d7482997 |
1 | /* |
2 | * misc.c: miscellaneous useful items |
3 | */ |
4 | |
e4ea58f8 |
5 | #include <stdarg.h> |
d7482997 |
6 | #include "halibut.h" |
7 | |
e4ea58f8 |
8 | char *adv(char *s) { |
9 | return s + 1 + strlen(s); |
10 | } |
11 | |
d7482997 |
12 | struct stackTag { |
13 | void **data; |
14 | int sp; |
15 | int size; |
16 | }; |
17 | |
18 | stack stk_new(void) { |
19 | stack s; |
20 | |
21 | s = mknew(struct stackTag); |
22 | s->sp = 0; |
23 | s->size = 0; |
24 | s->data = NULL; |
25 | |
26 | return s; |
27 | } |
28 | |
29 | void stk_free(stack s) { |
30 | sfree(s->data); |
31 | sfree(s); |
32 | } |
33 | |
34 | void stk_push(stack s, void *item) { |
35 | if (s->size <= s->sp) { |
36 | s->size = s->sp + 32; |
37 | s->data = resize(s->data, s->size); |
38 | } |
39 | s->data[s->sp++] = item; |
40 | } |
41 | |
42 | void *stk_pop(stack s) { |
43 | if (s->sp > 0) |
44 | return s->data[--s->sp]; |
45 | else |
46 | return NULL; |
47 | } |
48 | |
7136a6c7 |
49 | void *stk_top(stack s) { |
50 | if (s->sp > 0) |
51 | return s->data[s->sp-1]; |
52 | else |
53 | return NULL; |
54 | } |
55 | |
d7482997 |
56 | /* |
57 | * Small routines to amalgamate a string from an input source. |
58 | */ |
59 | const rdstring empty_rdstring = {0, 0, NULL}; |
60 | const rdstringc empty_rdstringc = {0, 0, NULL}; |
61 | |
62 | void rdadd(rdstring *rs, wchar_t c) { |
63 | if (rs->pos >= rs->size-1) { |
64 | rs->size = rs->pos + 128; |
65 | rs->text = resize(rs->text, rs->size); |
66 | } |
67 | rs->text[rs->pos++] = c; |
68 | rs->text[rs->pos] = 0; |
69 | } |
5dd44dce |
70 | void rdadds(rdstring *rs, wchar_t const *p) { |
d7482997 |
71 | int len = ustrlen(p); |
72 | if (rs->pos >= rs->size - len) { |
73 | rs->size = rs->pos + len + 128; |
74 | rs->text = resize(rs->text, rs->size); |
75 | } |
76 | ustrcpy(rs->text + rs->pos, p); |
77 | rs->pos += len; |
78 | } |
79 | wchar_t *rdtrim(rdstring *rs) { |
80 | rs->text = resize(rs->text, rs->pos + 1); |
81 | return rs->text; |
82 | } |
83 | |
84 | void rdaddc(rdstringc *rs, char c) { |
85 | if (rs->pos >= rs->size-1) { |
86 | rs->size = rs->pos + 128; |
87 | rs->text = resize(rs->text, rs->size); |
88 | } |
89 | rs->text[rs->pos++] = c; |
90 | rs->text[rs->pos] = 0; |
91 | } |
5dd44dce |
92 | void rdaddsc(rdstringc *rs, char const *p) { |
d7482997 |
93 | int len = strlen(p); |
94 | if (rs->pos >= rs->size - len) { |
95 | rs->size = rs->pos + len + 128; |
96 | rs->text = resize(rs->text, rs->size); |
97 | } |
98 | strcpy(rs->text + rs->pos, p); |
99 | rs->pos += len; |
100 | } |
101 | char *rdtrimc(rdstringc *rs) { |
102 | rs->text = resize(rs->text, rs->pos + 1); |
103 | return rs->text; |
104 | } |
105 | |
831da32e |
106 | static int compare_wordlists_literally(word *a, word *b) { |
d7482997 |
107 | int t; |
108 | while (a && b) { |
109 | if (a->type != b->type) |
110 | return (a->type < b->type ? -1 : +1); /* FIXME? */ |
111 | t = a->type; |
112 | if ((t != word_Normal && t != word_Code && |
113 | t != word_WeakCode && t != word_Emph) || |
114 | a->alt || b->alt) { |
115 | int c; |
116 | if (a->text && b->text) { |
117 | c = ustricmp(a->text, b->text); |
118 | if (c) |
119 | return c; |
120 | } |
831da32e |
121 | c = compare_wordlists_literally(a->alt, b->alt); |
d7482997 |
122 | if (c) |
123 | return c; |
124 | a = a->next; |
125 | b = b->next; |
126 | } else { |
127 | wchar_t *ap = a->text, *bp = b->text; |
128 | while (*ap && *bp) { |
129 | wchar_t ac = utolower(*ap), bc = utolower(*bp); |
130 | if (ac != bc) |
131 | return (ac < bc ? -1 : +1); |
132 | if (!*++ap && a->next && a->next->type == t && !a->next->alt) |
133 | a = a->next, ap = a->text; |
134 | if (!*++bp && b->next && b->next->type == t && !b->next->alt) |
135 | b = b->next, bp = b->text; |
136 | } |
137 | if (*ap || *bp) |
138 | return (*ap ? +1 : -1); |
139 | a = a->next; |
140 | b = b->next; |
141 | } |
142 | } |
143 | |
144 | if (a || b) |
145 | return (a ? +1 : -1); |
146 | else |
147 | return 0; |
148 | } |
149 | |
831da32e |
150 | int compare_wordlists(word *a, word *b) { |
151 | /* |
152 | * First we compare only the alphabetic content of the word |
153 | * lists, with case not a factor. If that comes out equal, |
154 | * _then_ we compare the word lists literally. |
155 | */ |
156 | struct { |
157 | word *w; |
158 | int i; |
159 | wchar_t c; |
160 | } pos[2]; |
161 | |
162 | pos[0].w = a; |
163 | pos[1].w = b; |
164 | pos[0].i = pos[1].i = 0; |
165 | |
166 | while (1) { |
167 | /* |
168 | * Find the next alphabetic character in each word list. |
169 | */ |
170 | int k; |
171 | |
172 | for (k = 0; k < 2; k++) { |
173 | /* |
174 | * Advance until we hit either an alphabetic character |
175 | * or the end of the word list. |
176 | */ |
177 | while (1) { |
178 | if (!pos[k].w) { |
179 | /* End of word list. */ |
180 | pos[k].c = 0; |
181 | break; |
182 | } else if (!pos[k].w->text || !pos[k].w->text[pos[k].i]) { |
183 | /* No characters remaining in this word; move on. */ |
184 | pos[k].w = pos[k].w->next; |
185 | pos[k].i = 0; |
186 | } else if (!uisalpha(pos[k].w->text[pos[k].i])) { |
187 | /* This character isn't alphabetic; move on. */ |
188 | pos[k].i++; |
189 | } else { |
190 | /* We have an alphabetic! Lowercase it and continue. */ |
191 | pos[k].c = utolower(pos[k].w->text[pos[k].i]); |
192 | break; |
193 | } |
194 | } |
195 | } |
196 | |
197 | if (pos[0].c < pos[1].c) |
198 | return -1; |
199 | else if (pos[0].c > pos[1].c) |
200 | return +1; |
201 | |
202 | if (!pos[0].c) |
203 | break; /* they're equal */ |
204 | |
205 | pos[0].i++; |
206 | pos[1].i++; |
207 | } |
208 | |
209 | /* |
210 | * If we reach here, the strings were alphabetically equal, so |
211 | * compare in more detail. |
212 | */ |
213 | return compare_wordlists_literally(a, b); |
214 | } |
215 | |
d7482997 |
216 | void mark_attr_ends(paragraph *sourceform) { |
217 | paragraph *p; |
218 | word *w, *wp; |
219 | for (p = sourceform; p; p = p->next) { |
220 | wp = NULL; |
221 | for (w = p->words; w; w = w->next) { |
222 | if (isattr(w->type)) { |
223 | int before = (wp && isattr(wp->type) && |
224 | sameattr(wp->type, w->type)); |
225 | int after = (w->next && isattr(w->next->type) && |
226 | sameattr(w->next->type, w->type)); |
227 | w->aux |= (before ? |
228 | (after ? attr_Always : attr_Last) : |
229 | (after ? attr_First : attr_Only)); |
230 | } |
231 | wp = w; |
232 | } |
233 | } |
234 | } |
235 | |
43341922 |
236 | /* |
237 | * This function implements the optimal paragraph wrapping |
238 | * algorithm, pretty much as used in TeX. A cost function is |
239 | * defined for each line of the wrapped paragraph (typically some |
240 | * convex function of the difference between the line's length and |
241 | * its desired length), and a dynamic programming approach is used |
242 | * to optimise globally across all possible layouts of the |
243 | * paragraph to find the one with the minimum total cost. |
244 | * |
245 | * The function as implemented here gives a choice of two options |
246 | * for the cost function: |
247 | * |
248 | * - If `natural_space' is zero, then the algorithm attempts to |
249 | * make each line the maximum possible width (either `width' or |
250 | * `subsequentwidth' depending on whether it's the first line of |
251 | * the paragraph or not), and the cost function is simply the |
252 | * square of the unused space at the end of each line. This is a |
253 | * simple mechanism suitable for use in fixed-pitch environments |
254 | * such as plain text displayed on a terminal. |
255 | * |
256 | * - However, if `natural_space' is positive, the algorithm |
257 | * assumes the medium is fully graphical and that the width of |
258 | * space characters can be adjusted finely, and it attempts to |
259 | * make each _space character_ the width given in |
260 | * `natural_space'. (The provided width function should return |
261 | * the _minimum_ acceptable width of a space character in this |
262 | * case.) Therefore, the cost function for a line is dependent |
263 | * on the number of spaces on that line as well as the amount by |
264 | * which the line width differs from the optimum. |
265 | */ |
d7482997 |
266 | wrappedline *wrap_para(word *text, int width, int subsequentwidth, |
43341922 |
267 | int (*widthfn)(void *, word *), void *ctx, |
268 | int natural_space) { |
d7482997 |
269 | wrappedline *head = NULL, **ptr = &head; |
270 | int nwords, wordsize; |
271 | struct wrapword { |
272 | word *begin, *end; |
273 | int width; |
274 | int spacewidth; |
275 | int cost; |
276 | int nwords; |
277 | } *wrapwords; |
278 | int i, j, n; |
279 | |
280 | /* |
281 | * Break the line up into wrappable components. |
282 | */ |
283 | nwords = wordsize = 0; |
284 | wrapwords = NULL; |
285 | while (text) { |
286 | if (nwords >= wordsize) { |
287 | wordsize = nwords + 64; |
288 | wrapwords = srealloc(wrapwords, wordsize * sizeof(*wrapwords)); |
289 | } |
290 | wrapwords[nwords].width = 0; |
291 | wrapwords[nwords].begin = text; |
292 | while (text) { |
43341922 |
293 | wrapwords[nwords].width += widthfn(ctx, text); |
d7482997 |
294 | wrapwords[nwords].end = text->next; |
295 | if (text->next && (text->next->type == word_WhiteSpace || |
296 | text->next->type == word_EmphSpace || |
297 | text->breaks)) |
298 | break; |
299 | text = text->next; |
300 | } |
301 | if (text && text->next && (text->next->type == word_WhiteSpace || |
302 | text->next->type == word_EmphSpace)) { |
43341922 |
303 | wrapwords[nwords].spacewidth = widthfn(ctx, text->next); |
d7482997 |
304 | text = text->next; |
305 | } else { |
306 | wrapwords[nwords].spacewidth = 0; |
307 | } |
308 | nwords++; |
309 | if (text) |
310 | text = text->next; |
311 | } |
312 | |
313 | /* |
314 | * Perform the dynamic wrapping algorithm: work backwards from |
315 | * nwords-1, determining the optimal wrapping for each terminal |
316 | * subsequence of the paragraph. |
317 | */ |
318 | for (i = nwords; i-- ;) { |
319 | int best = -1; |
320 | int bestcost = 0; |
321 | int cost; |
43341922 |
322 | int linelen = 0, spacewidth = 0, minspacewidth = 0; |
323 | int nspaces; |
d7482997 |
324 | int thiswidth = (i == 0 ? width : subsequentwidth); |
325 | |
326 | j = 0; |
43341922 |
327 | nspaces = 0; |
d7482997 |
328 | while (i+j < nwords) { |
329 | /* |
330 | * See what happens if we put j+1 words on this line. |
331 | */ |
43341922 |
332 | if (spacewidth) { |
333 | nspaces++; |
334 | minspacewidth = spacewidth; |
335 | } |
d7482997 |
336 | linelen += spacewidth + wrapwords[i+j].width; |
337 | spacewidth = wrapwords[i+j].spacewidth; |
338 | j++; |
339 | if (linelen > thiswidth) { |
340 | /* |
341 | * If we're over the width limit, abandon ship, |
342 | * _unless_ there is no best-effort yet (which will |
343 | * only happen if the first word is too long all by |
344 | * itself). |
345 | */ |
346 | if (best > 0) |
347 | break; |
348 | } |
43341922 |
349 | |
350 | /* |
351 | * Compute the cost of this line. The method of doing |
352 | * this differs hugely depending on whether |
353 | * natural_space is nonzero or not. |
354 | */ |
355 | if (natural_space) { |
356 | if (!nspaces && linelen > thiswidth) { |
357 | /* |
358 | * Special case: if there are no spaces at all |
359 | * on the line because one single word is too |
360 | * long for its line, cost is zero because |
361 | * there's nothing we can do about it anyway. |
362 | */ |
363 | cost = 0; |
364 | } else { |
365 | int shortfall = thiswidth - linelen; |
366 | int spaceextra = shortfall / (nspaces ? nspaces : 1); |
367 | int spaceshortfall = natural_space - |
368 | (minspacewidth + spaceextra); |
369 | |
370 | if (i+j == nwords && spaceshortfall < 0) { |
371 | /* |
372 | * Special case: on the very last line of |
373 | * the paragraph, we don't score penalty |
374 | * points for having to _stretch_ the line, |
375 | * since we won't stretch it anyway. |
376 | * However, we score penalties as normal |
377 | * for having to squeeze it. |
378 | */ |
379 | cost = 0; |
380 | } else { |
381 | /* |
382 | * Squaring this number is tricky since |
383 | * it's liable to be quite big. Let's |
384 | * divide it through by 256. |
385 | */ |
386 | int x = spaceshortfall >> 8; |
387 | int xf = spaceshortfall & 0xFF; |
388 | |
389 | /* |
390 | * Not counting strange variable-fixed- |
391 | * point oddities, we are computing |
392 | * |
393 | * (x+xf)^2 = x^2 + 2*x*xf + xf*xf |
394 | * |
395 | * except that _our_ xf is 256 times the |
396 | * one listed there. |
397 | */ |
398 | |
399 | cost = x * x; |
400 | cost += (2 * x * xf) >> 8; |
401 | } |
402 | } |
d7482997 |
403 | } else { |
43341922 |
404 | if (i+j == nwords) { |
405 | /* |
406 | * Special case: if we're at the very end of the |
407 | * paragraph, we don't score penalty points for the |
408 | * white space left on the line. |
409 | */ |
410 | cost = 0; |
411 | } else { |
412 | cost = (thiswidth-linelen) * (thiswidth-linelen); |
413 | } |
d7482997 |
414 | } |
43341922 |
415 | |
416 | /* |
417 | * Add in the cost of wrapping all lines after this |
418 | * point too. |
419 | */ |
420 | if (i+j < nwords) |
421 | cost += wrapwords[i+j].cost; |
422 | |
d7482997 |
423 | /* |
424 | * We compare bestcost >= cost, not bestcost > cost, |
425 | * because in cases where the costs are identical we |
426 | * want to try to look like the greedy algorithm, |
427 | * because readers are likely to have spent a lot of |
428 | * time looking at greedy-wrapped paragraphs and |
429 | * there's no point violating the Principle of Least |
430 | * Surprise if it doesn't actually gain anything. |
431 | */ |
432 | if (best < 0 || bestcost >= cost) { |
433 | bestcost = cost; |
434 | best = j; |
435 | } |
436 | } |
437 | /* |
438 | * Now we know the optimal answer for this terminal |
439 | * subsequence, so put it in wrapwords. |
440 | */ |
441 | wrapwords[i].cost = bestcost; |
442 | wrapwords[i].nwords = best; |
443 | } |
444 | |
445 | /* |
446 | * We've wrapped the paragraph. Now build the output |
447 | * `wrappedline' list. |
448 | */ |
449 | i = 0; |
450 | while (i < nwords) { |
451 | wrappedline *w = mknew(wrappedline); |
452 | *ptr = w; |
453 | ptr = &w->next; |
454 | w->next = NULL; |
455 | |
456 | n = wrapwords[i].nwords; |
457 | w->begin = wrapwords[i].begin; |
458 | w->end = wrapwords[i+n-1].end; |
459 | |
460 | /* |
461 | * Count along the words to find nspaces and shortfall. |
462 | */ |
463 | w->nspaces = 0; |
464 | w->shortfall = width; |
465 | for (j = 0; j < n; j++) { |
466 | w->shortfall -= wrapwords[i+j].width; |
467 | if (j < n-1 && wrapwords[i+j].spacewidth) { |
468 | w->nspaces++; |
469 | w->shortfall -= wrapwords[i+j].spacewidth; |
470 | } |
471 | } |
472 | i += n; |
473 | } |
474 | |
475 | sfree(wrapwords); |
476 | |
477 | return head; |
478 | } |
479 | |
480 | void wrap_free(wrappedline *w) { |
481 | while (w) { |
482 | wrappedline *t = w->next; |
483 | sfree(w); |
484 | w = t; |
485 | } |
486 | } |
e4ea58f8 |
487 | |
488 | void cmdline_cfg_add(paragraph *cfg, char *string) |
489 | { |
490 | wchar_t *ustring; |
491 | int upos, ulen, pos, len; |
492 | |
493 | ulen = 0; |
494 | while (cfg->keyword[ulen]) |
495 | ulen += 1 + ustrlen(cfg->keyword+ulen); |
496 | len = 0; |
497 | while (cfg->origkeyword[len]) |
498 | len += 1 + strlen(cfg->origkeyword+len); |
499 | |
500 | ustring = ufroma_dup(string, CS_FIXME); |
501 | |
502 | upos = ulen; |
503 | ulen += 2 + ustrlen(ustring); |
504 | cfg->keyword = resize(cfg->keyword, ulen); |
505 | ustrcpy(cfg->keyword+upos, ustring); |
506 | cfg->keyword[ulen-1] = L'\0'; |
507 | |
508 | pos = len; |
509 | len += 2 + strlen(string); |
510 | cfg->origkeyword = resize(cfg->origkeyword, len); |
511 | strcpy(cfg->origkeyword+pos, string); |
512 | cfg->origkeyword[len-1] = '\0'; |
513 | |
514 | sfree(ustring); |
515 | } |
516 | |
517 | paragraph *cmdline_cfg_new(void) |
518 | { |
519 | paragraph *p; |
520 | |
521 | p = mknew(paragraph); |
522 | memset(p, 0, sizeof(*p)); |
523 | p->type = para_Config; |
524 | p->next = NULL; |
525 | p->fpos.filename = "<command line>"; |
526 | p->fpos.line = p->fpos.col = -1; |
527 | p->keyword = ustrdup(L"\0"); |
528 | p->origkeyword = dupstr("\0"); |
529 | |
530 | return p; |
531 | } |
532 | |
533 | paragraph *cmdline_cfg_simple(char *string, ...) |
534 | { |
535 | va_list ap; |
536 | char *s; |
537 | paragraph *p; |
538 | |
539 | p = cmdline_cfg_new(); |
540 | cmdline_cfg_add(p, string); |
541 | |
542 | va_start(ap, string); |
543 | while ((s = va_arg(ap, char *)) != NULL) |
544 | cmdline_cfg_add(p, s); |
545 | va_end(ap); |
546 | |
547 | return p; |
548 | } |