1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1990, 1993, 1994
5 * The Regents of the University of California. All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Michael Rendell of the Memorial University of Newfoundland.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35 #ifndef lint
36 static const char copyright[] =
37 "@(#) Copyright (c) 1990, 1993, 1994\n\
38 The Regents of the University of California. All rights reserved.\n";
39 #endif
40
41 #if 0
42 #ifndef lint
43 static char sccsid[] = "@(#)col.c 8.5 (Berkeley) 5/4/95";
44 #endif
45 #endif
46
47 #include <sys/cdefs.h>
48 #include <sys/capsicum.h>
49
50 #include <capsicum_helpers.h>
51 #include <err.h>
52 #include <errno.h>
53 #include <locale.h>
54 #include <stdio.h>
55 #include <stdlib.h>
56 #include <string.h>
57 #include <termios.h>
58 #include <unistd.h>
59 #include <wchar.h>
60 #include <wctype.h>
61
62 #define BS '\b' /* backspace */
63 #define TAB '\t' /* tab */
64 #define SPACE ' ' /* space */
65 #define NL '\n' /* newline */
66 #define CR '\r' /* carriage return */
67 #define ESC '\033' /* escape */
68 #define SI '\017' /* shift in to normal character set */
69 #define SO '\016' /* shift out to alternate character set */
70 #define VT '\013' /* vertical tab (aka reverse line feed) */
71 #define RLF '7' /* ESC-7 reverse line feed */
72 #define RHLF '8' /* ESC-8 reverse half-line feed */
73 #define FHLF '9' /* ESC-9 forward half-line feed */
74
75 /* build up at least this many lines before flushing them out */
76 #define BUFFER_MARGIN 32
77
78 typedef char CSET;
79
80 typedef struct char_str {
81 #define CS_NORMAL 1
82 #define CS_ALTERNATE 2
83 short c_column; /* column character is in */
84 CSET c_set; /* character set (currently only 2) */
85 wchar_t c_char; /* character in question */
86 int c_width; /* character width */
87 } CHAR;
88
89 typedef struct line_str LINE;
90 struct line_str {
91 CHAR *l_line; /* characters on the line */
92 LINE *l_prev; /* previous line */
93 LINE *l_next; /* next line */
94 int l_lsize; /* allocated sizeof l_line */
95 int l_line_len; /* strlen(l_line) */
96 int l_needs_sort; /* set if chars went in out of order */
97 int l_max_col; /* max column in the line */
98 };
99
100 static void addto_lineno(int *, int);
101 static LINE *alloc_line(void);
102 static void dowarn(int);
103 static void flush_line(LINE *);
104 static void flush_lines(int);
105 static void flush_blanks(void);
106 static void free_line(LINE *);
107 static void usage(void);
108
109 static CSET last_set; /* char_set of last char printed */
110 static LINE *lines;
111 static int compress_spaces; /* if doing space -> tab conversion */
112 static int fine; /* if `fine' resolution (half lines) */
113 static int max_bufd_lines; /* max # of half lines to keep in memory */
114 static int nblank_lines; /* # blanks after last flushed line */
115 static int no_backspaces; /* if not to output any backspaces */
116 static int pass_unknown_seqs; /* pass unknown control sequences */
117
118 #define PUTC(ch) \
119 do { \
120 if (putwchar(ch) == WEOF) \
121 errx(1, "write error"); \
122 } while (0)
123
124 int
main(int argc,char ** argv)125 main(int argc, char **argv)
126 {
127 wint_t ch;
128 CHAR *c;
129 CSET cur_set; /* current character set */
130 LINE *l; /* current line */
131 int extra_lines; /* # of lines above first line */
132 int cur_col; /* current column */
133 int cur_line; /* line number of current position */
134 int max_line; /* max value of cur_line */
135 int this_line; /* line l points to */
136 int nflushd_lines; /* number of lines that were flushed */
137 int adjust, opt, warned, width;
138 const char *errstr;
139
140 (void)setlocale(LC_CTYPE, "");
141
142 if (caph_limit_stdio() == -1)
143 err(1, "unable to limit stdio");
144
145 if (caph_enter() < 0)
146 err(1, "unable to enter capability mode");
147
148 max_bufd_lines = 256;
149 compress_spaces = 1; /* compress spaces into tabs */
150 while ((opt = getopt(argc, argv, "bfhl:px")) != -1)
151 switch (opt) {
152 case 'b': /* do not output backspaces */
153 no_backspaces = 1;
154 break;
155 case 'f': /* allow half forward line feeds */
156 fine = 1;
157 break;
158 case 'h': /* compress spaces into tabs */
159 compress_spaces = 1;
160 break;
161 case 'l': /* buffered line count */
162 max_bufd_lines = strtonum(optarg, 1,
163 (INT_MAX - BUFFER_MARGIN) / 2, &errstr) * 2;
164 if (errstr != NULL)
165 errx(1, "bad -l argument, %s: %s", errstr,
166 optarg);
167 break;
168 case 'p': /* pass unknown control sequences */
169 pass_unknown_seqs = 1;
170 break;
171 case 'x': /* do not compress spaces into tabs */
172 compress_spaces = 0;
173 break;
174 case '?':
175 default:
176 usage();
177 }
178
179 if (optind != argc)
180 usage();
181
182 adjust = cur_col = extra_lines = warned = 0;
183 cur_line = max_line = nflushd_lines = this_line = 0;
184 cur_set = last_set = CS_NORMAL;
185 lines = l = alloc_line();
186
187 while ((ch = getwchar()) != WEOF) {
188 if (!iswgraph(ch)) {
189 switch (ch) {
190 case BS: /* can't go back further */
191 if (cur_col == 0)
192 continue;
193 --cur_col;
194 continue;
195 case CR:
196 cur_col = 0;
197 continue;
198 case ESC: /* just ignore EOF */
199 switch(getwchar()) {
200 /*
201 * In the input stream, accept both the
202 * XPG5 sequences ESC-digit and the
203 * traditional BSD sequences ESC-ctrl.
204 */
205 case '\007':
206 /* FALLTHROUGH */
207 case RLF:
208 addto_lineno(&cur_line, -2);
209 break;
210 case '\010':
211 /* FALLTHROUGH */
212 case RHLF:
213 addto_lineno(&cur_line, -1);
214 break;
215 case '\011':
216 /* FALLTHROUGH */
217 case FHLF:
218 addto_lineno(&cur_line, 1);
219 if (cur_line > max_line)
220 max_line = cur_line;
221 }
222 continue;
223 case NL:
224 addto_lineno(&cur_line, 2);
225 if (cur_line > max_line)
226 max_line = cur_line;
227 cur_col = 0;
228 continue;
229 case SPACE:
230 ++cur_col;
231 continue;
232 case SI:
233 cur_set = CS_NORMAL;
234 continue;
235 case SO:
236 cur_set = CS_ALTERNATE;
237 continue;
238 case TAB: /* adjust column */
239 cur_col |= 7;
240 ++cur_col;
241 continue;
242 case VT:
243 addto_lineno(&cur_line, -2);
244 continue;
245 }
246 if (iswspace(ch)) {
247 if ((width = wcwidth(ch)) > 0)
248 cur_col += width;
249 continue;
250 }
251 if (!pass_unknown_seqs)
252 continue;
253 }
254
255 /* Must stuff ch in a line - are we at the right one? */
256 if (cur_line + adjust != this_line) {
257 LINE *lnew;
258
259 /* round up to next line */
260 adjust = !fine && (cur_line & 1);
261
262 if (cur_line + adjust < this_line) {
263 while (cur_line + adjust < this_line &&
264 l->l_prev != NULL) {
265 l = l->l_prev;
266 this_line--;
267 }
268 if (cur_line + adjust < this_line) {
269 if (nflushd_lines == 0) {
270 /*
271 * Allow backup past first
272 * line if nothing has been
273 * flushed yet.
274 */
275 while (cur_line + adjust
276 < this_line) {
277 lnew = alloc_line();
278 l->l_prev = lnew;
279 lnew->l_next = l;
280 l = lines = lnew;
281 extra_lines++;
282 this_line--;
283 }
284 } else {
285 if (!warned++)
286 dowarn(cur_line);
287 cur_line = this_line - adjust;
288 }
289 }
290 } else {
291 /* may need to allocate here */
292 while (cur_line + adjust > this_line) {
293 if (l->l_next == NULL) {
294 l->l_next = alloc_line();
295 l->l_next->l_prev = l;
296 }
297 l = l->l_next;
298 this_line++;
299 }
300 }
301 if (this_line > nflushd_lines &&
302 this_line - nflushd_lines >=
303 max_bufd_lines + BUFFER_MARGIN) {
304 if (extra_lines) {
305 flush_lines(extra_lines);
306 extra_lines = 0;
307 }
308 flush_lines(this_line - nflushd_lines -
309 max_bufd_lines);
310 nflushd_lines = this_line - max_bufd_lines;
311 }
312 }
313 /* grow line's buffer? */
314 if (l->l_line_len + 1 >= l->l_lsize) {
315 int need;
316
317 need = l->l_lsize ? l->l_lsize * 2 : 90;
318 if ((l->l_line = realloc(l->l_line,
319 (unsigned)need * sizeof(CHAR))) == NULL)
320 err(1, NULL);
321 l->l_lsize = need;
322 }
323 c = &l->l_line[l->l_line_len++];
324 c->c_char = ch;
325 c->c_set = cur_set;
326 c->c_column = cur_col;
327 c->c_width = wcwidth(ch);
328 /*
329 * If things are put in out of order, they will need sorting
330 * when it is flushed.
331 */
332 if (cur_col < l->l_max_col)
333 l->l_needs_sort = 1;
334 else
335 l->l_max_col = cur_col;
336 if (c->c_width > 0)
337 cur_col += c->c_width;
338 }
339 if (ferror(stdin))
340 err(1, NULL);
341 if (extra_lines) {
342 /*
343 * Extra lines only exist if no lines have been flushed
344 * yet. This means that 'lines' must point to line zero
345 * after we flush the extra lines.
346 */
347 flush_lines(extra_lines);
348 l = lines;
349 this_line = 0;
350 }
351
352 /* goto the last line that had a character on it */
353 for (; l->l_next; l = l->l_next)
354 this_line++;
355 flush_lines(this_line - nflushd_lines + 1);
356
357 /* make sure we leave things in a sane state */
358 if (last_set != CS_NORMAL)
359 PUTC(SI);
360
361 /* flush out the last few blank lines */
362 if (max_line >= this_line)
363 nblank_lines = max_line - this_line + (max_line & 1);
364 if (nblank_lines == 0)
365 /* end with a newline even if the source doesn't */
366 nblank_lines = 2;
367 flush_blanks();
368 exit(0);
369 }
370
371 /*
372 * Prints the first 'nflush' lines. Printed lines are freed.
373 * After this function returns, 'lines' points to the first
374 * of the remaining lines, and 'nblank_lines' will have the
375 * number of half line feeds between the final flushed line
376 * and the first remaining line.
377 */
378 static void
flush_lines(int nflush)379 flush_lines(int nflush)
380 {
381 LINE *l;
382
383 while (--nflush >= 0) {
384 l = lines;
385 lines = l->l_next;
386 if (l->l_line) {
387 flush_blanks();
388 flush_line(l);
389 free(l->l_line);
390 }
391 if (l->l_next)
392 nblank_lines++;
393 free_line(l);
394 }
395 if (lines)
396 lines->l_prev = NULL;
397 }
398
399 /*
400 * Print a number of newline/half newlines.
401 * nblank_lines is the number of half line feeds.
402 */
403 static void
flush_blanks(void)404 flush_blanks(void)
405 {
406 int half, i, nb;
407
408 half = 0;
409 nb = nblank_lines;
410 if (nb & 1) {
411 if (fine)
412 half = 1;
413 else
414 nb++;
415 }
416 nb /= 2;
417 for (i = nb; --i >= 0;)
418 PUTC('\n');
419 if (half) {
420 PUTC(ESC);
421 PUTC(FHLF);
422 if (!nb)
423 PUTC('\r');
424 }
425 nblank_lines = 0;
426 }
427
428 /*
429 * Write a line to stdout taking care of space to tab conversion (-h flag)
430 * and character set shifts.
431 */
432 static void
flush_line(LINE * l)433 flush_line(LINE *l)
434 {
435 CHAR *c, *endc;
436 int i, j, nchars, last_col, save, this_col, tot;
437
438 last_col = 0;
439 nchars = l->l_line_len;
440
441 if (l->l_needs_sort) {
442 static CHAR *sorted;
443 static int count_size, *count, sorted_size;
444
445 /*
446 * Do an O(n) sort on l->l_line by column being careful to
447 * preserve the order of characters in the same column.
448 */
449 if (l->l_lsize > sorted_size) {
450 sorted_size = l->l_lsize;
451 if ((sorted = realloc(sorted,
452 (unsigned)sizeof(CHAR) * sorted_size)) == NULL)
453 err(1, NULL);
454 }
455 if (l->l_max_col >= count_size) {
456 count_size = l->l_max_col + 1;
457 if ((count = realloc(count,
458 (unsigned)sizeof(int) * count_size)) == NULL)
459 err(1, NULL);
460 }
461 memset(count, 0, sizeof(int) * l->l_max_col + 1);
462 for (i = nchars, c = l->l_line; --i >= 0; c++)
463 count[c->c_column]++;
464
465 /*
466 * calculate running total (shifted down by 1) to use as
467 * indices into new line.
468 */
469 for (tot = 0, i = 0; i <= l->l_max_col; i++) {
470 save = count[i];
471 count[i] = tot;
472 tot += save;
473 }
474
475 for (i = nchars, c = l->l_line; --i >= 0; c++)
476 sorted[count[c->c_column]++] = *c;
477 c = sorted;
478 } else
479 c = l->l_line;
480 while (nchars > 0) {
481 this_col = c->c_column;
482 endc = c;
483 do {
484 ++endc;
485 } while (--nchars > 0 && this_col == endc->c_column);
486
487 /* if -b only print last character */
488 if (no_backspaces) {
489 c = endc - 1;
490 if (nchars > 0 &&
491 this_col + c->c_width > endc->c_column)
492 continue;
493 }
494
495 if (this_col > last_col) {
496 int nspace = this_col - last_col;
497
498 if (compress_spaces && nspace > 1) {
499 while (1) {
500 int tab_col, tab_size;
501
502 tab_col = (last_col + 8) & ~7;
503 if (tab_col > this_col)
504 break;
505 tab_size = tab_col - last_col;
506 if (tab_size == 1)
507 PUTC(' ');
508 else
509 PUTC('\t');
510 nspace -= tab_size;
511 last_col = tab_col;
512 }
513 }
514 while (--nspace >= 0)
515 PUTC(' ');
516 last_col = this_col;
517 }
518
519 for (;;) {
520 if (c->c_set != last_set) {
521 switch (c->c_set) {
522 case CS_NORMAL:
523 PUTC(SI);
524 break;
525 case CS_ALTERNATE:
526 PUTC(SO);
527 }
528 last_set = c->c_set;
529 }
530 PUTC(c->c_char);
531 if ((c + 1) < endc)
532 for (j = 0; j < c->c_width; j++)
533 PUTC('\b');
534 if (++c >= endc)
535 break;
536 }
537 last_col += (c - 1)->c_width;
538 }
539 }
540
541 /*
542 * Increment or decrement a line number, checking for overflow.
543 * Stop one below INT_MAX such that the adjust variable is safe.
544 */
545 void
addto_lineno(int * lno,int offset)546 addto_lineno(int *lno, int offset)
547 {
548 if (offset > 0) {
549 if (*lno >= INT_MAX - offset)
550 errx(1, "too many lines");
551 } else {
552 if (*lno < INT_MIN - offset)
553 errx(1, "too many reverse line feeds");
554 }
555 *lno += offset;
556 }
557
558 #define NALLOC 64
559
560 static LINE *line_freelist;
561
562 static LINE *
alloc_line(void)563 alloc_line(void)
564 {
565 LINE *l;
566 int i;
567
568 if (!line_freelist) {
569 if ((l = realloc(NULL, sizeof(LINE) * NALLOC)) == NULL)
570 err(1, NULL);
571 line_freelist = l;
572 for (i = 1; i < NALLOC; i++, l++)
573 l->l_next = l + 1;
574 l->l_next = NULL;
575 }
576 l = line_freelist;
577 line_freelist = l->l_next;
578
579 memset(l, 0, sizeof(LINE));
580 return (l);
581 }
582
583 static void
free_line(LINE * l)584 free_line(LINE *l)
585 {
586
587 l->l_next = line_freelist;
588 line_freelist = l;
589 }
590
591 static void
usage(void)592 usage(void)
593 {
594
595 (void)fprintf(stderr, "usage: col [-bfhpx] [-l nline]\n");
596 exit(1);
597 }
598
599 static void
dowarn(int line)600 dowarn(int line)
601 {
602
603 warnx("warning: can't back up %s",
604 line < 0 ? "past first line" : "-- line already flushed");
605 }
606