xref: /openbsd-src/usr.bin/mandoc/out.c (revision a2d98599e3c69439489c0bfafa67f0ebef23661b)
1 /*	$OpenBSD: out.c,v 1.54 2021/09/07 17:05:30 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			 ewidth, min1, min2, wanted, width, xwidth;
125 	int			 done, icol, maxcol, necol, nxcol, quirkcol;
126 
127 	/*
128 	 * Allocate the master column specifiers.  These will hold the
129 	 * widths and decimal positions for all cells in the column.  It
130 	 * must be freed and nullified by the caller.
131 	 */
132 
133 	assert(tbl->cols == NULL);
134 	tbl->cols = mandoc_calloc((size_t)sp_first->opts->cols,
135 	    sizeof(struct roffcol));
136 	opts = sp_first->opts;
137 
138 	maxcol = -1;
139 	first_group = NULL;
140 	for (sp = sp_first; sp != NULL; sp = sp->next) {
141 		if (sp->pos != TBL_SPAN_DATA)
142 			continue;
143 
144 		/*
145 		 * Account for the data cells in the layout, matching it
146 		 * to data cells in the data section.
147 		 */
148 
149 		gp = &first_group;
150 		for (dp = sp->first; dp != NULL; dp = dp->next) {
151 			icol = dp->layout->col;
152 			while (maxcol < icol + dp->hspans)
153 				tbl->cols[++maxcol].spacing = SIZE_MAX;
154 			col = tbl->cols + icol;
155 			col->flags |= dp->layout->flags;
156 			if (dp->layout->flags & TBL_CELL_WIGN)
157 				continue;
158 
159 			/* Handle explicit width specifications. */
160 
161 			if (dp->layout->wstr != NULL &&
162 			    dp->layout->width == 0 &&
163 			    a2roffsu(dp->layout->wstr, &su, SCALE_EN)
164 			    != NULL)
165 				dp->layout->width =
166 				    (*tbl->sulen)(&su, tbl->arg);
167 			if (col->width < dp->layout->width)
168 				col->width = dp->layout->width;
169 			if (dp->layout->spacing != SIZE_MAX &&
170 			    (col->spacing == SIZE_MAX ||
171 			     col->spacing < dp->layout->spacing))
172 				col->spacing = dp->layout->spacing;
173 
174 			/*
175 			 * Calculate an automatic width.
176 			 * Except for spanning cells, apply it.
177 			 */
178 
179 			width = tblcalc_data(tbl,
180 			    dp->hspans == 0 ? col : NULL,
181 			    opts, dp,
182 			    dp->block == 0 ? 0 :
183 			    dp->layout->width ? dp->layout->width :
184 			    rmargin ? (rmargin + sp->opts->cols / 2)
185 			    / (sp->opts->cols + 1) : 0);
186 			if (dp->hspans == 0)
187 				continue;
188 
189 			/*
190 			 * Build an ordered, singly linked list
191 			 * of all groups of columns joined by spans,
192 			 * recording the minimum width for each group.
193 			 */
194 
195 			while (*gp != NULL && ((*gp)->startcol < icol ||
196 			    (*gp)->endcol < icol + dp->hspans))
197 				gp = &(*gp)->next;
198 			if (*gp == NULL || (*gp)->startcol > icol ||
199                             (*gp)->endcol > icol + dp->hspans) {
200 				g = mandoc_malloc(sizeof(*g));
201 				g->next = *gp;
202 				g->wanted = width;
203 				g->startcol = icol;
204 				g->endcol = icol + dp->hspans;
205 				*gp = g;
206 			} else if ((*gp)->wanted < width)
207 				(*gp)->wanted = width;
208 		}
209 	}
210 
211 	/*
212 	 * The minimum width of columns explicitly specified
213 	 * in the layout is 1n.
214 	 */
215 
216 	if (maxcol < sp_first->opts->cols - 1)
217 		maxcol = sp_first->opts->cols - 1;
218 	for (icol = 0; icol <= maxcol; icol++) {
219 		col = tbl->cols + icol;
220 		if (col->width < 1)
221 			col->width = 1;
222 
223 		/*
224 		 * Column spacings are needed for span width
225 		 * calculations, so set the default values now.
226 		 */
227 
228 		if (col->spacing == SIZE_MAX || icol == maxcol)
229 			col->spacing = 3;
230 	}
231 
232 	/*
233 	 * Replace the minimum widths with the missing widths,
234 	 * and dismiss groups that are already wide enough.
235 	 */
236 
237 	gp = &first_group;
238 	while ((g = *gp) != NULL) {
239 		done = 0;
240 		for (icol = g->startcol; icol <= g->endcol; icol++) {
241 			width = tbl->cols[icol].width;
242 			if (icol < g->endcol)
243 				width += tbl->cols[icol].spacing;
244 			if (g->wanted <= width) {
245 				done = 1;
246 				break;
247 			} else
248 				(*gp)->wanted -= width;
249 		}
250 		if (done) {
251 			*gp = g->next;
252 			free(g);
253 		} else
254 			gp = &(*gp)->next;
255 	}
256 
257 	while (first_group != NULL) {
258 
259 		/*
260 		 * Find the smallest and second smallest column width
261 		 * among the columns which may need expamsion.
262 		 */
263 
264 		min1 = min2 = SIZE_MAX;
265 		for (icol = 0; icol <= maxcol; icol++) {
266 			width = tbl->cols[icol].width;
267 			if (min1 > width) {
268 				min2 = min1;
269 				min1 = width;
270 			} else if (min1 < width && min2 > width)
271 				min2 = width;
272 		}
273 
274 		/*
275 		 * Find the minimum wanted width
276 		 * for any one of the narrowest columns,
277 		 * and mark the columns wanting that width.
278 		 */
279 
280 		wanted = min2;
281 		for (g = first_group; g != NULL; g = g->next) {
282 			necol = 0;
283 			for (icol = g->startcol; icol <= g->endcol; icol++)
284 				if (tbl->cols[icol].width == min1)
285 					necol++;
286 			if (necol == 0)
287 				continue;
288 			width = min1 + (g->wanted - 1) / necol + 1;
289 			if (width > min2)
290 				width = min2;
291 			if (wanted > width)
292 				wanted = width;
293 		}
294 
295 		/* Record the effect of the widening. */
296 
297 		gp = &first_group;
298 		while ((g = *gp) != NULL) {
299 			done = 0;
300 			for (icol = g->startcol; icol <= g->endcol; icol++) {
301 				if (tbl->cols[icol].width != min1)
302 					continue;
303 				if (g->wanted <= wanted - min1) {
304 					tbl->cols[icol].width += g->wanted;
305 					done = 1;
306 					break;
307 				}
308 				tbl->cols[icol].width = wanted;
309 				g->wanted -= wanted - min1;
310 			}
311 			if (done) {
312 				*gp = g->next;
313 				free(g);
314 			} else
315 				gp = &(*gp)->next;
316 		}
317 	}
318 
319 	/*
320 	 * Align numbers with text.
321 	 * Count columns to equalize and columns to maximize.
322 	 * Find maximum width of the columns to equalize.
323 	 * Find total width of the columns *not* to maximize.
324 	 */
325 
326 	necol = nxcol = 0;
327 	ewidth = xwidth = 0;
328 	for (icol = 0; icol <= maxcol; icol++) {
329 		col = tbl->cols + icol;
330 		if (col->width > col->nwidth)
331 			col->decimal += (col->width - col->nwidth) / 2;
332 		if (col->flags & TBL_CELL_EQUAL) {
333 			necol++;
334 			if (ewidth < col->width)
335 				ewidth = col->width;
336 		}
337 		if (col->flags & TBL_CELL_WMAX)
338 			nxcol++;
339 		else
340 			xwidth += col->width;
341 	}
342 
343 	/*
344 	 * Equalize columns, if requested for any of them.
345 	 * Update total width of the columns not to maximize.
346 	 */
347 
348 	if (necol) {
349 		for (icol = 0; icol <= maxcol; icol++) {
350 			col = tbl->cols + icol;
351 			if ( ! (col->flags & TBL_CELL_EQUAL))
352 				continue;
353 			if (col->width == ewidth)
354 				continue;
355 			if (nxcol && rmargin)
356 				xwidth += ewidth - col->width;
357 			col->width = ewidth;
358 		}
359 	}
360 
361 	/*
362 	 * If there are any columns to maximize, find the total
363 	 * available width, deducting 3n margins between columns.
364 	 * Distribute the available width evenly.
365 	 */
366 
367 	if (nxcol && rmargin) {
368 		xwidth += 3*maxcol +
369 		    (opts->opts & (TBL_OPT_BOX | TBL_OPT_DBOX) ?
370 		     2 : !!opts->lvert + !!opts->rvert);
371 		if (rmargin <= offset + xwidth)
372 			return;
373 		xwidth = rmargin - offset - xwidth;
374 
375 		/*
376 		 * Emulate a bug in GNU tbl width calculation that
377 		 * manifests itself for large numbers of x-columns.
378 		 * Emulating it for 5 x-columns gives identical
379 		 * behaviour for up to 6 x-columns.
380 		 */
381 
382 		if (nxcol == 5) {
383 			quirkcol = xwidth % nxcol + 2;
384 			if (quirkcol != 3 && quirkcol != 4)
385 				quirkcol = -1;
386 		} else
387 			quirkcol = -1;
388 
389 		necol = 0;
390 		ewidth = 0;
391 		for (icol = 0; icol <= maxcol; icol++) {
392 			col = tbl->cols + icol;
393 			if ( ! (col->flags & TBL_CELL_WMAX))
394 				continue;
395 			col->width = (double)xwidth * ++necol / nxcol
396 			    - ewidth + 0.4995;
397 			if (necol == quirkcol)
398 				col->width--;
399 			ewidth += col->width;
400 		}
401 	}
402 }
403 
404 static size_t
405 tblcalc_data(struct rofftbl *tbl, struct roffcol *col,
406     const struct tbl_opts *opts, const struct tbl_dat *dp, size_t mw)
407 {
408 	size_t		 sz;
409 
410 	/* Branch down into data sub-types. */
411 
412 	switch (dp->layout->pos) {
413 	case TBL_CELL_HORIZ:
414 	case TBL_CELL_DHORIZ:
415 		sz = (*tbl->len)(1, tbl->arg);
416 		if (col != NULL && col->width < sz)
417 			col->width = sz;
418 		return sz;
419 	case TBL_CELL_LONG:
420 	case TBL_CELL_CENTRE:
421 	case TBL_CELL_LEFT:
422 	case TBL_CELL_RIGHT:
423 		return tblcalc_literal(tbl, col, dp, mw);
424 	case TBL_CELL_NUMBER:
425 		return tblcalc_number(tbl, col, opts, dp);
426 	case TBL_CELL_DOWN:
427 		return 0;
428 	default:
429 		abort();
430 	}
431 }
432 
433 static size_t
434 tblcalc_literal(struct rofftbl *tbl, struct roffcol *col,
435     const struct tbl_dat *dp, size_t mw)
436 {
437 	const char	*str;	/* Beginning of the first line. */
438 	const char	*beg;	/* Beginning of the current line. */
439 	char		*end;	/* End of the current line. */
440 	size_t		 lsz;	/* Length of the current line. */
441 	size_t		 wsz;	/* Length of the current word. */
442 	size_t		 msz;   /* Length of the longest line. */
443 
444 	if (dp->string == NULL || *dp->string == '\0')
445 		return 0;
446 	str = mw ? mandoc_strdup(dp->string) : dp->string;
447 	msz = lsz = 0;
448 	for (beg = str; beg != NULL && *beg != '\0'; beg = end) {
449 		end = mw ? strchr(beg, ' ') : NULL;
450 		if (end != NULL) {
451 			*end++ = '\0';
452 			while (*end == ' ')
453 				end++;
454 		}
455 		wsz = (*tbl->slen)(beg, tbl->arg);
456 		if (mw && lsz && lsz + 1 + wsz <= mw)
457 			lsz += 1 + wsz;
458 		else
459 			lsz = wsz;
460 		if (msz < lsz)
461 			msz = lsz;
462 	}
463 	if (mw)
464 		free((void *)str);
465 	if (col != NULL && col->width < msz)
466 		col->width = msz;
467 	return msz;
468 }
469 
470 static size_t
471 tblcalc_number(struct rofftbl *tbl, struct roffcol *col,
472 		const struct tbl_opts *opts, const struct tbl_dat *dp)
473 {
474 	const char	*cp, *lastdigit, *lastpoint;
475 	size_t		 intsz, totsz;
476 	char		 buf[2];
477 
478 	if (dp->string == NULL || *dp->string == '\0')
479 		return 0;
480 
481 	totsz = (*tbl->slen)(dp->string, tbl->arg);
482 	if (col == NULL)
483 		return totsz;
484 
485 	/*
486 	 * Find the last digit and
487 	 * the last decimal point that is adjacent to a digit.
488 	 * The alignment indicator "\&" overrides everything.
489 	 */
490 
491 	lastdigit = lastpoint = NULL;
492 	for (cp = dp->string; cp[0] != '\0'; cp++) {
493 		if (cp[0] == '\\' && cp[1] == '&') {
494 			lastdigit = lastpoint = cp;
495 			break;
496 		} else if (cp[0] == opts->decimal &&
497 		    (isdigit((unsigned char)cp[1]) ||
498 		     (cp > dp->string && isdigit((unsigned char)cp[-1]))))
499 			lastpoint = cp;
500 		else if (isdigit((unsigned char)cp[0]))
501 			lastdigit = cp;
502 	}
503 
504 	/* Not a number, treat as a literal string. */
505 
506 	if (lastdigit == NULL) {
507 		if (col != NULL && col->width < totsz)
508 			col->width = totsz;
509 		return totsz;
510 	}
511 
512 	/* Measure the width of the integer part. */
513 
514 	if (lastpoint == NULL)
515 		lastpoint = lastdigit + 1;
516 	intsz = 0;
517 	buf[1] = '\0';
518 	for (cp = dp->string; cp < lastpoint; cp++) {
519 		buf[0] = cp[0];
520 		intsz += (*tbl->slen)(buf, tbl->arg);
521 	}
522 
523 	/*
524          * If this number has more integer digits than all numbers
525          * seen on earlier lines, shift them all to the right.
526 	 * If it has fewer, shift this number to the right.
527 	 */
528 
529 	if (intsz > col->decimal) {
530 		col->nwidth += intsz - col->decimal;
531 		col->decimal = intsz;
532 	} else
533 		totsz += col->decimal - intsz;
534 
535 	/* Update the maximum total width seen so far. */
536 
537 	if (totsz > col->nwidth)
538 		col->nwidth = totsz;
539 	if (col->nwidth > col->width)
540 		col->width = col->nwidth;
541 	return totsz;
542 }
543