xref: /openbsd-src/usr.bin/mandoc/out.c (revision 824adb5411e4389b29bae28eba5c2c2bbd147f34)
1 /*	$OpenBSD: out.c,v 1.55 2021/09/28 17:06:17 schwarze Exp $ */
2 /*
3  * Copyright (c) 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
4  * Copyright (c) 2011, 2014, 2015, 2017, 2018, 2019, 2021
5  *               Ingo Schwarze <schwarze@openbsd.org>
6  *
7  * Permission to use, copy, modify, and distribute this software for any
8  * purpose with or without fee is hereby granted, provided that the above
9  * copyright notice and this permission notice appear in all copies.
10  *
11  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18  */
19 #include <sys/types.h>
20 
21 #include <assert.h>
22 #include <ctype.h>
23 #include <stdint.h>
24 #include <stdio.h>
25 #include <stdlib.h>
26 #include <string.h>
27 #include <time.h>
28 
29 #include "mandoc_aux.h"
30 #include "mandoc.h"
31 #include "tbl.h"
32 #include "out.h"
33 
34 struct	tbl_colgroup {
35 	struct tbl_colgroup	*next;
36 	size_t			 wanted;
37 	int			 startcol;
38 	int			 endcol;
39 };
40 
41 static	size_t	tblcalc_data(struct rofftbl *, struct roffcol *,
42 			const struct tbl_opts *, const struct tbl_dat *,
43 			size_t);
44 static	size_t	tblcalc_literal(struct rofftbl *, struct roffcol *,
45 			const struct tbl_dat *, size_t);
46 static	size_t	tblcalc_number(struct rofftbl *, struct roffcol *,
47 			const struct tbl_opts *, const struct tbl_dat *);
48 
49 
50 /*
51  * Parse the *src string and store a scaling unit into *dst.
52  * If the string doesn't specify the unit, use the default.
53  * If no default is specified, fail.
54  * Return a pointer to the byte after the last byte used,
55  * or NULL on total failure.
56  */
57 const char *
58 a2roffsu(const char *src, struct roffsu *dst, enum roffscale def)
59 {
60 	char		*endptr;
61 
62 	dst->unit = def == SCALE_MAX ? SCALE_BU : def;
63 	dst->scale = strtod(src, &endptr);
64 	if (endptr == src)
65 		return NULL;
66 
67 	switch (*endptr++) {
68 	case 'c':
69 		dst->unit = SCALE_CM;
70 		break;
71 	case 'i':
72 		dst->unit = SCALE_IN;
73 		break;
74 	case 'f':
75 		dst->unit = SCALE_FS;
76 		break;
77 	case 'M':
78 		dst->unit = SCALE_MM;
79 		break;
80 	case 'm':
81 		dst->unit = SCALE_EM;
82 		break;
83 	case 'n':
84 		dst->unit = SCALE_EN;
85 		break;
86 	case 'P':
87 		dst->unit = SCALE_PC;
88 		break;
89 	case 'p':
90 		dst->unit = SCALE_PT;
91 		break;
92 	case 'u':
93 		dst->unit = SCALE_BU;
94 		break;
95 	case 'v':
96 		dst->unit = SCALE_VS;
97 		break;
98 	default:
99 		endptr--;
100 		if (SCALE_MAX == def)
101 			return NULL;
102 		dst->unit = def;
103 		break;
104 	}
105 	return endptr;
106 }
107 
108 /*
109  * Calculate the abstract widths and decimal positions of columns in a
110  * table.  This routine allocates the columns structures then runs over
111  * all rows and cells in the table.  The function pointers in "tbl" are
112  * used for the actual width calculations.
113  */
114 void
115 tblcalc(struct rofftbl *tbl, const struct tbl_span *sp_first,
116     size_t offset, size_t rmargin)
117 {
118 	struct roffsu		 su;
119 	const struct tbl_opts	*opts;
120 	const struct tbl_span	*sp;
121 	const struct tbl_dat	*dp;
122 	struct roffcol		*col;
123 	struct tbl_colgroup	*first_group, **gp, *g;
124 	size_t			*colwidth;
125 	size_t			 ewidth, min1, min2, wanted, width, xwidth;
126 	int			 done, icol, maxcol, necol, nxcol, quirkcol;
127 
128 	/*
129 	 * Allocate the master column specifiers.  These will hold the
130 	 * widths and decimal positions for all cells in the column.  It
131 	 * must be freed and nullified by the caller.
132 	 */
133 
134 	assert(tbl->cols == NULL);
135 	tbl->cols = mandoc_calloc((size_t)sp_first->opts->cols,
136 	    sizeof(struct roffcol));
137 	opts = sp_first->opts;
138 
139 	maxcol = -1;
140 	first_group = NULL;
141 	for (sp = sp_first; sp != NULL; sp = sp->next) {
142 		if (sp->pos != TBL_SPAN_DATA)
143 			continue;
144 
145 		/*
146 		 * Account for the data cells in the layout, matching it
147 		 * to data cells in the data section.
148 		 */
149 
150 		gp = &first_group;
151 		for (dp = sp->first; dp != NULL; dp = dp->next) {
152 			icol = dp->layout->col;
153 			while (maxcol < icol + dp->hspans)
154 				tbl->cols[++maxcol].spacing = SIZE_MAX;
155 			col = tbl->cols + icol;
156 			col->flags |= dp->layout->flags;
157 			if (dp->layout->flags & TBL_CELL_WIGN)
158 				continue;
159 
160 			/* Handle explicit width specifications. */
161 
162 			if (dp->layout->wstr != NULL &&
163 			    dp->layout->width == 0 &&
164 			    a2roffsu(dp->layout->wstr, &su, SCALE_EN)
165 			    != NULL)
166 				dp->layout->width =
167 				    (*tbl->sulen)(&su, tbl->arg);
168 			if (col->width < dp->layout->width)
169 				col->width = dp->layout->width;
170 			if (dp->layout->spacing != SIZE_MAX &&
171 			    (col->spacing == SIZE_MAX ||
172 			     col->spacing < dp->layout->spacing))
173 				col->spacing = dp->layout->spacing;
174 
175 			/*
176 			 * Calculate an automatic width.
177 			 * Except for spanning cells, apply it.
178 			 */
179 
180 			width = tblcalc_data(tbl,
181 			    dp->hspans == 0 ? col : NULL,
182 			    opts, dp,
183 			    dp->block == 0 ? 0 :
184 			    dp->layout->width ? dp->layout->width :
185 			    rmargin ? (rmargin + sp->opts->cols / 2)
186 			    / (sp->opts->cols + 1) : 0);
187 			if (dp->hspans == 0)
188 				continue;
189 
190 			/*
191 			 * Build an ordered, singly linked list
192 			 * of all groups of columns joined by spans,
193 			 * recording the minimum width for each group.
194 			 */
195 
196 			while (*gp != NULL && ((*gp)->startcol < icol ||
197 			    (*gp)->endcol < icol + dp->hspans))
198 				gp = &(*gp)->next;
199 			if (*gp == NULL || (*gp)->startcol > icol ||
200                             (*gp)->endcol > icol + dp->hspans) {
201 				g = mandoc_malloc(sizeof(*g));
202 				g->next = *gp;
203 				g->wanted = width;
204 				g->startcol = icol;
205 				g->endcol = icol + dp->hspans;
206 				*gp = g;
207 			} else if ((*gp)->wanted < width)
208 				(*gp)->wanted = width;
209 		}
210 	}
211 
212 	/*
213 	 * The minimum width of columns explicitly specified
214 	 * in the layout is 1n.
215 	 */
216 
217 	if (maxcol < sp_first->opts->cols - 1)
218 		maxcol = sp_first->opts->cols - 1;
219 	for (icol = 0; icol <= maxcol; icol++) {
220 		col = tbl->cols + icol;
221 		if (col->width < 1)
222 			col->width = 1;
223 
224 		/*
225 		 * Column spacings are needed for span width
226 		 * calculations, so set the default values now.
227 		 */
228 
229 		if (col->spacing == SIZE_MAX || icol == maxcol)
230 			col->spacing = 3;
231 	}
232 
233 	/*
234 	 * Replace the minimum widths with the missing widths,
235 	 * and dismiss groups that are already wide enough.
236 	 */
237 
238 	gp = &first_group;
239 	while ((g = *gp) != NULL) {
240 		done = 0;
241 		for (icol = g->startcol; icol <= g->endcol; icol++) {
242 			width = tbl->cols[icol].width;
243 			if (icol < g->endcol)
244 				width += tbl->cols[icol].spacing;
245 			if (g->wanted <= width) {
246 				done = 1;
247 				break;
248 			} else
249 				(*gp)->wanted -= width;
250 		}
251 		if (done) {
252 			*gp = g->next;
253 			free(g);
254 		} else
255 			gp = &(*gp)->next;
256 	}
257 
258 	colwidth = mandoc_reallocarray(NULL, maxcol + 1, sizeof(*colwidth));
259 	while (first_group != NULL) {
260 
261 		/*
262 		 * Rebuild the array of the widths of all columns
263 		 * participating in spans that require expansion.
264 		 */
265 
266 		for (icol = 0; icol <= maxcol; icol++)
267 			colwidth[icol] = SIZE_MAX;
268 		for (g = first_group; g != NULL; g = g->next)
269 			for (icol = g->startcol; icol <= g->endcol; icol++)
270 				colwidth[icol] = tbl->cols[icol].width;
271 
272 		/*
273 		 * Find the smallest and second smallest column width
274 		 * among the columns which may need expamsion.
275 		 */
276 
277 		min1 = min2 = SIZE_MAX;
278 		for (icol = 0; icol <= maxcol; icol++) {
279 			width = colwidth[icol];
280 			if (min1 > width) {
281 				min2 = min1;
282 				min1 = width;
283 			} else if (min1 < width && min2 > width)
284 				min2 = width;
285 		}
286 
287 		/*
288 		 * Find the minimum wanted width
289 		 * for any one of the narrowest columns,
290 		 * and mark the columns wanting that width.
291 		 */
292 
293 		wanted = min2;
294 		for (g = first_group; g != NULL; g = g->next) {
295 			necol = 0;
296 			for (icol = g->startcol; icol <= g->endcol; icol++)
297 				if (colwidth[icol] == min1)
298 					necol++;
299 			if (necol == 0)
300 				continue;
301 			width = min1 + (g->wanted - 1) / necol + 1;
302 			if (width > min2)
303 				width = min2;
304 			if (wanted > width)
305 				wanted = width;
306 		}
307 
308 		/* Record the effect of the widening. */
309 
310 		gp = &first_group;
311 		while ((g = *gp) != NULL) {
312 			done = 0;
313 			for (icol = g->startcol; icol <= g->endcol; icol++) {
314 				if (colwidth[icol] != min1)
315 					continue;
316 				if (g->wanted <= wanted - min1) {
317 					tbl->cols[icol].width += g->wanted;
318 					done = 1;
319 					break;
320 				}
321 				tbl->cols[icol].width = wanted;
322 				g->wanted -= wanted - min1;
323 			}
324 			if (done) {
325 				*gp = g->next;
326 				free(g);
327 			} else
328 				gp = &(*gp)->next;
329 		}
330 	}
331 	free(colwidth);
332 
333 	/*
334 	 * Align numbers with text.
335 	 * Count columns to equalize and columns to maximize.
336 	 * Find maximum width of the columns to equalize.
337 	 * Find total width of the columns *not* to maximize.
338 	 */
339 
340 	necol = nxcol = 0;
341 	ewidth = xwidth = 0;
342 	for (icol = 0; icol <= maxcol; icol++) {
343 		col = tbl->cols + icol;
344 		if (col->width > col->nwidth)
345 			col->decimal += (col->width - col->nwidth) / 2;
346 		if (col->flags & TBL_CELL_EQUAL) {
347 			necol++;
348 			if (ewidth < col->width)
349 				ewidth = col->width;
350 		}
351 		if (col->flags & TBL_CELL_WMAX)
352 			nxcol++;
353 		else
354 			xwidth += col->width;
355 	}
356 
357 	/*
358 	 * Equalize columns, if requested for any of them.
359 	 * Update total width of the columns not to maximize.
360 	 */
361 
362 	if (necol) {
363 		for (icol = 0; icol <= maxcol; icol++) {
364 			col = tbl->cols + icol;
365 			if ( ! (col->flags & TBL_CELL_EQUAL))
366 				continue;
367 			if (col->width == ewidth)
368 				continue;
369 			if (nxcol && rmargin)
370 				xwidth += ewidth - col->width;
371 			col->width = ewidth;
372 		}
373 	}
374 
375 	/*
376 	 * If there are any columns to maximize, find the total
377 	 * available width, deducting 3n margins between columns.
378 	 * Distribute the available width evenly.
379 	 */
380 
381 	if (nxcol && rmargin) {
382 		xwidth += 3*maxcol +
383 		    (opts->opts & (TBL_OPT_BOX | TBL_OPT_DBOX) ?
384 		     2 : !!opts->lvert + !!opts->rvert);
385 		if (rmargin <= offset + xwidth)
386 			return;
387 		xwidth = rmargin - offset - xwidth;
388 
389 		/*
390 		 * Emulate a bug in GNU tbl width calculation that
391 		 * manifests itself for large numbers of x-columns.
392 		 * Emulating it for 5 x-columns gives identical
393 		 * behaviour for up to 6 x-columns.
394 		 */
395 
396 		if (nxcol == 5) {
397 			quirkcol = xwidth % nxcol + 2;
398 			if (quirkcol != 3 && quirkcol != 4)
399 				quirkcol = -1;
400 		} else
401 			quirkcol = -1;
402 
403 		necol = 0;
404 		ewidth = 0;
405 		for (icol = 0; icol <= maxcol; icol++) {
406 			col = tbl->cols + icol;
407 			if ( ! (col->flags & TBL_CELL_WMAX))
408 				continue;
409 			col->width = (double)xwidth * ++necol / nxcol
410 			    - ewidth + 0.4995;
411 			if (necol == quirkcol)
412 				col->width--;
413 			ewidth += col->width;
414 		}
415 	}
416 }
417 
418 static size_t
419 tblcalc_data(struct rofftbl *tbl, struct roffcol *col,
420     const struct tbl_opts *opts, const struct tbl_dat *dp, size_t mw)
421 {
422 	size_t		 sz;
423 
424 	/* Branch down into data sub-types. */
425 
426 	switch (dp->layout->pos) {
427 	case TBL_CELL_HORIZ:
428 	case TBL_CELL_DHORIZ:
429 		sz = (*tbl->len)(1, tbl->arg);
430 		if (col != NULL && col->width < sz)
431 			col->width = sz;
432 		return sz;
433 	case TBL_CELL_LONG:
434 	case TBL_CELL_CENTRE:
435 	case TBL_CELL_LEFT:
436 	case TBL_CELL_RIGHT:
437 		return tblcalc_literal(tbl, col, dp, mw);
438 	case TBL_CELL_NUMBER:
439 		return tblcalc_number(tbl, col, opts, dp);
440 	case TBL_CELL_DOWN:
441 		return 0;
442 	default:
443 		abort();
444 	}
445 }
446 
447 static size_t
448 tblcalc_literal(struct rofftbl *tbl, struct roffcol *col,
449     const struct tbl_dat *dp, size_t mw)
450 {
451 	const char	*str;	/* Beginning of the first line. */
452 	const char	*beg;	/* Beginning of the current line. */
453 	char		*end;	/* End of the current line. */
454 	size_t		 lsz;	/* Length of the current line. */
455 	size_t		 wsz;	/* Length of the current word. */
456 	size_t		 msz;   /* Length of the longest line. */
457 
458 	if (dp->string == NULL || *dp->string == '\0')
459 		return 0;
460 	str = mw ? mandoc_strdup(dp->string) : dp->string;
461 	msz = lsz = 0;
462 	for (beg = str; beg != NULL && *beg != '\0'; beg = end) {
463 		end = mw ? strchr(beg, ' ') : NULL;
464 		if (end != NULL) {
465 			*end++ = '\0';
466 			while (*end == ' ')
467 				end++;
468 		}
469 		wsz = (*tbl->slen)(beg, tbl->arg);
470 		if (mw && lsz && lsz + 1 + wsz <= mw)
471 			lsz += 1 + wsz;
472 		else
473 			lsz = wsz;
474 		if (msz < lsz)
475 			msz = lsz;
476 	}
477 	if (mw)
478 		free((void *)str);
479 	if (col != NULL && col->width < msz)
480 		col->width = msz;
481 	return msz;
482 }
483 
484 static size_t
485 tblcalc_number(struct rofftbl *tbl, struct roffcol *col,
486 		const struct tbl_opts *opts, const struct tbl_dat *dp)
487 {
488 	const char	*cp, *lastdigit, *lastpoint;
489 	size_t		 intsz, totsz;
490 	char		 buf[2];
491 
492 	if (dp->string == NULL || *dp->string == '\0')
493 		return 0;
494 
495 	totsz = (*tbl->slen)(dp->string, tbl->arg);
496 	if (col == NULL)
497 		return totsz;
498 
499 	/*
500 	 * Find the last digit and
501 	 * the last decimal point that is adjacent to a digit.
502 	 * The alignment indicator "\&" overrides everything.
503 	 */
504 
505 	lastdigit = lastpoint = NULL;
506 	for (cp = dp->string; cp[0] != '\0'; cp++) {
507 		if (cp[0] == '\\' && cp[1] == '&') {
508 			lastdigit = lastpoint = cp;
509 			break;
510 		} else if (cp[0] == opts->decimal &&
511 		    (isdigit((unsigned char)cp[1]) ||
512 		     (cp > dp->string && isdigit((unsigned char)cp[-1]))))
513 			lastpoint = cp;
514 		else if (isdigit((unsigned char)cp[0]))
515 			lastdigit = cp;
516 	}
517 
518 	/* Not a number, treat as a literal string. */
519 
520 	if (lastdigit == NULL) {
521 		if (col != NULL && col->width < totsz)
522 			col->width = totsz;
523 		return totsz;
524 	}
525 
526 	/* Measure the width of the integer part. */
527 
528 	if (lastpoint == NULL)
529 		lastpoint = lastdigit + 1;
530 	intsz = 0;
531 	buf[1] = '\0';
532 	for (cp = dp->string; cp < lastpoint; cp++) {
533 		buf[0] = cp[0];
534 		intsz += (*tbl->slen)(buf, tbl->arg);
535 	}
536 
537 	/*
538          * If this number has more integer digits than all numbers
539          * seen on earlier lines, shift them all to the right.
540 	 * If it has fewer, shift this number to the right.
541 	 */
542 
543 	if (intsz > col->decimal) {
544 		col->nwidth += intsz - col->decimal;
545 		col->decimal = intsz;
546 	} else
547 		totsz += col->decimal - intsz;
548 
549 	/* Update the maximum total width seen so far. */
550 
551 	if (totsz > col->nwidth)
552 		col->nwidth = totsz;
553 	if (col->nwidth > col->width)
554 		col->width = col->nwidth;
555 	return totsz;
556 }
557