slstatus/slstatus.c

133 lines
2.5 KiB
C

/* 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 *);
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 &&
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;
}