                                         \
+                 	if ((*argv)[1] == '-' && !(*argv)[2]) {                   \
+                 		argc--, argv++;                                   \
+                 		break;                                            \
+                 	}                                                         \
+                 	for (i_ = 1, argused_ = 0; (*argv)[i_]; i_++) {           \
+                 		switch((*argv)[i_])
+#define ARGEND   		if (argused_) {                                   \
+                 			if ((*argv)[i_ + 1]) {                    \
+                 				break;                            \
+                 			} else {                                  \
+                 				argc--, argv++;                   \
+                 				break;                            \
+                 			}                                         \
+                 		}                                                 \
+                 	}                                                         \
+                 }
+#define ARGC()   ((*argv)[i_])
+#define ARGF_(x) (((*argv)[i_ + 1]) ? (argused_ = 1, &((*argv)[i_ + 1])) :        \
+                  (*(argv + 1))     ? (argused_ = 1, *(argv + 1))        : (x))
+#define EARGF(x) ARGF_(((x), exit(1), (char *)0))
+#define ARGF()   ARGF_((char *)0)
+
+#endif

components/battery.c

@@ -0,0 +1,252 @@
+/* See LICENSE file for copyright and license details. */
+#include <stdio.h>
+#include <string.h>
+
+#include "../util.h"
+
+#if defined(__linux__)
+	#include <limits.h>
+	#include <stdint.h>
+	#include <unistd.h>
+
+	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;
+		}
+
+		return NULL;
+	}
+
+	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", "-" },
+			{ "Full",        "o" },
+		};
+		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)
+	{
+		uintmax_t 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, "/sys/class/power_supply/%s/charge_now",
+		          "/sys/class/power_supply/%s/energy_now", path,
+		          sizeof(path)) ||
+		    pscanf(path, "%ju", &charge_now) < 0) {
+			return NULL;
+		}
+
+		if (!strcmp(state, "Discharging")) {
+			if (!pick(bat, "/sys/class/power_supply/%s/current_now",
+			          "/sys/class/power_supply/%s/power_now", path,
+			          sizeof(path)) ||
+			    pscanf(path, "%ju", &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("%juh %jum", 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;
+	}
+
+	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;
+		}
+
+		return NULL;
+	}
+
+	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;
+	}
+#elif defined(__FreeBSD__)
+	#include <sys/sysctl.h>
+
+	const char *
+	battery_perc(const char *unused)
+	{
+		int cap;
+		size_t len;
+
+		len = sizeof(cap);
+		if (sysctlbyname("hw.acpi.battery.life", &cap, &len, NULL, 0) == -1
+				|| !len)
+			return NULL;
+
+		return bprintf("%d", cap);
+	}
+
+	const char *
+	battery_state(const char *unused)
+	{
+		int state;
+		size_t len;
+
+		len = sizeof(state);
+		if (sysctlbyname("hw.acpi.battery.state", &state, &len, NULL, 0) == -1
+				|| !len)
+			return NULL;
+
+		switch(state) {
+			case 0:
+			case 2:
+				return "+";
+			case 1:
+				return "-";
+			default:
+				return "?";
+		}
+	}
+
+	const char *
+	battery_remaining(const char *unused)
+	{
+		int rem;
+		size_t len;
+
+		len = sizeof(rem);
+		if (sysctlbyname("hw.acpi.battery.time", &rem, &len, NULL, 0) == -1
+				|| !len
+				|| rem == -1)
+			return NULL;
+
+		return bprintf("%uh %02um", rem / 60, rem % 60);
+	}
+#endif

components/cpu.c

@@ -0,0 +1,164 @@
+/* See LICENSE file for copyright and license details. */
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "../util.h"
+
+#if defined(__linux__)
+	const char *
+	cpu_freq(void)
+	{
+		uintmax_t freq;
+
+		/* in kHz */
+		if (pscanf("/sys/devices/system/cpu/cpu0/cpufreq/"
+		           "scaling_cur_freq", "%ju", &freq) != 1) {
+			return NULL;
+		}
+
+		return fmt_human(freq * 1000, 1000);
+	}
+
+	const char *
+	cpu_perc(void)
+	{
+		static long double a[7];
+		long double b[7], sum;
+
+		memcpy(b, a, sizeof(b));
+		/* cpu user nice system idle iowait irq softirq */
+		if (pscanf("/proc/stat", "%*s %Lf %Lf %Lf %Lf %Lf %Lf %Lf",
+		           &a[0], &a[1], &a[2], &a[3], &a[4], &a[5], &a[6])
+		    != 7) {
+			return NULL;
+		}
+		if (b[0] == 0) {
+			return NULL;
+		}
+
+		sum = (b[0] + b[1] + b[2] + b[3] + b[4] + b[5] + b[6]) -
+		      (a[0] + a[1] + a[2] + a[3] + a[4] + a[5] + a[6]);
+
+		if (sum == 0) {
+			return NULL;
+		}
+
+		return bprintf("%d", (int)(100 *
+		               ((b[0] + b[1] + b[2] + b[5] + b[6]) -
+		                (a[0] + a[1] + a[2] + a[5] + a[6])) / sum));
+	}
+#elif defined(__OpenBSD__)
+	#include <sys/param.h>
+	#include <sys/sched.h>
+	#include <sys/sysctl.h>
+
+	const char *
+	cpu_freq(void)
+	{
+		int freq, mib[2];
+		size_t size;
+
+		mib[0] = CTL_HW;
+		mib[1] = HW_CPUSPEED;
+
+		size = sizeof(freq);
+
+		/* in MHz */
+		if (sysctl(mib, 2, &freq, &size, NULL, 0) < 0) {
+			warn("sysctl 'HW_CPUSPEED':");
+			return NULL;
+		}
+
+		return fmt_human(freq * 1E6, 1000);
+	}
+
+	const char *
+	cpu_perc(void)
+	{
+		int mib[2];
+		static uintmax_t a[CPUSTATES];
+		uintmax_t b[CPUSTATES], sum;
+		size_t size;
+
+		mib[0] = CTL_KERN;
+		mib[1] = KERN_CPTIME;
+
+		size = sizeof(a);
+
+		memcpy(b, a, sizeof(b));
+		if (sysctl(mib, 2, &a, &size, NULL, 0) < 0) {
+			warn("sysctl 'KERN_CPTIME':");
+			return NULL;
+		}
+		if (b[0] == 0) {
+			return NULL;
+		}
+
+		sum = (a[CP_USER] + a[CP_NICE] + a[CP_SYS] + a[CP_INTR] + a[CP_IDLE]) -
+		      (b[CP_USER] + b[CP_NICE] + b[CP_SYS] + b[CP_INTR] + b[CP_IDLE]);
+
+		if (sum == 0) {
+			return NULL;
+		}
+
+		return bprintf("%d", 100 *
+		               ((a[CP_USER] + a[CP_NICE] + a[CP_SYS] +
+		                 a[CP_INTR]) -
+		                (b[CP_USER] + b[CP_NICE] + b[CP_SYS] +
+		                 b[CP_INTR])) / sum);
+	}
+#elif defined(__FreeBSD__)
+	#include <sys/param.h>
+	#include <sys/sysctl.h>
+	#include <devstat.h>
+
+	const char *
+	cpu_freq(void)
+	{
+		int freq;
+		size_t size;
+
+		size = sizeof(freq);
+		/* in MHz */
+		if (sysctlbyname("hw.clockrate", &freq, &size, NULL, 0) == -1
+				|| !size) {
+			warn("sysctlbyname 'hw.clockrate':");
+			return NULL;
+		}
+
+		return fmt_human(freq * 1E6, 1000);
+	}
+
+	const char *
+	cpu_perc(void)
+	{
+		size_t size;
+		static long a[CPUSTATES];
+		long b[CPUSTATES], sum;
+
+		size = sizeof(a);
+		memcpy(b, a, sizeof(b));
+		if (sysctlbyname("kern.cp_time", &a, &size, NULL, 0) == -1
+				|| !size) {
+			warn("sysctlbyname 'kern.cp_time':");
+			return NULL;
+		}
+		if (b[0] == 0) {
+			return NULL;
+		}
+
+		sum = (a[CP_USER] + a[CP_NICE] + a[CP_SYS] + a[CP_INTR] + a[CP_IDLE]) -
+		      (b[CP_USER] + b[CP_NICE] + b[CP_SYS] + b[CP_INTR] + b[CP_IDLE]);
+
+		if (sum == 0) {
+			return NULL;
+		}
+
+		return bprintf("%d", 100 *
+		               ((a[CP_USER] + a[CP_NICE] + a[CP_SYS] +
+		                 a[CP_INTR]) -
+		                (b[CP_USER] + b[CP_NICE] + b[CP_SYS] +
+		                 b[CP_INTR])) / sum);
+	}
+#endif

components/datetime.c

@@ -0,0 +1,19 @@
+/* See LICENSE file for copyright and license details. */
+#include <stdio.h>
+#include <time.h>
+
+#include "../util.h"
+
+const char *
+datetime(const char *fmt)
+{
+	time_t t;
+
+	t = time(NULL);
+	if (!strftime(buf, sizeof(buf), fmt, localtime(&t))) {
+		warn("strftime: Result string exceeds buffer size");
+		return NULL;
+	}
+
+	return buf;
+}

components/disk.c

@@ -0,0 +1,58 @@
+/* See LICENSE file for copyright and license details. */
+#include <stdio.h>
+#include <sys/statvfs.h>
+
+#include "../util.h"
+
+const char *
+disk_free(const char *path)
+{
+	struct statvfs fs;
+
+	if (statvfs(path, &fs) < 0) {
+		warn("statvfs '%s':", path);
+		return NULL;
+	}
+
+	return fmt_human(fs.f_frsize * fs.f_bavail, 1024);
+}
+
+const char *
+disk_perc(const char *path)
+{
+	struct statvfs fs;
+
+	if (statvfs(path, &fs) < 0) {
+		warn("statvfs '%s':", path);
+		return NULL;
+	}
+
+	return bprintf("%d", (int)(100 *
+	               (1.0f - ((float)fs.f_bavail / (float)fs.f_blocks))));
+}
+
+const char *
+disk_total(const char *path)
+{
+	struct statvfs fs;
+
+	if (statvfs(path, &fs) < 0) {
+		warn("statvfs '%s':", path);
+		return NULL;
+	}
+
+	return fmt_human(fs.f_frsize * fs.f_blocks, 1024);
+}
+
+const char *
+disk_used(const char *path)
+{
+	struct statvfs fs;
+
+	if (statvfs(path, &fs) < 0) {
+		warn("statvfs '%s':", path);
+		return NULL;
+	}
+
+	return fmt_human(fs.f_frsize * (fs.f_blocks - fs.f_bfree), 1024);
+}

components/entropy.c

@@ -0,0 +1,27 @@
+/* See LICENSE file for copyright and license details. */
+#if defined(__linux__)
+	#include <stdint.h>
+	#include <stdio.h>
+
+	#include "../util.h"
+
+	const char *
+	entropy(void)
+	{
+		uintmax_t num;
+
+		if (pscanf("/proc/sys/kernel/random/entropy_avail", "%ju", &num)
+		    != 1) {
+			return NULL;
+		}
+
+		return bprintf("%ju", num);
+	}
+#elif defined(__OpenBSD__) | defined(__FreeBSD__)
+	const char *
+	entropy(void)
+	{
+		/* Unicode Character 'INFINITY' (U+221E) */
+		return "\xe2\x88\x9e";
+	}
+#endif

components/hostname.c

@@ -0,0 +1,16 @@
+/* See LICENSE file for copyright and license details. */
+#include <stdio.h>
+#include <unistd.h>
+
+#include "../util.h"
+
+const char *
+hostname(void)
+{
+	if (gethostname(buf, sizeof(buf)) < 0) {
+		warn("gethostbyname:");
+		return NULL;
+	}
+
+	return buf;
+}

components/ip.c

@@ -0,0 +1,60 @@
+/* See LICENSE file for copyright and license details. */
+#include <ifaddrs.h>
+#include <netdb.h>
+#include <stdio.h>
+#include <string.h>
+#if defined(__OpenBSD__)
+	#include <sys/types.h>
+	#include <sys/socket.h>
+#elif defined(__FreeBSD__)
+	#include <netinet/in.h>
+	#include <sys/socket.h>
+#endif
+
+#include "../util.h"
+
+static const char *
+ip(const char *interface, unsigned short sa_family)
+{
+	struct ifaddrs *ifaddr, *ifa;
+	int s;
+	char host[NI_MAXHOST];
+
+	if (getifaddrs(&ifaddr) < 0) {
+		warn("getifaddrs:");
+		return NULL;
+	}
+
+	for (ifa = ifaddr; ifa != NULL; ifa = ifa->ifa_next) {
+		if (!ifa->ifa_addr) {
+			continue;
+		}
+		s = getnameinfo(ifa->ifa_addr, sizeof(struct sockaddr_in6),
+		                host, NI_MAXHOST, NULL, 0, NI_NUMERICHOST);
+		if (!strcmp(ifa->ifa_name, interface) &&
+		    (ifa->ifa_addr->sa_family == sa_family)) {
+			freeifaddrs(ifaddr);
+			if (s != 0) {
+				warn("getnameinfo: %s", gai_strerror(s));
+				return NULL;
+			}
+			return bprintf("%s", host);
+		}
+	}
+
+	freeifaddrs(ifaddr);
+
+	return NULL;
+}
+
+const char *
+ipv4(const char *interface)
+{
+	return ip(interface, AF_INET);
+}
+
+const char *
+ipv6(const char *interface)
+{
+	return ip(interface, AF_INET6);
+}

components/kernel_release.c

@@ -0,0 +1,18 @@
+/* See LICENSE file for copyright and license details. */
+#include <sys/utsname.h>
+#include <stdio.h>
+
+#include "../util.h"
+
+const char *
+kernel_release(void)
+{
+	struct utsname udata;
+
+	if (uname(&udata) < 0) {
+		warn("uname:");
+		return NULL;
+	}
+
+	return bprintf("%s", udata.release);
+}

components/keyboard_indicators.c

@@ -0,0 +1,48 @@
+/* See LICENSE file for copyright and license details. */
+#include <ctype.h>
+#include <stdio.h>
+#include <string.h>
+#include <X11/Xlib.h>
+
+#include "../util.h"
+
+/*
+ * fmt consists of uppercase or lowercase 'c' for caps lock and/or 'n' for num
+ * lock, each optionally followed by '?', in the order of indicators desired.
+ * If followed by '?', the letter with case preserved is included in the output
+ * if the corresponding indicator is on.  Otherwise, the letter is always
+ * included, lowercase when off and uppercase when on.
+ */
+const char *
+keyboard_indicators(const char *fmt)
+{
+	Display *dpy;
+	XKeyboardState state;
+	size_t fmtlen, i, n;
+	int togglecase, isset;
+	char key;
+
+	if (!(dpy = XOpenDisplay(NULL))) {
+		warn("XOpenDisplay: Failed to open display");
+		return NULL;
+	}
+	XGetKeyboardControl(dpy, &state);
+	XCloseDisplay(dpy);
+
+	fmtlen = strnlen(fmt, 4);
+	for (i = n = 0; i < fmtlen; i++) {
+		key = tolower(fmt[i]);
+		if (key != 'c' && key != 'n') {
+			continue;
+		}
+		togglecase = (i + 1 >= fmtlen || fmt[i + 1] != '?');
+		isset = (state.led_mask & (1 << (key == 'n')));
+		if (togglecase) {
+			buf[n++] = isset ? toupper(key) : key;
+		} else if (isset) {
+			buf[n++] = fmt[i];
+		}
+	}
+	buf[n] = 0;
+	return buf;
+}

components/keymap.c

@@ -0,0 +1,87 @@
+/* See LICENSE file for copyright and license details. */
+#include <ctype.h>
+#include <stdlib.h>
+#include <string.h>
+#include <X11/XKBlib.h>
+#include <X11/Xlib.h>
+
+#include "../util.h"
+
+static int
+valid_layout_or_variant(char *sym)
+{
+	size_t i;
+	/* invalid symbols from xkb rules config */
+	static const char *invalid[] = { "evdev", "inet", "pc", "base" };
+
+	for (i = 0; i < LEN(invalid); i++) {
+		if (!strncmp(sym, invalid[i], strlen(invalid[i]))) {
+			return 0;
+		}
+	}
+
+	return 1;
+}
+
+static char *
+get_layout(char *syms, int grp_num)
+{
+	char *tok, *layout;
+	int grp;
+
+	layout = NULL;
+	tok = strtok(syms, "+:");
+	for (grp = 0; tok && grp <= grp_num; tok = strtok(NULL, "+:")) {
+		if (!valid_layout_or_variant(tok)) {
+			continue;
+		} else if (strlen(tok) == 1 && isdigit(tok[0])) {
+			/* ignore :2, :3, :4 (additional layout groups) */
+			continue;
+		}
+		layout = tok;
+		grp++;
+	}
+
+	return layout;
+}
+
+const char *
+keymap(void)
+{
+	Display *dpy;
+	XkbDescRec *desc;
+	XkbStateRec state;
+	char *symbols, *layout;
+
+	layout = NULL;
+
+	if (!(dpy = XOpenDisplay(NULL))) {
+		warn("XOpenDisplay: Failed to open display");
+		return NULL;
+	}
+	if (!(desc = XkbAllocKeyboard())) {
+		warn("XkbAllocKeyboard: Failed to allocate keyboard");
+		goto end;
+	}
+	if (XkbGetNames(dpy, XkbSymbolsNameMask, desc)) {
+		warn("XkbGetNames: Failed to retrieve key symbols");
+		goto end;
+	}
+	if (XkbGetState(dpy, XkbUseCoreKbd, &state)) {
+		warn("XkbGetState: Failed to retrieve keyboard state");
+		goto end;
+	}
+	if (!(symbols = XGetAtomName(dpy, desc->names->symbols))) {
+		warn("XGetAtomName: Failed to get atom name");
+		goto end;
+	}
+	layout = (char *)bprintf("%s", get_layout(symbols, state.group));
+	XFree(symbols);
+end:
+	XkbFreeKeyboard(desc, XkbSymbolsNameMask, 1);
+	if (XCloseDisplay(dpy)) {
+		warn("XCloseDisplay: Failed to close display");
+	}
+
+	return layout;
+}

components/load_avg.c

@@ -0,0 +1,18 @@
+/* See LICENSE file for copyright and license details. */
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "../util.h"
+
+const char *
+load_avg(void)
+{
+	double avgs[3];
+
+	if (getloadavg(avgs, 3) < 0) {
+		warn("getloadavg: Failed to obtain load average");
+		return NULL;
+	}
+
+	return bprintf("%.2f %.2f %.2f", avgs[0], avgs[1], avgs[2]);
+}

components/netspeeds.c

@@ -0,0 +1,139 @@
+/* See LICENSE file for copyright and license details. */
+#include <stdio.h>
+#include <limits.h>
+
+#include "../util.h"
+
+#if defined(__linux__)
+	#include <stdint.h>
+
+	const char *
+	netspeed_rx(const char *interface)
+	{
+		uintmax_t oldrxbytes;
+		static uintmax_t rxbytes;
+		extern const unsigned int interval;
+		char path[PATH_MAX];
+
+		oldrxbytes = rxbytes;
+
+		if (esnprintf(path, sizeof(path),
+		              "/sys/class/net/%s/statistics/rx_bytes",
+		              interface) < 0) {
+			return NULL;
+		}
+		if (pscanf(path, "%ju", &rxbytes) != 1) {
+			return NULL;
+		}
+		if (oldrxbytes == 0) {
+			return NULL;
+		}
+
+		return fmt_human((rxbytes - oldrxbytes) * 1000 / interval,
+		                 1024);
+	}
+
+	const char *
+	netspeed_tx(const char *interface)
+	{
+		uintmax_t oldtxbytes;
+		static uintmax_t txbytes;
+		extern const unsigned int interval;
+		char path[PATH_MAX];
+
+		oldtxbytes = txbytes;
+
+		if (esnprintf(path, sizeof(path),
+		              "/sys/class/net/%s/statistics/tx_bytes",
+		              interface) < 0) {
+			return NULL;
+		}
+		if (pscanf(path, "%ju", &txbytes) != 1) {
+			return NULL;
+		}
+		if (oldtxbytes == 0) {
+			return NULL;
+		}
+
+		return fmt_human((txbytes - oldtxbytes) * 1000 / interval,
+		                 1024);
+	}
+#elif defined(__OpenBSD__) | defined(__FreeBSD__)
+	#include <string.h>
+	#include <ifaddrs.h>
+	#include <sys/types.h>
+	#include <sys/socket.h>
+	#include <net/if.h>
+
+	const char *
+	netspeed_rx(const char *interface)
+	{
+		struct ifaddrs *ifal, *ifa;
+		struct if_data *ifd;
+		uintmax_t oldrxbytes;
+		static uintmax_t rxbytes;
+		extern const unsigned int interval;
+		int if_ok = 0;
+
+		oldrxbytes = rxbytes;
+
+		if (getifaddrs(&ifal) == -1) {
+			warn("getifaddrs failed");
+			return NULL;
+		}
+		rxbytes = 0;
+		for (ifa = ifal; ifa; ifa = ifa->ifa_next) {
+			if (!strcmp(ifa->ifa_name, interface) &&
+			   (ifd = (struct if_data *)ifa->ifa_data)) {
+				rxbytes += ifd->ifi_ibytes, if_ok = 1;
+			}
+		}
+		freeifaddrs(ifal);
+		if (!if_ok) {
+			warn("reading 'if_data' failed");
+			return NULL;
+		}
+		if (oldrxbytes == 0) {
+			return NULL;
+		}
+
+		return fmt_human((rxbytes - oldrxbytes) * 1000 / interval,
+		                 1024);
+	}
+
+	const char *
+	netspeed_tx(const char *interface)
+	{
+		struct ifaddrs *ifal, *ifa;
+		struct if_data *ifd;
+		uintmax_t oldtxbytes;
+		static uintmax_t txbytes;
+		extern const unsigned int interval;
+		int if_ok = 0;
+
+		oldtxbytes = txbytes;
+
+		if (getifaddrs(&ifal) == -1) {
+			warn("getifaddrs failed");
+			return NULL;
+		}
+		txbytes = 0;
+		for (ifa = ifal; ifa; ifa = ifa->ifa_next) {
+			if (!strcmp(ifa->ifa_name, interface) &&
+			   (ifd = (struct if_data *)ifa->ifa_data)) {
+				txbytes += ifd->ifi_obytes, if_ok = 1;
+			}
+		}
+		freeifaddrs(ifal);
+		if (!if_ok) {
+			warn("reading 'if_data' failed");
+			return NULL;
+		}
+		if (oldtxbytes == 0) {
+			return NULL;
+		}
+
+		return fmt_human((txbytes - oldtxbytes) * 1000 / interval,
+		                 1024);
+	}
+#endif

components/num_files.c

@@ -0,0 +1,31 @@
+/* See LICENSE file for copyright and license details. */
+#include <dirent.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "../util.h"
+
+const char *
+num_files(const char *path)
+{
+	struct dirent *dp;
+	DIR *fd;
+	int num;
+
+	if (!(fd = opendir(path))) {
+		warn("opendir '%s':", path);
+		return NULL;
+	}
+
+	num = 0;
+	while ((dp = readdir(fd))) {
+		if (!strcmp(dp->d_name, ".") || !strcmp(dp->d_name, "..")) {
+			continue; /* skip self and parent */
+		}
+		num++;
+	}
+
+	closedir(fd);
+
+	return bprintf("%d", num);
+}

components/ram.c

@@ -0,0 +1,222 @@
+/* See LICENSE file for copyright and license details. */
+#include <stdio.h>
+
+#include "../util.h"
+
+#if defined(__linux__)
+	#include <stdint.h>
+
+	const char *
+	ram_free(void)
+	{
+		uintmax_t free;
+
+		if (pscanf("/proc/meminfo",
+		           "MemTotal: %ju kB\n"
+		           "MemFree: %ju kB\n"
+		           "MemAvailable: %ju kB\n",
+		           &free, &free, &free) != 3) {
+			return NULL;
+		}
+
+		return fmt_human(free * 1024, 1024);
+	}
+
+	const char *
+	ram_perc(void)
+	{
+		uintmax_t total, free, buffers, cached;
+
+		if (pscanf("/proc/meminfo",
+		           "MemTotal: %ju kB\n"
+		           "MemFree: %ju kB\n"
+		           "MemAvailable: %ju kB\n"
+		           "Buffers: %ju kB\n"
+		           "Cached: %ju kB\n",
+		           &total, &free, &buffers, &buffers, &cached) != 5) {
+			return NULL;
+		}
+
+		if (total == 0) {
+			return NULL;
+		}
+
+		return bprintf("%d", 100 * ((total - free) - (buffers + cached))
+                               / total);
+	}
+
+	const char *
+	ram_total(void)
+	{
+		uintmax_t total;
+
+		if (pscanf("/proc/meminfo", "MemTotal: %ju kB\n", &total)
+		    != 1) {
+			return NULL;
+		}
+
+		return fmt_human(total * 1024, 1024);
+	}
+
+	const char *
+	ram_used(void)
+	{
+		uintmax_t total, free, buffers, cached;
+
+		if (pscanf("/proc/meminfo",
+		           "MemTotal: %ju kB\n"
+		           "MemFree: %ju kB\n"
+		           "MemAvailable: %ju kB\n"
+		           "Buffers: %ju kB\n"
+		           "Cached: %ju kB\n",
+		           &total, &free, &buffers, &buffers, &cached) != 5) {
+			return NULL;
+		}
+
+		return fmt_human((total - free - buffers - cached) * 1024,
+		                 1024);
+	}
+#elif defined(__OpenBSD__)
+	#include <stdlib.h>
+	#include <sys/sysctl.h>
+	#include <sys/types.h>
+	#include <unistd.h>
+
+	#define LOG1024 10
+	#define pagetok(size, pageshift) (size_t)(size << (pageshift - LOG1024))
+
+	inline int
+	load_uvmexp(struct uvmexp *uvmexp)
+	{
+		int uvmexp_mib[] = {CTL_VM, VM_UVMEXP};
+		size_t size;
+
+		size = sizeof(*uvmexp);
+
+		if (sysctl(uvmexp_mib, 2, uvmexp, &size, NULL, 0) >= 0) {
+			return 1;
+		}
+
+		return 0;
+	}
+
+	const char *
+	ram_free(void)
+	{
+		struct uvmexp uvmexp;
+		int free_pages;
+
+		if (load_uvmexp(&uvmexp)) {
+			free_pages = uvmexp.npages - uvmexp.active;
+			return fmt_human(pagetok(free_pages, uvmexp.pageshift) *
+			                 1024, 1024);
+		}
+
+		return NULL;
+	}
+
+	const char *
+	ram_perc(void)
+	{
+		struct uvmexp uvmexp;
+		int percent;
+
+		if (load_uvmexp(&uvmexp)) {
+			percent = uvmexp.active * 100 / uvmexp.npages;
+			return bprintf("%d", percent);
+		}
+
+		return NULL;
+	}
+
+	const char *
+	ram_total(void)
+	{
+		struct uvmexp uvmexp;
+
+		if (load_uvmexp(&uvmexp)) {
+			return fmt_human(pagetok(uvmexp.npages,
+			                         uvmexp.pageshift) * 1024,
+			                 1024);
+		}
+
+		return NULL;
+	}
+
+	const char *
+	ram_used(void)
+	{
+		struct uvmexp uvmexp;
+
+		if (load_uvmexp(&uvmexp)) {
+			return fmt_human(pagetok(uvmexp.active,
+			                         uvmexp.pageshift) * 1024,
+			                 1024);
+		}
+
+		return NULL;
+	}
+#elif defined(__FreeBSD__)
+	#include <sys/sysctl.h>
+	#include <sys/vmmeter.h>
+	#include <unistd.h>
+	#include <vm/vm_param.h>
+
+	const char *
+	ram_free(void) {
+		struct vmtotal vm_stats;
+		int mib[] = {CTL_VM, VM_TOTAL};
+		size_t len;
+
+		len = sizeof(struct vmtotal);
+		if (sysctl(mib, 2, &vm_stats, &len, NULL, 0) == -1
+				|| !len)
+			return NULL;
+
+		return fmt_human(vm_stats.t_free * getpagesize(), 1024);
+	}
+
+	const char *
+	ram_total(void) {
+		long npages;
+		size_t len;
+
+		len = sizeof(npages);
+		if (sysctlbyname("vm.stats.vm.v_page_count", &npages, &len, NULL, 0) == -1
+				|| !len)
+			return NULL;
+
+		return fmt_human(npages * getpagesize(), 1024);
+	}
+
+	const char *
+	ram_perc(void) {
+		long npages;
+		long active;
+		size_t len;
+
+		len = sizeof(npages);
+		if (sysctlbyname("vm.stats.vm.v_page_count", &npages, &len, NULL, 0) == -1
+				|| !len)
+			return NULL;
+
+		if (sysctlbyname("vm.stats.vm.v_active_count", &active, &len, NULL, 0) == -1
+				|| !len)
+			return NULL;
+
+		return bprintf("%d", active * 100 / npages);
+	}
+
+	const char *
+	ram_used(void) {
+		long active;
+		size_t len;
+
+		len = sizeof(active);
+		if (sysctlbyname("vm.stats.vm.v_active_count", &active, &len, NULL, 0) == -1
+				|| !len)
+			return NULL;
+
+		return fmt_human(active * getpagesize(), 1024);
+	}
+#endif

components/run_command.c

@@ -0,0 +1,30 @@
+/* See LICENSE file for copyright and license details. */
+#include <stdio.h>
+#include <string.h>
+
+#include "../util.h"
+
+const char *
+run_command(const char *cmd)
+{
+	char *p;
+	FILE *fp;
+
+	if (!(fp = popen(cmd, "r"))) {
+		warn("popen '%s':", cmd);
+		return NULL;
+	}
+	p = fgets(buf, sizeof(buf) - 1, fp);
+	if (pclose(fp) < 0) {
+		warn("pclose '%s':", cmd);
+		return NULL;
+	}
+	if (!p) {
+		return NULL;
+	}
+	if ((p = strrchr(buf, '\n'))) {
+		p[0] = '\0';
+	}
+
+	return buf[0] ? buf : NULL;
+}

components/separator.c

@@ -0,0 +1,10 @@
+/* See LICENSE file for copyright and license details. */
+#include <stdio.h>
+
+#include "../util.h"
+
+const char *
+separator(const char *separator)
+{
+    return separator;
+}

components/swap.c

@@ -0,0 +1,284 @@
+/* See LICENSE file for copyright and license details. */
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "../util.h"
+
+#if defined(__linux__)
+	static int
+	get_swap_info(long *s_total, long *s_free, long *s_cached)
+	{
+		FILE *fp;
+		struct {
+			const char *name;
+			const size_t len;
+			long *var;
+		} ent[] = {
+			{ "SwapTotal",  sizeof("SwapTotal") - 1,  s_total  },
+			{ "SwapFree",   sizeof("SwapFree") - 1,   s_free   },
+			{ "SwapCached", sizeof("SwapCached") - 1, s_cached },
+		};
+		size_t line_len = 0, i, left;
+		char *line = NULL;
+
+		/* get number of fields we want to extract */
+		for (i = 0, left = 0; i < LEN(ent); i++) {
+			if (ent[i].var) {
+				left++;
+			}
+		}
+
+		if (!(fp = fopen("/proc/meminfo", "r"))) {
+			warn("fopen '/proc/meminfo':");
+			return 1;
+		}
+
+		/* read file line by line and extract field information */
+		while (left > 0 && getline(&line, &line_len, fp) >= 0) {
+			for (i = 0; i < LEN(ent); i++) {
+				if (ent[i].var &&
+				    !strncmp(line, ent[i].name, ent[i].len)) {
+					sscanf(line + ent[i].len + 1,
+					       "%ld kB\n", ent[i].var);
+					left--;
+					break;
+				}
+			}
+		}
+		free(line);
+		if (ferror(fp)) {
+			warn("getline '/proc/meminfo':");
+			return 1;
+		}
+
+		fclose(fp);
+		return 0;
+	}
+
+	const char *
+	swap_free(void)
+	{
+		long free;
+
+		if (get_swap_info(NULL, &free, NULL)) {
+			return NULL;
+		}
+
+		return fmt_human(free * 1024, 1024);
+	}
+
+	const char *
+	swap_perc(void)
+	{
+		long total, free, cached;
+
+		if (get_swap_info(&total, &free, &cached) || total == 0) {
+			return NULL;
+		}
+
+		return bprintf("%d", 100 * (total - free - cached) / total);
+	}
+
+	const char *
+	swap_total(void)
+	{
+		long total;
+
+		if (get_swap_info(&total, NULL, NULL)) {
+			return NULL;
+		}
+
+		return fmt_human(total * 1024, 1024);
+	}
+
+	const char *
+	swap_used(void)
+	{
+		long total, free, cached;
+
+		if (get_swap_info(&total, &free, &cached)) {
+			return NULL;
+		}
+
+		return fmt_human((total - free - cached) * 1024, 1024);
+	}
+#elif defined(__OpenBSD__)
+	#include <stdlib.h>
+	#include <sys/swap.h>
+	#include <sys/types.h>
+	#include <unistd.h>
+
+	static int
+	getstats(int *total, int *used)
+	{
+		struct swapent *sep, *fsep;
+		int rnswap, nswap, i;
+
+		if ((nswap = swapctl(SWAP_NSWAP, 0, 0)) < 1) {
+			warn("swaptctl 'SWAP_NSWAP':");
+			return 1;
+		}
+		if (!(fsep = sep = calloc(nswap, sizeof(*sep)))) {
+			warn("calloc 'nswap':");
+			return 1;
+		}
+		if ((rnswap = swapctl(SWAP_STATS, (void *)sep, nswap)) < 0) {
+			warn("swapctl 'SWAP_STATA':");
+			return 1;
+		}
+		if (nswap != rnswap) {
+			warn("getstats: SWAP_STATS != SWAP_NSWAP");
+			return 1;
+		}
+
+		*total = 0;
+		*used = 0;
+
+		for (i = 0; i < rnswap; i++) {
+			*total += sep->se_nblks >> 1;
+			*used += sep->se_inuse >> 1;
+		}
+
+		free(fsep);
+
+		return 0;
+	}
+
+	const char *
+	swap_free(void)
+	{
+		int total, used;
+
+		if (getstats(&total, &used)) {
+			return NULL;
+		}
+
+		return fmt_human((total - used) * 1024, 1024);
+	}
+
+	const char *
+	swap_perc(void)
+	{
+		int total, used;
+
+		if (getstats(&total, &used)) {
+			return NULL;
+		}
+
+		if (total == 0) {
+			return NULL;
+		}
+
+		return bprintf("%d", 100 * used / total);
+	}
+
+	const char *
+	swap_total(void)
+	{
+		int total, used;
+
+		if (getstats(&total, &used)) {
+			return NULL;
+		}
+
+		return fmt_human(total * 1024, 1024);
+	}
+
+	const char *
+	swap_used(void)
+	{
+		int total, used;
+
+		if (getstats(&total, &used)) {
+			return NULL;
+		}
+
+		return fmt_human(used * 1024, 1024);
+	}
+#elif defined(__FreeBSD__)
+	#include <stdlib.h>
+	#include <sys/types.h>
+	#include <fcntl.h>
+	#include <unistd.h>
+	#include <kvm.h>
+
+	static int getswapinfo(struct kvm_swap *swap_info, size_t size)
+	{
+		kvm_t *kd;
+
+		kd = kvm_openfiles(NULL, "/dev/null", NULL, 0, NULL);
+		if(kd == NULL) {
+			warn("kvm_openfiles '/dev/null':");
+			return 0;
+		}
+
+		if(kvm_getswapinfo(kd, swap_info, size, 0 /* Unused flags */) == -1) {
+			warn("kvm_getswapinfo:");
+			kvm_close(kd);
+			return 0;
+		}
+
+		kvm_close(kd);
+		return 1;
+	}
+
+	const char *
+	swap_free(void)
+	{
+		struct kvm_swap swap_info[1];
+		long used, total;
+
+		if(!getswapinfo(swap_info, 1))
+			return NULL;
+
+		total = swap_info[0].ksw_total;
+		used = swap_info[0].ksw_used;
+
+		return fmt_human((total - used) * getpagesize(), 1024);
+	}
+
+	const char *
+	swap_perc(void)
+	{
+		struct kvm_swap swap_info[1];
+		long used, total;
+
+		if(!getswapinfo(swap_info, 1))
+			return NULL;
+
+		total = swap_info[0].ksw_total;
+		used = swap_info[0].ksw_used;
+
+		return bprintf("%d", used * 100 / total);
+	}
+
+	const char *
+	swap_total(void)
+	{
+		struct kvm_swap swap_info[1];
+		long total;
+
+		if(!getswapinfo(swap_info, 1))
+			return NULL;
+
+		total = swap_info[0].ksw_total;
+
+		return fmt_human(total * getpagesize(), 1024);
+	}
+
+	const char *
+	swap_used(void)
+	{
+		struct kvm_swap swap_info[1];
+		long used;
+
+		if(!getswapinfo(swap_info, 1))
+			return NULL;
+
+		used = swap_info[0].ksw_used;
+
+		return fmt_human(used * getpagesize(), 1024);
+	}
+#endif

components/temperature.c

@@ -0,0 +1,71 @@
+/* See LICENSE file for copyright and license details. */
+#include <stddef.h>
+
+#include "../util.h"
+
+
+#if defined(__linux__)
+	#include <stdint.h>
+
+	const char *
+	temp(const char *file)
+	{
+		uintmax_t temp;
+
+		if (pscanf(file, "%ju", &temp) != 1) {
+			return NULL;
+		}
+
+		return bprintf("%ju", temp / 1000);
+	}
+#elif defined(__OpenBSD__)
+	#include <stdio.h>
+	#include <sys/time.h> /* before <sys/sensors.h> for struct timeval */
+	#include <sys/sensors.h>
+	#include <sys/sysctl.h>
+
+	const char *
+	temp(const char *unused)
+	{
+		int mib[5];
+		size_t size;
+		struct sensor temp;
+
+		mib[0] = CTL_HW;
+		mib[1] = HW_SENSORS;
+		mib[2] = 0; /* cpu0 */
+		mib[3] = SENSOR_TEMP;
+		mib[4] = 0; /* temp0 */
+
+		size = sizeof(temp);
+
+		if (sysctl(mib, 5, &temp, &size, NULL, 0) < 0) {
+			warn("sysctl 'SENSOR_TEMP':");
+			return NULL;
+		}
+
+		/* kelvin to celsius */
+		return bprintf("%d", (int)((float)(temp.value-273150000) / 1E6));
+	}
+#elif defined(__FreeBSD__)
+	#include <stdio.h>
+	#include <stdlib.h>
+	#include <sys/sysctl.h>
+
+	const char *
+	temp(const char *zone)
+	{
+		char buf[256];
+		int temp;
+		size_t len;
+
+		len = sizeof(temp);
+		snprintf(buf, sizeof(buf), "hw.acpi.thermal.%s.temperature", zone);
+		if (sysctlbyname(buf, &temp, &len, NULL, 0) == -1
+				|| !len)
+			return NULL;
+
+		/* kelvin to decimal celcius */
+		return bprintf("%d.%d", (temp - 2731) / 10, abs((temp - 2731) % 10));
+	}
+#endif

components/uptime.c

@@ -0,0 +1,33 @@
+/* See LICENSE file for copyright and license details. */
+#include <stdint.h>
+#include <stdio.h>
+#include <time.h>
+
+#include "../util.h"
+
+#if defined(CLOCK_BOOTTIME)
+	#define UPTIME_FLAG CLOCK_BOOTTIME
+#elif defined(CLOCK_UPTIME)
+	#define UPTIME_FLAG CLOCK_UPTIME
+#else
+	#define UPTIME_FLAG CLOCK_MONOTONIC
+#endif
+
+const char *
+uptime(void)
+{
+	char warn_buf[256];
+	uintmax_t h, m;
+	struct timespec uptime;
+
+	if (clock_gettime(UPTIME_FLAG, &uptime) < 0) {
+		snprintf(warn_buf, 256, "clock_gettime %d", UPTIME_FLAG);
+		warn(warn_buf);
+		return NULL;
+	}
+
+	h = uptime.tv_sec / 3600;
+	m = uptime.tv_sec % 3600 / 60;
+
+	return bprintf("%juh %jum", h, m);
+}

components/user.c

@@ -0,0 +1,32 @@
+/* See LICENSE file for copyright and license details. */
+#include <pwd.h>
+#include <stdio.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "../util.h"
+
+const char *
+gid(void)
+{
+	return bprintf("%d", getgid());
+}
+
+const char *
+username(void)
+{
+	struct passwd *pw;
+
+	if (!(pw = getpwuid(geteuid()))) {
+		warn("getpwuid '%d':", geteuid());
+		return NULL;
+	}
+
+	return bprintf("%s", pw->pw_name);
+}
+
+const char *
+uid(void)
+{
+	return bprintf("%d", geteuid());
+}

components/volume.c

@@ -0,0 +1,217 @@
+/* See LICENSE file for copyright and license details. */
+#include <fcntl.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <unistd.h>
+
+#include "../util.h"
+
+#if defined(__OpenBSD__)
+	#include <sys/queue.h>
+	#include <poll.h>
+	#include <sndio.h>
+	#include <stdlib.h>
+
+	struct control {
+		LIST_ENTRY(control)	next;
+		unsigned int		addr;
+	#define CTRL_NONE	0
+	#define CTRL_LEVEL	1
+	#define CTRL_MUTE	2
+		unsigned int		type;
+		unsigned int		maxval;
+		unsigned int		val;
+	};
+
+	static LIST_HEAD(, control) controls = LIST_HEAD_INITIALIZER(controls);
+	static struct pollfd *pfds;
+	static struct sioctl_hdl *hdl;
+	static int initialized;
+
+	/*
+	 * Call-back to obtain the description of all audio controls.
+	 */
+	static void
+	ondesc(void *unused, struct sioctl_desc *desc, int val)
+	{
+		struct control *c, *ctmp;
+		unsigned int type = CTRL_NONE;
+
+		if (desc == NULL)
+			return;
+
+		/* Delete existing audio control with the same address. */
+		LIST_FOREACH_SAFE(c, &controls, next, ctmp) {
+			if (desc->addr == c->addr) {
+				LIST_REMOVE(c, next);
+				free(c);
+				break;
+			}
+		}
+
+		/* Only match output.level and output.mute audio controls. */
+		if (desc->group[0] != 0 ||
+		    strcmp(desc->node0.name, "output") != 0)
+			return;
+		if (desc->type == SIOCTL_NUM &&
+		    strcmp(desc->func, "level") == 0)
+			type = CTRL_LEVEL;
+		else if (desc->type == SIOCTL_SW &&
+			 strcmp(desc->func, "mute") == 0)
+			type = CTRL_MUTE;
+		else
+			return;
+
+		c = malloc(sizeof(struct control));
+		if (c == NULL) {
+			warn("sndio: failed to allocate audio control\n");
+			return;
+		}
+
+		c->addr = desc->addr;
+		c->type = type;
+		c->maxval = desc->maxval;
+		c->val = val;
+		LIST_INSERT_HEAD(&controls, c, next);
+	}
+
+	/*
+	 * Call-back invoked whenever an audio control changes.
+	 */
+	static void
+	onval(void *unused, unsigned int addr, unsigned int val)
+	{
+		struct control *c;
+
+		LIST_FOREACH(c, &controls, next) {
+			if (c->addr == addr)
+				break;
+		}
+		c->val = val;
+	}
+
+	static void
+	cleanup(void)
+	{
+		struct control *c;
+
+		if (hdl) {
+			sioctl_close(hdl);
+			hdl = NULL;
+		}
+
+		free(pfds);
+		pfds = NULL;
+
+		while (!LIST_EMPTY(&controls)) {
+			c = LIST_FIRST(&controls);
+			LIST_REMOVE(c, next);
+			free(c);
+		}
+	}
+
+	static int
+	init(void)
+	{
+		hdl = sioctl_open(SIO_DEVANY, SIOCTL_READ, 0);
+		if (hdl == NULL) {
+			warn("sndio: cannot open device");
+			goto failed;
+		}
+
+		if (!sioctl_ondesc(hdl, ondesc, NULL)) {
+			warn("sndio: cannot set control description call-back");
+			goto failed;
+		}
+
+		if (!sioctl_onval(hdl, onval, NULL)) {
+			warn("sndio: cannot set control values call-back");
+			goto failed;
+		}
+
+		pfds = calloc(sioctl_nfds(hdl), sizeof(struct pollfd));
+		if (pfds == NULL) {
+			warn("sndio: cannot allocate pollfd structures");
+			goto failed;
+		}
+
+		return 1;
+	failed:
+		cleanup();
+		return 0;
+	}
+
+	const char *
+	vol_perc(const char *unused)
+	{
+		struct control *c;
+		int n, v, value;
+
+		if (!initialized)
+			initialized = init();
+
+		if (hdl == NULL)
+			return NULL;
+
+		n = sioctl_pollfd(hdl, pfds, POLLIN);
+		if (n > 0) {
+			n = poll(pfds, n, 0);
+			if (n > 0) {
+				if (sioctl_revents(hdl, pfds) & POLLHUP) {
+					warn("sndio: disconnected");
+					cleanup();
+					return NULL;
+				}
+			}
+		}
+
+		value = 100;
+		LIST_FOREACH(c, &controls, next) {
+			if (c->type == CTRL_MUTE && c->val == 1)
+				value = 0;
+			else if (c->type == CTRL_LEVEL) {
+				v = (c->val * 100 + c->maxval / 2) / c->maxval;
+				/* For multiple channels return the minimum. */
+				if (v < value)
+					value = v;
+			}
+		}
+
+		return bprintf("%d", value);
+	}
+#else
+	#include <sys/soundcard.h>
+
+	const char *
+	vol_perc(const char *card)
+	{
+		size_t i;
+		int v, afd, devmask;
+		char *vnames[] = SOUND_DEVICE_NAMES;
+
+		if ((afd = open(card, O_RDONLY | O_NONBLOCK)) < 0) {
+			warn("open '%s':", card);
+			return NULL;
+		}
+
+		if (ioctl(afd, (int)SOUND_MIXER_READ_DEVMASK, &devmask) < 0) {
+			warn("ioctl 'SOUND_MIXER_READ_DEVMASK':");
+			close(afd);
+			return NULL;
+		}
+		for (i = 0; i < LEN(vnames); i++) {
+			if (devmask & (1 << i) && !strcmp("vol", vnames[i])) {
+				if (ioctl(afd, MIXER_READ(i), &v) < 0) {
+					warn("ioctl 'MIXER_READ(%ld)':", i);
+					close(afd);
+					return NULL;
+				}
+			}
+		}
+
+		close(afd);
+
+		return bprintf("%d", v & 0xff);
+	}
+#endif

components/wifi.c

@@ -0,0 +1,272 @@
+/* See LICENSE file for copyright and license details. */
+#include <ifaddrs.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/socket.h>
+#include <unistd.h>
+
+#include "../util.h"
+
+#define RSSI_TO_PERC(rssi) \
+			rssi >= -50 ? 100 : \
+			(rssi <= -100 ? 0 : \
+			(2 * (rssi + 100)))
+
+#if defined(__linux__)
+	#include <limits.h>
+	#include <linux/wireless.h>
+
+	const char *
+	wifi_perc(const char *interface)
+	{
+		int cur;
+		size_t i;
+		char *p, *datastart;
+		char path[PATH_MAX];
+		char status[5];
+		FILE *fp;
+
+		if (esnprintf(path, sizeof(path), "/sys/class/net/%s/operstate",
+		              interface) < 0) {
+			return NULL;
+		}
+		if (!(fp = fopen(path, "r"))) {
+			warn("fopen '%s':", path);
+			return NULL;
+		}
+		p = fgets(status, 5, fp);
+		fclose(fp);
+		if (!p || strcmp(status, "up\n") != 0) {
+			return NULL;
+		}
+
+		if (!(fp = fopen("/proc/net/wireless", "r"))) {
+			warn("fopen '/proc/net/wireless':");
+			return NULL;
+		}
+
+		for (i = 0; i < 3; i++) {
+			if (!(p = fgets(buf, sizeof(buf) - 1, fp)))
+				break;
+		}
+		fclose(fp);
+		if (i < 2 || !p) {
+			return NULL;
+		}
+
+		if (!(datastart = strstr(buf, interface))) {
+			return NULL;
+		}
+
+		datastart = (datastart+(strlen(interface)+1));
+		sscanf(datastart + 1, " %*d   %d  %*d  %*d\t\t  %*d\t   "
+		       "%*d\t\t%*d\t\t %*d\t  %*d\t\t %*d", &cur);
+
+		/* 70 is the max of /proc/net/wireless */
+		return bprintf("%d", (int)((float)cur / 70 * 100));
+	}
+
+	const char *
+	wifi_essid(const char *interface)
+	{
+		static char id[IW_ESSID_MAX_SIZE+1];
+		int sockfd;
+		struct iwreq wreq;
+
+		memset(&wreq, 0, sizeof(struct iwreq));
+		wreq.u.essid.length = IW_ESSID_MAX_SIZE+1;
+		if (esnprintf(wreq.ifr_name, sizeof(wreq.ifr_name), "%s",
+		              interface) < 0) {
+			return NULL;
+		}
+
+		if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
+			warn("socket 'AF_INET':");
+			return NULL;
+		}
+		wreq.u.essid.pointer = id;
+		if (ioctl(sockfd,SIOCGIWESSID, &wreq) < 0) {
+			warn("ioctl 'SIOCGIWESSID':");
+			close(sockfd);
+			return NULL;
+		}
+
+		close(sockfd);
+
+		if (!strcmp(id, "")) {
+			return NULL;
+		}
+
+		return id;
+	}
+#elif defined(__OpenBSD__)
+	#include <net/if.h>
+	#include <net/if_media.h>
+	#include <net80211/ieee80211.h>
+	#include <sys/select.h> /* before <sys/ieee80211_ioctl.h> for NBBY */
+	#include <net80211/ieee80211_ioctl.h>
+	#include <stdlib.h>
+	#include <sys/types.h>
+
+	static int
+	load_ieee80211_nodereq(const char *interface, struct ieee80211_nodereq *nr)
+	{
+		struct ieee80211_bssid bssid;
+		int sockfd;
+		uint8_t zero_bssid[IEEE80211_ADDR_LEN];
+
+		memset(&bssid, 0, sizeof(bssid));
+		memset(nr, 0, sizeof(struct ieee80211_nodereq));
+		if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
+			warn("socket 'AF_INET':");
+			return 0;
+		}
+		strlcpy(bssid.i_name, interface, sizeof(bssid.i_name));
+		if ((ioctl(sockfd, SIOCG80211BSSID, &bssid)) < 0) {
+			warn("ioctl 'SIOCG80211BSSID':");
+			close(sockfd);
+			return 0;
+		}
+		memset(&zero_bssid, 0, sizeof(zero_bssid));
+		if (memcmp(bssid.i_bssid, zero_bssid,
+		    IEEE80211_ADDR_LEN) == 0) {
+			close(sockfd);
+			return 0;
+		}
+		strlcpy(nr->nr_ifname, interface, sizeof(nr->nr_ifname));
+		memcpy(&nr->nr_macaddr, bssid.i_bssid, sizeof(nr->nr_macaddr));
+		if ((ioctl(sockfd, SIOCG80211NODE, nr)) < 0 && nr->nr_rssi) {
+			warn("ioctl 'SIOCG80211NODE':");
+			close(sockfd);
+			return 0;
+		}
+
+		return close(sockfd), 1;
+	}
+
+	const char *
+	wifi_perc(const char *interface)
+	{
+		struct ieee80211_nodereq nr;
+		int q;
+
+		if (load_ieee80211_nodereq(interface, &nr)) {
+			if (nr.nr_max_rssi) {
+				q = IEEE80211_NODEREQ_RSSI(&nr);
+			} else {
+				q = RSSI_TO_PERC(nr.nr_rssi);
+			}
+			return bprintf("%d", q);
+		}
+
+		return NULL;
+	}
+
+	const char *
+	wifi_essid(const char *interface)
+	{
+		struct ieee80211_nodereq nr;
+
+		if (load_ieee80211_nodereq(interface, &nr)) {
+			return bprintf("%s", nr.nr_nwid);
+		}
+
+		return NULL;
+	}
+#elif defined(__FreeBSD__)
+	#include <net/if.h>
+	#include <net80211/ieee80211_ioctl.h>
+
+	int
+	load_ieee80211req(int sock, const char *interface, void *data, int type, size_t *len)
+	{
+		char warn_buf[256];
+		struct ieee80211req ireq;
+		memset(&ireq, 0, sizeof(ireq));
+		ireq.i_type = type;
+		ireq.i_data = (caddr_t) data;
+		ireq.i_len = *len;
+
+		strlcpy(ireq.i_name, interface, sizeof(ireq.i_name));
+		if (ioctl(sock, SIOCG80211, &ireq) < 0) {
+			snprintf(warn_buf,  sizeof(warn_buf),
+					"ioctl: 'SIOCG80211': %d", type);
+			warn(warn_buf);
+			return 0;
+		}
+
+		*len = ireq.i_len;
+		return 1;
+	}
+
+	const char *
+	wifi_perc(const char *interface)
+	{
+		union {
+			struct ieee80211req_sta_req sta;
+			uint8_t buf[24 * 1024];
+		} info;
+		uint8_t bssid[IEEE80211_ADDR_LEN];
+		int rssi_dbm;
+		int sockfd;
+		size_t len;
+		const char *fmt;
+
+		if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
+			warn("socket 'AF_INET':");
+			return NULL;
+		}
+
+		/* Retreive MAC address of interface */
+		len = IEEE80211_ADDR_LEN;
+		fmt = NULL;
+		if (load_ieee80211req(sockfd, interface, &bssid, IEEE80211_IOC_BSSID, &len))
+		{
+			/* Retrieve info on station with above BSSID */
+			memset(&info, 0, sizeof(info));
+			memcpy(info.sta.is_u.macaddr, bssid, sizeof(bssid));
+
+			len = sizeof(info);
+			if (load_ieee80211req(sockfd, interface, &info, IEEE80211_IOC_STA_INFO, &len)) {
+				rssi_dbm = info.sta.info[0].isi_noise +
+ 					         info.sta.info[0].isi_rssi / 2;
+
+				fmt = bprintf("%d", RSSI_TO_PERC(rssi_dbm));
+			}
+		}
+
+		close(sockfd);
+		return fmt;
+	}
+
+	const char *
+	wifi_essid(const char *interface)
+	{
+		char ssid[IEEE80211_NWID_LEN + 1];
+		size_t len;
+		int sockfd;
+		const char *fmt;
+
+		if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
+			warn("socket 'AF_INET':");
+			return NULL;
+		}
+
+		fmt = NULL;
+		len = sizeof(ssid);
+		memset(&ssid, 0, len);
+		if (load_ieee80211req(sockfd, interface, &ssid, IEEE80211_IOC_SSID, &len )) {
+			if (len < sizeof(ssid))
+				len += 1;
+			else
+				len = sizeof(ssid);
+
+			ssid[len - 1] = '\0';
+			fmt = bprintf("%s", ssid);
+		}
+
+		close(sockfd);
+		return fmt;
+	}
+#endif

config.def.h

@@ -0,0 +1,73 @@
+/* See LICENSE file for copyright and license details. */
+
+/* interval between updates (in ms) */
+const unsigned int interval = 1000;
+
+/* text to show if no value can be retrieved */
+static const char unknown_str[] = "n/a";
+
+/* maximum output string length */
+#define MAXLEN 2048
+
+/*
+ * function            description                     argument (example)
+ *
+ * battery_perc        battery percentage              battery name (BAT0)
+ *                                                     NULL on OpenBSD/FreeBSD
+ * battery_state       battery charging state          battery name (BAT0)
+ *                                                     NULL on OpenBSD/FreeBSD
+ * battery_remaining   battery remaining HH:MM         battery name (BAT0)
+ *                                                     NULL on OpenBSD/FreeBSD
+ * cpu_perc            cpu usage in percent            NULL
+ * cpu_freq            cpu frequency in MHz            NULL
+ * datetime            date and time                   format string (%F %T)
+ * disk_free           free disk space in GB           mountpoint path (/)
+ * disk_perc           disk usage in percent           mountpoint path (/)
+ * disk_total          total disk space in GB          mountpoint path (/")
+ * disk_used           used disk space in GB           mountpoint path (/)
+ * entropy             available entropy               NULL
+ * gid                 GID of current user             NULL
+ * hostname            hostname                        NULL
+ * ipv4                IPv4 address                    interface name (eth0)
+ * ipv6                IPv6 address                    interface name (eth0)
+ * kernel_release      `uname -r`                      NULL
+ * keyboard_indicators caps/num lock indicators        format string (c?n?)
+ *                                                     see keyboard_indicators.c
+ * keymap              layout (variant) of current     NULL
+ *                     keymap
+ * load_avg            load average                    NULL
+ * netspeed_rx         receive network speed           interface name (wlan0)
+ * netspeed_tx         transfer network speed          interface name (wlan0)
+ * num_files           number of files in a directory  path
+ *                                                     (/home/foo/Inbox/cur)
+ * ram_free            free memory in GB               NULL
+ * ram_perc            memory usage in percent         NULL
+ * ram_total           total memory size in GB         NULL
+ * ram_used            used memory in GB               NULL
+ * run_command         custom shell command            command (echo foo)
+ * separator           string to echo                  NULL
+ * swap_free           free swap in GB                 NULL
+ * swap_perc           swap usage in percent           NULL
+ * swap_total          total swap size in GB           NULL
+ * swap_used           used swap in GB                 NULL
+ * temp                temperature in degree celsius   sensor file
+ *                                                     (/sys/class/thermal/...)
+ *                                                     NULL on OpenBSD
+ *                                                     thermal zone on FreeBSD
+ *                                                     (tz0, tz1, etc.)
+ * uid                 UID of current user             NULL
+ * uptime              system uptime                   NULL
+ * username            username of current user        NULL
+ * vol_perc            OSS/ALSA volume in percent      mixer file (/dev/mixer)
+ *                                                     NULL on OpenBSD
+ * wifi_perc           WiFi signal in percent          interface name (wlan0)
+ * wifi_essid          WiFi ESSID                      interface name (wlan0)
+ */
+static const struct arg args[] = {
+	/* function format          argument */
+	{ cpu_perc, "[CPU %5s%%] ",    NULL },
+	{ ram_used, "[RAM %4s] ",      NULL },
+	{ username, "%3s@",            NULL },
+	{ hostname, "%2s ",            NULL },
+	{ datetime, "%s",           "%A %B %d %Y %r" },
+};

config.h

@@ -0,0 +1,73 @@
+/* See LICENSE file for copyright and license details. */
+
+/* interval between updates (in ms) */
+const unsigned int interval = 1000;
+
+/* text to show if no value can be retrieved */
+static const char unknown_str[] = "n/a";
+
+/* maximum output string length */
+#define MAXLEN 2048
+
+/*
+ * function            description                     argument (example)
+ *
+ * battery_perc        battery percentage              battery name (BAT0)
+ *                                                     NULL on OpenBSD/FreeBSD
+ * battery_state       battery charging state          battery name (BAT0)
+ *                                                     NULL on OpenBSD/FreeBSD
+ * battery_remaining   battery remaining HH:MM         battery name (BAT0)
+ *                                                     NULL on OpenBSD/FreeBSD
+ * cpu_perc            cpu usage in percent            NULL
+ * cpu_freq            cpu frequency in MHz            NULL
+ * datetime            date and time                   format string (%F %T)
+ * disk_free           free disk space in GB           mountpoint path (/)
+ * disk_perc           disk usage in percent           mountpoint path (/)
+ * disk_total          total disk space in GB          mountpoint path (/")
+ * disk_used           used disk space in GB           mountpoint path (/)
+ * entropy             available entropy               NULL
+ * gid                 GID of current user             NULL
+ * hostname            hostname                        NULL
+ * ipv4                IPv4 address                    interface name (eth0)
+ * ipv6                IPv6 address                    interface name (eth0)
+ * kernel_release      `uname -r`                      NULL
+ * keyboard_indicators caps/num lock indicators        format string (c?n?)
+ *                                                     see keyboard_indicators.c
+ * keymap              layout (variant) of current     NULL
+ *                     keymap
+ * load_avg            load average                    NULL
+ * netspeed_rx         receive network speed           interface name (wlan0)
+ * netspeed_tx         transfer network speed          interface name (wlan0)
+ * num_files           number of files in a directory  path
+ *                                                     (/home/foo/Inbox/cur)
+ * ram_free            free memory in GB               NULL
+ * ram_perc            memory usage in percent         NULL
+ * ram_total           total memory size in GB         NULL
+ * ram_used            used memory in GB               NULL
+ * run_command         custom shell command            command (echo foo)
+ * separator           string to echo                  NULL
+ * swap_free           free swap in GB                 NULL
+ * swap_perc           swap usage in percent           NULL
+ * swap_total          total swap size in GB           NULL
+ * swap_used           used swap in GB                 NULL
+ * temp                temperature in degree celsius   sensor file
+ *                                                     (/sys/class/thermal/...)
+ *                                                     NULL on OpenBSD
+ *                                                     thermal zone on FreeBSD
+ *                                                     (tz0, tz1, etc.)
+ * uid                 UID of current user             NULL
+ * uptime              system uptime                   NULL
+ * username            username of current user        NULL
+ * vol_perc            OSS/ALSA volume in percent      mixer file (/dev/mixer)
+ *                                                     NULL on OpenBSD
+ * wifi_perc           WiFi signal in percent          interface name (wlan0)
+ * wifi_essid          WiFi ESSID                      interface name (wlan0)
+ */
+static const struct arg args[] = {
+	/* function format          argument */
+	{ cpu_perc, "[CPU %5s%%] ",    NULL },
+	{ ram_used, "[RAM %4s] ",      NULL },
+	{ username, "%3s@",            NULL },
+	{ hostname, "%2s ",            NULL },
+	{ datetime, "%s",           "%A %B %d %Y %r" },
+};

config.mk

@@ -0,0 +1,22 @@
+# slstatus version
+VERSION = 0
+
+# customize below to fit your system
+
+# paths
+PREFIX = /usr/local
+MANPREFIX = $(PREFIX)/share/man
+
+X11INC = /usr/X11R6/include
+X11LIB = /usr/X11R6/lib
+
+# flags
+CPPFLAGS = -I$(X11INC) -D_DEFAULT_SOURCE
+CFLAGS   = -std=c99 -pedantic -Wall -Wextra -Os
+LDFLAGS  = -L$(X11LIB) -s
+# OpenBSD: add -lsndio
+# FreeBSD: add -lkvm
+LDLIBS   = -lX11
+
+# compiler and linker
+CC = cc

slstatus.1

@@ -0,0 +1,28 @@
+.Dd 2020-06-23
+.Dt SLSTATUS 1
+.Os
+.Sh NAME
+.Nm slstatus
+.Nd suckless status monitor
+.Sh SYNOPSIS
+.Nm
+.Op Fl s
+.Op Fl 1
+.Sh DESCRIPTION
+.Nm
+is a suckless status monitor for window managers that use WM_NAME (e.g. dwm) or
+stdin to fill the status bar.
+By default,
+.Nm
+outputs to WM_NAME.
+.Sh OPTIONS
+.Bl -tag -width Ds
+.It Fl s
+Write to stdout instead of WM_NAME.
+.It Fl 1
+Write once to stdout and quit.
+.El
+.Sh CUSTOMIZATION
+.Nm
+can be customized by creating a custom config.h and (re)compiling the source
+code. This keeps it fast, secure and simple.

slstatus.c

@@ -0,0 +1,141 @@
+/* See LICENSE file for copyright and license details. */
+#include <errno.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <X11/Xlib.h>
+
+#include "arg.h"
+#include "slstatus.h"
+#include "util.h"
+
+struct arg {
+	const char *(*func)();
+	const char *fmt;
+	const char *args;
+};
+
+char buf[1024];
+static volatile sig_atomic_t done;
+static Display *dpy;
+
+#include "config.h"
+
+static void
+terminate(const int signo)
+{
+	if (signo != SIGUSR1)
+		done = 1;
+}
+
+static void
+difftimespec(struct timespec *res, struct timespec *a, struct timespec *b)
+{
+	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) * 1E9;
+}
+
+static void
+usage(void)
+{
+	die("usage: %s [-s] [-1]", argv0);
+}
+
+int
+main(int argc, char *argv[])
+{
+	struct sigaction act;
+	struct timespec start, current, diff, intspec, wait;
+	size_t i, len;
+	int sflag, ret;
+	char status[MAXLEN];
+	const char *res;
+
+	sflag = 0;
+	ARGBEGIN {
+		case '1':
+			done = 1;
+			/* fallthrough */
+		case 's':
+			sflag = 1;
+			break;
+		default:
+			usage();
+	} ARGEND
+
+	if (argc) {
+		usage();
+	}
+
+	memset(&act, 0, sizeof(act));
+	act.sa_handler = terminate;
+	sigaction(SIGINT,  &act, NULL);
+	sigaction(SIGTERM, &act, NULL);
+	act.sa_flags |= SA_RESTART;
+	sigaction(SIGUSR1, &act, NULL);
+
+	if (!sflag && !(dpy = XOpenDisplay(NULL))) {
+		die("XOpenDisplay: Failed to open display");
+	}
+
+	do {
+		if (clock_gettime(CLOCK_MONOTONIC, &start) < 0) {
+			die("clock_gettime:");
+		}
+
+		status[0] = '\0';
+		for (i = len = 0; i < LEN(args); i++) {
+			if (!(res = args[i].func(args[i].args))) {
+				res = unknown_str;
+			}
+			if ((ret = esnprintf(status + len, sizeof(status) - len,
+			                    args[i].fmt, res)) < 0) {
+				break;
+			}
+			len += ret;
+		}
+
+		if (sflag) {
+			puts(status);
+			fflush(stdout);
+			if (ferror(stdout))
+				die("puts:");
+		} else {
+			if (XStoreName(dpy, DefaultRootWindow(dpy), status)
+                            < 0) {
+				die("XStoreName: Allocation failed");
+			}
+			XFlush(dpy);
+		}
+
+		if (!done) {
+			if (clock_gettime(CLOCK_MONOTONIC, &current) < 0) {
+				die("clock_gettime:");
+			}
+			difftimespec(&diff, &current, &start);
+
+			intspec.tv_sec = interval / 1000;
+			intspec.tv_nsec = (interval % 1000) * 1E6;
+			difftimespec(&wait, &intspec, &diff);
+
+			if (wait.tv_sec >= 0) {
+				if (nanosleep(&wait, NULL) < 0 &&
+				    errno != EINTR) {
+					die("nanosleep:");
+				}
+			}
+		}
+	} while (!done);
+
+	if (!sflag) {
+		XStoreName(dpy, DefaultRootWindow(dpy), NULL);
+		if (XCloseDisplay(dpy) < 0) {
+			die("XCloseDisplay: Failed to close display");
+		}
+	}
+
+	return 0;
+}

slstatus.h

@@ -0,0 +1,84 @@
+/* See LICENSE file for copyright and license details. */
+
+/* battery */
+const char *battery_perc(const char *);
+const char *battery_state(const char *);
+const char *battery_remaining(const char *);
+
+/* cpu */
+const char *cpu_freq(void);
+const char *cpu_perc(void);
+
+/* datetime */
+const char *datetime(const char *fmt);
+
+/* disk */
+const char *disk_free(const char *path);
+const char *disk_perc(const char *path);
+const char *disk_total(const char *path);
+const char *disk_used(const char *path);
+
+/* entropy */
+const char *entropy(void);
+
+/* hostname */
+const char *hostname(void);
+
+/* ip */
+const char *ipv4(const char *interface);
+const char *ipv6(const char *interface);
+
+/* kernel_release */
+const char *kernel_release(void);
+
+/* keyboard_indicators */
+const char *keyboard_indicators(void);
+
+/* keymap */
+const char *keymap(void);
+
+/* load_avg */
+const char *load_avg(void);
+
+/* netspeeds */
+const char *netspeed_rx(const char *interface);
+const char *netspeed_tx(const char *interface);
+
+/* num_files */
+const char *num_files(const char *path);
+
+/* ram */
+const char *ram_free(void);
+const char *ram_perc(void);
+const char *ram_total(void);
+const char *ram_used(void);
+
+/* run_command */
+const char *run_command(const char *cmd);
+
+/* separator */
+const char *separator(const char *separator);
+
+/* swap */
+const char *swap_free(void);
+const char *swap_perc(void);
+const char *swap_total(void);
+const char *swap_used(void);
+
+/* temperature */
+const char *temp(const char *);
+
+/* uptime */
+const char *uptime(void);
+
+/* user */
+const char *gid(void);
+const char *username(void);
+const char *uid(void);
+
+/* volume */
+const char *vol_perc(const char *card);
+
+/* wifi */
+const char *wifi_perc(const char *interface);
+const char *wifi_essid(const char *interface);

util.c

@@ -0,0 +1,146 @@
+/* See LICENSE file for copyright and license details. */
+#include <errno.h>
+#include <stdarg.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "util.h"
+
+char *argv0;
+
+static void
+verr(const char *fmt, va_list ap)
+{
+	if (argv0 && strncmp(fmt, "usage", sizeof("usage") - 1)) {
+		fprintf(stderr, "%s: ", argv0);
+	}
+
+	vfprintf(stderr, fmt, ap);
+
+	if (fmt[0] && fmt[strlen(fmt) - 1] == ':') {
+		fputc(' ', stderr);
+		perror(NULL);
+	} else {
+		fputc('\n', stderr);
+	}
+}
+
+void
+warn(const char *fmt, ...)
+{
+	va_list ap;
+
+	va_start(ap, fmt);
+	verr(fmt, ap);
+	va_end(ap);
+}
+
+void
+die(const char *fmt, ...)
+{
+	va_list ap;
+
+	va_start(ap, fmt);
+	verr(fmt, ap);
+	va_end(ap);
+
+	exit(1);
+}
+
+static int
+evsnprintf(char *str, size_t size, const char *fmt, va_list ap)
+{
+	int ret;
+
+	ret = vsnprintf(str, size, fmt, ap);
+
+	if (ret < 0) {
+		warn("vsnprintf:");
+		return -1;
+	} else if ((size_t)ret >= size) {
+		warn("vsnprintf: Output truncated");
+		return -1;
+	}
+
+	return ret;
+}
+
+int
+esnprintf(char *str, size_t size, const char *fmt, ...)
+{
+	va_list ap;
+	int ret;
+
+	va_start(ap, fmt);
+	ret = evsnprintf(str, size, fmt, ap);
+	va_end(ap);
+
+	return ret;
+}
+
+const char *
+bprintf(const char *fmt, ...)
+{
+	va_list ap;
+	int ret;
+
+	va_start(ap, fmt);
+	ret = evsnprintf(buf, sizeof(buf), fmt, ap);
+	va_end(ap);
+
+	return (ret < 0) ? NULL : buf;
+}
+
+const char *
+fmt_human(uintmax_t num, int base)
+{
+	double scaled;
+	size_t i, prefixlen;
+	const char **prefix;
+	const char *prefix_1000[] = { "", "k", "M", "G", "T", "P", "E", "Z",
+	                              "Y" };
+	const char *prefix_1024[] = { "", "Ki", "Mi", "Gi", "Ti", "Pi", "Ei",
+	                              "Zi", "Yi" };
+
+	switch (base) {
+	case 1000:
+		prefix = prefix_1000;
+		prefixlen = LEN(prefix_1000);
+		break;
+	case 1024:
+		prefix = prefix_1024;
+		prefixlen = LEN(prefix_1024);
+		break;
+	default:
+		warn("fmt_human: Invalid base");
+		return NULL;
+	}
+
+	scaled = num;
+	for (i = 0; i < prefixlen && scaled >= base; i++) {
+		scaled /= base;
+	}
+
+	return bprintf("%.1f %s", scaled, prefix[i]);
+}
+
+int
+pscanf(const char *path, const char *fmt, ...)
+{
+	FILE *fp;
+	va_list ap;
+	int n;
+
+	if (!(fp = fopen(path, "r"))) {
+		warn("fopen '%s':", path);
+		return -1;
+	}
+	va_start(ap, fmt);
+	n = vfscanf(fp, fmt, ap);
+	va_end(ap);
+	fclose(fp);
+
+	return (n == EOF) ? -1 : n;
+}

util.h

@@ -0,0 +1,16 @@
+/* See LICENSE file for copyright and license details. */
+#include <stdint.h>
+
+extern char buf[1024];
+
+#define LEN(x) (sizeof (x) / sizeof *(x))
+
+extern char *argv0;
+
+void warn(const char *, ...);
+void die(const char *, ...);
+
+int esnprintf(char *str, size_t size, const char *fmt, ...);
+const char *bprintf(const char *fmt, ...);
+const char *fmt_human(uintmax_t num, int base);
+int pscanf(const char *path, const char *fmt, ...);