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