1 /* $OpenBSD: process.c,v 1.5 1999/06/06 15:42:24 deraadt Exp $ */ 2 3 /*- 4 * Copyright (c) 1992 Diomidis Spinellis. 5 * Copyright (c) 1992, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * This code is derived from software contributed to Berkeley by 9 * Diomidis Spinellis of Imperial College, University of London. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the University of 22 * California, Berkeley and its contributors. 23 * 4. Neither the name of the University nor the names of its contributors 24 * may be used to endorse or promote products derived from this software 25 * without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 38 */ 39 40 #ifndef lint 41 /* from: static char sccsid[] = "@(#)process.c 8.1 (Berkeley) 6/6/93"; */ 42 static char *rcsid = "$OpenBSD: process.c,v 1.5 1999/06/06 15:42:24 deraadt Exp $"; 43 #endif /* not lint */ 44 45 #include <sys/types.h> 46 #include <sys/stat.h> 47 #include <sys/ioctl.h> 48 #include <sys/uio.h> 49 50 #include <ctype.h> 51 #include <errno.h> 52 #include <fcntl.h> 53 #include <limits.h> 54 #include <regex.h> 55 #include <stdio.h> 56 #include <stdlib.h> 57 #include <string.h> 58 #include <unistd.h> 59 60 #include "defs.h" 61 #include "extern.h" 62 63 static SPACE HS, PS, SS; 64 #define pd PS.deleted 65 #define ps PS.space 66 #define psl PS.len 67 #define hs HS.space 68 #define hsl HS.len 69 70 static inline int applies __P((struct s_command *)); 71 static void flush_appends __P((void)); 72 static void lputs __P((char *)); 73 static inline int regexec_e __P((regex_t *, const char *, int, int, size_t)); 74 static void regsub __P((SPACE *, char *, char *)); 75 static int substitute __P((struct s_command *)); 76 77 struct s_appends *appends; /* Array of pointers to strings to append. */ 78 static int appendx; /* Index into appends array. */ 79 int appendnum; /* Size of appends array. */ 80 81 static int lastaddr; /* Set by applies if last address of a range. */ 82 static int sdone; /* If any substitutes since last line input. */ 83 /* Iov structure for 'w' commands. */ 84 static regex_t *defpreg; 85 size_t maxnsub; 86 regmatch_t *match; 87 88 #define OUT(s) { fwrite(s, sizeof(u_char), psl, stdout); } 89 90 void 91 process() 92 { 93 struct s_command *cp; 94 SPACE tspace; 95 size_t len, oldpsl; 96 char *p; 97 98 for (linenum = 0; mf_fgets(&PS, REPLACE);) { 99 pd = 0; 100 top: 101 cp = prog; 102 redirect: 103 while (cp != NULL) { 104 if (!applies(cp)) { 105 cp = cp->next; 106 continue; 107 } 108 switch (cp->code) { 109 case '{': 110 cp = cp->u.c; 111 goto redirect; 112 case 'a': 113 if (appendx >= appendnum) 114 appends = xrealloc(appends, 115 sizeof(struct s_appends) * 116 (appendnum *= 2)); 117 appends[appendx].type = AP_STRING; 118 appends[appendx].s = cp->t; 119 appends[appendx].len = strlen(cp->t); 120 appendx++; 121 break; 122 case 'b': 123 cp = cp->u.c; 124 goto redirect; 125 case 'c': 126 pd = 1; 127 psl = 0; 128 if (cp->a2 == NULL || lastaddr) 129 (void)printf("%s", cp->t); 130 break; 131 case 'd': 132 pd = 1; 133 goto new; 134 case 'D': 135 if (pd) 136 goto new; 137 if ((p = memchr(ps, '\n', psl - 1)) == NULL) { 138 pd = 1; 139 goto new; 140 } else { 141 psl -= (p + 1) - ps; 142 memmove(ps, p + 1, psl); 143 goto top; 144 } 145 case 'g': 146 cspace(&PS, hs, hsl, REPLACE); 147 break; 148 case 'G': 149 if (hs == NULL) 150 cspace(&HS, "\n", 1, REPLACE); 151 cspace(&PS, hs, hsl, 0); 152 break; 153 case 'h': 154 cspace(&HS, ps, psl, REPLACE); 155 break; 156 case 'H': 157 cspace(&HS, ps, psl, 0); 158 break; 159 case 'i': 160 (void)printf("%s", cp->t); 161 break; 162 case 'l': 163 lputs(ps); 164 break; 165 case 'n': 166 if (!nflag && !pd) 167 OUT(ps) 168 flush_appends(); 169 if (!mf_fgets(&PS, REPLACE)) 170 exit(0); 171 pd = 0; 172 break; 173 case 'N': 174 flush_appends(); 175 if (!mf_fgets(&PS, 0)) { 176 if (!nflag && !pd) 177 OUT(ps) 178 exit(0); 179 } 180 break; 181 case 'p': 182 if (pd) 183 break; 184 OUT(ps) 185 break; 186 case 'P': 187 if (pd) 188 break; 189 if ((p = memchr(ps, '\n', psl - 1)) != NULL) { 190 oldpsl = psl; 191 psl = (p + 1) - ps; 192 } 193 OUT(ps) 194 if (p != NULL) 195 psl = oldpsl; 196 break; 197 case 'q': 198 if (!nflag && !pd) 199 OUT(ps) 200 flush_appends(); 201 exit(0); 202 case 'r': 203 if (appendx >= appendnum) 204 appends = xrealloc(appends, 205 sizeof(struct s_appends) * 206 (appendnum *= 2)); 207 appends[appendx].type = AP_FILE; 208 appends[appendx].s = cp->t; 209 appends[appendx].len = strlen(cp->t); 210 appendx++; 211 break; 212 case 's': 213 sdone |= substitute(cp); 214 break; 215 case 't': 216 if (sdone) { 217 sdone = 0; 218 cp = cp->u.c; 219 goto redirect; 220 } 221 break; 222 case 'w': 223 if (pd) 224 break; 225 if (cp->u.fd == -1 && (cp->u.fd = open(cp->t, 226 O_WRONLY|O_APPEND|O_CREAT|O_TRUNC, 227 DEFFILEMODE)) == -1) 228 err(FATAL, "%s: %s\n", 229 cp->t, strerror(errno)); 230 if (write(cp->u.fd, ps, psl) != psl) 231 err(FATAL, "%s: %s\n", 232 cp->t, strerror(errno)); 233 break; 234 case 'x': 235 if (hs == NULL) 236 cspace(&HS, "\n", 1, REPLACE); 237 tspace = PS; 238 PS = HS; 239 HS = tspace; 240 break; 241 case 'y': 242 if (pd) 243 break; 244 for (p = ps, len = psl; --len; ++p) 245 *p = cp->u.y[(unsigned char)*p]; 246 break; 247 case ':': 248 case '}': 249 break; 250 case '=': 251 (void)printf("%lu\n", linenum); 252 } 253 cp = cp->next; 254 } /* for all cp */ 255 256 new: if (!nflag && !pd) 257 OUT(ps) 258 flush_appends(); 259 } /* for all lines */ 260 } 261 262 /* 263 * TRUE if the address passed matches the current program state 264 * (lastline, linenumber, ps). 265 */ 266 #define MATCH(a) \ 267 (a)->type == AT_RE ? regexec_e((a)->u.r, ps, 0, 1, psl) : \ 268 (a)->type == AT_LINE ? linenum == (a)->u.l : lastline 269 270 /* 271 * Return TRUE if the command applies to the current line. Sets the inrange 272 * flag to process ranges. Interprets the non-select (``!'') flag. 273 */ 274 static inline int 275 applies(cp) 276 struct s_command *cp; 277 { 278 int r; 279 280 lastaddr = 0; 281 if (cp->a1 == NULL && cp->a2 == NULL) 282 r = 1; 283 else if (cp->a2) 284 if (cp->inrange) { 285 if (MATCH(cp->a2)) { 286 cp->inrange = 0; 287 lastaddr = 1; 288 } 289 r = 1; 290 } else if (MATCH(cp->a1)) { 291 /* 292 * If the second address is a number less than or 293 * equal to the line number first selected, only 294 * one line shall be selected. 295 * -- POSIX 1003.2 296 */ 297 if (cp->a2->type == AT_LINE && 298 linenum >= cp->a2->u.l) 299 lastaddr = 1; 300 else 301 cp->inrange = 1; 302 r = 1; 303 } else 304 r = 0; 305 else 306 r = MATCH(cp->a1); 307 return (cp->nonsel ? ! r : r); 308 } 309 310 /* 311 * substitute -- 312 * Do substitutions in the pattern space. Currently, we build a 313 * copy of the new pattern space in the substitute space structure 314 * and then swap them. 315 */ 316 static int 317 substitute(cp) 318 struct s_command *cp; 319 { 320 SPACE tspace; 321 regex_t *re; 322 size_t re_off, slen; 323 int n, lastempty; 324 char *s; 325 326 s = ps; 327 re = cp->u.s->re; 328 if (re == NULL) { 329 if (defpreg != NULL && cp->u.s->maxbref > defpreg->re_nsub) { 330 linenum = cp->u.s->linenum; 331 err(COMPILE, "\\%d not defined in the RE", 332 cp->u.s->maxbref); 333 } 334 } 335 if (!regexec_e(re, s, 0, 0, psl)) 336 return (0); 337 338 SS.len = 0; /* Clean substitute space. */ 339 slen = psl; 340 n = cp->u.s->n; 341 lastempty = 1; 342 343 switch (n) { 344 case 0: /* Global */ 345 do { 346 if (lastempty || match[0].rm_so != match[0].rm_eo) { 347 /* Locate start of replaced string. */ 348 re_off = match[0].rm_so; 349 /* Copy leading retained string. */ 350 cspace(&SS, s, re_off, APPEND); 351 /* Add in regular expression. */ 352 regsub(&SS, s, cp->u.s->new); 353 } 354 355 /* Move past this match. */ 356 if (match[0].rm_so != match[0].rm_eo) { 357 s += match[0].rm_eo; 358 slen -= match[0].rm_eo; 359 lastempty = 0; 360 } else { 361 if (match[0].rm_so == 0) 362 cspace(&SS, s, match[0].rm_so + 1, 363 APPEND); 364 else 365 cspace(&SS, s + match[0].rm_so, 1, 366 APPEND); 367 s += match[0].rm_so + 1; 368 slen -= match[0].rm_so + 1; 369 lastempty = 1; 370 } 371 } while (slen > 0 && regexec_e(re, s, REG_NOTBOL, 0, slen)); 372 /* Copy trailing retained string. */ 373 if (slen > 0) 374 cspace(&SS, s, slen, APPEND); 375 break; 376 default: /* Nth occurrence */ 377 while (--n) { 378 s += match[0].rm_eo; 379 slen -= match[0].rm_eo; 380 if (!regexec_e(re, s, REG_NOTBOL, 0, slen)) 381 return (0); 382 } 383 /* FALLTHROUGH */ 384 case 1: /* 1st occurrence */ 385 /* Locate start of replaced string. */ 386 re_off = match[0].rm_so + (s - ps); 387 /* Copy leading retained string. */ 388 cspace(&SS, ps, re_off, APPEND); 389 /* Add in regular expression. */ 390 regsub(&SS, s, cp->u.s->new); 391 /* Copy trailing retained string. */ 392 s += match[0].rm_eo; 393 slen -= match[0].rm_eo; 394 cspace(&SS, s, slen, APPEND); 395 break; 396 } 397 398 /* 399 * Swap the substitute space and the pattern space, and make sure 400 * that any leftover pointers into stdio memory get lost. 401 */ 402 tspace = PS; 403 PS = SS; 404 SS = tspace; 405 SS.space = SS.back; 406 407 /* Handle the 'p' flag. */ 408 if (cp->u.s->p) 409 OUT(ps) 410 411 /* Handle the 'w' flag. */ 412 if (cp->u.s->wfile && !pd) { 413 if (cp->u.s->wfd == -1 && (cp->u.s->wfd = open(cp->u.s->wfile, 414 O_WRONLY|O_APPEND|O_CREAT|O_TRUNC, DEFFILEMODE)) == -1) 415 err(FATAL, "%s: %s\n", cp->u.s->wfile, strerror(errno)); 416 if (write(cp->u.s->wfd, ps, psl) != psl) 417 err(FATAL, "%s: %s\n", cp->u.s->wfile, strerror(errno)); 418 } 419 return (1); 420 } 421 422 /* 423 * Flush append requests. Always called before reading a line, 424 * therefore it also resets the substitution done (sdone) flag. 425 */ 426 static void 427 flush_appends() 428 { 429 FILE *f; 430 int count, i; 431 char buf[8 * 1024]; 432 433 for (i = 0; i < appendx; i++) 434 switch (appends[i].type) { 435 case AP_STRING: 436 fwrite(appends[i].s, sizeof(char), appends[i].len, 437 stdout); 438 break; 439 case AP_FILE: 440 /* 441 * Read files probably shouldn't be cached. Since 442 * it's not an error to read a non-existent file, 443 * it's possible that another program is interacting 444 * with the sed script through the file system. It 445 * would be truly bizarre, but possible. It's probably 446 * not that big a performance win, anyhow. 447 */ 448 if ((f = fopen(appends[i].s, "r")) == NULL) 449 break; 450 while ((count = fread(buf, sizeof(char), sizeof(buf), f))) 451 (void)fwrite(buf, sizeof(char), count, stdout); 452 (void)fclose(f); 453 break; 454 } 455 if (ferror(stdout)) 456 err(FATAL, "stdout: %s", strerror(errno ? errno : EIO)); 457 appendx = sdone = 0; 458 } 459 460 static void 461 lputs(s) 462 register char *s; 463 { 464 register int count; 465 register char *escapes, *p; 466 struct winsize win; 467 static int termwidth = -1; 468 469 if (termwidth == -1) 470 if ((p = getenv("COLUMNS"))) 471 termwidth = atoi(p); 472 else if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &win) == 0 && 473 win.ws_col > 0) 474 termwidth = win.ws_col; 475 else 476 termwidth = 60; 477 478 for (count = 0; *s; ++s) { 479 if (count >= termwidth) { 480 (void)printf("\\\n"); 481 count = 0; 482 } 483 if (isascii(*s) && isprint(*s) && *s != '\\') { 484 (void)putchar(*s); 485 count++; 486 } else { 487 escapes = "\\\a\b\f\n\r\t\v"; 488 (void)putchar('\\'); 489 if ((p = strchr(escapes, *s))) { 490 (void)putchar("\\abfnrtv"[p - escapes]); 491 count += 2; 492 } else { 493 (void)printf("%03o", *(u_char *)s); 494 count += 4; 495 } 496 } 497 } 498 (void)putchar('$'); 499 (void)putchar('\n'); 500 if (ferror(stdout)) 501 err(FATAL, "stdout: %s", strerror(errno ? errno : EIO)); 502 } 503 504 static inline int 505 regexec_e(preg, string, eflags, nomatch, slen) 506 regex_t *preg; 507 const char *string; 508 int eflags, nomatch; 509 size_t slen; 510 { 511 int eval; 512 513 if (preg == NULL) { 514 if (defpreg == NULL) 515 err(FATAL, "first RE may not be empty"); 516 } else 517 defpreg = preg; 518 519 /* Set anchors, discounting trailing newline (if any). */ 520 if (slen > 0 && string[slen - 1] == '\n') 521 slen--; 522 match[0].rm_so = 0; 523 match[0].rm_eo = slen; 524 525 eval = regexec(defpreg, string, 526 nomatch ? 0 : maxnsub + 1, match, eflags | REG_STARTEND); 527 switch(eval) { 528 case 0: 529 return (1); 530 case REG_NOMATCH: 531 return (0); 532 } 533 err(FATAL, "RE error: %s", strregerror(eval, defpreg)); 534 /* NOTREACHED */ 535 } 536 537 /* 538 * regsub - perform substitutions after a regexp match 539 * Based on a routine by Henry Spencer 540 */ 541 static void 542 regsub(sp, string, src) 543 SPACE *sp; 544 char *string, *src; 545 { 546 register int len, no; 547 register char c, *dst; 548 549 #define NEEDSP(reqlen) \ 550 if (sp->len >= sp->blen - (reqlen) - 1) { \ 551 sp->blen += (reqlen) + 1024; \ 552 sp->space = sp->back = xrealloc(sp->back, sp->blen); \ 553 dst = sp->space + sp->len; \ 554 } 555 556 dst = sp->space + sp->len; 557 while ((c = *src++) != '\0') { 558 if (c == '&') 559 no = 0; 560 else if (c == '\\' && isdigit(*src)) 561 no = *src++ - '0'; 562 else 563 no = -1; 564 if (no < 0) { /* Ordinary character. */ 565 if (c == '\\' && (*src == '\\' || *src == '&')) 566 c = *src++; 567 NEEDSP(1); 568 *dst++ = c; 569 ++sp->len; 570 } else if (match[no].rm_so != -1 && match[no].rm_eo != -1) { 571 len = match[no].rm_eo - match[no].rm_so; 572 NEEDSP(len); 573 memmove(dst, string + match[no].rm_so, len); 574 dst += len; 575 sp->len += len; 576 } 577 } 578 NEEDSP(1); 579 *dst = '\0'; 580 } 581 582 /* 583 * aspace -- 584 * Append the source space to the destination space, allocating new 585 * space as necessary. 586 */ 587 void 588 cspace(sp, p, len, spflag) 589 SPACE *sp; 590 char *p; 591 size_t len; 592 enum e_spflag spflag; 593 { 594 size_t tlen; 595 596 /* Make sure SPACE has enough memory and ramp up quickly. */ 597 tlen = sp->len + len + 1; 598 if (tlen > sp->blen) { 599 sp->blen = tlen + 1024; 600 sp->space = sp->back = xrealloc(sp->back, sp->blen); 601 } 602 603 if (spflag == REPLACE) 604 sp->len = 0; 605 606 memmove(sp->space + sp->len, p, len); 607 608 sp->space[sp->len += len] = '\0'; 609 } 610 611 /* 612 * Close all cached opened files and report any errors 613 */ 614 void 615 cfclose(cp, end) 616 register struct s_command *cp, *end; 617 { 618 619 for (; cp != end; cp = cp->next) 620 switch(cp->code) { 621 case 's': 622 if (cp->u.s->wfd != -1 && close(cp->u.s->wfd)) 623 err(FATAL, 624 "%s: %s", cp->u.s->wfile, strerror(errno)); 625 cp->u.s->wfd = -1; 626 break; 627 case 'w': 628 if (cp->u.fd != -1 && close(cp->u.fd)) 629 err(FATAL, "%s: %s", cp->t, strerror(errno)); 630 cp->u.fd = -1; 631 break; 632 case '{': 633 cfclose(cp->u.c, cp->next); 634 break; 635 } 636 } 637