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Date:: Sat May 19 16:14:49 2018 UTC
Message:: this commit = UTF8 input handling + keybindings - bugs
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1 /* mymenu -- simple dmenu alternative */
2 
3 /* Copyright (C) 2018  Omar Polo <omar.polo@europecom.net>
4  *
5  * This program is free software: you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation, either version 3 of the License, or
8  * (at your option) any later version.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
17  */
18 
19 #include <stdio.h>
20 #include <stdlib.h>
21 #include <string.h>    // strdup, strnlen, ...
22 #include <ctype.h>     // isalnum
23 #include <locale.h>    // setlocale
24 #include <unistd.h>
25 #include <sysexits.h>
26 #include <stdbool.h>
27 #include <limits.h>
28 #include <errno.h>
29 
30 #include <X11/Xlib.h>
31 #include <X11/Xutil.h> // XLookupString
32 #include <X11/Xresource.h>
33 #include <X11/Xcms.h>  // colors
34 #include <X11/keysym.h>
35 
36 #ifdef USE_XINERAMA
37 # include <X11/extensions/Xinerama.h>
38 #endif
39 
40 #define nil NULL
41 #define resname "MyMenu"
42 #define resclass "mymenu"
43 
44 #define MIN(X, Y) (((X) < (Y)) ? (X) : (Y))
45 #define MAX(a, b) ((a) > (b) ? (a) : (b))
46 #define OVERLAP(a,b,c,d) (((a)==(c) && (b)==(d)) || MIN((a)+(b), (c)+(d)) - MAX((a), (c)) > 0)
47 #define INTERSECT(x,y,w,h,x1,y1,w1,h1) (OVERLAP((x),(w),(x1),(w1)) && OVERLAP((y),(h),(y1),(h1)))
48 
49 #define update_completions(cs, text, lines) {   \
50     compl_delete(cs);                           \
51     cs = filter(text, lines);                   \
52   }
53 
54 // TODO: dynamic?
55 #define MAX_ITEMS 256
56 
57 #define TODO(s) {                               \
58     fprintf(stderr, "TODO! " s "\n");           \
59   }
60 
61 #define cannot_allocate_memory {                        \
62     fprintf(stderr, "Could not allocate memory\n");     \
63     exit(EX_UNAVAILABLE);                               \
64   }
65 
66 #define check_allocation(a) {     \
67     if (a == nil)                 \
68       cannot_allocate_memory;     \
69   }
70 
71 enum state {LOOPING, OK, ERR};
72 
73 struct rendering {
74   Display *d;
75   Window w;
76   GC prompt;
77   GC prompt_bg;
78   GC completion;
79   GC completion_bg;
80   GC completion_highlighted;
81   GC completion_highlighted_bg;
82   int width;
83   int height;
84   XFontSet *font;
85 };
86 
87 struct completions {
88   char *completion;
89   bool selected;
90   struct completions *next;
91 };
92 
93 struct completions *compl_new() {
94   struct completions *c = malloc(sizeof(struct completions));
95 
96   if (c == nil)
97     return c;
98 
99   c->completion = nil;
100   c->selected = false;
101   c->next = nil;
102   return c;
103 }
104 
105 void compl_delete(struct completions *c) {
106   free(c);
107 }
108 
109 struct completions *compl_select_next(struct completions *c, bool n) {
110   if (c == nil)
111     return nil;
112   if (n) {
113     c->selected = true;
114     return c;
115   }
116 
117   struct completions *orig = c;
118   while (c != nil) {
119     if (c->selected) {
120       c->selected = false;
121       if (c->next != nil) {
122         // the current one is selected and the next one exists
123         c->next->selected = true;
124         return c->next;
125       } else {
126         // the current one is selected and the next one is nill,
127         // select the first one
128         orig->selected = true;
129         return orig;
130       }
131     }
132     c = c->next;
133   }
134   return nil;
135 }
136 
137 struct completions *compl_select_prev(struct completions *c, bool n) {
138   if (c == nil)
139     return nil;
140 
141   struct completions *cc = c;
142 
143   if (n) // select the last one
144     while (cc != nil) {
145       if (cc->next == nil) {
146         cc->selected = true;
147         return cc;
148       }
149       cc = cc->next;
150     }
151   else // select the previous one
152     while (cc != nil) {
153       if (cc->next != nil && cc->next->selected) {
154         cc->next->selected = false;
155         cc->selected = true;
156         return cc;
157       }
158       cc = cc->next;
159     }
160   
161   return nil;
162 }
163 
164 struct completions *filter(char *text, char **lines) {
165   int i = 0;
166   struct completions *root = compl_new();
167   struct completions *c = root;
168 
169   for (;;) {
170     char *l = lines[i];
171     if (l == nil)
172       break;
173 
174     if (strstr(l, text) != nil) {
175       c->next = compl_new();
176       c = c->next;
177       c->completion = l;
178     }
179 
180     ++i;
181   }
182 
183   struct completions *r = root->next;
184   compl_delete(root);
185   return r;
186 }
187 
188 // push the character c at the end of the string pointed by p
189 int pushc(char **p, int maxlen, char c) {
190   int len = strnlen(*p, maxlen);
191 
192   if (!(len < maxlen -2)) {
193     maxlen += maxlen >> 1;
194     char *newptr = realloc(*p, maxlen);
195     if (newptr == nil) { // bad!
196       return -1;
197     }
198     *p = newptr;
199   }
200 
201   (*p)[len] = c;
202   (*p)[len+1] = '\0';
203   return maxlen;
204 }
205 
206 int utf8strnlen(char *s, int maxlen) {
207   int len = 0;
208   while (*s && maxlen > 0) {
209     len += (*s++ & 0xc0) != 0x80;
210     maxlen--;
211   }
212   return len;
213 }
214 
215 // remove the last *glyph* from the *utf8* string!
216 // this is different from just setting the last byte to 0 (in some
217 // cases ofc). The actual implementation is quite inefficient because
218 // it remove the last char until the number of glyphs doesn't change
219 void popc(char *p, int maxlen) {
220   int len = strnlen(p, maxlen);
221 
222   if (len == 0)
223     return;
224 
225   int ulen = utf8strnlen(p, maxlen);
226   while (len > 0 && utf8strnlen(p, maxlen) == ulen) {
227     len--;
228     p[len] = 0;
229   }
230 }
231 
232 // read an arbitrary long line from stdin and return a pointer to it
233 // TODO: resize the allocated memory to exactly fit the string once
234 // read?
235 char *readline(bool *eof) {
236   int maxlen = 8;
237   char *str = calloc(maxlen, sizeof(char));
238   if (str == nil) {
239     fprintf(stderr, "Cannot allocate memory!\n");
240     exit(EX_UNAVAILABLE);
241   }
242 
243   int c;
244   while((c = getchar()) != EOF) {
245     if (c == '\n')
246       return str;
247     else
248       maxlen = pushc(&str, maxlen, c);
249 
250     if (maxlen == -1) {
251       fprintf(stderr, "Cannot allocate memory!\n");
252       exit(EX_UNAVAILABLE);
253     }
254   }
255   *eof = true;
256   return str;
257 }
258 
259 int readlines (char **lines) {
260   bool finished = false;
261   int n = 0;
262   while (n < MAX_ITEMS) {
263     lines[n] = readline(&finished);
264 
265     if (strlen(lines[n]) == 0 || lines[n][0] == '\n')
266       --n; // forget about this line
267 
268     if (finished)
269       break;
270 
271     ++n;
272   }
273   /* for (n = 0; n < MAX_ITEMS -1; ++n) { */
274   /*   lines[n] = readline(&finished); */
275   /*   if (finished) */
276   /*     break; */
277   /* } */
278   n++;
279   lines[n] = nil;
280   return n;
281 }
282 
283 // |------------------|----------------------------------------------|
284 // | 20 char text     | completion | completion | completion | compl |
285 // |------------------|----------------------------------------------|
286 void draw(struct rendering *r, char *text, struct completions *cs) {
287   // TODO: make these dynamic?
288   int prompt_width = 20; // char
289   int padding = 10;
290   /* int start_at = XTextWidth(r->font, " ", 1) * prompt_width + padding; */
291 
292   XRectangle rect;
293   int start_at = XmbTextExtents(*r->font, " ", 1, nil, &rect);
294   start_at = start_at * prompt_width + padding;
295 
296   int texty = (rect.height + r->height) >>1;
297 
298   XFillRectangle(r->d, r->w, r->prompt_bg, 0, 0, start_at, r->height);
299 
300   int text_len = strlen(text);
301   if (text_len > prompt_width)
302     text = text + (text_len - prompt_width);
303   /* XDrawString(r->d, r->w, r->prompt, padding, texty, text, MIN(text_len, prompt_width)); */
304   Xutf8DrawString(r->d, r->w, *r->font, r->prompt, padding, texty, text, MIN(text_len, prompt_width));
305 
306   XFillRectangle(r->d, r->w, r->completion_bg, start_at, 0, r->width, r->height);
307 
308   while (cs != nil) {
309     GC g = cs->selected ? r->completion_highlighted    : r->completion;
310     GC h = cs->selected ? r->completion_highlighted_bg : r->completion_bg;
311 
312     int len = strlen(cs->completion);
313     /* int text_width = XTextWidth(r->font, cs->completion, len); */
314     int text_width = XmbTextExtents(*r->font, cs->completion, len, nil, nil);
315 
316     XFillRectangle(r->d, r->w, h, start_at, 0, text_width + padding*2, r->height);
317 
318     /*  XDrawString(r->d, r->w,           g, start_at + padding, texty, cs->completion, len); */
319     Xutf8DrawString(r->d, r->w, *r->font, g, start_at + padding, texty, cs->completion, len);
320 
321     start_at += text_width + padding * 2;
322 
323     cs = cs->next;
324   }
325 
326   XFlush(r->d);
327 }
328 
329 /* Set some WM stuff */
330 void set_win_atoms_hints(Display *d, Window w, int width, int height) {
331   Atom type;
332   type = XInternAtom(d, "_NET_WM_WINDOW_TYPE_DOCK", false);
333   XChangeProperty(
334                   d,
335                   w,
336                   XInternAtom(d, "_NET_WM_WINDOW_TYPE", false),
337                   XInternAtom(d, "ATOM", false),
338                   32,
339                   PropModeReplace,
340                   (unsigned char *)&type,
341                   1
342                   );
343 
344   /* some window managers honor this properties */
345   type = XInternAtom(d, "_NET_WM_STATE_ABOVE", false);
346   XChangeProperty(d,
347                   w,
348                   XInternAtom(d, "_NET_WM_STATE", false),
349                   XInternAtom(d, "ATOM", false),
350                   32,
351                   PropModeReplace,
352                   (unsigned char *)&type,
353                   1
354                   );
355 
356   type = XInternAtom(d, "_NET_WM_STATE_FOCUSED", false);
357   XChangeProperty(d,
358                   w,
359                   XInternAtom(d, "_NET_WM_STATE", false),
360                   XInternAtom(d, "ATOM", false),
361                   32,
362                   PropModeAppend,
363                   (unsigned char *)&type,
364                   1
365                   );
366 
367   // setting window hints
368   XClassHint *class_hint = XAllocClassHint();
369   if (class_hint == nil) {
370     fprintf(stderr, "Could not allocate memory for class hint\n");
371     exit(EX_UNAVAILABLE);
372   }
373   class_hint->res_name = "mymenu";
374   class_hint->res_class = "mymenu";
375   XSetClassHint(d, w, class_hint);
376   XFree(class_hint);
377 
378   XSizeHints *size_hint = XAllocSizeHints();
379   if (size_hint == nil) {
380     fprintf(stderr, "Could not allocate memory for size hint\n");
381     exit(EX_UNAVAILABLE);
382   }
383   size_hint->min_width = width;
384   size_hint->base_width = width;
385   size_hint->min_height = height;
386   size_hint->base_height = height;
387 
388   XFlush(d);
389 }
390 
391 void get_wh(Display *d, Window *w, int *width, int *height) {
392   XWindowAttributes win_attr;
393   XGetWindowAttributes(d, *w, &win_attr);
394   *height = win_attr.height;
395   *width = win_attr.width;
396 }
397 
398 // I know this may seem a little hackish BUT is the only way I managed
399 // to actually grab that goddam keyboard. Only one call to
400 // XGrabKeyboard does not always end up with the keyboard grabbed!
401 int take_keyboard(Display *d, Window w) {
402   int i;
403   for (i = 0; i < 100; i++) {
404     if (XGrabKeyboard(d, w, True, GrabModeAsync, GrabModeAsync, CurrentTime) == GrabSuccess)
405       return 1;
406     usleep(1000);
407   }
408   return 0;
409 }
410 
411 void release_keyboard(Display *d) {
412   XUngrabKeyboard(d, CurrentTime);
413 }
414 
415 int parse_integer(const char *str, int default_value, int max) {
416   int len = strlen(str);
417   if (len > 0 && str[len-1] == '%') {
418     char *cpy = strdup(str);
419     check_allocation(cpy);
420     cpy[len-1] = '\0';
421     int val = parse_integer(cpy, default_value, max);
422     free(cpy);
423     return val * max / 100;
424   }
425 
426   errno = 0;
427   char *ep;
428   long lval = strtol(str, &ep, 10);
429   if (str[0] == '\0' || *ep != '\0') { // NaN
430     fprintf(stderr, "'%s' is not a valid number! Using %d as default.\n", str, default_value);
431     return default_value;
432   }
433   if ((errno == ERANGE && (lval == LONG_MAX || lval == LONG_MIN)) ||
434       (lval > INT_MAX || lval < INT_MIN)) {
435     fprintf(stderr, "%s out of range! Using %d as default.\n", str, default_value);
436     return default_value;
437   }
438   return lval;
439 }
440 
441 int parse_int_with_middle(const char *str, int default_value, int max, int self) {
442   if (!strcmp(str, "middle")) {
443     return (max - self)/2;
444   }
445   return parse_integer(str, default_value, max);
446 }
447 
448 int main() {
449   char *lines[MAX_ITEMS] = {0};
450   readlines(lines);
451 
452   setlocale(LC_ALL, getenv("LANG"));
453 
454   enum state status = LOOPING;
455 
456   // where the monitor start (used only with xinerama)
457   int offset_x = 0;
458   int offset_y = 0;
459 
460   // width and height of the window
461   int width = 400;
462   int height = 20;
463 
464   // position on the screen
465   int x = 0;
466   int y = 0;
467 
468   char *fontname = strdup("fixed");
469   check_allocation(fontname);
470 
471   int textlen = 10;
472   char *text = malloc(textlen * sizeof(char));
473   check_allocation(text);
474 
475   struct completions *cs = filter(text, lines);
476   bool nothing_selected = true;
477 
478   // start talking to xorg
479   Display *d = XOpenDisplay(nil);
480   if (d == nil) {
481     fprintf(stderr, "Could not open display!\n");
482     return EX_UNAVAILABLE;
483   }
484 
485   // get display size
486   // XXX: is getting the default root window dimension correct?
487   XWindowAttributes xwa;
488   XGetWindowAttributes(d, DefaultRootWindow(d), &xwa);
489   int d_width = xwa.width;
490   int d_height = xwa.height;
491 
492 #ifdef USE_XINERAMA
493   // TODO: this bit still needs to be improved
494   if (XineramaIsActive(d)) {
495     int monitors;
496     XineramaScreenInfo *info = XineramaQueryScreens(d, &monitors);
497     if (info)
498       for (int i = 0; i < monitors; ++i) {
499         if (INTERSECT(x, y, 1, 1, info[i].x_org, info[i].y_org, info[i].width, info[i].height)) {
500           offset_x = info[x].x_org;
501           offset_y = info[y].y_org;
502           d_width = info[i].width;
503           d_height = info[i].height;
504         }
505       }
506     XFree(info);
507   }
508 #endif
509 
510   /* fprintf(stderr, "offset_x:\t%d\n" */
511   /*                 "offset_y:\t%d\n" */
512   /*                 "d_width:\t%d\n" */
513   /*                 "d_height:\t%d\n" */
514   /*         , offset_x, offset_y, d_width, d_height); */
515 
516   Colormap cmap = DefaultColormap(d, DefaultScreen(d));
517   XColor p_fg, p_bg,
518     compl_fg, compl_bg,
519     compl_highlighted_fg, compl_highlighted_bg;
520 
521   // read resource
522   XrmInitialize();
523   char *xrm = XResourceManagerString(d);
524   XrmDatabase xdb = nil;
525   if (xrm != nil) {
526     xdb = XrmGetStringDatabase(xrm);
527     XrmValue value;
528     char *datatype[20];
529 
530     if (XrmGetResource(xdb, "MyMenu.font", "*", datatype, &value) == true) {
531       fontname = strdup(value.addr);
532       check_allocation(fontname);
533     }
534     else
535       fprintf(stderr, "no font defined, using %s\n", fontname);
536 
537     if (XrmGetResource(xdb, "MyMenu.width", "*", datatype, &value) == true)
538       width = parse_integer(value.addr, width, d_width);
539     else
540       fprintf(stderr, "no width defined, using %d\n", width);
541 
542     if (XrmGetResource(xdb, "MyMenu.height", "*", datatype, &value) == true)
543       height = parse_integer(value.addr, height, d_height);
544     else
545       fprintf(stderr, "no height defined, using %d\n", height);
546 
547     if (XrmGetResource(xdb, "MyMenu.x", "*", datatype, &value) == true)
548       x = parse_int_with_middle(value.addr, x, d_width, width);
549     else
550       fprintf(stderr, "no x defined, using %d\n", width);
551 
552     if (XrmGetResource(xdb, "MyMenu.y", "*", datatype, &value) == true)
553       y = parse_int_with_middle(value.addr, y, d_height, height);
554     else
555       fprintf(stderr, "no y defined, using %d\n", height);
556 
557     XColor tmp;
558     // TODO: tmp needs to be free'd after every allocation?
559 
560     // prompt
561     if (XrmGetResource(xdb, "MyMenu.prompt.foreground", "*", datatype, &value) == true)
562       XAllocNamedColor(d, cmap, value.addr, &p_fg, &tmp);
563     else
564       XAllocNamedColor(d, cmap, "white", &p_fg, &tmp);
565 
566     if (XrmGetResource(xdb, "MyMenu.prompt.background", "*", datatype, &value) == true)
567       XAllocNamedColor(d, cmap, value.addr, &p_bg, &tmp);
568     else
569       XAllocNamedColor(d, cmap, "black", &p_bg, &tmp);
570 
571     // completion
572     if (XrmGetResource(xdb, "MyMenu.completion.foreground", "*", datatype, &value) == true)
573       XAllocNamedColor(d, cmap, value.addr, &compl_fg, &tmp);
574     else
575       XAllocNamedColor(d, cmap, "white", &compl_fg, &tmp);
576 
577     if (XrmGetResource(xdb, "MyMenu.completion.background", "*", datatype, &value) == true)
578       XAllocNamedColor(d, cmap, value.addr, &compl_bg, &tmp);
579     else
580       XAllocNamedColor(d, cmap, "black", &compl_bg, &tmp);
581 
582     // completion highlighted
583     if (XrmGetResource(xdb, "MyMenu.completion_highlighted.foreground", "*", datatype, &value) == true)
584       XAllocNamedColor(d, cmap, value.addr, &compl_highlighted_fg, &tmp);
585     else
586       XAllocNamedColor(d, cmap, "black", &compl_highlighted_fg, &tmp);
587 
588     if (XrmGetResource(xdb, "MyMenu.completion_highlighted.background", "*", datatype, &value) == true)
589       XAllocNamedColor(d, cmap, value.addr, &compl_highlighted_bg, &tmp);
590     else
591       XAllocNamedColor(d, cmap, "white", &compl_highlighted_bg, &tmp);
592   } else {
593     XColor tmp;
594     XAllocNamedColor(d, cmap, "white", &p_fg, &tmp);
595     XAllocNamedColor(d, cmap, "black", &p_bg, &tmp);
596     XAllocNamedColor(d, cmap, "white", &compl_fg, &tmp);
597     XAllocNamedColor(d, cmap, "black", &compl_bg, &tmp);
598     XAllocNamedColor(d, cmap, "black", &compl_highlighted_fg, &tmp);
599     XAllocNamedColor(d, cmap, "white", &compl_highlighted_bg, &tmp);
600   }
601 
602   // load the font
603   /* XFontStruct *font = XLoadQueryFont(d, fontname); */
604   /* if (font == nil) { */
605   /*   fprintf(stderr, "Unable to load %s font\n", fontname); */
606   /*   font = XLoadQueryFont(d, "fixed"); */
607   /* } */
608   // load the font
609   char **missing_charset_list;
610   int missing_charset_count;
611   XFontSet font = XCreateFontSet(d, fontname, &missing_charset_list, &missing_charset_count, nil);
612   if (font == nil) {
613     fprintf(stderr, "Unable to load the font(s) %s\n", fontname);
614     return EX_UNAVAILABLE;
615   }
616 
617   // create the window
618   XSetWindowAttributes attr;
619 
620   Window w = XCreateWindow(d,                                   // display
621                            DefaultRootWindow(d),                // parent
622                            x + offset_x, y + offset_y,          // x y
623                            width, height,                       // w h
624                            0,                                   // border width
625                            DefaultDepth(d, DefaultScreen(d)),   // depth
626                            InputOutput,                         // class
627                            DefaultVisual(d, DefaultScreen(d)),  // visual
628                            0,                                   // value mask
629                            &attr);
630 
631   set_win_atoms_hints(d, w, width, height);
632 
633   // we want some events
634   XSelectInput(d, w, StructureNotifyMask | KeyPressMask | KeyReleaseMask | KeymapStateMask);
635 
636   // make the window appear on the screen
637   XMapWindow(d, w);
638 
639   // wait for the MapNotify event (i.e. the event "window rendered")
640   for (;;) {
641     XEvent e;
642     XNextEvent(d, &e);
643     if (e.type == MapNotify)
644       break;
645   }
646 
647   // get the *real* width & height after the window was rendered
648   get_wh(d, &w, &width, &height);
649 
650   // grab keyboard
651   take_keyboard(d, w);
652 
653   // Create some graphics contexts
654   XGCValues values;
655   /* values.font = font->fid; */
656 
657   struct rendering r = {
658     .d                          = d,
659     .w                          = w,
660     .prompt                     = XCreateGC(d, w, 0, &values),
661     .prompt_bg                  = XCreateGC(d, w, 0, &values),
662     .completion                 = XCreateGC(d, w, 0, &values),
663     .completion_bg              = XCreateGC(d, w, 0, &values),
664     .completion_highlighted     = XCreateGC(d, w, 0, &values),
665     .completion_highlighted_bg  = XCreateGC(d, w, 0, &values),
666     /* .prompt                     = XCreateGC(d, w, GCFont, &values), */
667     /* .prompt_bg                  = XCreateGC(d, w, GCFont, &values), */
668     /* .completion                 = XCreateGC(d, w, GCFont, &values), */
669     /* .completion_bg              = XCreateGC(d, w, GCFont, &values), */
670     /* .completion_highlighted     = XCreateGC(d, w, GCFont, &values), */
671     /* .completion_highlighted_bg  = XCreateGC(d, w, GCFont, &values), */
672     .width                      = width,
673     .height                     = height,
674     .font                       = &font
675   };
676 
677   // load the colors in our GCs
678   XSetForeground(d, r.prompt, p_fg.pixel);
679   XSetForeground(d, r.prompt_bg, p_bg.pixel);
680   XSetForeground(d, r.completion, compl_fg.pixel);
681   XSetForeground(d, r.completion_bg, compl_bg.pixel);
682   XSetForeground(d, r.completion_highlighted, compl_highlighted_fg.pixel);
683   XSetForeground(d, r.completion_highlighted_bg, compl_highlighted_bg.pixel);
684 
685   // open the X input method
686   XIM xim = XOpenIM(d, xdb, resname, resclass);
687   check_allocation(xim);
688 
689   XIMStyles *xis = nil;
690   if (XGetIMValues(xim, XNQueryInputStyle, &xis, NULL) || !xis) {
691     fprintf(stderr, "Input Styles could not be retrieved\n");
692     return EX_UNAVAILABLE;
693   }
694 
695   XIMStyle bestMatchStyle = 0;
696   for (int i = 0; i < xis->count_styles; ++i) {
697     XIMStyle ts = xis->supported_styles[i];
698     if (ts == (XIMPreeditNothing | XIMStatusNothing)) {
699       bestMatchStyle = ts;
700       break;
701     }
702   }
703   XFree(xis);
704 
705   if (!bestMatchStyle) {
706     fprintf(stderr, "No matching input style could be determined\n");
707   }
708 
709   XIC xic = XCreateIC(xim, XNInputStyle, bestMatchStyle, XNClientWindow, w, XNFocusWindow, w, NULL);
710   check_allocation(xic);
711 
712   // draw the window for the first time
713   draw(&r, text, cs);
714 
715   // main loop
716   while (status == LOOPING) {
717     XEvent e;
718     XNextEvent(d, &e);
719 
720     if (XFilterEvent(&e, w))
721       continue;
722 
723     switch (e.type) {
724     case KeymapNotify:
725       XRefreshKeyboardMapping(&e.xmapping);
726       break;
727 
728     case KeyRelease: break; // ignore this
729 
730     case KeyPress: {
731       XKeyPressedEvent *ev = (XKeyPressedEvent*)&e;
732 
733       if (ev->keycode == XKeysymToKeycode(d, XK_Tab)) {
734         bool shift = (ev->state & ShiftMask);
735         struct completions *n = shift ? compl_select_prev(cs, nothing_selected)
736                                       : compl_select_next(cs, nothing_selected);
737         if (n != nil) {
738           nothing_selected = false;
739           free(text);
740           text = strdup(n->completion);
741           if (text == nil) {
742             fprintf(stderr, "Memory allocation error!\n");
743             status = ERR;
744             break;
745           }
746           textlen = strlen(text);
747         }
748         draw(&r, text, cs);
749         break;
750       }
751 
752       if (ev->keycode == XKeysymToKeycode(d, XK_BackSpace)) {
753         nothing_selected = true;
754         popc(text, textlen);
755         update_completions(cs, text, lines);
756         draw(&r, text, cs);
757         break;
758       }
759 
760       if (ev->keycode == XKeysymToKeycode(d, XK_Return)) {
761         status = OK;
762         break;
763       }
764 
765       if (ev->keycode == XKeysymToKeycode(d, XK_Escape)) {
766         status = ERR;
767         break;
768       }
769 
770       // try to read what the user pressed
771       int symbol = 0;
772       Status s = 0;
773       Xutf8LookupString(xic, ev, (char*)&symbol, 4, 0, &s);
774 
775       if (s == XBufferOverflow) {
776         // should not happen since there are no utf-8 characters
777         // larger than 24bits, but is something to be aware of when
778         // used to directly write to a string buffer
779         fprintf(stderr, "Buffer overflow when trying to create keyboard symbol map.\n");
780         break;
781       }
782       char *str = (char*)&symbol;
783 
784       if (ev->state & ControlMask) {
785         // check for some key bindings
786         if (!strcmp(str, "")) { // C-u
787           nothing_selected = true;
788           for (int i = 0; i < textlen; ++i)
789             text[i] = 0;
790           update_completions(cs, text, lines);
791         }
792         if (!strcmp(str, "")) { // C-h
793           nothing_selected = true;
794           popc(text, textlen);
795           update_completions(cs, text, lines);
796         }
797         if (!strcmp(str, "")) { // C-w
798           nothing_selected = true;
799 
800           // `textlen` is the length of the allocated string, not the
801           // length of the ACTUAL string
802           int p = strlen(text) - 1;
803           if (p >= 0) { // delete the current char
804             text[p] = 0;
805             p--;
806           }
807           while (p >= 0 && isalnum(text[p])) {
808             text[p] = 0;
809             p--;
810           }
811           // erase also trailing white space
812           while (p >= 0 && isspace(text[p])) {
813             text[p] = 0;
814             p--;
815           }
816           update_completions(cs, text, lines);
817         }
818         if (!strcmp(str, "\r")) { // C-m
819           status = OK;
820         }
821         draw(&r, text, cs);
822         break;
823       }
824 
825       int str_len = strlen(str);
826       for (int i = 0; i < str_len; ++i) {
827         textlen = pushc(&text, textlen, str[i]);
828         if (textlen == -1) {
829           fprintf(stderr, "Memory allocation error\n");
830           status = ERR;
831           break;
832         }
833         nothing_selected = true;
834         update_completions(cs, text, lines);
835       }
836 
837     }
838       draw(&r, text, cs);
839       break;
840 
841     default:
842       fprintf(stderr, "Unknown event %d\n", e.type);
843     }
844   }
845 
846   release_keyboard(d);
847 
848   if (status == OK)
849     printf("%s\n", text);
850 
851   free(fontname);
852   free(text);
853   compl_delete(cs);
854 
855   /* XDestroyWindow(d, w); */
856   XCloseDisplay(d);
857 
858   return status == OK ? 0 : 1;
859 }