slstatus

status monitor
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keyboard_indicators.c (1226B)


      1 /* See LICENSE file for copyright and license details. */
      2 #include <ctype.h>
      3 #include <stdio.h>
      4 #include <string.h>
      5 #include <X11/Xlib.h>
      6 
      7 #include "../util.h"
      8 
      9 /*
     10  * fmt consists of uppercase or lowercase 'c' for caps lock and/or 'n' for num
     11  * lock, each optionally followed by '?', in the order of indicators desired.
     12  * If followed by '?', the letter with case preserved is included in the output
     13  * if the corresponding indicator is on.  Otherwise, the letter is always
     14  * included, lowercase when off and uppercase when on.
     15  */
     16 const char *
     17 keyboard_indicators(const char *fmt)
     18 {
     19 	Display *dpy;
     20 	XKeyboardState state;
     21 	size_t fmtlen, i, n;
     22 	int togglecase, isset;
     23 	char key;
     24 
     25 	if (!(dpy = XOpenDisplay(NULL))) {
     26 		warn("XOpenDisplay: Failed to open display");
     27 		return NULL;
     28 	}
     29 	XGetKeyboardControl(dpy, &state);
     30 	XCloseDisplay(dpy);
     31 
     32 	fmtlen = strnlen(fmt, 4);
     33 	for (i = n = 0; i < fmtlen; i++) {
     34 		key = tolower(fmt[i]);
     35 		if (key != 'c' && key != 'n') {
     36 			continue;
     37 		}
     38 		togglecase = (i + 1 >= fmtlen || fmt[i + 1] != '?');
     39 		isset = (state.led_mask & (1 << (key == 'n')));
     40 		if (togglecase) {
     41 			buf[n++] = isset ? toupper(key) : key;
     42 		} else if (isset) {
     43 			buf[n++] = fmt[i];
     44 		}
     45 	}
     46 	buf[n] = 0;
     47 	return buf;
     48 }