op public repos

Blob

Date:: Sat May 19 20:52:11 2018 UTC
Message:: new layout: vertical
Actions:: History | Blame | Raw File
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   bool horizontal_layout;
86 };
87 
88 struct completions {
89   char *completion;
90   bool selected;
91   struct completions *next;
92 };
93 
94 struct completions *compl_new() {
95   struct completions *c = malloc(sizeof(struct completions));
96 
97   if (c == nil)
98     return c;
99 
100   c->completion = nil;
101   c->selected = false;
102   c->next = nil;
103   return c;
104 }
105 
106 void compl_delete(struct completions *c) {
107   free(c);
108 }
109 
110 struct completions *compl_select_next(struct completions *c, bool n) {
111   if (c == nil)
112     return nil;
113   if (n) {
114     c->selected = true;
115     return c;
116   }
117 
118   struct completions *orig = c;
119   while (c != nil) {
120     if (c->selected) {
121       c->selected = false;
122       if (c->next != nil) {
123         // the current one is selected and the next one exists
124         c->next->selected = true;
125         return c->next;
126       } else {
127         // the current one is selected and the next one is nill,
128         // select the first one
129         orig->selected = true;
130         return orig;
131       }
132     }
133     c = c->next;
134   }
135   return nil;
136 }
137 
138 struct completions *compl_select_prev(struct completions *c, bool n) {
139   if (c == nil)
140     return nil;
141 
142   struct completions *cc = c;
143 
144   if (n) // select the last one
145     while (cc != nil) {
146       if (cc->next == nil) {
147         cc->selected = true;
148         return cc;
149       }
150       cc = cc->next;
151     }
152   else // select the previous one
153     while (cc != nil) {
154       if (cc->next != nil && cc->next->selected) {
155         cc->next->selected = false;
156         cc->selected = true;
157         return cc;
158       }
159       cc = cc->next;
160     }
161   
162   return nil;
163 }
164 
165 struct completions *filter(char *text, char **lines) {
166   int i = 0;
167   struct completions *root = compl_new();
168   struct completions *c = root;
169 
170   for (;;) {
171     char *l = lines[i];
172     if (l == nil)
173       break;
174 
175     if (strstr(l, text) != nil) {
176       c->next = compl_new();
177       c = c->next;
178       c->completion = l;
179     }
180 
181     ++i;
182   }
183 
184   struct completions *r = root->next;
185   compl_delete(root);
186   return r;
187 }
188 
189 // push the character c at the end of the string pointed by p
190 int pushc(char **p, int maxlen, char c) {
191   int len = strnlen(*p, maxlen);
192 
193   if (!(len < maxlen -2)) {
194     maxlen += maxlen >> 1;
195     char *newptr = realloc(*p, maxlen);
196     if (newptr == nil) { // bad!
197       return -1;
198     }
199     *p = newptr;
200   }
201 
202   (*p)[len] = c;
203   (*p)[len+1] = '\0';
204   return maxlen;
205 }
206 
207 int utf8strnlen(char *s, int maxlen) {
208   int len = 0;
209   while (*s && maxlen > 0) {
210     len += (*s++ & 0xc0) != 0x80;
211     maxlen--;
212   }
213   return len;
214 }
215 
216 // remove the last *glyph* from the *utf8* string!
217 // this is different from just setting the last byte to 0 (in some
218 // cases ofc). The actual implementation is quite inefficient because
219 // it remove the last char until the number of glyphs doesn't change
220 void popc(char *p, int maxlen) {
221   int len = strnlen(p, maxlen);
222 
223   if (len == 0)
224     return;
225 
226   int ulen = utf8strnlen(p, maxlen);
227   while (len > 0 && utf8strnlen(p, maxlen) == ulen) {
228     len--;
229     p[len] = 0;
230   }
231 }
232 
233 // read an arbitrary long line from stdin and return a pointer to it
234 // TODO: resize the allocated memory to exactly fit the string once
235 // read?
236 char *readline(bool *eof) {
237   int maxlen = 8;
238   char *str = calloc(maxlen, sizeof(char));
239   if (str == nil) {
240     fprintf(stderr, "Cannot allocate memory!\n");
241     exit(EX_UNAVAILABLE);
242   }
243 
244   int c;
245   while((c = getchar()) != EOF) {
246     if (c == '\n')
247       return str;
248     else
249       maxlen = pushc(&str, maxlen, c);
250 
251     if (maxlen == -1) {
252       fprintf(stderr, "Cannot allocate memory!\n");
253       exit(EX_UNAVAILABLE);
254     }
255   }
256   *eof = true;
257   return str;
258 }
259 
260 int readlines (char **lines) {
261   bool finished = false;
262   int n = 0;
263   while (n < MAX_ITEMS) {
264     lines[n] = readline(&finished);
265 
266     if (strlen(lines[n]) == 0 || lines[n][0] == '\n')
267       --n; // forget about this line
268 
269     if (finished)
270       break;
271 
272     ++n;
273   }
274   /* for (n = 0; n < MAX_ITEMS -1; ++n) { */
275   /*   lines[n] = readline(&finished); */
276   /*   if (finished) */
277   /*     break; */
278   /* } */
279   n++;
280   lines[n] = nil;
281   return n;
282 }
283 
284 // |------------------|----------------------------------------------|
285 // | 20 char text     | completion | completion | completion | compl |
286 // |------------------|----------------------------------------------|
287 void draw_horizontally(struct rendering *r, char *text, struct completions *cs) {
288   // TODO: make these dynamic?
289   int prompt_width = 20; // char
290   int padding = 10;
291   /* int start_at = XTextWidth(r->font, " ", 1) * prompt_width + padding; */
292 
293   XRectangle rect;
294   int start_at = XmbTextExtents(*r->font, " ", 1, nil, &rect);
295   start_at = start_at * prompt_width + padding;
296 
297   int texty = (rect.height + r->height) >>1;
298 
299   XFillRectangle(r->d, r->w, r->prompt_bg, 0, 0, start_at, r->height);
300 
301   int text_len = strlen(text);
302   if (text_len > prompt_width)
303     text = text + (text_len - prompt_width);
304   /* XDrawString(r->d, r->w, r->prompt, padding, texty, text, MIN(text_len, prompt_width)); */
305   Xutf8DrawString(r->d, r->w, *r->font, r->prompt, padding, texty, text, MIN(text_len, prompt_width));
306 
307   XFillRectangle(r->d, r->w, r->completion_bg, start_at, 0, r->width, r->height);
308 
309   while (cs != nil) {
310     GC g = cs->selected ? r->completion_highlighted    : r->completion;
311     GC h = cs->selected ? r->completion_highlighted_bg : r->completion_bg;
312 
313     int len = strlen(cs->completion);
314     /* int text_width = XTextWidth(r->font, cs->completion, len); */
315     int text_width = XmbTextExtents(*r->font, cs->completion, len, nil, nil);
316 
317     XFillRectangle(r->d, r->w, h, start_at, 0, text_width + padding*2, r->height);
318 
319     /*  XDrawString(r->d, r->w,           g, start_at + padding, texty, cs->completion, len); */
320     Xutf8DrawString(r->d, r->w, *r->font, g, start_at + padding, texty, cs->completion, len);
321 
322     start_at += text_width + padding * 2;
323 
324     cs = cs->next;
325   }
326 
327   XFlush(r->d);
328 }
329 
330 // |-----------------------------------------------------------------|
331 // |  prompt                                                         |
332 // |-----------------------------------------------------------------|
333 // |  completion                                                     |
334 // |-----------------------------------------------------------------|
335 // |  completion                                                     |
336 // |-----------------------------------------------------------------|
337 // TODO: dunno why but in the call to Xutf8DrawString, by logic,
338 // should be padding and not padding*2, but the text doesn't seem to
339 // be vertically centered otherwise....
340 void draw_vertically(struct rendering *r, char *text, struct completions *cs) {
341   int padding = 10; // TODO make this dynamic
342 
343   XRectangle rect;
344   XmbTextExtents(*r->font, "fjpgl", 5, &rect, nil);
345   int start_at = rect.height + padding*2;
346 
347   XFillRectangle(r->d, r->w, r->completion_bg, 0, 0, r->width, r->height);
348   XFillRectangle(r->d, r->w, r->prompt_bg, 0, 0, r->width, start_at);
349   Xutf8DrawString(r->d, r->w, *r->font, r->prompt, padding, padding*2, text, strlen(text));
350 
351   while (cs != nil) {
352     GC g = cs->selected ? r->completion_highlighted    : r->completion;
353     GC h = cs->selected ? r->completion_highlighted_bg : r->completion_bg;
354 
355     int len = strlen(cs->completion);
356     XmbTextExtents(*r->font, cs->completion, len, &rect, nil);
357     XFillRectangle(r->d, r->w, h, 0, start_at, r->width, rect.height + padding*2);
358     Xutf8DrawString(r->d, r->w, *r->font, g, padding, start_at + padding*2, cs->completion, len);
359 
360     start_at += rect.height + padding *2;
361     cs = cs->next;
362   }
363 
364   XFlush(r->d);
365 }
366 
367 void draw(struct rendering *r, char *text, struct completions *cs) {
368   if (r->horizontal_layout)
369     draw_horizontally(r, text, cs);
370   else
371     draw_vertically(r, text, cs);
372 }
373 
374 /* Set some WM stuff */
375 void set_win_atoms_hints(Display *d, Window w, int width, int height) {
376   Atom type;
377   type = XInternAtom(d, "_NET_WM_WINDOW_TYPE_DOCK", false);
378   XChangeProperty(
379                   d,
380                   w,
381                   XInternAtom(d, "_NET_WM_WINDOW_TYPE", false),
382                   XInternAtom(d, "ATOM", false),
383                   32,
384                   PropModeReplace,
385                   (unsigned char *)&type,
386                   1
387                   );
388 
389   /* some window managers honor this properties */
390   type = XInternAtom(d, "_NET_WM_STATE_ABOVE", false);
391   XChangeProperty(d,
392                   w,
393                   XInternAtom(d, "_NET_WM_STATE", false),
394                   XInternAtom(d, "ATOM", false),
395                   32,
396                   PropModeReplace,
397                   (unsigned char *)&type,
398                   1
399                   );
400 
401   type = XInternAtom(d, "_NET_WM_STATE_FOCUSED", false);
402   XChangeProperty(d,
403                   w,
404                   XInternAtom(d, "_NET_WM_STATE", false),
405                   XInternAtom(d, "ATOM", false),
406                   32,
407                   PropModeAppend,
408                   (unsigned char *)&type,
409                   1
410                   );
411 
412   // setting window hints
413   XClassHint *class_hint = XAllocClassHint();
414   if (class_hint == nil) {
415     fprintf(stderr, "Could not allocate memory for class hint\n");
416     exit(EX_UNAVAILABLE);
417   }
418   class_hint->res_name = "mymenu";
419   class_hint->res_class = "mymenu";
420   XSetClassHint(d, w, class_hint);
421   XFree(class_hint);
422 
423   XSizeHints *size_hint = XAllocSizeHints();
424   if (size_hint == nil) {
425     fprintf(stderr, "Could not allocate memory for size hint\n");
426     exit(EX_UNAVAILABLE);
427   }
428   size_hint->min_width = width;
429   size_hint->base_width = width;
430   size_hint->min_height = height;
431   size_hint->base_height = height;
432 
433   XFlush(d);
434 }
435 
436 void get_wh(Display *d, Window *w, int *width, int *height) {
437   XWindowAttributes win_attr;
438   XGetWindowAttributes(d, *w, &win_attr);
439   *height = win_attr.height;
440   *width = win_attr.width;
441 }
442 
443 // I know this may seem a little hackish BUT is the only way I managed
444 // to actually grab that goddam keyboard. Only one call to
445 // XGrabKeyboard does not always end up with the keyboard grabbed!
446 int take_keyboard(Display *d, Window w) {
447   int i;
448   for (i = 0; i < 100; i++) {
449     if (XGrabKeyboard(d, w, True, GrabModeAsync, GrabModeAsync, CurrentTime) == GrabSuccess)
450       return 1;
451     usleep(1000);
452   }
453   return 0;
454 }
455 
456 void release_keyboard(Display *d) {
457   XUngrabKeyboard(d, CurrentTime);
458 }
459 
460 int parse_integer(const char *str, int default_value, int max) {
461   int len = strlen(str);
462   if (len > 0 && str[len-1] == '%') {
463     char *cpy = strdup(str);
464     check_allocation(cpy);
465     cpy[len-1] = '\0';
466     int val = parse_integer(cpy, default_value, max);
467     free(cpy);
468     return val * max / 100;
469   }
470 
471   errno = 0;
472   char *ep;
473   long lval = strtol(str, &ep, 10);
474   if (str[0] == '\0' || *ep != '\0') { // NaN
475     fprintf(stderr, "'%s' is not a valid number! Using %d as default.\n", str, default_value);
476     return default_value;
477   }
478   if ((errno == ERANGE && (lval == LONG_MAX || lval == LONG_MIN)) ||
479       (lval > INT_MAX || lval < INT_MIN)) {
480     fprintf(stderr, "%s out of range! Using %d as default.\n", str, default_value);
481     return default_value;
482   }
483   return lval;
484 }
485 
486 int parse_int_with_middle(const char *str, int default_value, int max, int self) {
487   if (!strcmp(str, "middle")) {
488     return (max - self)/2;
489   }
490   return parse_integer(str, default_value, max);
491 }
492 
493 int main() {
494   char *lines[MAX_ITEMS] = {0};
495   readlines(lines);
496 
497   setlocale(LC_ALL, getenv("LANG"));
498 
499   enum state status = LOOPING;
500 
501   // where the monitor start (used only with xinerama)
502   int offset_x = 0;
503   int offset_y = 0;
504 
505   // width and height of the window
506   int width = 400;
507   int height = 20;
508 
509   // position on the screen
510   int x = 0;
511   int y = 0;
512 
513   char *fontname = strdup("fixed");
514   check_allocation(fontname);
515 
516   int textlen = 10;
517   char *text = malloc(textlen * sizeof(char));
518   check_allocation(text);
519 
520   struct completions *cs = filter(text, lines);
521   bool nothing_selected = true;
522 
523   // start talking to xorg
524   Display *d = XOpenDisplay(nil);
525   if (d == nil) {
526     fprintf(stderr, "Could not open display!\n");
527     return EX_UNAVAILABLE;
528   }
529 
530   // get display size
531   // XXX: is getting the default root window dimension correct?
532   XWindowAttributes xwa;
533   XGetWindowAttributes(d, DefaultRootWindow(d), &xwa);
534   int d_width = xwa.width;
535   int d_height = xwa.height;
536 
537 #ifdef USE_XINERAMA
538   // TODO: this bit still needs to be improved
539   if (XineramaIsActive(d)) {
540     int monitors;
541     XineramaScreenInfo *info = XineramaQueryScreens(d, &monitors);
542     if (info)
543       for (int i = 0; i < monitors; ++i) {
544         if (INTERSECT(x, y, 1, 1, info[i].x_org, info[i].y_org, info[i].width, info[i].height)) {
545           offset_x = info[x].x_org;
546           offset_y = info[y].y_org;
547           d_width = info[i].width;
548           d_height = info[i].height;
549         }
550       }
551     XFree(info);
552   }
553 #endif
554 
555   /* fprintf(stderr, "offset_x:\t%d\n" */
556   /*                 "offset_y:\t%d\n" */
557   /*                 "d_width:\t%d\n" */
558   /*                 "d_height:\t%d\n" */
559   /*         , offset_x, offset_y, d_width, d_height); */
560 
561   Colormap cmap = DefaultColormap(d, DefaultScreen(d));
562   XColor p_fg, p_bg,
563     compl_fg, compl_bg,
564     compl_highlighted_fg, compl_highlighted_bg;
565 
566   bool horizontal_layout = true;
567 
568   // read resource
569   XrmInitialize();
570   char *xrm = XResourceManagerString(d);
571   XrmDatabase xdb = nil;
572   if (xrm != nil) {
573     xdb = XrmGetStringDatabase(xrm);
574     XrmValue value;
575     char *datatype[20];
576 
577     if (XrmGetResource(xdb, "MyMenu.font", "*", datatype, &value) == true) {
578       fontname = strdup(value.addr);
579       check_allocation(fontname);
580     }
581     else
582       fprintf(stderr, "no font defined, using %s\n", fontname);
583 
584     if (XrmGetResource(xdb, "MyMenu.layout", "*", datatype, &value) == true) {
585       char *v = strdup(value.addr);
586       check_allocation(v);
587       horizontal_layout = !strcmp(v, "horizontal");
588       free(v);
589     }
590     else
591       fprintf(stderr, "no layout defined, using horizontal\n");
592 
593     if (XrmGetResource(xdb, "MyMenu.width", "*", datatype, &value) == true)
594       width = parse_integer(value.addr, width, d_width);
595     else
596       fprintf(stderr, "no width defined, using %d\n", width);
597 
598     if (XrmGetResource(xdb, "MyMenu.height", "*", datatype, &value) == true)
599       height = parse_integer(value.addr, height, d_height);
600     else
601       fprintf(stderr, "no height defined, using %d\n", height);
602 
603     if (XrmGetResource(xdb, "MyMenu.x", "*", datatype, &value) == true)
604       x = parse_int_with_middle(value.addr, x, d_width, width);
605     else
606       fprintf(stderr, "no x defined, using %d\n", width);
607 
608     if (XrmGetResource(xdb, "MyMenu.y", "*", datatype, &value) == true)
609       y = parse_int_with_middle(value.addr, y, d_height, height);
610     else
611       fprintf(stderr, "no y defined, using %d\n", height);
612 
613     XColor tmp;
614     // TODO: tmp needs to be free'd after every allocation?
615 
616     // prompt
617     if (XrmGetResource(xdb, "MyMenu.prompt.foreground", "*", datatype, &value) == true)
618       XAllocNamedColor(d, cmap, value.addr, &p_fg, &tmp);
619     else
620       XAllocNamedColor(d, cmap, "white", &p_fg, &tmp);
621 
622     if (XrmGetResource(xdb, "MyMenu.prompt.background", "*", datatype, &value) == true)
623       XAllocNamedColor(d, cmap, value.addr, &p_bg, &tmp);
624     else
625       XAllocNamedColor(d, cmap, "black", &p_bg, &tmp);
626 
627     // completion
628     if (XrmGetResource(xdb, "MyMenu.completion.foreground", "*", datatype, &value) == true)
629       XAllocNamedColor(d, cmap, value.addr, &compl_fg, &tmp);
630     else
631       XAllocNamedColor(d, cmap, "white", &compl_fg, &tmp);
632 
633     if (XrmGetResource(xdb, "MyMenu.completion.background", "*", datatype, &value) == true)
634       XAllocNamedColor(d, cmap, value.addr, &compl_bg, &tmp);
635     else
636       XAllocNamedColor(d, cmap, "black", &compl_bg, &tmp);
637 
638     // completion highlighted
639     if (XrmGetResource(xdb, "MyMenu.completion_highlighted.foreground", "*", datatype, &value) == true)
640       XAllocNamedColor(d, cmap, value.addr, &compl_highlighted_fg, &tmp);
641     else
642       XAllocNamedColor(d, cmap, "black", &compl_highlighted_fg, &tmp);
643 
644     if (XrmGetResource(xdb, "MyMenu.completion_highlighted.background", "*", datatype, &value) == true)
645       XAllocNamedColor(d, cmap, value.addr, &compl_highlighted_bg, &tmp);
646     else
647       XAllocNamedColor(d, cmap, "white", &compl_highlighted_bg, &tmp);
648   } else {
649     XColor tmp;
650     XAllocNamedColor(d, cmap, "white", &p_fg, &tmp);
651     XAllocNamedColor(d, cmap, "black", &p_bg, &tmp);
652     XAllocNamedColor(d, cmap, "white", &compl_fg, &tmp);
653     XAllocNamedColor(d, cmap, "black", &compl_bg, &tmp);
654     XAllocNamedColor(d, cmap, "black", &compl_highlighted_fg, &tmp);
655     XAllocNamedColor(d, cmap, "white", &compl_highlighted_bg, &tmp);
656   }
657 
658   // load the font
659   /* XFontStruct *font = XLoadQueryFont(d, fontname); */
660   /* if (font == nil) { */
661   /*   fprintf(stderr, "Unable to load %s font\n", fontname); */
662   /*   font = XLoadQueryFont(d, "fixed"); */
663   /* } */
664   // load the font
665   char **missing_charset_list;
666   int missing_charset_count;
667   XFontSet font = XCreateFontSet(d, fontname, &missing_charset_list, &missing_charset_count, nil);
668   if (font == nil) {
669     fprintf(stderr, "Unable to load the font(s) %s\n", fontname);
670     return EX_UNAVAILABLE;
671   }
672 
673   // create the window
674   XSetWindowAttributes attr;
675 
676   Window w = XCreateWindow(d,                                   // display
677                            DefaultRootWindow(d),                // parent
678                            x + offset_x, y + offset_y,          // x y
679                            width, height,                       // w h
680                            0,                                   // border width
681                            DefaultDepth(d, DefaultScreen(d)),   // depth
682                            InputOutput,                         // class
683                            DefaultVisual(d, DefaultScreen(d)),  // visual
684                            0,                                   // value mask
685                            &attr);
686 
687   set_win_atoms_hints(d, w, width, height);
688 
689   // we want some events
690   XSelectInput(d, w, StructureNotifyMask | KeyPressMask | KeyReleaseMask | KeymapStateMask);
691 
692   // make the window appear on the screen
693   XMapWindow(d, w);
694 
695   // wait for the MapNotify event (i.e. the event "window rendered")
696   for (;;) {
697     XEvent e;
698     XNextEvent(d, &e);
699     if (e.type == MapNotify)
700       break;
701   }
702 
703   // get the *real* width & height after the window was rendered
704   get_wh(d, &w, &width, &height);
705 
706   // grab keyboard
707   take_keyboard(d, w);
708 
709   // Create some graphics contexts
710   XGCValues values;
711   /* values.font = font->fid; */
712 
713   struct rendering r = {
714     .d                          = d,
715     .w                          = w,
716     .prompt                     = XCreateGC(d, w, 0, &values),
717     .prompt_bg                  = XCreateGC(d, w, 0, &values),
718     .completion                 = XCreateGC(d, w, 0, &values),
719     .completion_bg              = XCreateGC(d, w, 0, &values),
720     .completion_highlighted     = XCreateGC(d, w, 0, &values),
721     .completion_highlighted_bg  = XCreateGC(d, w, 0, &values),
722     /* .prompt                     = XCreateGC(d, w, GCFont, &values), */
723     /* .prompt_bg                  = XCreateGC(d, w, GCFont, &values), */
724     /* .completion                 = XCreateGC(d, w, GCFont, &values), */
725     /* .completion_bg              = XCreateGC(d, w, GCFont, &values), */
726     /* .completion_highlighted     = XCreateGC(d, w, GCFont, &values), */
727     /* .completion_highlighted_bg  = XCreateGC(d, w, GCFont, &values), */
728     .width                      = width,
729     .height                     = height,
730     .font                       = &font,
731     .horizontal_layout          = horizontal_layout
732   };
733 
734   // load the colors in our GCs
735   XSetForeground(d, r.prompt, p_fg.pixel);
736   XSetForeground(d, r.prompt_bg, p_bg.pixel);
737   XSetForeground(d, r.completion, compl_fg.pixel);
738   XSetForeground(d, r.completion_bg, compl_bg.pixel);
739   XSetForeground(d, r.completion_highlighted, compl_highlighted_fg.pixel);
740   XSetForeground(d, r.completion_highlighted_bg, compl_highlighted_bg.pixel);
741 
742   // open the X input method
743   XIM xim = XOpenIM(d, xdb, resname, resclass);
744   check_allocation(xim);
745 
746   XIMStyles *xis = nil;
747   if (XGetIMValues(xim, XNQueryInputStyle, &xis, NULL) || !xis) {
748     fprintf(stderr, "Input Styles could not be retrieved\n");
749     return EX_UNAVAILABLE;
750   }
751 
752   XIMStyle bestMatchStyle = 0;
753   for (int i = 0; i < xis->count_styles; ++i) {
754     XIMStyle ts = xis->supported_styles[i];
755     if (ts == (XIMPreeditNothing | XIMStatusNothing)) {
756       bestMatchStyle = ts;
757       break;
758     }
759   }
760   XFree(xis);
761 
762   if (!bestMatchStyle) {
763     fprintf(stderr, "No matching input style could be determined\n");
764   }
765 
766   XIC xic = XCreateIC(xim, XNInputStyle, bestMatchStyle, XNClientWindow, w, XNFocusWindow, w, NULL);
767   check_allocation(xic);
768 
769   // draw the window for the first time
770   draw(&r, text, cs);
771 
772   // main loop
773   while (status == LOOPING) {
774     XEvent e;
775     XNextEvent(d, &e);
776 
777     if (XFilterEvent(&e, w))
778       continue;
779 
780     switch (e.type) {
781     case KeymapNotify:
782       XRefreshKeyboardMapping(&e.xmapping);
783       break;
784 
785     case KeyRelease: break; // ignore this
786 
787     case KeyPress: {
788       XKeyPressedEvent *ev = (XKeyPressedEvent*)&e;
789 
790       if (ev->keycode == XKeysymToKeycode(d, XK_Tab)) {
791         bool shift = (ev->state & ShiftMask);
792         struct completions *n = shift ? compl_select_prev(cs, nothing_selected)
793                                       : compl_select_next(cs, nothing_selected);
794         if (n != nil) {
795           nothing_selected = false;
796           free(text);
797           text = strdup(n->completion);
798           if (text == nil) {
799             fprintf(stderr, "Memory allocation error!\n");
800             status = ERR;
801             break;
802           }
803           textlen = strlen(text);
804         }
805         draw(&r, text, cs);
806         break;
807       }
808 
809       if (ev->keycode == XKeysymToKeycode(d, XK_BackSpace)) {
810         nothing_selected = true;
811         popc(text, textlen);
812         update_completions(cs, text, lines);
813         draw(&r, text, cs);
814         break;
815       }
816 
817       if (ev->keycode == XKeysymToKeycode(d, XK_Return)) {
818         status = OK;
819         break;
820       }
821 
822       if (ev->keycode == XKeysymToKeycode(d, XK_Escape)) {
823         status = ERR;
824         break;
825       }
826 
827       // try to read what the user pressed
828       int symbol = 0;
829       Status s = 0;
830       Xutf8LookupString(xic, ev, (char*)&symbol, 4, 0, &s);
831 
832       if (s == XBufferOverflow) {
833         // should not happen since there are no utf-8 characters
834         // larger than 24bits, but is something to be aware of when
835         // used to directly write to a string buffer
836         fprintf(stderr, "Buffer overflow when trying to create keyboard symbol map.\n");
837         break;
838       }
839       char *str = (char*)&symbol;
840 
841       if (ev->state & ControlMask) {
842         // check for some key bindings
843         if (!strcmp(str, "")) { // C-u
844           nothing_selected = true;
845           for (int i = 0; i < textlen; ++i)
846             text[i] = 0;
847           update_completions(cs, text, lines);
848         }
849         if (!strcmp(str, "")) { // C-h
850           nothing_selected = true;
851           popc(text, textlen);
852           update_completions(cs, text, lines);
853         }
854         if (!strcmp(str, "")) { // C-w
855           nothing_selected = true;
856 
857           // `textlen` is the length of the allocated string, not the
858           // length of the ACTUAL string
859           int p = strlen(text) - 1;
860           if (p >= 0) { // delete the current char
861             text[p] = 0;
862             p--;
863           }
864           while (p >= 0 && isalnum(text[p])) {
865             text[p] = 0;
866             p--;
867           }
868           // erase also trailing white space
869           while (p >= 0 && isspace(text[p])) {
870             text[p] = 0;
871             p--;
872           }
873           update_completions(cs, text, lines);
874         }
875         if (!strcmp(str, "\r")) { // C-m
876           status = OK;
877         }
878         draw(&r, text, cs);
879         break;
880       }
881 
882       int str_len = strlen(str);
883       for (int i = 0; i < str_len; ++i) {
884         textlen = pushc(&text, textlen, str[i]);
885         if (textlen == -1) {
886           fprintf(stderr, "Memory allocation error\n");
887           status = ERR;
888           break;
889         }
890         nothing_selected = true;
891         update_completions(cs, text, lines);
892       }
893 
894     }
895       draw(&r, text, cs);
896       break;
897 
898     default:
899       fprintf(stderr, "Unknown event %d\n", e.type);
900     }
901   }
902 
903   release_keyboard(d);
904 
905   if (status == OK)
906     printf("%s\n", text);
907 
908   free(fontname);
909   free(text);
910   compl_delete(cs);
911 
912   /* XDestroyWindow(d, w); */
913   XCloseDisplay(d);
914 
915   return status == OK ? 0 : 1;
916 }