1 /* $OpenBSD: process.c,v 1.14 2008/10/07 21:51:37 millert 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. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #ifndef lint 37 /* from: static char sccsid[] = "@(#)process.c 8.1 (Berkeley) 6/6/93"; */ 38 static const char rcsid[] = "$OpenBSD: process.c,v 1.14 2008/10/07 21:51:37 millert Exp $"; 39 #endif /* not lint */ 40 41 #include <sys/types.h> 42 #include <sys/stat.h> 43 #include <sys/ioctl.h> 44 #include <sys/uio.h> 45 46 #include <ctype.h> 47 #include <errno.h> 48 #include <fcntl.h> 49 #include <limits.h> 50 #include <regex.h> 51 #include <stdio.h> 52 #include <stdlib.h> 53 #include <string.h> 54 #include <unistd.h> 55 56 #include "defs.h" 57 #include "extern.h" 58 59 static SPACE HS, PS, SS; 60 #define pd PS.deleted 61 #define ps PS.space 62 #define psl PS.len 63 #define hs HS.space 64 #define hsl HS.len 65 66 static inline int applies(struct s_command *); 67 static void flush_appends(void); 68 static void lputs(char *); 69 static inline int regexec_e(regex_t *, const char *, int, int, size_t); 70 static void regsub(SPACE *, char *, char *); 71 static int substitute(struct s_command *); 72 73 struct s_appends *appends; /* Array of pointers to strings to append. */ 74 static int appendx; /* Index into appends array. */ 75 int appendnum; /* Size of appends array. */ 76 77 static int lastaddr; /* Set by applies if last address of a range. */ 78 static int sdone; /* If any substitutes since last line input. */ 79 /* Iov structure for 'w' commands. */ 80 static regex_t *defpreg; 81 size_t maxnsub; 82 regmatch_t *match; 83 84 #define OUT(s) do { fwrite(s, sizeof(u_char), psl, stdout); } while (0) 85 86 void 87 process(void) 88 { 89 struct s_command *cp; 90 SPACE tspace; 91 size_t len, oldpsl; 92 char *p; 93 94 for (linenum = 0; mf_fgets(&PS, REPLACE);) { 95 pd = 0; 96 top: 97 cp = prog; 98 redirect: 99 while (cp != NULL) { 100 if (!applies(cp)) { 101 cp = cp->next; 102 continue; 103 } 104 switch (cp->code) { 105 case '{': 106 cp = cp->u.c; 107 goto redirect; 108 case 'a': 109 if (appendx >= appendnum) { 110 appends = xrealloc(appends, 111 sizeof(struct s_appends) * 112 (appendnum * 2)); 113 appendnum *= 2; 114 } 115 appends[appendx].type = AP_STRING; 116 appends[appendx].s = cp->t; 117 appends[appendx].len = strlen(cp->t); 118 appendx++; 119 break; 120 case 'b': 121 cp = cp->u.c; 122 goto redirect; 123 case 'c': 124 pd = 1; 125 psl = 0; 126 if (cp->a2 == NULL || lastaddr) 127 (void)printf("%s", cp->t); 128 break; 129 case 'd': 130 pd = 1; 131 goto new; 132 case 'D': 133 if (pd) 134 goto new; 135 if (psl == 0 || 136 (p = memchr(ps, '\n', psl - 1)) == NULL) { 137 pd = 1; 138 goto new; 139 } else { 140 psl -= (p + 1) - ps; 141 memmove(ps, p + 1, psl); 142 goto top; 143 } 144 case 'g': 145 cspace(&PS, hs, hsl, REPLACE); 146 break; 147 case 'G': 148 if (hs == NULL) 149 cspace(&HS, "\n", 1, REPLACE); 150 cspace(&PS, hs, hsl, 0); 151 break; 152 case 'h': 153 cspace(&HS, ps, psl, REPLACE); 154 break; 155 case 'H': 156 cspace(&HS, ps, psl, 0); 157 break; 158 case 'i': 159 (void)printf("%s", cp->t); 160 break; 161 case 'l': 162 lputs(ps); 163 break; 164 case 'n': 165 if (!nflag && !pd) 166 OUT(ps); 167 flush_appends(); 168 if (!mf_fgets(&PS, REPLACE)) 169 exit(0); 170 pd = 0; 171 break; 172 case 'N': 173 flush_appends(); 174 if (!mf_fgets(&PS, 0)) { 175 if (!nflag && !pd) 176 OUT(ps); 177 exit(0); 178 } 179 break; 180 case 'p': 181 if (pd) 182 break; 183 OUT(ps); 184 break; 185 case 'P': 186 if (pd) 187 break; 188 if (psl != 0 && 189 (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", 229 cp->t, strerror(errno)); 230 if (write(cp->u.fd, ps, psl) != psl) 231 err(FATAL, "%s: %s", 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 || psl == 0) 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(struct s_command *cp) 276 { 277 int r; 278 279 lastaddr = 0; 280 if (cp->a1 == NULL && cp->a2 == NULL) 281 r = 1; 282 else if (cp->a2) 283 if (cp->inrange) { 284 if (MATCH(cp->a2)) { 285 cp->inrange = 0; 286 lastaddr = 1; 287 } 288 r = 1; 289 } else if (MATCH(cp->a1)) { 290 /* 291 * If the second address is a number less than or 292 * equal to the line number first selected, only 293 * one line shall be selected. 294 * -- POSIX 1003.2 295 */ 296 if (cp->a2->type == AT_LINE && 297 linenum >= cp->a2->u.l) 298 lastaddr = 1; 299 else 300 cp->inrange = 1; 301 r = 1; 302 } else 303 r = 0; 304 else 305 r = MATCH(cp->a1); 306 return (cp->nonsel ? !r : r); 307 } 308 309 /* 310 * substitute -- 311 * Do substitutions in the pattern space. Currently, we build a 312 * copy of the new pattern space in the substitute space structure 313 * and then swap them. 314 */ 315 static int 316 substitute(struct s_command *cp) 317 { 318 SPACE tspace; 319 regex_t *re; 320 size_t re_off, slen; 321 int n, lastempty; 322 char *s; 323 324 s = ps; 325 re = cp->u.s->re; 326 if (re == NULL) { 327 if (defpreg != NULL && cp->u.s->maxbref > defpreg->re_nsub) { 328 linenum = cp->u.s->linenum; 329 err(COMPILE, "\\%d not defined in the RE", 330 cp->u.s->maxbref); 331 } 332 } 333 if (!regexec_e(re, s, 0, 0, psl)) 334 return (0); 335 336 SS.len = 0; /* Clean substitute space. */ 337 slen = psl; 338 n = cp->u.s->n; 339 lastempty = 1; 340 341 switch (n) { 342 case 0: /* Global */ 343 do { 344 if (lastempty || match[0].rm_so != match[0].rm_eo) { 345 /* Locate start of replaced string. */ 346 re_off = match[0].rm_so; 347 /* Copy leading retained string. */ 348 cspace(&SS, s, re_off, APPEND); 349 /* Add in regular expression. */ 350 regsub(&SS, s, cp->u.s->new); 351 } 352 353 /* Move past this match. */ 354 if (match[0].rm_so != match[0].rm_eo) { 355 s += match[0].rm_eo; 356 slen -= match[0].rm_eo; 357 lastempty = 0; 358 } else { 359 if (match[0].rm_so == 0) 360 cspace(&SS, s, match[0].rm_so + 1, 361 APPEND); 362 else 363 cspace(&SS, s + match[0].rm_so, 1, 364 APPEND); 365 s += match[0].rm_so + 1; 366 slen -= match[0].rm_so + 1; 367 lastempty = 1; 368 } 369 } while (slen > 0 && regexec_e(re, s, REG_NOTBOL, 0, slen)); 370 /* Copy trailing retained string. */ 371 if (slen > 0) 372 cspace(&SS, s, slen, APPEND); 373 break; 374 default: /* Nth occurrence */ 375 while (--n) { 376 s += match[0].rm_eo; 377 slen -= match[0].rm_eo; 378 if (!regexec_e(re, s, REG_NOTBOL, 0, slen)) 379 return (0); 380 } 381 /* FALLTHROUGH */ 382 case 1: /* 1st occurrence */ 383 /* Locate start of replaced string. */ 384 re_off = match[0].rm_so + (s - ps); 385 /* Copy leading retained string. */ 386 cspace(&SS, ps, re_off, APPEND); 387 /* Add in regular expression. */ 388 regsub(&SS, s, cp->u.s->new); 389 /* Copy trailing retained string. */ 390 s += match[0].rm_eo; 391 slen -= match[0].rm_eo; 392 cspace(&SS, s, slen, APPEND); 393 break; 394 } 395 396 /* 397 * Swap the substitute space and the pattern space, and make sure 398 * that any leftover pointers into stdio memory get lost. 399 */ 400 tspace = PS; 401 PS = SS; 402 SS = tspace; 403 SS.space = SS.back; 404 405 /* Handle the 'p' flag. */ 406 if (cp->u.s->p) 407 OUT(ps); 408 409 /* Handle the 'w' flag. */ 410 if (cp->u.s->wfile && !pd) { 411 if (cp->u.s->wfd == -1 && (cp->u.s->wfd = open(cp->u.s->wfile, 412 O_WRONLY|O_APPEND|O_CREAT|O_TRUNC, DEFFILEMODE)) == -1) 413 err(FATAL, "%s: %s", cp->u.s->wfile, strerror(errno)); 414 if (write(cp->u.s->wfd, ps, psl) != psl) 415 err(FATAL, "%s: %s", cp->u.s->wfile, strerror(errno)); 416 } 417 return (1); 418 } 419 420 /* 421 * Flush append requests. Always called before reading a line, 422 * therefore it also resets the substitution done (sdone) flag. 423 */ 424 static void 425 flush_appends(void) 426 { 427 FILE *f; 428 int count, i; 429 char buf[8 * 1024]; 430 431 for (i = 0; i < appendx; i++) 432 switch (appends[i].type) { 433 case AP_STRING: 434 fwrite(appends[i].s, sizeof(char), appends[i].len, 435 stdout); 436 break; 437 case AP_FILE: 438 /* 439 * Read files probably shouldn't be cached. Since 440 * it's not an error to read a non-existent file, 441 * it's possible that another program is interacting 442 * with the sed script through the file system. It 443 * would be truly bizarre, but possible. It's probably 444 * not that big a performance win, anyhow. 445 */ 446 if ((f = fopen(appends[i].s, "r")) == NULL) 447 break; 448 while ((count = fread(buf, sizeof(char), sizeof(buf), f))) 449 (void)fwrite(buf, sizeof(char), count, stdout); 450 (void)fclose(f); 451 break; 452 } 453 if (ferror(stdout)) 454 err(FATAL, "stdout: %s", strerror(errno ? errno : EIO)); 455 appendx = sdone = 0; 456 } 457 458 static void 459 lputs(char *s) 460 { 461 int count; 462 char *escapes, *p; 463 struct winsize win; 464 static int termwidth = -1; 465 466 if (termwidth == -1) { 467 if ((p = getenv("COLUMNS"))) 468 termwidth = atoi(p); 469 else if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &win) == 0 && 470 win.ws_col > 0) 471 termwidth = win.ws_col; 472 else 473 termwidth = 60; 474 } 475 476 for (count = 0; *s; ++s) { 477 if (count >= termwidth) { 478 (void)printf("\\\n"); 479 count = 0; 480 } 481 if (isascii(*s) && isprint(*s) && *s != '\\') { 482 (void)putchar(*s); 483 count++; 484 } else if (*s != '\n') { 485 escapes = "\\\a\b\f\r\t\v"; 486 (void)putchar('\\'); 487 if ((p = strchr(escapes, *s))) { 488 (void)putchar("\\abfrtv"[p - escapes]); 489 count += 2; 490 } else { 491 (void)printf("%03o", *(u_char *)s); 492 count += 4; 493 } 494 } 495 } 496 (void)putchar('$'); 497 (void)putchar('\n'); 498 if (ferror(stdout)) 499 err(FATAL, "stdout: %s", strerror(errno ? errno : EIO)); 500 } 501 502 static inline int 503 regexec_e(regex_t *preg, const char *string, int eflags, 504 int nomatch, size_t slen) 505 { 506 int eval; 507 508 if (preg == NULL) { 509 if (defpreg == NULL) 510 err(FATAL, "first RE may not be empty"); 511 } else 512 defpreg = preg; 513 514 /* Set anchors, discounting trailing newline (if any). */ 515 if (slen > 0 && string[slen - 1] == '\n') 516 slen--; 517 match[0].rm_so = 0; 518 match[0].rm_eo = slen; 519 520 eval = regexec(defpreg, string, 521 nomatch ? 0 : maxnsub + 1, match, eflags | REG_STARTEND); 522 switch (eval) { 523 case 0: 524 return (1); 525 case REG_NOMATCH: 526 return (0); 527 } 528 err(FATAL, "RE error: %s", strregerror(eval, defpreg)); 529 /* NOTREACHED */ 530 } 531 532 /* 533 * regsub - perform substitutions after a regexp match 534 * Based on a routine by Henry Spencer 535 */ 536 static void 537 regsub(SPACE *sp, char *string, char *src) 538 { 539 int len, no; 540 char c, *dst; 541 542 #define NEEDSP(reqlen) \ 543 if (sp->len + (reqlen) + 1 >= sp->blen) { \ 544 size_t newlen = sp->blen + (reqlen) + 1024; \ 545 sp->space = sp->back = xrealloc(sp->back, newlen); \ 546 sp->blen = newlen; \ 547 dst = sp->space + sp->len; \ 548 } 549 550 dst = sp->space + sp->len; 551 while ((c = *src++) != '\0') { 552 if (c == '&') 553 no = 0; 554 else if (c == '\\' && isdigit(*src)) 555 no = *src++ - '0'; 556 else 557 no = -1; 558 if (no < 0) { /* Ordinary character. */ 559 if (c == '\\' && (*src == '\\' || *src == '&')) 560 c = *src++; 561 NEEDSP(1); 562 *dst++ = c; 563 ++sp->len; 564 } else if (match[no].rm_so != -1 && match[no].rm_eo != -1) { 565 len = match[no].rm_eo - match[no].rm_so; 566 NEEDSP(len); 567 memmove(dst, string + match[no].rm_so, len); 568 dst += len; 569 sp->len += len; 570 } 571 } 572 NEEDSP(1); 573 *dst = '\0'; 574 } 575 576 /* 577 * aspace -- 578 * Append the source space to the destination space, allocating new 579 * space as necessary. 580 */ 581 void 582 cspace(SPACE *sp, char *p, size_t len, enum e_spflag spflag) 583 { 584 size_t tlen; 585 586 /* Make sure SPACE has enough memory and ramp up quickly. */ 587 tlen = sp->len + len + 1; 588 if (tlen > sp->blen) { 589 size_t newlen = tlen + 1024; 590 sp->space = sp->back = xrealloc(sp->back, newlen); 591 sp->blen = newlen; 592 } 593 594 if (spflag == REPLACE) 595 sp->len = 0; 596 597 memmove(sp->space + sp->len, p, len); 598 599 sp->space[sp->len += len] = '\0'; 600 } 601 602 /* 603 * Close all cached opened files and report any errors 604 */ 605 void 606 cfclose(struct s_command *cp, struct s_command *end) 607 { 608 609 for (; cp != end; cp = cp->next) 610 switch (cp->code) { 611 case 's': 612 if (cp->u.s->wfd != -1 && close(cp->u.s->wfd)) 613 err(FATAL, 614 "%s: %s", cp->u.s->wfile, strerror(errno)); 615 cp->u.s->wfd = -1; 616 break; 617 case 'w': 618 if (cp->u.fd != -1 && close(cp->u.fd)) 619 err(FATAL, "%s: %s", cp->t, strerror(errno)); 620 cp->u.fd = -1; 621 break; 622 case '{': 623 cfclose(cp->u.c, cp->next); 624 break; 625 } 626 } 627