1 /* $Id: term.c,v 1.214 2013/12/25 00:39:31 schwarze Exp $ */
2 /*
3 * Copyright (c) 2008, 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
4 * Copyright (c) 2010, 2011, 2012, 2013 Ingo Schwarze <schwarze@openbsd.org>
5 *
6 * Permission to use, copy, modify, and distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
9 *
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 */
18 #ifdef HAVE_CONFIG_H
19 #include "config.h"
20 #endif
21
22 #include <sys/types.h>
23
24 #include <assert.h>
25 #include <ctype.h>
26 #include <stdint.h>
27 #include <stdio.h>
28 #include <stdlib.h>
29 #include <string.h>
30
31 #include "mandoc.h"
32 #include "out.h"
33 #include "term.h"
34 #include "main.h"
35
36 static size_t cond_width(const struct termp *, int, int *);
37 static void adjbuf(struct termp *p, size_t);
38 static void bufferc(struct termp *, char);
39 static void encode(struct termp *, const char *, size_t);
40 static void encode1(struct termp *, int);
41
42 void
43 term_free(struct termp *p)
44 {
45
46 if (p->buf)
47 free(p->buf);
48 if (p->symtab)
49 mchars_free(p->symtab);
50
51 free(p);
52 }
53
54
55 void
56 term_begin(struct termp *p, term_margin head,
57 term_margin foot, const void *arg)
58 {
59
60 p->headf = head;
61 p->footf = foot;
62 p->argf = arg;
63 (*p->begin)(p);
64 }
65
66
67 void
68 term_end(struct termp *p)
69 {
70
71 (*p->end)(p);
72 }
73
74 /*
75 * Flush a line of text. A "line" is loosely defined as being something
76 * that should be followed by a newline, regardless of whether it's
77 * broken apart by newlines getting there. A line can also be a
78 * fragment of a columnar list (`Bl -tag' or `Bl -column'), which does
79 * not have a trailing newline.
80 *
81 * The following flags may be specified:
82 *
83 * - TERMP_NOBREAK: this is the most important and is used when making
84 * columns. In short: don't print a newline and instead expect the
85 * next call to do the padding up to the start of the next column.
86 * p->trailspace may be set to 0, 1, or 2, depending on how many
87 * space characters are required at the end of the column.
88 *
89 * - TERMP_DANGLE: don't newline when TERMP_NOBREAK is specified and
90 * the line is overrun, and don't pad-right if it's underrun.
91 *
92 * - TERMP_HANG: like TERMP_DANGLE, but doesn't newline when
93 * overrunning, instead save the position and continue at that point
94 * when the next invocation.
95 *
96 * In-line line breaking:
97 *
98 * If TERMP_NOBREAK is specified and the line overruns the right
99 * margin, it will break and pad-right to the right margin after
100 * writing. If maxrmargin is violated, it will break and continue
101 * writing from the right-margin, which will lead to the above scenario
102 * upon exit. Otherwise, the line will break at the right margin.
103 */
104 void
105 term_flushln(struct termp *p)
106 {
107 size_t i; /* current input position in p->buf */
108 int ntab; /* number of tabs to prepend */
109 size_t vis; /* current visual position on output */
110 size_t vbl; /* number of blanks to prepend to output */
111 size_t vend; /* end of word visual position on output */
112 size_t bp; /* visual right border position */
113 size_t dv; /* temporary for visual pos calculations */
114 size_t j; /* temporary loop index for p->buf */
115 size_t jhy; /* last hyph before overflow w/r/t j */
116 size_t maxvis; /* output position of visible boundary */
117 size_t mmax; /* used in calculating bp */
118
119 /*
120 * First, establish the maximum columns of "visible" content.
121 * This is usually the difference between the right-margin and
122 * an indentation, but can be, for tagged lists or columns, a
123 * small set of values.
124 *
125 * The following unsigned-signed subtractions look strange,
126 * but they are actually correct. If the int p->overstep
127 * is negative, it gets sign extended. Subtracting that
128 * very large size_t effectively adds a small number to dv.
129 */
130 assert (p->rmargin >= p->offset);
131 dv = p->rmargin - p->offset;
132 maxvis = (int)dv > p->overstep ? dv - (size_t)p->overstep : 0;
133 dv = p->maxrmargin - p->offset;
134 mmax = (int)dv > p->overstep ? dv - (size_t)p->overstep : 0;
135
136 bp = TERMP_NOBREAK & p->flags ? mmax : maxvis;
137
138 /*
139 * Calculate the required amount of padding.
140 */
141 vbl = p->offset + p->overstep > p->viscol ?
142 p->offset + p->overstep - p->viscol : 0;
143
144 vis = vend = 0;
145 i = 0;
146
147 while (i < p->col) {
148 /*
149 * Handle literal tab characters: collapse all
150 * subsequent tabs into a single huge set of spaces.
151 */
152 ntab = 0;
153 while (i < p->col && '\t' == p->buf[i]) {
154 vend = (vis / p->tabwidth + 1) * p->tabwidth;
155 vbl += vend - vis;
156 vis = vend;
157 ntab++;
158 i++;
159 }
160
161 /*
162 * Count up visible word characters. Control sequences
163 * (starting with the CSI) aren't counted. A space
164 * generates a non-printing word, which is valid (the
165 * space is printed according to regular spacing rules).
166 */
167
168 for (j = i, jhy = 0; j < p->col; j++) {
169 if (' ' == p->buf[j] || '\t' == p->buf[j])
170 break;
171
172 /* Back over the the last printed character. */
173 if (8 == p->buf[j]) {
174 assert(j);
175 vend -= (*p->width)(p, p->buf[j - 1]);
176 continue;
177 }
178
179 /* Regular word. */
180 /* Break at the hyphen point if we overrun. */
181 if (vend > vis && vend < bp &&
182 ASCII_HYPH == p->buf[j])
183 jhy = j;
184
185 vend += (*p->width)(p, p->buf[j]);
186 }
187
188 /*
189 * Find out whether we would exceed the right margin.
190 * If so, break to the next line.
191 */
192 if (vend > bp && 0 == jhy && vis > 0) {
193 vend -= vis;
194 (*p->endline)(p);
195 p->viscol = 0;
196 if (TERMP_NOBREAK & p->flags) {
197 vbl = p->rmargin;
198 vend += p->rmargin - p->offset;
199 } else
200 vbl = p->offset;
201
202 /* use pending tabs on the new line */
203
204 if (0 < ntab)
205 vbl += ntab * p->tabwidth;
206
207 /*
208 * Remove the p->overstep width.
209 * Again, if p->overstep is negative,
210 * sign extension does the right thing.
211 */
212
213 bp += (size_t)p->overstep;
214 p->overstep = 0;
215 }
216
217 /* Write out the [remaining] word. */
218 for ( ; i < p->col; i++) {
219 if (vend > bp && jhy > 0 && i > jhy)
220 break;
221 if ('\t' == p->buf[i])
222 break;
223 if (' ' == p->buf[i]) {
224 j = i;
225 while (' ' == p->buf[i])
226 i++;
227 dv = (i - j) * (*p->width)(p, ' ');
228 vbl += dv;
229 vend += dv;
230 break;
231 }
232 if (ASCII_NBRSP == p->buf[i]) {
233 vbl += (*p->width)(p, ' ');
234 continue;
235 }
236
237 /*
238 * Now we definitely know there will be
239 * printable characters to output,
240 * so write preceding white space now.
241 */
242 if (vbl) {
243 (*p->advance)(p, vbl);
244 p->viscol += vbl;
245 vbl = 0;
246 }
247
248 if (ASCII_HYPH == p->buf[i]) {
249 (*p->letter)(p, '-');
250 p->viscol += (*p->width)(p, '-');
251 continue;
252 }
253
254 (*p->letter)(p, p->buf[i]);
255 if (8 == p->buf[i])
256 p->viscol -= (*p->width)(p, p->buf[i-1]);
257 else
258 p->viscol += (*p->width)(p, p->buf[i]);
259 }
260 vis = vend;
261 }
262
263 /*
264 * If there was trailing white space, it was not printed;
265 * so reset the cursor position accordingly.
266 */
267 if (vis)
268 vis -= vbl;
269
270 p->col = 0;
271 p->overstep = 0;
272
273 if ( ! (TERMP_NOBREAK & p->flags)) {
274 p->viscol = 0;
275 (*p->endline)(p);
276 return;
277 }
278
279 if (TERMP_HANG & p->flags) {
280 p->overstep = (int)(vis - maxvis +
281 p->trailspace * (*p->width)(p, ' '));
282
283 /*
284 * If we have overstepped the margin, temporarily move
285 * it to the right and flag the rest of the line to be
286 * shorter.
287 * If there is a request to keep the columns together,
288 * allow negative overstep when the column is not full.
289 */
290 if (p->trailspace && p->overstep < 0)
291 p->overstep = 0;
292 return;
293
294 } else if (TERMP_DANGLE & p->flags)
295 return;
296
297 /* If the column was overrun, break the line. */
298 if (maxvis < vis + p->trailspace * (*p->width)(p, ' ')) {
299 (*p->endline)(p);
300 p->viscol = 0;
301 }
302 }
303
304
305 /*
306 * A newline only breaks an existing line; it won't assert vertical
307 * space. All data in the output buffer is flushed prior to the newline
308 * assertion.
309 */
310 void
311 term_newln(struct termp *p)
312 {
313
314 p->flags |= TERMP_NOSPACE;
315 if (p->col || p->viscol)
316 term_flushln(p);
317 }
318
319
320 /*
321 * Asserts a vertical space (a full, empty line-break between lines).
322 * Note that if used twice, this will cause two blank spaces and so on.
323 * All data in the output buffer is flushed prior to the newline
324 * assertion.
325 */
326 void
327 term_vspace(struct termp *p)
328 {
329
330 term_newln(p);
331 p->viscol = 0;
332 if (0 < p->skipvsp)
333 p->skipvsp--;
334 else
335 (*p->endline)(p);
336 }
337
338 void
339 term_fontlast(struct termp *p)
340 {
341 enum termfont f;
342
343 f = p->fontl;
344 p->fontl = p->fontq[p->fonti];
345 p->fontq[p->fonti] = f;
346 }
347
348
349 void
350 term_fontrepl(struct termp *p, enum termfont f)
351 {
352
353 p->fontl = p->fontq[p->fonti];
354 p->fontq[p->fonti] = f;
355 }
356
357
358 void
359 term_fontpush(struct termp *p, enum termfont f)
360 {
361
362 assert(p->fonti + 1 < 10);
363 p->fontl = p->fontq[p->fonti];
364 p->fontq[++p->fonti] = f;
365 }
366
367
368 const void *
369 term_fontq(struct termp *p)
370 {
371
372 return(&p->fontq[p->fonti]);
373 }
374
375
376 enum termfont
377 term_fonttop(struct termp *p)
378 {
379
380 return(p->fontq[p->fonti]);
381 }
382
383
384 void
385 term_fontpopq(struct termp *p, const void *key)
386 {
387
388 while (p->fonti >= 0 && key < (void *)(p->fontq + p->fonti))
389 p->fonti--;
390 assert(p->fonti >= 0);
391 }
392
393
394 void
395 term_fontpop(struct termp *p)
396 {
397
398 assert(p->fonti);
399 p->fonti--;
400 }
401
402 /*
403 * Handle pwords, partial words, which may be either a single word or a
404 * phrase that cannot be broken down (such as a literal string). This
405 * handles word styling.
406 */
407 void
408 term_word(struct termp *p, const char *word)
409 {
410 const char nbrsp[2] = { ASCII_NBRSP, 0 };
411 const char *seq, *cp;
412 char c;
413 int sz, uc;
414 size_t ssz;
415 enum mandoc_esc esc;
416
417 if ( ! (TERMP_NOSPACE & p->flags)) {
418 if ( ! (TERMP_KEEP & p->flags)) {
419 bufferc(p, ' ');
420 if (TERMP_SENTENCE & p->flags)
421 bufferc(p, ' ');
422 } else
423 bufferc(p, ASCII_NBRSP);
424 }
425 if (TERMP_PREKEEP & p->flags)
426 p->flags |= TERMP_KEEP;
427
428 if ( ! (p->flags & TERMP_NONOSPACE))
429 p->flags &= ~TERMP_NOSPACE;
430 else
431 p->flags |= TERMP_NOSPACE;
432
433 p->flags &= ~TERMP_SENTENCE;
434
435 while ('\0' != *word) {
436 if ('\\' != *word) {
437 if (TERMP_SKIPCHAR & p->flags) {
438 p->flags &= ~TERMP_SKIPCHAR;
439 word++;
440 continue;
441 }
442 if (TERMP_NBRWORD & p->flags) {
443 if (' ' == *word) {
444 encode(p, nbrsp, 1);
445 word++;
446 continue;
447 }
448 ssz = strcspn(word, "\\ ");
449 } else
450 ssz = strcspn(word, "\\");
451 encode(p, word, ssz);
452 word += (int)ssz;
453 continue;
454 }
455
456 word++;
457 esc = mandoc_escape(&word, &seq, &sz);
458 if (ESCAPE_ERROR == esc)
459 break;
460
461 if (TERMENC_ASCII != p->enc)
462 switch (esc) {
463 case (ESCAPE_UNICODE):
464 uc = mchars_num2uc(seq + 1, sz - 1);
465 if ('\0' == uc)
466 break;
467 encode1(p, uc);
468 continue;
469 case (ESCAPE_SPECIAL):
470 uc = mchars_spec2cp(p->symtab, seq, sz);
471 if (uc <= 0)
472 break;
473 encode1(p, uc);
474 continue;
475 default:
476 break;
477 }
478
479 switch (esc) {
480 case (ESCAPE_UNICODE):
481 encode1(p, '?');
482 break;
483 case (ESCAPE_NUMBERED):
484 c = mchars_num2char(seq, sz);
485 if ('\0' != c)
486 encode(p, &c, 1);
487 break;
488 case (ESCAPE_SPECIAL):
489 cp = mchars_spec2str(p->symtab, seq, sz, &ssz);
490 if (NULL != cp)
491 encode(p, cp, ssz);
492 else if (1 == ssz)
493 encode(p, seq, sz);
494 break;
495 case (ESCAPE_FONTBOLD):
496 term_fontrepl(p, TERMFONT_BOLD);
497 break;
498 case (ESCAPE_FONTITALIC):
499 term_fontrepl(p, TERMFONT_UNDER);
500 break;
501 case (ESCAPE_FONTBI):
502 term_fontrepl(p, TERMFONT_BI);
503 break;
504 case (ESCAPE_FONT):
505 /* FALLTHROUGH */
506 case (ESCAPE_FONTROMAN):
507 term_fontrepl(p, TERMFONT_NONE);
508 break;
509 case (ESCAPE_FONTPREV):
510 term_fontlast(p);
511 break;
512 case (ESCAPE_NOSPACE):
513 if (TERMP_SKIPCHAR & p->flags)
514 p->flags &= ~TERMP_SKIPCHAR;
515 else if ('\0' == *word)
516 p->flags |= TERMP_NOSPACE;
517 break;
518 case (ESCAPE_SKIPCHAR):
519 p->flags |= TERMP_SKIPCHAR;
520 break;
521 default:
522 break;
523 }
524 }
525 p->flags &= ~TERMP_NBRWORD;
526 }
527
528 static void
529 adjbuf(struct termp *p, size_t sz)
530 {
531
532 if (0 == p->maxcols)
533 p->maxcols = 1024;
534 while (sz >= p->maxcols)
535 p->maxcols <<= 2;
536
537 p->buf = mandoc_realloc(p->buf, sizeof(int) * p->maxcols);
538 }
539
540 static void
541 bufferc(struct termp *p, char c)
542 {
543
544 if (p->col + 1 >= p->maxcols)
545 adjbuf(p, p->col + 1);
546
547 p->buf[p->col++] = c;
548 }
549
550 /*
551 * See encode().
552 * Do this for a single (probably unicode) value.
553 * Does not check for non-decorated glyphs.
554 */
555 static void
556 encode1(struct termp *p, int c)
557 {
558 enum termfont f;
559
560 if (TERMP_SKIPCHAR & p->flags) {
561 p->flags &= ~TERMP_SKIPCHAR;
562 return;
563 }
564
565 if (p->col + 6 >= p->maxcols)
566 adjbuf(p, p->col + 6);
567
568 f = term_fonttop(p);
569
570 if (TERMFONT_UNDER == f || TERMFONT_BI == f) {
571 p->buf[p->col++] = '_';
572 p->buf[p->col++] = 8;
573 }
574 if (TERMFONT_BOLD == f || TERMFONT_BI == f) {
575 if (ASCII_HYPH == c)
576 p->buf[p->col++] = '-';
577 else
578 p->buf[p->col++] = c;
579 p->buf[p->col++] = 8;
580 }
581 p->buf[p->col++] = c;
582 }
583
584 static void
585 encode(struct termp *p, const char *word, size_t sz)
586 {
587 size_t i;
588
589 if (TERMP_SKIPCHAR & p->flags) {
590 p->flags &= ~TERMP_SKIPCHAR;
591 return;
592 }
593
594 /*
595 * Encode and buffer a string of characters. If the current
596 * font mode is unset, buffer directly, else encode then buffer
597 * character by character.
598 */
599
600 if (TERMFONT_NONE == term_fonttop(p)) {
601 if (p->col + sz >= p->maxcols)
602 adjbuf(p, p->col + sz);
603 for (i = 0; i < sz; i++)
604 p->buf[p->col++] = word[i];
605 return;
606 }
607
608 /* Pre-buffer, assuming worst-case. */
609
610 if (p->col + 1 + (sz * 5) >= p->maxcols)
611 adjbuf(p, p->col + 1 + (sz * 5));
612
613 for (i = 0; i < sz; i++) {
614 if (ASCII_HYPH == word[i] ||
615 isgraph((unsigned char)word[i]))
616 encode1(p, word[i]);
617 else
618 p->buf[p->col++] = word[i];
619 }
620 }
621
622 size_t
623 term_len(const struct termp *p, size_t sz)
624 {
625
626 return((*p->width)(p, ' ') * sz);
627 }
628
629 static size_t
630 cond_width(const struct termp *p, int c, int *skip)
631 {
632
633 if (*skip) {
634 (*skip) = 0;
635 return(0);
636 } else
637 return((*p->width)(p, c));
638 }
639
640 size_t
641 term_strlen(const struct termp *p, const char *cp)
642 {
643 size_t sz, rsz, i;
644 int ssz, skip, c;
645 const char *seq, *rhs;
646 enum mandoc_esc esc;
647 static const char rej[] = { '\\', ASCII_HYPH, ASCII_NBRSP, '\0' };
648
649 /*
650 * Account for escaped sequences within string length
651 * calculations. This follows the logic in term_word() as we
652 * must calculate the width of produced strings.
653 */
654
655 sz = 0;
656 skip = 0;
657 while ('\0' != *cp) {
658 rsz = strcspn(cp, rej);
659 for (i = 0; i < rsz; i++)
660 sz += cond_width(p, *cp++, &skip);
661
662 c = 0;
663 switch (*cp) {
664 case ('\\'):
665 cp++;
666 esc = mandoc_escape(&cp, &seq, &ssz);
667 if (ESCAPE_ERROR == esc)
668 return(sz);
669
670 if (TERMENC_ASCII != p->enc)
671 switch (esc) {
672 case (ESCAPE_UNICODE):
673 c = mchars_num2uc
674 (seq + 1, ssz - 1);
675 if ('\0' == c)
676 break;
677 sz += cond_width(p, c, &skip);
678 continue;
679 case (ESCAPE_SPECIAL):
680 c = mchars_spec2cp
681 (p->symtab, seq, ssz);
682 if (c <= 0)
683 break;
684 sz += cond_width(p, c, &skip);
685 continue;
686 default:
687 break;
688 }
689
690 rhs = NULL;
691
692 switch (esc) {
693 case (ESCAPE_UNICODE):
694 sz += cond_width(p, '?', &skip);
695 break;
696 case (ESCAPE_NUMBERED):
697 c = mchars_num2char(seq, ssz);
698 if ('\0' != c)
699 sz += cond_width(p, c, &skip);
700 break;
701 case (ESCAPE_SPECIAL):
702 rhs = mchars_spec2str
703 (p->symtab, seq, ssz, &rsz);
704
705 if (ssz != 1 || rhs)
706 break;
707
708 rhs = seq;
709 rsz = ssz;
710 break;
711 case (ESCAPE_SKIPCHAR):
712 skip = 1;
713 break;
714 default:
715 break;
716 }
717
718 if (NULL == rhs)
719 break;
720
721 if (skip) {
722 skip = 0;
723 break;
724 }
725
726 for (i = 0; i < rsz; i++)
727 sz += (*p->width)(p, *rhs++);
728 break;
729 case (ASCII_NBRSP):
730 sz += cond_width(p, ' ', &skip);
731 cp++;
732 break;
733 case (ASCII_HYPH):
734 sz += cond_width(p, '-', &skip);
735 cp++;
736 break;
737 default:
738 break;
739 }
740 }
741
742 return(sz);
743 }
744
745 /* ARGSUSED */
746 size_t
747 term_vspan(const struct termp *p, const struct roffsu *su)
748 {
749 double r;
750
751 switch (su->unit) {
752 case (SCALE_CM):
753 r = su->scale * 2;
754 break;
755 case (SCALE_IN):
756 r = su->scale * 6;
757 break;
758 case (SCALE_PC):
759 r = su->scale;
760 break;
761 case (SCALE_PT):
762 r = su->scale / 8;
763 break;
764 case (SCALE_MM):
765 r = su->scale / 1000;
766 break;
767 case (SCALE_VS):
768 r = su->scale;
769 break;
770 default:
771 r = su->scale - 1;
772 break;
773 }
774
775 if (r < 0.0)
776 r = 0.0;
777 return(/* LINTED */(size_t)
778 r);
779 }
780
781 size_t
782 term_hspan(const struct termp *p, const struct roffsu *su)
783 {
784 double v;
785
786 v = ((*p->hspan)(p, su));
787 if (v < 0.0)
788 v = 0.0;
789 return((size_t) /* LINTED */
790 v);
791 }