Replace all casts of NULL to something with NULL.
[dragonfly.git] / usr.bin / col / col.c
1 /*-
2  * Copyright (c) 1990, 1993, 1994
3  *      The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Michael Rendell of the Memorial University of Newfoundland.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *      This product includes software developed by the University of
19  *      California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  * @(#) Copyright (c) 1990, 1993, 1994 The Regents of the University of California.  All rights reserved.
37  * @(#)col.c    8.5 (Berkeley) 5/4/95
38  * $FreeBSD: src/usr.bin/col/col.c,v 1.6.6.4 2001/08/02 01:27:12 obrien Exp $
39  * $DragonFly: src/usr.bin/col/col.c,v 1.5 2006/08/03 16:40:48 swildner Exp $
40  */
41
42 #include <ctype.h>
43 #include <err.h>
44 #include <string.h>
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <unistd.h>
48 #include <locale.h>
49
50 #define BS      '\b'            /* backspace */
51 #define TAB     '\t'            /* tab */
52 #define SPACE   ' '             /* space */
53 #define NL      '\n'            /* newline */
54 #define CR      '\r'            /* carriage return */
55 #define ESC     '\033'          /* escape */
56 #define SI      '\017'          /* shift in to normal character set */
57 #define SO      '\016'          /* shift out to alternate character set */
58 #define VT      '\013'          /* vertical tab (aka reverse line feed) */
59 #define RLF     '\007'          /* ESC-07 reverse line feed */
60 #define RHLF    '\010'          /* ESC-010 reverse half-line feed */
61 #define FHLF    '\011'          /* ESC-011 forward half-line feed */
62
63 /* build up at least this many lines before flushing them out */
64 #define BUFFER_MARGIN           32
65
66 typedef char CSET;
67
68 typedef struct char_str {
69 #define CS_NORMAL       1
70 #define CS_ALTERNATE    2
71         short           c_column;       /* column character is in */
72         CSET            c_set;          /* character set (currently only 2) */
73         char            c_char;         /* character in question */
74 } CHAR;
75
76 typedef struct line_str LINE;
77 struct line_str {
78         CHAR    *l_line;                /* characters on the line */
79         LINE    *l_prev;                /* previous line */
80         LINE    *l_next;                /* next line */
81         int     l_lsize;                /* allocated sizeof l_line */
82         int     l_line_len;             /* strlen(l_line) */
83         int     l_needs_sort;           /* set if chars went in out of order */
84         int     l_max_col;              /* max column in the line */
85 };
86
87 LINE   *alloc_line(void);
88 void    dowarn(int);
89 void    flush_line(LINE *);
90 void    flush_lines(int);
91 void    flush_blanks(void);
92 void    free_line(LINE *);
93 int     main(int, char **);
94 void    usage(void);
95
96 CSET    last_set;               /* char_set of last char printed */
97 LINE   *lines;
98 int     compress_spaces;        /* if doing space -> tab conversion */
99 int     fine;                   /* if `fine' resolution (half lines) */
100 int     max_bufd_lines;         /* max # lines to keep in memory */
101 int     nblank_lines;           /* # blanks after last flushed line */
102 int     no_backspaces;          /* if not to output any backspaces */
103 int     pass_unknown_seqs;      /* pass unknown control sequences */
104
105 #define PUTC(ch) \
106         do {                                    \
107                 if (putchar(ch) == EOF)         \
108                         errx(1, "write error"); \
109         } while (0)
110
111 int
112 main(int argc, char **argv)
113 {
114         int ch;
115         CHAR *c;
116         CSET cur_set;                   /* current character set */
117         LINE *l;                        /* current line */
118         int extra_lines;                /* # of lines above first line */
119         int cur_col;                    /* current column */
120         int cur_line;                   /* line number of current position */
121         int max_line;                   /* max value of cur_line */
122         int this_line;                  /* line l points to */
123         int nflushd_lines;              /* number of lines that were flushed */
124         int adjust, opt, warned;
125
126         (void)setlocale(LC_CTYPE, "");
127
128         max_bufd_lines = 128;
129         compress_spaces = 1;            /* compress spaces into tabs */
130         while ((opt = getopt(argc, argv, "bfhl:px")) != -1)
131                 switch (opt) {
132                 case 'b':               /* do not output backspaces */
133                         no_backspaces = 1;
134                         break;
135                 case 'f':               /* allow half forward line feeds */
136                         fine = 1;
137                         break;
138                 case 'h':               /* compress spaces into tabs */
139                         compress_spaces = 1;
140                         break;
141                 case 'l':               /* buffered line count */
142                         if ((max_bufd_lines = atoi(optarg)) <= 0)
143                                 errx(1, "bad -l argument %s", optarg);
144                         break;
145                 case 'p':               /* pass unknown control sequences */
146                         pass_unknown_seqs = 1;
147                         break;
148                 case 'x':               /* do not compress spaces into tabs */
149                         compress_spaces = 0;
150                         break;
151                 case '?':
152                 default:
153                         usage();
154                 }
155
156         if (optind != argc)
157                 usage();
158
159         /* this value is in half lines */
160         max_bufd_lines *= 2;
161
162         adjust = cur_col = extra_lines = warned = 0;
163         cur_line = max_line = nflushd_lines = this_line = 0;
164         cur_set = last_set = CS_NORMAL;
165         lines = l = alloc_line();
166
167         while ((ch = getchar()) != EOF) {
168                 if (!isgraph(ch)) {
169                         switch (ch) {
170                         case BS:                /* can't go back further */
171                                 if (cur_col == 0)
172                                         continue;
173                                 --cur_col;
174                                 continue;
175                         case CR:
176                                 cur_col = 0;
177                                 continue;
178                         case ESC:               /* just ignore EOF */
179                                 switch(getchar()) {
180                                 case RLF:
181                                         cur_line -= 2;
182                                         break;
183                                 case RHLF:
184                                         cur_line--;
185                                         break;
186                                 case FHLF:
187                                         cur_line++;
188                                         if (cur_line > max_line)
189                                                 max_line = cur_line;
190                                 }
191                                 continue;
192                         case NL:
193                                 cur_line += 2;
194                                 if (cur_line > max_line)
195                                         max_line = cur_line;
196                                 cur_col = 0;
197                                 continue;
198                         case SPACE:
199                                 ++cur_col;
200                                 continue;
201                         case SI:
202                                 cur_set = CS_NORMAL;
203                                 continue;
204                         case SO:
205                                 cur_set = CS_ALTERNATE;
206                                 continue;
207                         case TAB:               /* adjust column */
208                                 cur_col |= 7;
209                                 ++cur_col;
210                                 continue;
211                         case VT:
212                                 cur_line -= 2;
213                                 continue;
214                         }
215                         if (!pass_unknown_seqs)
216                                 continue;
217                 }
218
219                 /* Must stuff ch in a line - are we at the right one? */
220                 if (cur_line != this_line - adjust) {
221                         LINE *lnew;
222                         int nmove;
223
224                         adjust = 0;
225                         nmove = cur_line - this_line;
226                         if (!fine) {
227                                 /* round up to next line */
228                                 if (cur_line & 1) {
229                                         adjust = 1;
230                                         nmove++;
231                                 }
232                         }
233                         if (nmove < 0) {
234                                 for (; nmove < 0 && l->l_prev; nmove++)
235                                         l = l->l_prev;
236                                 if (nmove) {
237                                         if (nflushd_lines == 0) {
238                                                 /*
239                                                  * Allow backup past first
240                                                  * line if nothing has been
241                                                  * flushed yet.
242                                                  */
243                                                 for (; nmove < 0; nmove++) {
244                                                         lnew = alloc_line();
245                                                         l->l_prev = lnew;
246                                                         lnew->l_next = l;
247                                                         l = lines = lnew;
248                                                         extra_lines++;
249                                                 }
250                                         } else {
251                                                 if (!warned++)
252                                                         dowarn(cur_line);
253                                                 cur_line -= nmove;
254                                         }
255                                 }
256                         } else {
257                                 /* may need to allocate here */
258                                 for (; nmove > 0 && l->l_next; nmove--)
259                                         l = l->l_next;
260                                 for (; nmove > 0; nmove--) {
261                                         lnew = alloc_line();
262                                         lnew->l_prev = l;
263                                         l->l_next = lnew;
264                                         l = lnew;
265                                 }
266                         }
267                         this_line = cur_line + adjust;
268                         nmove = this_line - nflushd_lines;
269                         if (nmove >= max_bufd_lines + BUFFER_MARGIN) {
270                                 nflushd_lines += nmove - max_bufd_lines;
271                                 flush_lines(nmove - max_bufd_lines);
272                         }
273                 }
274                 /* grow line's buffer? */
275                 if (l->l_line_len + 1 >= l->l_lsize) {
276                         int need;
277
278                         need = l->l_lsize ? l->l_lsize * 2 : 90;
279                         if ((l->l_line = realloc(l->l_line,
280                             (unsigned)need * sizeof(CHAR))) == NULL)
281                                 err(1, NULL);
282                         l->l_lsize = need;
283                 }
284                 c = &l->l_line[l->l_line_len++];
285                 c->c_char = ch;
286                 c->c_set = cur_set;
287                 c->c_column = cur_col;
288                 /*
289                  * If things are put in out of order, they will need sorting
290                  * when it is flushed.
291                  */
292                 if (cur_col < l->l_max_col)
293                         l->l_needs_sort = 1;
294                 else
295                         l->l_max_col = cur_col;
296                 cur_col++;
297         }
298         if (max_line == 0)
299                 exit(0);        /* no lines, so just exit */
300
301         /* goto the last line that had a character on it */
302         for (; l->l_next; l = l->l_next)
303                 this_line++;
304         flush_lines(this_line - nflushd_lines + extra_lines + 1);
305
306         /* make sure we leave things in a sane state */
307         if (last_set != CS_NORMAL)
308                 PUTC('\017');
309
310         /* flush out the last few blank lines */
311         nblank_lines = max_line - this_line;
312         if (max_line & 1)
313                 nblank_lines++;
314         else if (!nblank_lines)
315                 /* missing a \n on the last line? */
316                 nblank_lines = 2;
317         flush_blanks();
318         exit(0);
319 }
320
321 void
322 flush_lines(int nflush)
323 {
324         LINE *l;
325
326         while (--nflush >= 0) {
327                 l = lines;
328                 lines = l->l_next;
329                 if (l->l_line) {
330                         flush_blanks();
331                         flush_line(l);
332                 }
333                 nblank_lines++;
334                 if (l->l_line)
335                         (void)free(l->l_line);
336                 free_line(l);
337         }
338         if (lines)
339                 lines->l_prev = NULL;
340 }
341
342 /*
343  * Print a number of newline/half newlines.  If fine flag is set, nblank_lines
344  * is the number of half line feeds, otherwise it is the number of whole line
345  * feeds.
346  */
347 void
348 flush_blanks(void)
349 {
350         int half, i, nb;
351
352         half = 0;
353         nb = nblank_lines;
354         if (nb & 1) {
355                 if (fine)
356                         half = 1;
357                 else
358                         nb++;
359         }
360         nb /= 2;
361         for (i = nb; --i >= 0;)
362                 PUTC('\n');
363         if (half) {
364                 PUTC('\033');
365                 PUTC('9');
366                 if (!nb)
367                         PUTC('\r');
368         }
369         nblank_lines = 0;
370 }
371
372 /*
373  * Write a line to stdout taking care of space to tab conversion (-h flag)
374  * and character set shifts.
375  */
376 void
377 flush_line(LINE *l)
378 {
379         CHAR *c, *endc;
380         int nchars, last_col, this_col;
381
382         last_col = 0;
383         nchars = l->l_line_len;
384
385         if (l->l_needs_sort) {
386                 static CHAR *sorted;
387                 static int count_size, *count, i, save, sorted_size, tot;
388
389                 /*
390                  * Do an O(n) sort on l->l_line by column being careful to
391                  * preserve the order of characters in the same column.
392                  */
393                 if (l->l_lsize > sorted_size) {
394                         sorted_size = l->l_lsize;
395                         if ((sorted = realloc(sorted,
396                             (unsigned)sizeof(CHAR) * sorted_size)) == NULL)
397                                 err(1, NULL);
398                 }
399                 if (l->l_max_col >= count_size) {
400                         count_size = l->l_max_col + 1;
401                         if ((count = realloc(count,
402                             (unsigned)sizeof(int) * count_size)) == NULL)
403                                 err(1, NULL);
404                 }
405                 memset(count, 0, sizeof(int) * l->l_max_col + 1);
406                 for (i = nchars, c = l->l_line; --i >= 0; c++)
407                         count[c->c_column]++;
408
409                 /*
410                  * calculate running total (shifted down by 1) to use as
411                  * indices into new line.
412                  */
413                 for (tot = 0, i = 0; i <= l->l_max_col; i++) {
414                         save = count[i];
415                         count[i] = tot;
416                         tot += save;
417                 }
418
419                 for (i = nchars, c = l->l_line; --i >= 0; c++)
420                         sorted[count[c->c_column]++] = *c;
421                 c = sorted;
422         } else
423                 c = l->l_line;
424         while (nchars > 0) {
425                 this_col = c->c_column;
426                 endc = c;
427                 do {
428                         ++endc;
429                 } while (--nchars > 0 && this_col == endc->c_column);
430
431                 /* if -b only print last character */
432                 if (no_backspaces)
433                         c = endc - 1;
434
435                 if (this_col > last_col) {
436                         int nspace = this_col - last_col;
437
438                         if (compress_spaces && nspace > 1) {
439                                 while (1) {
440                                         int tab_col, tab_size;
441
442                                         tab_col = (last_col + 8) & ~7;
443                                         if (tab_col > this_col)
444                                                 break;
445                                         tab_size = tab_col - last_col;
446                                         if (tab_size == 1)
447                                                 PUTC(' ');
448                                         else
449                                                 PUTC('\t');
450                                         nspace -= tab_size;
451                                         last_col = tab_col;
452                                 }
453                         }
454                         while (--nspace >= 0)
455                                 PUTC(' ');
456                         last_col = this_col;
457                 }
458                 last_col++;
459
460                 for (;;) {
461                         if (c->c_set != last_set) {
462                                 switch (c->c_set) {
463                                 case CS_NORMAL:
464                                         PUTC('\017');
465                                         break;
466                                 case CS_ALTERNATE:
467                                         PUTC('\016');
468                                 }
469                                 last_set = c->c_set;
470                         }
471                         PUTC(c->c_char);
472                         if (++c >= endc)
473                                 break;
474                         PUTC('\b');
475                 }
476         }
477 }
478
479 #define NALLOC 64
480
481 static LINE *line_freelist;
482
483 LINE *
484 alloc_line(void)
485 {
486         LINE *l;
487         int i;
488
489         if (!line_freelist) {
490                 if ((l = realloc(NULL, sizeof(LINE) * NALLOC)) == NULL)
491                         err(1, NULL);
492                 line_freelist = l;
493                 for (i = 1; i < NALLOC; i++, l++)
494                         l->l_next = l + 1;
495                 l->l_next = NULL;
496         }
497         l = line_freelist;
498         line_freelist = l->l_next;
499
500         memset(l, 0, sizeof(LINE));
501         return (l);
502 }
503
504 void
505 free_line(LINE *l)
506 {
507
508         l->l_next = line_freelist;
509         line_freelist = l;
510 }
511
512 void
513 usage(void)
514 {
515
516         (void)fprintf(stderr, "usage: col [-bfhpx] [-l nline]\n");
517         exit(1);
518 }
519
520 void
521 dowarn(int line)
522 {
523
524         warnx("warning: can't back up %s",
525                 line < 0 ? "past first line" : "-- line already flushed");
526 }