1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 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/capsicum.h> 36 37 #include <capsicum_helpers.h> 38 #include <err.h> 39 #include <errno.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 (void)setlocale(LC_CTYPE, ""); 128 129 if (caph_limit_stdio() == -1) 130 err(1, "unable to limit stdio"); 131 132 if (caph_enter() < 0) 133 err(1, "unable to enter capability mode"); 134 135 max_bufd_lines = 256; 136 compress_spaces = 1; /* compress spaces into tabs */ 137 while ((opt = getopt(argc, argv, "bfhl:px")) != -1) 138 switch (opt) { 139 case 'b': /* do not output backspaces */ 140 no_backspaces = 1; 141 break; 142 case 'f': /* allow half forward line feeds */ 143 fine = 1; 144 break; 145 case 'h': /* compress spaces into tabs */ 146 compress_spaces = 1; 147 break; 148 case 'l': /* buffered line count */ 149 max_bufd_lines = strtonum(optarg, 1, 150 (INT_MAX - BUFFER_MARGIN) / 2, &errstr) * 2; 151 if (errstr != NULL) 152 errx(1, "bad -l argument, %s: %s", errstr, 153 optarg); 154 break; 155 case 'p': /* pass unknown control sequences */ 156 pass_unknown_seqs = 1; 157 break; 158 case 'x': /* do not compress spaces into tabs */ 159 compress_spaces = 0; 160 break; 161 case '?': 162 default: 163 usage(); 164 } 165 166 if (optind != argc) 167 usage(); 168 169 adjust = cur_col = extra_lines = warned = 0; 170 cur_line = max_line = nflushd_lines = this_line = 0; 171 cur_set = last_set = CS_NORMAL; 172 lines = l = alloc_line(); 173 174 while ((ch = getwchar()) != WEOF) { 175 if (!iswgraph(ch)) { 176 switch (ch) { 177 case BS: /* can't go back further */ 178 if (cur_col == 0) 179 continue; 180 --cur_col; 181 continue; 182 case CR: 183 cur_col = 0; 184 continue; 185 case ESC: /* just ignore EOF */ 186 switch(getwchar()) { 187 /* 188 * In the input stream, accept both the 189 * XPG5 sequences ESC-digit and the 190 * traditional BSD sequences ESC-ctrl. 191 */ 192 case '\007': 193 /* FALLTHROUGH */ 194 case RLF: 195 addto_lineno(&cur_line, -2); 196 break; 197 case '\010': 198 /* FALLTHROUGH */ 199 case RHLF: 200 addto_lineno(&cur_line, -1); 201 break; 202 case '\011': 203 /* FALLTHROUGH */ 204 case FHLF: 205 addto_lineno(&cur_line, 1); 206 if (cur_line > max_line) 207 max_line = cur_line; 208 } 209 continue; 210 case NL: 211 addto_lineno(&cur_line, 2); 212 if (cur_line > max_line) 213 max_line = cur_line; 214 cur_col = 0; 215 continue; 216 case SPACE: 217 ++cur_col; 218 continue; 219 case SI: 220 cur_set = CS_NORMAL; 221 continue; 222 case SO: 223 cur_set = CS_ALTERNATE; 224 continue; 225 case TAB: /* adjust column */ 226 cur_col |= 7; 227 ++cur_col; 228 continue; 229 case VT: 230 addto_lineno(&cur_line, -2); 231 continue; 232 } 233 if (iswspace(ch)) { 234 if ((width = wcwidth(ch)) > 0) 235 cur_col += width; 236 continue; 237 } 238 if (!pass_unknown_seqs) 239 continue; 240 } 241 242 /* Must stuff ch in a line - are we at the right one? */ 243 if (cur_line + adjust != this_line) { 244 LINE *lnew; 245 246 /* round up to next line */ 247 adjust = !fine && (cur_line & 1); 248 249 if (cur_line + adjust < this_line) { 250 while (cur_line + adjust < this_line && 251 l->l_prev != NULL) { 252 l = l->l_prev; 253 this_line--; 254 } 255 if (cur_line + adjust < this_line) { 256 if (nflushd_lines == 0) { 257 /* 258 * Allow backup past first 259 * line if nothing has been 260 * flushed yet. 261 */ 262 while (cur_line + adjust 263 < this_line) { 264 lnew = alloc_line(); 265 l->l_prev = lnew; 266 lnew->l_next = l; 267 l = lines = lnew; 268 extra_lines++; 269 this_line--; 270 } 271 } else { 272 if (!warned++) 273 dowarn(cur_line); 274 cur_line = this_line - adjust; 275 } 276 } 277 } else { 278 /* may need to allocate here */ 279 while (cur_line + adjust > this_line) { 280 if (l->l_next == NULL) { 281 l->l_next = alloc_line(); 282 l->l_next->l_prev = l; 283 } 284 l = l->l_next; 285 this_line++; 286 } 287 } 288 if (this_line > nflushd_lines && 289 this_line - nflushd_lines >= 290 max_bufd_lines + BUFFER_MARGIN) { 291 if (extra_lines) { 292 flush_lines(extra_lines); 293 extra_lines = 0; 294 } 295 flush_lines(this_line - nflushd_lines - 296 max_bufd_lines); 297 nflushd_lines = this_line - max_bufd_lines; 298 } 299 } 300 /* grow line's buffer? */ 301 if (l->l_line_len + 1 >= l->l_lsize) { 302 int need; 303 304 need = l->l_lsize ? l->l_lsize * 2 : 90; 305 if ((l->l_line = realloc(l->l_line, 306 (unsigned)need * sizeof(CHAR))) == NULL) 307 err(1, NULL); 308 l->l_lsize = need; 309 } 310 c = &l->l_line[l->l_line_len++]; 311 c->c_char = ch; 312 c->c_set = cur_set; 313 c->c_column = cur_col; 314 c->c_width = wcwidth(ch); 315 /* 316 * If things are put in out of order, they will need sorting 317 * when it is flushed. 318 */ 319 if (cur_col < l->l_max_col) 320 l->l_needs_sort = 1; 321 else 322 l->l_max_col = cur_col; 323 if (c->c_width > 0) 324 cur_col += c->c_width; 325 } 326 if (ferror(stdin)) 327 err(1, NULL); 328 if (extra_lines) { 329 /* 330 * Extra lines only exist if no lines have been flushed 331 * yet. This means that 'lines' must point to line zero 332 * after we flush the extra lines. 333 */ 334 flush_lines(extra_lines); 335 l = lines; 336 this_line = 0; 337 } 338 339 /* goto the last line that had a character on it */ 340 for (; l->l_next; l = l->l_next) 341 this_line++; 342 flush_lines(this_line - nflushd_lines + 1); 343 344 /* make sure we leave things in a sane state */ 345 if (last_set != CS_NORMAL) 346 PUTC(SI); 347 348 /* flush out the last few blank lines */ 349 if (max_line >= this_line) 350 nblank_lines = max_line - this_line + (max_line & 1); 351 if (nblank_lines == 0) 352 /* end with a newline even if the source doesn't */ 353 nblank_lines = 2; 354 flush_blanks(); 355 exit(0); 356 } 357 358 /* 359 * Prints the first 'nflush' lines. Printed lines are freed. 360 * After this function returns, 'lines' points to the first 361 * of the remaining lines, and 'nblank_lines' will have the 362 * number of half line feeds between the final flushed line 363 * and the first remaining line. 364 */ 365 static void 366 flush_lines(int nflush) 367 { 368 LINE *l; 369 370 while (--nflush >= 0) { 371 l = lines; 372 lines = l->l_next; 373 if (l->l_line) { 374 flush_blanks(); 375 flush_line(l); 376 free(l->l_line); 377 } 378 if (l->l_next) 379 nblank_lines++; 380 free_line(l); 381 } 382 if (lines) 383 lines->l_prev = NULL; 384 } 385 386 /* 387 * Print a number of newline/half newlines. 388 * nblank_lines is the number of half line feeds. 389 */ 390 static void 391 flush_blanks(void) 392 { 393 int half, i, nb; 394 395 half = 0; 396 nb = nblank_lines; 397 if (nb & 1) { 398 if (fine) 399 half = 1; 400 else 401 nb++; 402 } 403 nb /= 2; 404 for (i = nb; --i >= 0;) 405 PUTC('\n'); 406 if (half) { 407 PUTC(ESC); 408 PUTC(FHLF); 409 if (!nb) 410 PUTC('\r'); 411 } 412 nblank_lines = 0; 413 } 414 415 /* 416 * Write a line to stdout taking care of space to tab conversion (-h flag) 417 * and character set shifts. 418 */ 419 static void 420 flush_line(LINE *l) 421 { 422 CHAR *c, *endc; 423 int i, j, nchars, last_col, save, this_col, tot; 424 425 last_col = 0; 426 nchars = l->l_line_len; 427 428 if (l->l_needs_sort) { 429 static CHAR *sorted; 430 static int count_size, *count, sorted_size; 431 432 /* 433 * Do an O(n) sort on l->l_line by column being careful to 434 * preserve the order of characters in the same column. 435 */ 436 if (l->l_lsize > sorted_size) { 437 sorted_size = l->l_lsize; 438 if ((sorted = realloc(sorted, 439 (unsigned)sizeof(CHAR) * sorted_size)) == NULL) 440 err(1, NULL); 441 } 442 if (l->l_max_col >= count_size) { 443 count_size = l->l_max_col + 1; 444 if ((count = realloc(count, 445 (unsigned)sizeof(int) * count_size)) == NULL) 446 err(1, NULL); 447 } 448 memset(count, 0, sizeof(int) * l->l_max_col + 1); 449 for (i = nchars, c = l->l_line; --i >= 0; c++) 450 count[c->c_column]++; 451 452 /* 453 * calculate running total (shifted down by 1) to use as 454 * indices into new line. 455 */ 456 for (tot = 0, i = 0; i <= l->l_max_col; i++) { 457 save = count[i]; 458 count[i] = tot; 459 tot += save; 460 } 461 462 for (i = nchars, c = l->l_line; --i >= 0; c++) 463 sorted[count[c->c_column]++] = *c; 464 c = sorted; 465 } else 466 c = l->l_line; 467 while (nchars > 0) { 468 this_col = c->c_column; 469 endc = c; 470 do { 471 ++endc; 472 } while (--nchars > 0 && this_col == endc->c_column); 473 474 /* if -b only print last character */ 475 if (no_backspaces) { 476 c = endc - 1; 477 if (nchars > 0 && 478 this_col + c->c_width > endc->c_column) 479 continue; 480 } 481 482 if (this_col > last_col) { 483 int nspace = this_col - last_col; 484 485 if (compress_spaces && nspace > 1) { 486 while (1) { 487 int tab_col, tab_size; 488 489 tab_col = (last_col + 8) & ~7; 490 if (tab_col > this_col) 491 break; 492 tab_size = tab_col - last_col; 493 if (tab_size == 1) 494 PUTC(' '); 495 else 496 PUTC('\t'); 497 nspace -= tab_size; 498 last_col = tab_col; 499 } 500 } 501 while (--nspace >= 0) 502 PUTC(' '); 503 last_col = this_col; 504 } 505 506 for (;;) { 507 if (c->c_set != last_set) { 508 switch (c->c_set) { 509 case CS_NORMAL: 510 PUTC(SI); 511 break; 512 case CS_ALTERNATE: 513 PUTC(SO); 514 } 515 last_set = c->c_set; 516 } 517 PUTC(c->c_char); 518 if ((c + 1) < endc) 519 for (j = 0; j < c->c_width; j++) 520 PUTC('\b'); 521 if (++c >= endc) 522 break; 523 } 524 last_col += (c - 1)->c_width; 525 } 526 } 527 528 /* 529 * Increment or decrement a line number, checking for overflow. 530 * Stop one below INT_MAX such that the adjust variable is safe. 531 */ 532 void 533 addto_lineno(int *lno, int offset) 534 { 535 if (offset > 0) { 536 if (*lno >= INT_MAX - offset) 537 errx(1, "too many lines"); 538 } else { 539 if (*lno < INT_MIN - offset) 540 errx(1, "too many reverse line feeds"); 541 } 542 *lno += offset; 543 } 544 545 #define NALLOC 64 546 547 static LINE *line_freelist; 548 549 static LINE * 550 alloc_line(void) 551 { 552 LINE *l; 553 int i; 554 555 if (!line_freelist) { 556 if ((l = realloc(NULL, sizeof(LINE) * NALLOC)) == NULL) 557 err(1, NULL); 558 line_freelist = l; 559 for (i = 1; i < NALLOC; i++, l++) 560 l->l_next = l + 1; 561 l->l_next = NULL; 562 } 563 l = line_freelist; 564 line_freelist = l->l_next; 565 566 memset(l, 0, sizeof(LINE)); 567 return (l); 568 } 569 570 static void 571 free_line(LINE *l) 572 { 573 574 l->l_next = line_freelist; 575 line_freelist = l; 576 } 577 578 static void 579 usage(void) 580 { 581 582 (void)fprintf(stderr, "usage: col [-bfhpx] [-l nline]\n"); 583 exit(1); 584 } 585 586 static void 587 dowarn(int line) 588 { 589 590 warnx("warning: can't back up %s", 591 line < 0 ? "past first line" : "-- line already flushed"); 592 } 593