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
  33 #ifndef lint
  34 static const char copyright[] =
  35 "@(#) Copyright (c) 1990, 1993, 1994\n\
  36         The Regents of the University of California.  All rights reserved.\n";
  37 #endif
  38
  39 #if 0
  40 #ifndef lint
  41 static char sccsid[] = "@(#)col.c       8.5 (Berkeley) 5/4/95";
  42 #endif
  43 #endif
  44
  45 #include <sys/cdefs.h>
  46 __FBSDID("$FreeBSD$");
  47
  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
 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 (cap_enter() < 0 && errno != ENOSYS)
 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                 flush_lines(extra_lines);
 343
 344         /* goto the last line that had a character on it */
 345         for (; l->l_next; l = l->l_next)
 346                 this_line++;
 347         flush_lines(this_line - nflushd_lines + 1);
 348
 349         /* make sure we leave things in a sane state */
 350         if (last_set != CS_NORMAL)
 351                 PUTC(SI);
 352
 353         /* flush out the last few blank lines */
 354         if (max_line > this_line)
 355                 nblank_lines = max_line - this_line;
 356         if (max_line & 1)
 357                 nblank_lines++;
 358         flush_blanks();
 359         exit(0);
 360 }
 361
 362 static void
 363 flush_lines(int nflush)
 364 {
 365         LINE *l;
 366
 367         while (--nflush >= 0) {
 368                 l = lines;
 369                 lines = l->l_next;
 370                 if (l->l_line) {
 371                         flush_blanks();
 372                         flush_line(l);
 373                 }
 374                 if (l->l_line || l->l_next)
 375                         nblank_lines++;
 376                 if (l->l_line)
 377                         (void)free(l->l_line);
 378                 free_line(l);
 379         }
 380         if (lines)
 381                 lines->l_prev = NULL;
 382 }
 383
 384 /*
 385  * Print a number of newline/half newlines.  If fine flag is set, nblank_lines
 386  * is the number of half line feeds, otherwise it is the number of whole line
 387  * feeds.
 388  */
 389 static void
 390 flush_blanks(void)
 391 {
 392         int half, i, nb;
 393
 394         half = 0;
 395         nb = nblank_lines;
 396         if (nb & 1) {
 397                 if (fine)
 398                         half = 1;
 399                 else
 400                         nb++;
 401         }
 402         nb /= 2;
 403         for (i = nb; --i >= 0;)
 404                 PUTC('\n');
 405         if (half) {
 406                 PUTC(ESC);
 407                 PUTC(FHLF);
 408                 if (!nb)
 409                         PUTC('\r');
 410         }
 411         nblank_lines = 0;
 412 }
 413
 414 /*
 415  * Write a line to stdout taking care of space to tab conversion (-h flag)
 416  * and character set shifts.
 417  */
 418 static void
 419 flush_line(LINE *l)
 420 {
 421         CHAR *c, *endc;
 422         int i, j, nchars, last_col, save, this_col, tot;
 423
 424         last_col = 0;
 425         nchars = l->l_line_len;
 426
 427         if (l->l_needs_sort) {
 428                 static CHAR *sorted;
 429                 static int count_size, *count, sorted_size;
 430
 431                 /*
 432                  * Do an O(n) sort on l->l_line by column being careful to
 433                  * preserve the order of characters in the same column.
 434                  */
 435                 if (l->l_lsize > sorted_size) {
 436                         sorted_size = l->l_lsize;
 437                         if ((sorted = realloc(sorted,
 438                             (unsigned)sizeof(CHAR) * sorted_size)) == NULL)
 439                                 err(1, NULL);
 440                 }
 441                 if (l->l_max_col >= count_size) {
 442                         count_size = l->l_max_col + 1;
 443                         if ((count = realloc(count,
 444                             (unsigned)sizeof(int) * count_size)) == NULL)
 445                                 err(1, NULL);
 446                 }
 447                 memset(count, 0, sizeof(int) * l->l_max_col + 1);
 448                 for (i = nchars, c = l->l_line; --i >= 0; c++)
 449                         count[c->c_column]++;
 450
 451                 /*
 452                  * calculate running total (shifted down by 1) to use as
 453                  * indices into new line.
 454                  */
 455                 for (tot = 0, i = 0; i <= l->l_max_col; i++) {
 456                         save = count[i];
 457                         count[i] = tot;
 458                         tot += save;
 459                 }
 460
 461                 for (i = nchars, c = l->l_line; --i >= 0; c++)
 462                         sorted[count[c->c_column]++] = *c;
 463                 c = sorted;
 464         } else
 465                 c = l->l_line;
 466         while (nchars > 0) {
 467                 this_col = c->c_column;
 468                 endc = c;
 469                 do {
 470                         ++endc;
 471                 } while (--nchars > 0 && this_col == endc->c_column);
 472
 473                 /* if -b only print last character */
 474                 if (no_backspaces) {
 475                         c = endc - 1;
 476                         if (nchars > 0 &&
 477                             this_col + c->c_width > endc->c_column)
 478                                 continue;
 479                 }
 480
 481                 if (this_col > last_col) {
 482                         int nspace = this_col - last_col;
 483
 484                         if (compress_spaces && nspace > 1) {
 485                                 while (1) {
 486                                         int tab_col, tab_size;
 487
 488                                         tab_col = (last_col + 8) & ~7;
 489                                         if (tab_col > this_col)
 490                                                 break;
 491                                         tab_size = tab_col - last_col;
 492                                         if (tab_size == 1)
 493                                                 PUTC(' ');
 494                                         else
 495                                                 PUTC('\t');
 496                                         nspace -= tab_size;
 497                                         last_col = tab_col;
 498                                 }
 499                         }
 500                         while (--nspace >= 0)
 501                                 PUTC(' ');
 502                         last_col = this_col;
 503                 }
 504
 505                 for (;;) {
 506                         if (c->c_set != last_set) {
 507                                 switch (c->c_set) {
 508                                 case CS_NORMAL:
 509                                         PUTC(SI);
 510                                         break;
 511                                 case CS_ALTERNATE:
 512                                         PUTC(SO);
 513                                 }
 514                                 last_set = c->c_set;
 515                         }
 516                         PUTC(c->c_char);
 517                         if ((c + 1) < endc)
 518                                 for (j = 0; j < c->c_width; j++)
 519                                         PUTC('\b');
 520                         if (++c >= endc)
 521                                 break;
 522                 }
 523                 last_col += (c - 1)->c_width;
 524         }
 525 }
 526
 527 /*
 528  * Increment or decrement a line number, checking for overflow.
 529  * Stop one below INT_MAX such that the adjust variable is safe.
 530  */
 531 void
 532 addto_lineno(int *lno, int offset)
 533 {
 534         if (offset > 0) {
 535                 if (*lno >= INT_MAX - offset)
 536                         errx(1, "too many lines");
 537         } else {
 538                 if (*lno < INT_MIN - offset)
 539                         errx(1, "too many reverse line feeds");
 540         }
 541         *lno += offset;
 542 }
 543
 544 #define NALLOC 64
 545
 546 static LINE *line_freelist;
 547
 548 static LINE *
 549 alloc_line(void)
 550 {
 551         LINE *l;
 552         int i;
 553
 554         if (!line_freelist) {
 555                 if ((l = realloc(NULL, sizeof(LINE) * NALLOC)) == NULL)
 556                         err(1, NULL);
 557                 line_freelist = l;
 558                 for (i = 1; i < NALLOC; i++, l++)
 559                         l->l_next = l + 1;
 560                 l->l_next = NULL;
 561         }
 562         l = line_freelist;
 563         line_freelist = l->l_next;
 564
 565         memset(l, 0, sizeof(LINE));
 566         return (l);
 567 }
 568
 569 static void
 570 free_line(LINE *l)
 571 {
 572
 573         l->l_next = line_freelist;
 574         line_freelist = l;
 575 }
 576
 577 static void
 578 usage(void)
 579 {
 580
 581         (void)fprintf(stderr, "usage: col [-bfhpx] [-l nline]\n");
 582         exit(1);
 583 }
 584
 585 static void
 586 dowarn(int line)
 587 {
 588
 589         warnx("warning: can't back up %s",
 590                 line < 0 ? "past first line" : "-- line already flushed");
 591 }