usr.bin/col/col.c

   1 /*      $NetBSD: col.c,v 1.14 2005/02/17 17:12:42 xtraeme Exp $ */
   2
   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 #include <sys/cdefs.h>
  36 #ifndef lint
  37 __COPYRIGHT("@(#) Copyright (c) 1990, 1993, 1994\
  38  The Regents of the University of California.  All rights reserved.");
  39 #endif /* not lint */
  40
  41 #ifndef lint
  42 #if 0
  43 static char sccsid[] = "@(#)col.c       8.5 (Berkeley) 5/4/95";
  44 #endif
  45 __RCSID("$NetBSD: col.c,v 1.14 2005/02/17 17:12:42 xtraeme Exp $");
  46 #endif /* not lint */
  47
  48 #include <ctype.h>
  49 #include <err.h>
  50 #include <string.h>
  51 #include <stdio.h>
  52 #include <stdlib.h>
  53 #include <unistd.h>
  54
  55 #define BS      '\b'            /* backspace */
  56 #define TAB     '\t'            /* tab */
  57 #define SPACE   ' '             /* space */
  58 #define NL      '\n'            /* newline */
  59 #define CR      '\r'            /* carriage return */
  60 #define ESC     '\033'          /* escape */
  61 #define SI      '\017'          /* shift in to normal character set */
  62 #define SO      '\016'          /* shift out to alternate character set */
  63 #define VT      '\013'          /* vertical tab (aka reverse line feed) */
  64 #define RLF     '\007'          /* ESC-07 reverse line feed */
  65 #define RHLF    '\010'          /* ESC-010 reverse half-line feed */
  66 #define FHLF    '\011'          /* ESC-011 forward half-line feed */
  67
  68 /* build up at least this many lines before flushing them out */
  69 #define BUFFER_MARGIN           32
  70
  71 typedef char CSET;
  72
  73 typedef struct char_str {
  74 #define CS_NORMAL       1
  75 #define CS_ALTERNATE    2
  76         short           c_column;       /* column character is in */
  77         CSET            c_set;          /* character set (currently only 2) */
  78         char            c_char;         /* character in question */
  79 } CHAR;
  80
  81 typedef struct line_str LINE;
  82 struct line_str {
  83         CHAR    *l_line;                /* characters on the line */
  84         LINE    *l_prev;                /* previous line */
  85         LINE    *l_next;                /* next line */
  86         int     l_lsize;                /* allocated sizeof l_line */
  87         int     l_line_len;             /* strlen(l_line) */
  88         int     l_needs_sort;           /* set if chars went in out of order */
  89         int     l_max_col;              /* max column in the line */
  90 };
  91
  92 LINE   *alloc_line(void);
  93 void    dowarn(int);
  94 void    flush_line(LINE *);
  95 void    flush_lines(int);
  96 void    flush_blanks(void);
  97 void    free_line(LINE *);
  98 void    usage(void);
  99 void    wrerr(void);
 100 void   *xmalloc(void *, size_t);
 101
 102 CSET    last_set;               /* char_set of last char printed */
 103 LINE   *lines;
 104 int     compress_spaces;        /* if doing space -> tab conversion */
 105 int     fine;                   /* if `fine' resolution (half lines) */
 106 int     max_bufd_lines;         /* max # lines to keep in memory */
 107 int     nblank_lines;           /* # blanks after last flushed line */
 108 int     no_backspaces;          /* if not to output any backspaces */
 109 int     pass_unknown_seqs;      /* whether to pass unknown control sequences */
 110
 111 #define PUTC(ch) \
 112         if (putchar(ch) == EOF) \
 113                 wrerr();
 114
 115 int
 116 main(int argc, char **argv)
 117 {
 118         int ch;
 119         CHAR *c;
 120         CSET cur_set;                   /* current character set */
 121         LINE *l;                        /* current line */
 122         int extra_lines;                /* # of lines above first line */
 123         int cur_col;                    /* current column */
 124         int cur_line;                   /* line number of current position */
 125         int max_line;                   /* max value of cur_line */
 126         int this_line;                  /* line l points to */
 127         int nflushd_lines;              /* number of lines that were flushed */
 128         int adjust, opt, warned;
 129
 130         max_bufd_lines = 128;
 131         compress_spaces = 1;            /* compress spaces into tabs */
 132         pass_unknown_seqs = 0;          /* remove unknown escape sequences */
 133         while ((opt = getopt(argc, argv, "bfhl:px")) != -1)
 134                 switch (opt) {
 135                 case 'b':               /* do not output backspaces */
 136                         no_backspaces = 1;
 137                         break;
 138                 case 'f':               /* allow half forward line feeds */
 139                         fine = 1;
 140                         break;
 141                 case 'h':               /* compress spaces into tabs */
 142                         compress_spaces = 1;
 143                         break;
 144                 case 'l':               /* buffered line count */
 145                         if ((max_bufd_lines = atoi(optarg)) <= 0) {
 146                                 (void)fprintf(stderr,
 147                                     "col: bad -l argument %s.\n", optarg);
 148                                 exit(EXIT_FAILURE);
 149                         }
 150                         break;
 151                 case 'p':               /* pass unknown control sequences */
 152                         pass_unknown_seqs = 1;
 153                         break;
 154                 case 'x':               /* do not compress spaces into tabs */
 155                         compress_spaces = 0;
 156                         break;
 157                 case '?':
 158                 default:
 159                         usage();
 160                 }
 161
 162         if (optind != argc)
 163                 usage();
 164
 165         /* this value is in half lines */
 166         max_bufd_lines *= 2;
 167
 168         adjust = cur_col = extra_lines = warned = 0;
 169         cur_line = max_line = nflushd_lines = this_line = 0;
 170         cur_set = last_set = CS_NORMAL;
 171         lines = l = alloc_line();
 172
 173         while ((ch = getchar()) != EOF) {
 174                 if (!isgraph(ch)) {
 175                         switch (ch) {
 176                         case BS:                /* can't go back further */
 177                                 if (cur_col == 0)
 178                                         continue;
 179                                 --cur_col;
 180                                 continue;
 181                         case CR:
 182                                 cur_col = 0;
 183                                 continue;
 184                         case ESC:               /* just ignore EOF */
 185                                 switch(getchar()) {
 186                                 case RLF:
 187                                         cur_line -= 2;
 188                                         break;
 189                                 case RHLF:
 190                                         cur_line--;
 191                                         break;
 192                                 case FHLF:
 193                                         cur_line++;
 194                                         if (cur_line > max_line)
 195                                                 max_line = cur_line;
 196                                 }
 197                                 continue;
 198                         case NL:
 199                                 cur_line += 2;
 200                                 if (cur_line > max_line)
 201                                         max_line = cur_line;
 202                                 cur_col = 0;
 203                                 continue;
 204                         case SPACE:
 205                                 ++cur_col;
 206                                 continue;
 207                         case SI:
 208                                 cur_set = CS_NORMAL;
 209                                 continue;
 210                         case SO:
 211                                 cur_set = CS_ALTERNATE;
 212                                 continue;
 213                         case TAB:               /* adjust column */
 214                                 cur_col |= 7;
 215                                 ++cur_col;
 216                                 continue;
 217                         case VT:
 218                                 cur_line -= 2;
 219                                 continue;
 220                         }
 221                         if (!pass_unknown_seqs)
 222                                 continue;
 223                 }
 224
 225                 /* Must stuff ch in a line - are we at the right one? */
 226                 if (cur_line != this_line - adjust) {
 227                         LINE *lnew;
 228                         int nmove;
 229
 230                         adjust = 0;
 231                         nmove = cur_line - this_line;
 232                         if (!fine) {
 233                                 /* round up to next line */
 234                                 if (cur_line & 1) {
 235                                         adjust = 1;
 236                                         nmove++;
 237                                 }
 238                         }
 239                         if (nmove < 0) {
 240                                 for (; nmove < 0 && l->l_prev; nmove++)
 241                                         l = l->l_prev;
 242                                 if (nmove) {
 243                                         if (nflushd_lines == 0) {
 244                                                 /*
 245                                                  * Allow backup past first
 246                                                  * line if nothing has been
 247                                                  * flushed yet.
 248                                                  */
 249                                                 for (; nmove < 0; nmove++) {
 250                                                         lnew = alloc_line();
 251                                                         l->l_prev = lnew;
 252                                                         lnew->l_next = l;
 253                                                         l = lines = lnew;
 254                                                         extra_lines++;
 255                                                 }
 256                                         } else {
 257                                                 if (!warned++)
 258                                                         dowarn(cur_line);
 259                                                 cur_line -= nmove;
 260                                         }
 261                                 }
 262                         } else {
 263                                 /* may need to allocate here */
 264                                 for (; nmove > 0 && l->l_next; nmove--)
 265                                         l = l->l_next;
 266                                 for (; nmove > 0; nmove--) {
 267                                         lnew = alloc_line();
 268                                         lnew->l_prev = l;
 269                                         l->l_next = lnew;
 270                                         l = lnew;
 271                                 }
 272                         }
 273                         this_line = cur_line + adjust;
 274                         nmove = this_line - nflushd_lines;
 275                         if (nmove >= max_bufd_lines + BUFFER_MARGIN) {
 276                                 nflushd_lines += nmove - max_bufd_lines;
 277                                 flush_lines(nmove - max_bufd_lines);
 278                         }
 279                 }
 280                 /* grow line's buffer? */
 281                 if (l->l_line_len + 1 >= l->l_lsize) {
 282                         int need;
 283
 284                         need = l->l_lsize ? l->l_lsize * 2 : 90;
 285                         l->l_line = (CHAR *)xmalloc((void *) l->l_line,
 286                             (unsigned) need * sizeof(CHAR));
 287                         l->l_lsize = need;
 288                 }
 289                 c = &l->l_line[l->l_line_len++];
 290                 c->c_char = ch;
 291                 c->c_set = cur_set;
 292                 c->c_column = cur_col;
 293                 /*
 294                  * If things are put in out of order, they will need sorting
 295                  * when it is flushed.
 296                  */
 297                 if (cur_col < l->l_max_col)
 298                         l->l_needs_sort = 1;
 299                 else
 300                         l->l_max_col = cur_col;
 301                 cur_col++;
 302         }
 303         if (max_line == 0)
 304                 exit(EXIT_SUCCESS);     /* no lines, so just exit */
 305
 306         /* goto the last line that had a character on it */
 307         for (; l->l_next; l = l->l_next)
 308                 this_line++;
 309         flush_lines(this_line - nflushd_lines + extra_lines + 1);
 310
 311         /* make sure we leave things in a sane state */
 312         if (last_set != CS_NORMAL)
 313                 PUTC('\017');
 314
 315         /* flush out the last few blank lines */
 316         nblank_lines = max_line - this_line;
 317         if (max_line & 1)
 318                 nblank_lines++;
 319         else if (!nblank_lines)
 320                 /* missing a \n on the last line? */
 321                 nblank_lines = 2;
 322         flush_blanks();
 323         exit(EXIT_SUCCESS);
 324         /* NOTREACHED */
 325 }
 326
 327 void
 328 flush_lines(int nflush)
 329 {
 330         LINE *l;
 331
 332         while (--nflush >= 0) {
 333                 l = lines;
 334                 lines = l->l_next;
 335                 if (l->l_line) {
 336                         flush_blanks();
 337                         flush_line(l);
 338                 }
 339                 nblank_lines++;
 340                 if (l->l_line)
 341                         (void)free((void *)l->l_line);
 342                 free_line(l);
 343         }
 344         if (lines)
 345                 lines->l_prev = NULL;
 346 }
 347
 348 /*
 349  * Print a number of newline/half newlines.  If fine flag is set, nblank_lines
 350  * is the number of half line feeds, otherwise it is the number of whole line
 351  * feeds.
 352  */
 353 void
 354 flush_blanks(void)
 355 {
 356         int half, i, nb;
 357
 358         half = 0;
 359         nb = nblank_lines;
 360         if (nb & 1) {
 361                 if (fine)
 362                         half = 1;
 363                 else
 364                         nb++;
 365         }
 366         nb /= 2;
 367         for (i = nb; --i >= 0;)
 368                 PUTC('\n');
 369         if (half) {
 370                 PUTC('\033');
 371                 PUTC('9');
 372                 if (!nb)
 373                         PUTC('\r');
 374         }
 375         nblank_lines = 0;
 376 }
 377
 378 /*
 379  * Write a line to stdout taking care of space to tab conversion (-h flag)
 380  * and character set shifts.
 381  */
 382 void
 383 flush_line(LINE *l)
 384 {
 385         CHAR *c, *endc;
 386         int nchars, last_col, this_col;
 387
 388         last_col = 0;
 389         nchars = l->l_line_len;
 390
 391         if (l->l_needs_sort) {
 392                 static CHAR *sorted;
 393                 static int count_size, *count, i, save, sorted_size, tot;
 394
 395                 /*
 396                  * Do an O(n) sort on l->l_line by column being careful to
 397                  * preserve the order of characters in the same column.
 398                  */
 399                 if (l->l_lsize > sorted_size) {
 400                         sorted_size = l->l_lsize;
 401                         sorted = (CHAR *)xmalloc((void *)sorted,
 402                             (unsigned)sizeof(CHAR) * sorted_size);
 403                 }
 404                 if (l->l_max_col >= count_size) {
 405                         count_size = l->l_max_col + 1;
 406                         count = (int *)xmalloc((void *)count,
 407                             (unsigned)sizeof(int) * count_size);
 408                 }
 409                 (void)memset(count, 0, sizeof(int) * l->l_max_col + 1);
 410                 for (i = nchars, c = l->l_line; --i >= 0; c++)
 411                         count[c->c_column]++;
 412
 413                 /*
 414                  * calculate running total (shifted down by 1) to use as
 415                  * indices into new line.
 416                  */
 417                 for (tot = 0, i = 0; i <= l->l_max_col; i++) {
 418                         save = count[i];
 419                         count[i] = tot;
 420                         tot += save;
 421                 }
 422
 423                 for (i = nchars, c = l->l_line; --i >= 0; c++)
 424                         sorted[count[c->c_column]++] = *c;
 425                 c = sorted;
 426         } else
 427                 c = l->l_line;
 428         while (nchars > 0) {
 429                 this_col = c->c_column;
 430                 endc = c;
 431                 do {
 432                         ++endc;
 433                 } while (--nchars > 0 && this_col == endc->c_column);
 434
 435                 /* if -b only print last character */
 436                 if (no_backspaces)
 437                         c = endc - 1;
 438
 439                 if (this_col > last_col) {
 440                         int nspace = this_col - last_col;
 441
 442                         if (compress_spaces && nspace > 1) {
 443                                 int ntabs;
 444
 445                                 ntabs = ((last_col % 8) + nspace) / 8;
 446                                 if (ntabs) {
 447                                         nspace -= (ntabs * 8) - (last_col % 8);
 448                                         while (--ntabs >= 0)
 449                                                 PUTC('\t');
 450                                 }
 451                         }
 452                         while (--nspace >= 0)
 453                                 PUTC(' ');
 454                         last_col = this_col;
 455                 }
 456                 last_col++;
 457
 458                 for (;;) {
 459                         if (c->c_set != last_set) {
 460                                 switch (c->c_set) {
 461                                 case CS_NORMAL:
 462                                         PUTC('\017');
 463                                         break;
 464                                 case CS_ALTERNATE:
 465                                         PUTC('\016');
 466                                 }
 467                                 last_set = c->c_set;
 468                         }
 469                         PUTC(c->c_char);
 470                         if (++c >= endc)
 471                                 break;
 472                         PUTC('\b');
 473                 }
 474         }
 475 }
 476
 477 #define NALLOC 64
 478
 479 static LINE *line_freelist;
 480
 481 LINE *
 482 alloc_line(void)
 483 {
 484         LINE *l;
 485         int i;
 486
 487         if (!line_freelist) {
 488                 l = (LINE *)xmalloc((void *)NULL, sizeof(LINE) * NALLOC);
 489                 line_freelist = l;
 490                 for (i = 1; i < NALLOC; i++, l++)
 491                         l->l_next = l + 1;
 492                 l->l_next = NULL;
 493         }
 494         l = line_freelist;
 495         line_freelist = l->l_next;
 496
 497         (void)memset(l, 0, sizeof(LINE));
 498         return (l);
 499 }
 500
 501 void
 502 free_line(LINE *l)
 503 {
 504
 505         l->l_next = line_freelist;
 506         line_freelist = l;
 507 }
 508
 509 void *
 510 xmalloc(void *p, size_t size)
 511 {
 512         void *q;
 513
 514         if (!(q = (void *)realloc(p, size)))
 515                 err(EXIT_FAILURE, "realloc");
 516         p = q;
 517         return (p);
 518 }
 519
 520 void
 521 usage(void)
 522 {
 523
 524         (void)fprintf(stderr, "usage: col [-bfpx] [-l nline]\n");
 525         exit(EXIT_FAILURE);
 526 }
 527
 528 void
 529 wrerr(void)
 530 {
 531
 532         (void)fprintf(stderr, "col: write error.\n");
 533         exit(EXIT_FAILURE);
 534 }
 535
 536 void
 537 dowarn(int line)
 538 {
 539
 540         warnx("warning: can't back up %s",
 541                 line < 0 ? "past first line" : "-- line already flushed");
 542 }