dwm-status

  1/* See LICENSE for license details. */
  2
  3#include <assert.h>
  4#include <err.h>
  5#include <stdarg.h>
  6#include <stdio.h>
  7#include <stdlib.h>
  8#include <string.h>
  9#include <time.h>
 10#include <limits.h>
 11#include <unistd.h>
 12
 13#include <sys/types.h>
 14#include <X11/Xlib.h>
 15#include <tinyalsa/asoundlib.h>
 16
 17static size_t alsavol(char*, size_t);
 18static size_t batcap(char*, size_t);
 19static size_t loadavg(char*, size_t);
 20static size_t curtime(char*, size_t);
 21static size_t separator(char*, size_t);
 22
 23#include "config.h"
 24
 25enum {
 26	STATUSSZ = 128,
 27};
 28
 29static char ststr[STATUSSZ];
 30
 31static int
 32xsnprintf(char *restrict s, size_t n, const char *restrict fmt, ...)
 33{
 34	int ret;
 35	va_list ap;
 36
 37	va_start(ap, fmt);
 38	ret = vsnprintf(s, n, fmt, ap);
 39	va_end(ap);
 40
 41	if (ret < 0) {
 42		err(EXIT_FAILURE, "snprintf failed");
 43	} else if ((size_t)ret >= n) {
 44		warnx("snprintf: insufficient buffer size");
 45		ret = n;
 46	}
 47
 48	return ret;
 49}
 50
 51static double
 52readnum(char *bfp, char *fn)
 53{
 54	int ret;
 55	FILE *file;
 56	size_t rclen;
 57	char buf[16], fp[PATH_MAX + 1], *rc;
 58
 59	rc = NULL;
 60	if ((ret = snprintf(fp, sizeof(fp), "%s/%s", bfp, fn)) < 0)
 61		errx(EXIT_FAILURE, "snprintf failed");
 62	else if ((size_t)ret >= sizeof(fp))
 63		errx(EXIT_FAILURE, "buffer 'fp' is too short");
 64
 65	if (!(file = fopen(fp, "r")))
 66		err(EXIT_FAILURE, "couldn't open '%s'", fp);
 67
 68	if (!(rc = fgets(buf, 16, file))) {
 69		fclose(file);
 70		errx(EXIT_FAILURE, "'%s' seems to be empty", fp);
 71	}
 72
 73	rclen = strlen(buf);
 74	if (rc[rclen - 1] == '\n')
 75		rc[rclen - 1] = '\0';
 76
 77	fclose(file);
 78	return atof(rc);
 79}
 80
 81static size_t
 82actlstr(char *buf, size_t n, char *ch, struct mixer *mx) {
 83	size_t ret;
 84	char *status;
 85	struct mixer_ctl *ctl;
 86
 87	if (!(ctl = mixer_get_ctl_by_name(mx, ch))) {
 88		mixer_close(mx);
 89		errx(EXIT_FAILURE, "couldn't find mixer ctl '%s'\n", ch);
 90	}
 91
 92	switch (mixer_ctl_get_type(ctl)) {
 93	case MIXER_CTL_TYPE_INT:
 94		return xsnprintf(buf, n, "%d%%",
 95			mixer_ctl_get_percent(ctl, 0));
 96	case MIXER_CTL_TYPE_BOOL:
 97		status = mixer_ctl_get_value(ctl, 0) ? "On" : "Off";
 98		ret = stpncpy(buf, status, n) - buf;
 99		break;
100	default:
101		mixer_close(mx);
102		errx(EXIT_FAILURE, "unsupported ctl type '%s'\n",
103			mixer_ctl_get_type_string(ctl));
104	};
105
106	return ret;
107}
108
109static size_t
110batcap(char *dest, size_t n)
111{
112	int cap;
113
114	cap = readnum((char*)sysbat, "capacity");
115	return xsnprintf(dest, n, "%d%%", cap);
116}
117
118static size_t
119alsavol(char *dest, size_t n)
120{
121	size_t ret;
122	struct mixer *mx;
123
124	if (!(mx = mixer_open(sndcrd)))
125		errx(EXIT_FAILURE, "couldn't open mixer for card %d\n", sndcrd);
126
127	ret = actlstr(dest, n, (char*)swtchname, mx);
128	if (strcmp(dest, "Off"))
129		ret = actlstr(dest, n, (char*)volumname, mx);
130
131	mixer_close(mx);
132	return ret;
133}
134
135static size_t
136loadavg(char* dest, size_t n)
137{
138	double avgs[3];
139
140	if (!getloadavg(avgs, 3))
141		err(EXIT_FAILURE, "getloadavg failed");
142
143	return xsnprintf(dest, n, "%.2f %.2f %.2f",
144		avgs[0], avgs[1], avgs[2]);
145}
146
147static size_t
148curtime(char *dest, size_t n)
149{
150	time_t tim;
151	struct tm *timtm;
152
153	if ((tim = time(NULL)) == (time_t)-1)
154		err(EXIT_FAILURE, "time failed");
155
156	if (!(timtm = localtime(&tim)))
157		err(EXIT_FAILURE, "localtime failed");
158
159	return strftime(dest, n, timefmt, timtm);
160}
161
162static size_t
163separator(char *dest, size_t n)
164{
165	return stpncpy(dest, statsep, n) - dest;
166}
167
168int
169main(void)
170{
171	Display *dpy;
172	Window root;
173	size_t i, x, fns, max;
174
175	if (!(dpy = XOpenDisplay(NULL)))
176		errx(EXIT_FAILURE, "couldn't open display '%s'", XDisplayName(NULL));
177	root = DefaultRootWindow(dpy);
178
179	max = STATUSSZ - 1;
180	fns = sizeof(sfuncs) / sizeof(sfuncs[0]);
181
182	for (;;) {
183		for (i = 0, x = 0; i < fns && x < max; i++) {
184			assert(max >= x);
185			x += (*sfuncs[i])(&(ststr[x]), max - x);
186		}
187
188		assert(x < STATUSSZ);
189		ststr[x] = '\0';
190
191		XStoreName(dpy, root, ststr);
192		XSync(dpy, False);
193		sleep(delay);
194	}
195
196	XCloseDisplay(dpy);
197	return EXIT_SUCCESS;
198}