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: head/usr.bin/col/col.c 282722 2015-05-10 11:41:38Z bapt $
  35  */
  36
  37 #include <err.h>
  38 #include <errno.h>
  39 #include <limits.h>
  40 #include <locale.h>
  41 #include <stdio.h>
  42 #include <stdlib.h>
  43 #include <string.h>
  44 #include <termios.h>
  45 #include <unistd.h>
  46 #include <wchar.h>
  47 #include <wctype.h>
  48
  49 #define BS      '\b'            /* backspace */
  50 #define TAB     '\t'            /* tab */
  51 #define SPACE   ' '             /* space */
  52 #define NL      '\n'            /* newline */
  53 #define CR      '\r'            /* carriage return */
  54 #define ESC     '\033'          /* escape */
  55 #define SI      '\017'          /* shift in to normal character set */
  56 #define SO      '\016'          /* shift out to alternate character set */
  57 #define VT      '\013'          /* vertical tab (aka reverse line feed) */
  58 #define RLF     '7'             /* ESC-7 reverse line feed */
  59 #define RHLF    '8'             /* ESC-8 reverse half-line feed */
  60 #define FHLF    '9'             /* ESC-9 forward half-line feed */
  61
  62 /* build up at least this many lines before flushing them out */
  63 #define BUFFER_MARGIN           32
  64
  65 typedef char CSET;
  66
  67 typedef struct char_str {
  68 #define CS_NORMAL       1
  69 #define CS_ALTERNATE    2
  70         short           c_column;       /* column character is in */
  71         CSET            c_set;          /* character set (currently only 2) */
  72         wchar_t         c_char;         /* character in question */
  73         int             c_width;        /* character width */
  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 static void     addto_lineno(int *, int);
  88 static LINE    *alloc_line(void);
  89 static void     dowarn(int);
  90 static void     flush_line(LINE *);
  91 static void     flush_lines(int);
  92 static void     flush_blanks(void);
  93 static void     free_line(LINE *);
  94 static void     usage(void);
  95
  96 static CSET     last_set;               /* char_set of last char printed */
  97 static LINE    *lines;
  98 static int      compress_spaces;        /* if doing space -> tab conversion */
  99 static int      fine;                   /* if `fine' resolution (half lines) */
 100 static int      max_bufd_lines;         /* max # of half lines to keep in memory */
 101 static int      nblank_lines;           /* # blanks after last flushed line */
 102 static int      no_backspaces;          /* if not to output any backspaces */
 103 static int      pass_unknown_seqs;      /* pass unknown control sequences */
 104
 105 #define PUTC(ch) \
 106         do {                                    \
 107                 if (putwchar(ch) == WEOF)       \
 108                         errx(1, "write error"); \
 109         } while (0)
 110
 111 int
 112 main(int argc, char **argv)
 113 {
 114         wint_t 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, width;
 125         const char *errstr;
 126
 127         setlocale(LC_CTYPE, "");
 128
 129         max_bufd_lines = 256;
 130         compress_spaces = 1;            /* compress spaces into tabs */
 131         while ((opt = getopt(argc, argv, "bfhl:px")) != -1)
 132                 switch (opt) {
 133                 case 'b':               /* do not output backspaces */
 134                         no_backspaces = 1;
 135                         break;
 136                 case 'f':               /* allow half forward line feeds */
 137                         fine = 1;
 138                         break;
 139                 case 'h':               /* compress spaces into tabs */
 140                         compress_spaces = 1;
 141                         break;
 142                 case 'l':               /* buffered line count */
 143                         max_bufd_lines = strtonum(optarg, 1,
 144                             (INT_MAX - BUFFER_MARGIN) / 2, &errstr) * 2;
 145                         if (errstr != NULL)
 146                                 errx(1, "bad -l argument, %s: %s", errstr,
 147                                         optarg);
 148                         break;
 149                 case 'p':               /* pass unknown control sequences */
 150                         pass_unknown_seqs = 1;
 151                         break;
 152                 case 'x':               /* do not compress spaces into tabs */
 153                         compress_spaces = 0;
 154                         break;
 155                 case '?':
 156                 default:
 157                         usage();
 158                 }
 159
 160         if (optind != argc)
 161                 usage();
 162
 163         adjust = cur_col = extra_lines = warned = 0;
 164         cur_line = max_line = nflushd_lines = this_line = 0;
 165         cur_set = last_set = CS_NORMAL;
 166         lines = l = alloc_line();
 167
 168         while ((ch = getwchar()) != WEOF) {
 169                 if (!iswgraph(ch)) {
 170                         switch (ch) {
 171                         case BS:                /* can't go back further */
 172                                 if (cur_col == 0)
 173                                         continue;
 174                                 --cur_col;
 175                                 continue;
 176                         case CR:
 177                                 cur_col = 0;
 178                                 continue;
 179                         case ESC:               /* just ignore EOF */
 180                                 switch (getwchar()) {
 181                                 /*
 182                                  * In the input stream, accept both the
 183                                  * XPG5 sequences ESC-digit and the
 184                                  * traditional BSD sequences ESC-ctrl.
 185                                  */
 186                                 case '\007':
 187                                         /* FALLTHROUGH */
 188                                 case RLF:
 189                                         addto_lineno(&cur_line, -2);
 190                                         break;
 191                                 case '\010':
 192                                         /* FALLTHROUGH */
 193                                 case RHLF:
 194                                         addto_lineno(&cur_line, -1);
 195                                         break;
 196                                 case '\011':
 197                                         /* FALLTHROUGH */
 198                                 case FHLF:
 199                                         addto_lineno(&cur_line, 1);
 200                                         if (cur_line > max_line)
 201                                                 max_line = cur_line;
 202                                 }
 203                                 continue;
 204                         case NL:
 205                                 addto_lineno(&cur_line, 2);
 206                                 if (cur_line > max_line)
 207                                         max_line = cur_line;
 208                                 cur_col = 0;
 209                                 continue;
 210                         case SPACE:
 211                                 ++cur_col;
 212                                 continue;
 213                         case SI:
 214                                 cur_set = CS_NORMAL;
 215                                 continue;
 216                         case SO:
 217                                 cur_set = CS_ALTERNATE;
 218                                 continue;
 219                         case TAB:               /* adjust column */
 220                                 cur_col |= 7;
 221                                 ++cur_col;
 222                                 continue;
 223                         case VT:
 224                                 addto_lineno(&cur_line, -2);
 225                                 continue;
 226                         }
 227                         if (iswspace(ch)) {
 228                                 if ((width = wcwidth(ch)) > 0)
 229                                         cur_col += width;
 230                                 continue;
 231                         }
 232                         if (!pass_unknown_seqs)
 233                                 continue;
 234                 }
 235
 236                 /* Must stuff ch in a line - are we at the right one? */
 237                 if (cur_line + adjust != this_line) {
 238                         LINE *lnew;
 239
 240                         /* round up to next line */
 241                         adjust = !fine && (cur_line & 1);
 242
 243                         if (cur_line + adjust < this_line) {
 244                                 while (cur_line + adjust < this_line &&
 245                                     l->l_prev != NULL) {
 246                                         l = l->l_prev;
 247                                         this_line--;
 248                                 }
 249                                 if (cur_line + adjust < this_line) {
 250                                         if (nflushd_lines == 0) {
 251                                                 /*
 252                                                  * Allow backup past first
 253                                                  * line if nothing has been
 254                                                  * flushed yet.
 255                                                  */
 256                                                 while (cur_line + adjust
 257                                                     < this_line) {
 258                                                         lnew = alloc_line();
 259                                                         l->l_prev = lnew;
 260                                                         lnew->l_next = l;
 261                                                         l = lines = lnew;
 262                                                         extra_lines++;
 263                                                         this_line--;
 264                                                 }
 265                                         } else {
 266                                                 if (!warned++)
 267                                                         dowarn(cur_line);
 268                                                 cur_line = this_line - adjust;
 269                                         }
 270                                 }
 271                         } else {
 272                                 /* may need to allocate here */
 273                                 while (cur_line + adjust > this_line) {
 274                                         if (l->l_next == NULL) {
 275                                                 l->l_next = alloc_line();
 276                                                 l->l_next->l_prev = l;
 277                                         }
 278                                         l = l->l_next;
 279                                         this_line++;
 280                                 }
 281                         }
 282                         if (this_line > nflushd_lines &&
 283                             this_line - nflushd_lines >=
 284                             max_bufd_lines + BUFFER_MARGIN) {
 285                                 if (extra_lines) {
 286                                         flush_lines(extra_lines);
 287                                         extra_lines = 0;
 288                                 }
 289                                 flush_lines(this_line - nflushd_lines -
 290                                     max_bufd_lines);
 291                                 nflushd_lines = this_line - max_bufd_lines;
 292                         }
 293                 }
 294                 /* grow line's buffer? */
 295                 if (l->l_line_len + 1 >= l->l_lsize) {
 296                         int need;
 297
 298                         need = l->l_lsize ? l->l_lsize * 2 : 90;
 299                         if ((l->l_line = realloc(l->l_line,
 300                             (unsigned)need * sizeof(CHAR))) == NULL)
 301                                 err(1, NULL);
 302                         l->l_lsize = need;
 303                 }
 304                 c = &l->l_line[l->l_line_len++];
 305                 c->c_char = ch;
 306                 c->c_set = cur_set;
 307                 c->c_column = cur_col;
 308                 c->c_width = wcwidth(ch);
 309                 /*
 310                  * If things are put in out of order, they will need sorting
 311                  * when it is flushed.
 312                  */
 313                 if (cur_col < l->l_max_col)
 314                         l->l_needs_sort = 1;
 315                 else
 316                         l->l_max_col = cur_col;
 317                 if (c->c_width > 0)
 318                         cur_col += c->c_width;
 319         }
 320         if (ferror(stdin))
 321                 err(1, NULL);
 322         if (extra_lines)
 323                 flush_lines(extra_lines);
 324
 325         /* goto the last line that had a character on it */
 326         for (; l->l_next; l = l->l_next)
 327                 this_line++;
 328         flush_lines(this_line - nflushd_lines + 1);
 329
 330         /* make sure we leave things in a sane state */
 331         if (last_set != CS_NORMAL)
 332                 PUTC(SI);
 333
 334         /* flush out the last few blank lines */
 335         if (max_line > this_line)
 336                 nblank_lines = max_line - this_line;
 337         if (max_line & 1)
 338                 nblank_lines++;
 339         flush_blanks();
 340         exit(0);
 341 }
 342
 343 static void
 344 flush_lines(int nflush)
 345 {
 346         LINE *l;
 347
 348         while (--nflush >= 0) {
 349                 l = lines;
 350                 lines = l->l_next;
 351                 if (l->l_line) {
 352                         flush_blanks();
 353                         flush_line(l);
 354                 }
 355                 if (l->l_line || l->l_next)
 356                         nblank_lines++;
 357                 if (l->l_line)
 358                         free(l->l_line);
 359                 free_line(l);
 360         }
 361         if (lines)
 362                 lines->l_prev = NULL;
 363 }
 364
 365 /*
 366  * Print a number of newline/half newlines.  If fine flag is set, nblank_lines
 367  * is the number of half line feeds, otherwise it is the number of whole line
 368  * feeds.
 369  */
 370 static void
 371 flush_blanks(void)
 372 {
 373         int half, i, nb;
 374
 375         half = 0;
 376         nb = nblank_lines;
 377         if (nb & 1) {
 378                 if (fine)
 379                         half = 1;
 380                 else
 381                         nb++;
 382         }
 383         nb /= 2;
 384         for (i = nb; --i >= 0;)
 385                 PUTC('\n');
 386         if (half) {
 387                 PUTC(ESC);
 388                 PUTC(FHLF);
 389                 if (!nb)
 390                         PUTC('\r');
 391         }
 392         nblank_lines = 0;
 393 }
 394
 395 /*
 396  * Write a line to stdout taking care of space to tab conversion (-h flag)
 397  * and character set shifts.
 398  */
 399 static void
 400 flush_line(LINE *l)
 401 {
 402         CHAR *c, *endc;
 403         int i, j, nchars, last_col, save, this_col, tot;
 404
 405         last_col = 0;
 406         nchars = l->l_line_len;
 407
 408         if (l->l_needs_sort) {
 409                 static CHAR *sorted;
 410                 static int count_size, *count, sorted_size;
 411
 412                 /*
 413                  * Do an O(n) sort on l->l_line by column being careful to
 414                  * preserve the order of characters in the same column.
 415                  */
 416                 if (l->l_lsize > sorted_size) {
 417                         sorted_size = l->l_lsize;
 418                         if ((sorted = realloc(sorted,
 419                             (unsigned)sizeof(CHAR) * sorted_size)) == NULL)
 420                                 err(1, NULL);
 421                 }
 422                 if (l->l_max_col >= count_size) {
 423                         count_size = l->l_max_col + 1;
 424                         if ((count = realloc(count,
 425                             (unsigned)sizeof(int) * count_size)) == NULL)
 426                                 err(1, NULL);
 427                 }
 428                 memset(count, 0, sizeof(int) * l->l_max_col + 1);
 429                 for (i = nchars, c = l->l_line; --i >= 0; c++)
 430                         count[c->c_column]++;
 431
 432                 /*
 433                  * calculate running total (shifted down by 1) to use as
 434                  * indices into new line.
 435                  */
 436                 for (tot = 0, i = 0; i <= l->l_max_col; i++) {
 437                         save = count[i];
 438                         count[i] = tot;
 439                         tot += save;
 440                 }
 441
 442                 for (i = nchars, c = l->l_line; --i >= 0; c++)
 443                         sorted[count[c->c_column]++] = *c;
 444                 c = sorted;
 445         } else
 446                 c = l->l_line;
 447         while (nchars > 0) {
 448                 this_col = c->c_column;
 449                 endc = c;
 450                 do {
 451                         ++endc;
 452                 } while (--nchars > 0 && this_col == endc->c_column);
 453
 454                 /* if -b only print last character */
 455                 if (no_backspaces) {
 456                         c = endc - 1;
 457                         if (nchars > 0 &&
 458                             this_col + c->c_width > endc->c_column)
 459                                 continue;
 460                 }
 461
 462                 if (this_col > last_col) {
 463                         int nspace = this_col - last_col;
 464
 465                         if (compress_spaces && nspace > 1) {
 466                                 while (1) {
 467                                         int tab_col, tab_size;
 468
 469                                         tab_col = (last_col + 8) & ~7;
 470                                         if (tab_col > this_col)
 471                                                 break;
 472                                         tab_size = tab_col - last_col;
 473                                         if (tab_size == 1)
 474                                                 PUTC(' ');
 475                                         else
 476                                                 PUTC('\t');
 477                                         nspace -= tab_size;
 478                                         last_col = tab_col;
 479                                 }
 480                         }
 481                         while (--nspace >= 0)
 482                                 PUTC(' ');
 483                         last_col = this_col;
 484                 }
 485
 486                 for (;;) {
 487                         if (c->c_set != last_set) {
 488                                 switch (c->c_set) {
 489                                 case CS_NORMAL:
 490                                         PUTC(SI);
 491                                         break;
 492                                 case CS_ALTERNATE:
 493                                         PUTC(SO);
 494                                 }
 495                                 last_set = c->c_set;
 496                         }
 497                         PUTC(c->c_char);
 498                         if ((c + 1) < endc)
 499                                 for (j = 0; j < c->c_width; j++)
 500                                         PUTC('\b');
 501                         if (++c >= endc)
 502                                 break;
 503                 }
 504                 last_col += (c - 1)->c_width;
 505         }
 506 }
 507
 508 /*
 509  * Increment or decrement a line number, checking for overflow.
 510  * Stop one below INT_MAX such that the adjust variable is safe.
 511  */
 512 void
 513 addto_lineno(int *lno, int offset)
 514 {
 515         if (offset > 0) {
 516                 if (*lno >= INT_MAX - offset)
 517                         errx(1, "too many lines");
 518         } else {
 519                 if (*lno < INT_MIN - offset)
 520                         errx(1, "too many reverse line feeds");
 521         }
 522         *lno += offset;
 523 }
 524
 525 #define NALLOC 64
 526
 527 static LINE *line_freelist;
 528
 529 static LINE *
 530 alloc_line(void)
 531 {
 532         LINE *l;
 533         int i;
 534
 535         if (!line_freelist) {
 536                 if ((l = realloc(NULL, sizeof(LINE) * NALLOC)) == NULL)
 537                         err(1, NULL);
 538                 line_freelist = l;
 539                 for (i = 1; i < NALLOC; i++, l++)
 540                         l->l_next = l + 1;
 541                 l->l_next = NULL;
 542         }
 543         l = line_freelist;
 544         line_freelist = l->l_next;
 545
 546         memset(l, 0, sizeof(LINE));
 547         return (l);
 548 }
 549
 550 static void
 551 free_line(LINE *l)
 552 {
 553
 554         l->l_next = line_freelist;
 555         line_freelist = l;
 556 }
 557
 558 static void
 559 usage(void)
 560 {
 561
 562         fprintf(stderr, "usage: col [-bfhpx] [-l nline]\n");
 563         exit(1);
 564 }
 565
 566 static void
 567 dowarn(int line)
 568 {
 569
 570         warnx("warning: can't back up %s",
 571                 line < 0 ? "past first line" : "-- line already flushed");
 572 }