usr.bin/sed/process.c

   1 /*      $NetBSD: process.c,v 1.52 2015/03/12 12:40:41 christos Exp $    */
   2
   3 /*-
   4  * Copyright (c) 1992 Diomidis Spinellis.
   5  * Copyright (c) 1992, 1993, 1994
   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 #if HAVE_NBTOOL_CONFIG_H
  37 #include "nbtool_config.h"
  38 #endif
  39
  40 #include <sys/cdefs.h>
  41 __RCSID("$NetBSD: process.c,v 1.52 2015/03/12 12:40:41 christos Exp $");
  42 #ifdef __FBSDID
  43 __FBSDID("$FreeBSD: head/usr.bin/sed/process.c 192732 2009-05-25 06:45:33Z brian $");
  44 #endif
  45
  46 #if 0
  47 static const char sccsid[] = "@(#)process.c     8.6 (Berkeley) 4/20/94";
  48 #endif
  49
  50 #include <sys/types.h>
  51 #include <sys/stat.h>
  52 #include <sys/ioctl.h>
  53 #include <sys/uio.h>
  54
  55 #include <ctype.h>
  56 #include <err.h>
  57 #include <errno.h>
  58 #include <fcntl.h>
  59 #include <limits.h>
  60 #include <regex.h>
  61 #include <stdio.h>
  62 #include <stdlib.h>
  63 #include <string.h>
  64 #include <unistd.h>
  65 #include <wchar.h>
  66 #include <wctype.h>
  67
  68 #include "defs.h"
  69 #include "extern.h"
  70
  71 static SPACE HS, PS, SS, YS;
  72 #define pd              PS.deleted
  73 #define ps              PS.space
  74 #define psl             PS.len
  75 #define hs              HS.space
  76 #define hsl             HS.len
  77
  78 static __inline int      applies(struct s_command *);
  79 static void              do_tr(struct s_tr *);
  80 static void              flush_appends(void);
  81 static void              lputs(char *, size_t);
  82 static __inline int      regexec_e(regex_t *, const char *, int, int, size_t);
  83 static void              regsub(SPACE *, char *, char *);
  84 static int               substitute(struct s_command *);
  85
  86 struct s_appends *appends;      /* Array of pointers to strings to append. */
  87 static size_t appendx;          /* Index into appends array. */
  88 size_t appendnum;                       /* Size of appends array. */
  89
  90 static int lastaddr;            /* Set by applies if last address of a range. */
  91 static int sdone;               /* If any substitutes since last line input. */
  92                                 /* Iov structure for 'w' commands. */
  93 static regex_t *defpreg;
  94 size_t maxnsub;
  95 regmatch_t *match;
  96
  97 #define OUT() do {fwrite(ps, 1, psl, outfile); fputc('\n', outfile);} while (0)
  98
  99 void
 100 process(void)
 101 {
 102         struct s_command *cp;
 103         SPACE tspace;
 104         size_t oldpsl = 0;
 105         char *p;
 106
 107         p = NULL;
 108
 109         for (linenum = 0; mf_fgets(&PS, REPLACE);) {
 110                 pd = 0;
 111 top:
 112                 cp = prog;
 113 redirect:
 114                 while (cp != NULL) {
 115                         if (!applies(cp)) {
 116                                 cp = cp->next;
 117                                 continue;
 118                         }
 119                         switch (cp->code) {
 120                         case '{':
 121                                 cp = cp->u.c;
 122                                 goto redirect;
 123                         case 'a':
 124                                 if (appendx >= appendnum)
 125                                         appends = xrealloc(appends,
 126                                             sizeof(struct s_appends) *
 127                                             (appendnum *= 2));
 128                                 appends[appendx].type = AP_STRING;
 129                                 appends[appendx].s = cp->t;
 130                                 appends[appendx].len = strlen(cp->t);
 131                                 appendx++;
 132                                 break;
 133                         case 'b':
 134                                 cp = cp->u.c;
 135                                 goto redirect;
 136                         case 'c':
 137                                 pd = 1;
 138                                 psl = 0;
 139                                 if (cp->a2 == NULL || lastaddr || lastline())
 140                                         (void)fprintf(outfile, "%s", cp->t);
 141                                 goto new;
 142                         case 'd':
 143                                 pd = 1;
 144                                 goto new;
 145                         case 'D':
 146                                 if (pd)
 147                                         goto new;
 148                                 if (psl == 0 ||
 149                                     (p = memchr(ps, '\n', psl - 1)) == NULL) {
 150                                         pd = 1;
 151                                         goto new;
 152                                 } else {
 153                                         psl -= (size_t)((p + 1) - ps);
 154                                         memmove(ps, p + 1, psl);
 155                                         goto top;
 156                                 }
 157                         case 'g':
 158                                 cspace(&PS, hs, hsl, REPLACE);
 159                                 break;
 160                         case 'G':
 161                                 cspace(&PS, "\n", 1, APPEND);
 162                                 cspace(&PS, hs, hsl, APPEND);
 163                                 break;
 164                         case 'h':
 165                                 cspace(&HS, ps, psl, REPLACE);
 166                                 break;
 167                         case 'H':
 168                                 cspace(&HS, "\n", 1, APPEND);
 169                                 cspace(&HS, ps, psl, APPEND);
 170                                 break;
 171                         case 'i':
 172                                 (void)fprintf(outfile, "%s", cp->t);
 173                                 break;
 174                         case 'l':
 175                                 lputs(ps, psl);
 176                                 break;
 177                         case 'n':
 178                                 if (!nflag && !pd)
 179                                         OUT();
 180                                 flush_appends();
 181                                 if (!mf_fgets(&PS, REPLACE))
 182                                         exit(0);
 183                                 pd = 0;
 184                                 break;
 185                         case 'N':
 186                                 flush_appends();
 187                                 cspace(&PS, "\n", 1, APPEND);
 188                                 if (!mf_fgets(&PS, APPEND))
 189                                         exit(0);
 190                                 break;
 191                         case 'p':
 192                                 if (pd)
 193                                         break;
 194                                 OUT();
 195                                 break;
 196                         case 'P':
 197                                 if (pd)
 198                                         break;
 199                                 if ((p = memchr(ps, '\n', psl - 1)) != NULL) {
 200                                         oldpsl = psl;
 201                                         psl = (size_t)(p - ps);
 202                                 }
 203                                 OUT();
 204                                 if (p != NULL)
 205                                         psl = oldpsl;
 206                                 break;
 207                         case 'q':
 208                                 if (!nflag && !pd)
 209                                         OUT();
 210                                 flush_appends();
 211                                 exit(0);
 212                         case 'r':
 213                                 if (appendx >= appendnum)
 214                                         appends = xrealloc(appends,
 215                                             sizeof(struct s_appends) *
 216                                             (appendnum *= 2));
 217                                 appends[appendx].type = AP_FILE;
 218                                 appends[appendx].s = cp->t;
 219                                 appends[appendx].len = strlen(cp->t);
 220                                 appendx++;
 221                                 break;
 222                         case 's':
 223                                 sdone |= substitute(cp);
 224                                 break;
 225                         case 't':
 226                                 if (sdone) {
 227                                         sdone = 0;
 228                                         cp = cp->u.c;
 229                                         goto redirect;
 230                                 }
 231                                 break;
 232                         case 'w':
 233                                 if (pd)
 234                                         break;
 235                                 if (cp->u.fd == -1 && (cp->u.fd = open(cp->t,
 236                                     O_WRONLY|O_APPEND|O_CREAT|O_TRUNC,
 237                                     DEFFILEMODE)) == -1)
 238                                         err(1, "%s", cp->t);
 239                                 if (write(cp->u.fd, ps, psl) != (ssize_t)psl ||
 240                                     write(cp->u.fd, "\n", 1) != 1)
 241                                         err(1, "%s", cp->t);
 242                                 break;
 243                         case 'x':
 244                                 /*
 245                                  * If the hold space is null, make it empty
 246                                  * but not null.  Otherwise the pattern space
 247                                  * will become null after the swap, which is
 248                                  * an abnormal condition.
 249                                  */
 250                                 if (hs == NULL)
 251                                         cspace(&HS, "", 0, REPLACE);
 252                                 tspace = PS;
 253                                 PS = HS;
 254                                 HS = tspace;
 255                                 break;
 256                         case 'y':
 257                                 if (pd || psl == 0)
 258                                         break;
 259                                 do_tr(cp->u.y);
 260                                 break;
 261                         case ':':
 262                         case '}':
 263                                 break;
 264                         case '=':
 265                                 (void)fprintf(outfile, "%lu\n", linenum);
 266                         }
 267                         cp = cp->next;
 268                 } /* for all cp */
 269
 270 new:            if (!nflag && !pd)
 271                         OUT();
 272                 flush_appends();
 273         } /* for all lines */
 274 }
 275
 276 /*
 277  * TRUE if the address passed matches the current program state
 278  * (lastline, linenumber, ps).
 279  */
 280 #define MATCH(a)                                                        \
 281         ((a)->type == AT_RE ? regexec_e((a)->u.r, ps, 0, 1, psl) :      \
 282             (a)->type == AT_LINE ? linenum == (a)->u.l : lastline())
 283
 284 /*
 285  * Return TRUE if the command applies to the current line.  Sets the start
 286  * line for process ranges.  Interprets the non-select (``!'') flag.
 287  */
 288 static __inline int
 289 applies(struct s_command *cp)
 290 {
 291         int r;
 292
 293         lastaddr = 0;
 294         if (cp->a1 == NULL && cp->a2 == NULL)
 295                 r = 1;
 296         else if (cp->a2)
 297                 if (cp->startline > 0) {
 298                         switch (cp->a2->type) {
 299                         case AT_RELLINE:
 300                                 if (linenum - cp->startline <= cp->a2->u.l)
 301                                         r = 1;
 302                                 else {
 303                                         cp->startline = 0;
 304                                         r = 0;
 305                                 }
 306                                 break;
 307                         default:
 308                                 if (MATCH(cp->a2)) {
 309                                         cp->startline = 0;
 310                                         lastaddr = 1;
 311                                         r = 1;
 312                                 } else if (cp->a2->type == AT_LINE &&
 313                                     linenum > cp->a2->u.l) {
 314                                         /*
 315                                          * We missed the 2nd address due to a
 316                                          * branch, so just close the range and
 317                                          * return false.
 318                                          */
 319                                         cp->startline = 0;
 320                                         r = 0;
 321                                 } else
 322                                         r = 1;
 323                         }
 324                 } else if (cp->a1 && MATCH(cp->a1)) {
 325                         /*
 326                          * If the second address is a number less than or
 327                          * equal to the line number first selected, only
 328                          * one line shall be selected.
 329                          *      -- POSIX 1003.2
 330                          * Likewise if the relative second line address is zero.
 331                          */
 332                         if ((cp->a2->type == AT_LINE &&
 333                             linenum >= cp->a2->u.l) ||
 334                             (cp->a2->type == AT_RELLINE && cp->a2->u.l == 0))
 335                                 lastaddr = 1;
 336                         else {
 337                                 cp->startline = linenum;
 338                         }
 339                         r = 1;
 340                 } else
 341                         r = 0;
 342         else
 343                 r = MATCH(cp->a1);
 344         return (cp->nonsel ? ! r : r);
 345 }
 346
 347 /*
 348  * Reset the sed processor to its initial state.
 349  */
 350 void
 351 resetstate(void)
 352 {
 353         struct s_command *cp;
 354
 355         /*
 356          * Reset all in-range markers.
 357          */
 358         for (cp = prog; cp; cp = cp->code == '{' ? cp->u.c : cp->next)
 359                 if (cp->a2)
 360                         cp->startline = 0;
 361
 362         /*
 363          * Clear out the hold space.
 364          */
 365         cspace(&HS, "", 0, REPLACE);
 366 }
 367
 368 /*
 369  * substitute --
 370  *      Do substitutions in the pattern space.  Currently, we build a
 371  *      copy of the new pattern space in the substitute space structure
 372  *      and then swap them.
 373  */
 374 static int
 375 substitute(struct s_command *cp)
 376 {
 377         SPACE tspace;
 378         regex_t *re;
 379         regoff_t re_off, slen;
 380         int lastempty, n;
 381         char *s;
 382
 383         s = ps;
 384         re = cp->u.s->re;
 385         if (re == NULL) {
 386                 if (defpreg != NULL && cp->u.s->maxbref > defpreg->re_nsub) {
 387                         linenum = cp->u.s->linenum;
 388                         errx(1, "%lu: %s: \\%u not defined in the RE",
 389                                         linenum, fname, cp->u.s->maxbref);
 390                 }
 391         }
 392         if (!regexec_e(re, s, 0, 0, psl))
 393                 return (0);
 394
 395         SS.len = 0;                             /* Clean substitute space. */
 396         slen = (regoff_t)psl;
 397         n = cp->u.s->n;
 398         lastempty = 1;
 399
 400         switch (n) {
 401         case 0:                                 /* Global */
 402                 do {
 403                         if (lastempty || match[0].rm_so != match[0].rm_eo) {
 404                                 /* Locate start of replaced string. */
 405                                 re_off = match[0].rm_so;
 406                                 /* Copy leading retained string. */
 407                                 cspace(&SS, s, (size_t)re_off, APPEND);
 408                                 /* Add in regular expression. */
 409                                 regsub(&SS, s, cp->u.s->new);
 410                         }
 411
 412                         /* Move past this match. */
 413                         if (match[0].rm_so != match[0].rm_eo) {
 414                                 s += match[0].rm_eo;
 415                                 slen -= match[0].rm_eo;
 416                                 lastempty = 0;
 417                         } else {
 418                                 if (match[0].rm_so < slen)
 419                                         cspace(&SS, s + match[0].rm_so, 1,
 420                                             APPEND);
 421                                 s += match[0].rm_so + 1;
 422                                 slen -= match[0].rm_so + 1;
 423                                 lastempty = 1;
 424                         }
 425                 } while (slen >= 0 && regexec_e(re, s, REG_NOTBOL, 0, (size_t)slen));
 426                 /* Copy trailing retained string. */
 427                 if (slen > 0)
 428                         cspace(&SS, s, (size_t)slen, APPEND);
 429                 break;
 430         default:                                /* Nth occurrence */
 431                 while (--n) {
 432                         if (match[0].rm_eo == match[0].rm_so)
 433                                 match[0].rm_eo = match[0].rm_so + 1;
 434                         s += match[0].rm_eo;
 435                         slen -= match[0].rm_eo;
 436                         if (slen < 0)
 437                                 return (0);
 438                         if (!regexec_e(re, s, REG_NOTBOL, 0, (size_t)slen))
 439                                 return (0);
 440                 }
 441                 /* FALLTHROUGH */
 442         case 1:                                 /* 1st occurrence */
 443                 /* Locate start of replaced string. */
 444                 re_off = match[0].rm_so + (s - ps);
 445                 /* Copy leading retained string. */
 446                 cspace(&SS, ps, (size_t)re_off, APPEND);
 447                 /* Add in regular expression. */
 448                 regsub(&SS, s, cp->u.s->new);
 449                 /* Copy trailing retained string. */
 450                 s += match[0].rm_eo;
 451                 slen -= match[0].rm_eo;
 452                 cspace(&SS, s, (size_t)slen, APPEND);
 453                 break;
 454         }
 455
 456         /*
 457          * Swap the substitute space and the pattern space, and make sure
 458          * that any leftover pointers into stdio memory get lost.
 459          */
 460         tspace = PS;
 461         PS = SS;
 462         SS = tspace;
 463         SS.space = SS.back;
 464
 465         /* Handle the 'p' flag. */
 466         if (cp->u.s->p)
 467                 OUT();
 468
 469         /* Handle the 'w' flag. */
 470         if (cp->u.s->wfile && !pd) {
 471                 if (cp->u.s->wfd == -1 && (cp->u.s->wfd = open(cp->u.s->wfile,
 472                     O_WRONLY|O_APPEND|O_CREAT|O_TRUNC, DEFFILEMODE)) == -1)
 473                         err(1, "%s", cp->u.s->wfile);
 474                 if (write(cp->u.s->wfd, ps, psl) != (ssize_t)psl ||
 475                     write(cp->u.s->wfd, "\n", 1) != 1)
 476                         err(1, "%s", cp->u.s->wfile);
 477         }
 478         return (1);
 479 }
 480
 481 /*
 482  * do_tr --
 483  *      Perform translation ('y' command) in the pattern space.
 484  */
 485 static void
 486 do_tr(struct s_tr *y)
 487 {
 488         SPACE tmp;
 489         char c, *p;
 490         size_t clen, left;
 491         size_t i;
 492
 493         if (MB_CUR_MAX == 1) {
 494                 /*
 495                  * Single-byte encoding: perform in-place translation
 496                  * of the pattern space.
 497                  */
 498                 for (p = ps; p < &ps[psl]; p++)
 499                         *p = (char)y->bytetab[(u_char)*p];
 500         } else {
 501                 /*
 502                  * Multi-byte encoding: perform translation into the
 503                  * translation space, then swap the translation and
 504                  * pattern spaces.
 505                  */
 506                 /* Clean translation space. */
 507                 YS.len = 0;
 508                 for (p = ps, left = psl; left > 0; p += clen, left -= clen) {
 509                         if ((c = (char)y->bytetab[(u_char)*p]) != '\0') {
 510                                 cspace(&YS, &c, 1, APPEND);
 511                                 clen = 1;
 512                                 continue;
 513                         }
 514                         for (i = 0; i < y->nmultis; i++)
 515                                 if (left >= y->multis[i].fromlen &&
 516                                     memcmp(p, y->multis[i].from,
 517                                     y->multis[i].fromlen) == 0)
 518                                         break;
 519                         if (i < y->nmultis) {
 520                                 cspace(&YS, y->multis[i].to,
 521                                     y->multis[i].tolen, APPEND);
 522                                 clen = y->multis[i].fromlen;
 523                         } else {
 524                                 cspace(&YS, p, 1, APPEND);
 525                                 clen = 1;
 526                         }
 527                 }
 528                 /* Swap the translation space and the pattern space. */
 529                 tmp = PS;
 530                 PS = YS;
 531                 YS = tmp;
 532                 YS.space = YS.back;
 533         }
 534 }
 535
 536 /*
 537  * Flush append requests.  Always called before reading a line,
 538  * therefore it also resets the substitution done (sdone) flag.
 539  */
 540 static void
 541 flush_appends(void)
 542 {
 543         FILE *f;
 544         size_t count, i;
 545         char buf[8 * 1024];
 546
 547         for (i = 0; i < appendx; i++)
 548                 switch (appends[i].type) {
 549                 case AP_STRING:
 550                         fwrite(appends[i].s, sizeof(char), appends[i].len,
 551                             outfile);
 552                         break;
 553                 case AP_FILE:
 554                         /*
 555                          * Read files probably shouldn't be cached.  Since
 556                          * it's not an error to read a non-existent file,
 557                          * it's possible that another program is interacting
 558                          * with the sed script through the filesystem.  It
 559                          * would be truly bizarre, but possible.  It's probably
 560                          * not that big a performance win, anyhow.
 561                          */
 562                         if ((f = fopen(appends[i].s, "r")) == NULL)
 563                                 break;
 564                         while ((count = fread(buf, sizeof(char), sizeof(buf), f)))
 565                                 (void)fwrite(buf, sizeof(char), count, outfile);
 566                         (void)fclose(f);
 567                         break;
 568                 }
 569         if (ferror(outfile))
 570                 errx(1, "%s: %s", outfname, strerror(errno ? errno : EIO));
 571         appendx = 0;
 572         sdone = 0;
 573 }
 574
 575 static void
 576 lputs(char *s, size_t len)
 577 {
 578         static const char escapes[] = "\\\a\b\f\r\t\v";
 579         int c;
 580         size_t col, width;
 581         const char *p;
 582 #ifdef TIOCGWINSZ
 583         struct winsize win;
 584 #endif
 585         static size_t termwidth = (size_t)-1;
 586         size_t clen, i;
 587         wchar_t wc;
 588         mbstate_t mbs;
 589
 590         if (outfile != stdout)
 591                 termwidth = 60;
 592         if (termwidth == (size_t)-1) {
 593                 if ((p = getenv("COLUMNS")) && *p != '\0')
 594                         termwidth = (size_t)atoi(p);
 595 #ifdef TIOCGWINSZ
 596                 else if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &win) == 0 &&
 597                     win.ws_col > 0)
 598                         termwidth = win.ws_col;
 599 #endif
 600                 else
 601                         termwidth = 60;
 602         }
 603         if (termwidth == 0)
 604                 termwidth = 1;
 605
 606         memset(&mbs, 0, sizeof(mbs));
 607         col = 0;
 608         while (len != 0) {
 609                 clen = mbrtowc(&wc, s, len, &mbs);
 610                 if (clen == 0)
 611                         clen = 1;
 612                 if (clen == (size_t)-1 || clen == (size_t)-2) {
 613                         wc = (unsigned char)*s;
 614                         clen = 1;
 615                         memset(&mbs, 0, sizeof(mbs));
 616                 }
 617                 if (wc == '\n') {
 618                         if (col + 1 >= termwidth)
 619                                 fprintf(outfile, "\\\n");
 620                         fputc('$', outfile);
 621                         fputc('\n', outfile);
 622                         col = 0;
 623                 } else if (iswprint(wc)) {
 624                         width = (size_t)wcwidth(wc);
 625                         if (col + width >= termwidth) {
 626                                 fprintf(outfile, "\\\n");
 627                                 col = 0;
 628                         }
 629                         fwrite(s, 1, clen, outfile);
 630                         col += width;
 631                 } else if (wc != L'\0' && (c = wctob(wc)) != EOF &&
 632                     (p = strchr(escapes, c)) != NULL) {
 633                         if (col + 2 >= termwidth) {
 634                                 fprintf(outfile, "\\\n");
 635                                 col = 0;
 636                         }
 637                         fprintf(outfile, "\\%c", "\\abfrtv"[p - escapes]);
 638                         col += 2;
 639                 } else {
 640                         if (col + 4 * clen >= termwidth) {
 641                                 fprintf(outfile, "\\\n");
 642                                 col = 0;
 643                         }
 644                         for (i = 0; i < clen; i++)
 645                                 fprintf(outfile, "\\%03o",
 646                                     (int)(unsigned char)s[i]);
 647                         col += 4 * clen;
 648                 }
 649                 s += clen;
 650                 len -= clen;
 651         }
 652         if (col + 1 >= termwidth)
 653                 fprintf(outfile, "\\\n");
 654         (void)fputc('$', outfile);
 655         (void)fputc('\n', outfile);
 656         if (ferror(outfile))
 657                 errx(1, "%s: %s", outfname, strerror(errno ? errno : EIO));
 658 }
 659
 660 static __inline int
 661 regexec_e(regex_t *preg, const char *string, int eflags, int nomatch,
 662         size_t slen)
 663 {
 664         int eval;
 665 #ifndef REG_STARTEND
 666         char *buf;
 667 #endif
 668
 669         if (preg == NULL) {
 670                 if (defpreg == NULL)
 671                         errx(1, "first RE may not be empty");
 672         } else
 673                 defpreg = preg;
 674
 675         /* Set anchors */
 676 #ifndef REG_STARTEND
 677         buf = xmalloc(slen + 1);
 678         (void)memcpy(buf, string, slen);
 679         buf[slen] = '\0';
 680         eval = regexec(defpreg, buf,
 681             nomatch ? 0 : maxnsub + 1, match, eflags);
 682         free(buf);
 683 #else
 684         match[0].rm_so = 0;
 685         match[0].rm_eo = (regoff_t)slen;
 686         eval = regexec(defpreg, string,
 687             nomatch ? 0 : maxnsub + 1, match, eflags | REG_STARTEND);
 688 #endif
 689         switch(eval) {
 690         case 0:
 691                 return (1);
 692         case REG_NOMATCH:
 693                 return (0);
 694         }
 695         errx(1, "RE error: %s", strregerror(eval, defpreg));
 696         /* NOTREACHED */
 697 }
 698
 699 /*
 700  * regsub - perform substitutions after a regexp match
 701  * Based on a routine by Henry Spencer
 702  */
 703 static void
 704 regsub(SPACE *sp, char *string, char *src)
 705 {
 706         size_t len;
 707         int no;
 708         char c, *dst;
 709
 710 #define NEEDSP(reqlen)                                                  \
 711         /* XXX What is the +1 for? */                                   \
 712         if (sp->len + (reqlen) + 1 >= sp->blen) {                       \
 713                 sp->blen += (reqlen) + 1024;                            \
 714                 sp->space = sp->back = xrealloc(sp->back, sp->blen);    \
 715                 dst = sp->space + sp->len;                              \
 716         }
 717
 718         dst = sp->space + sp->len;
 719         while ((c = *src++) != '\0') {
 720                 if (c == '&')
 721                         no = 0;
 722                 else if (c == '\\' && isdigit((unsigned char)*src))
 723                         no = *src++ - '0';
 724                 else
 725                         no = -1;
 726                 if (no < 0) {           /* Ordinary character. */
 727                         if (c == '\\' && (*src == '\\' || *src == '&'))
 728                                 c = *src++;
 729                         NEEDSP(1);
 730                         *dst++ = c;
 731                         ++sp->len;
 732                 } else if (match[no].rm_so != -1 && match[no].rm_eo != -1) {
 733                         len = (size_t)(match[no].rm_eo - match[no].rm_so);
 734                         NEEDSP(len);
 735                         memmove(dst, string + match[no].rm_so, len);
 736                         dst += len;
 737                         sp->len += len;
 738                 }
 739         }
 740         NEEDSP(1);
 741         *dst = '\0';
 742 }
 743
 744 /*
 745  * cspace --
 746  *      Concatenate space: append the source space to the destination space,
 747  *      allocating new space as necessary.
 748  */
 749 void
 750 cspace(SPACE *sp, const char *p, size_t len, enum e_spflag spflag)
 751 {
 752         size_t tlen;
 753
 754         /* Make sure SPACE has enough memory and ramp up quickly. */
 755         tlen = sp->len + len + 1;
 756         if (tlen > sp->blen) {
 757                 sp->blen = tlen + 1024;
 758                 sp->space = sp->back = xrealloc(sp->back, sp->blen);
 759         }
 760
 761         if (spflag == REPLACE)
 762                 sp->len = 0;
 763
 764         memmove(sp->space + sp->len, p, len);
 765
 766         sp->space[sp->len += len] = '\0';
 767 }
 768
 769 /*
 770  * Close all cached opened files and report any errors
 771  */
 772 void
 773 cfclose(struct s_command *cp, struct s_command *end)
 774 {
 775
 776         for (; cp != end; cp = cp->next)
 777                 switch(cp->code) {
 778                 case 's':
 779                         if (cp->u.s->wfd != -1 && close(cp->u.s->wfd))
 780                                 err(1, "%s", cp->u.s->wfile);
 781                         cp->u.s->wfd = -1;
 782                         break;
 783                 case 'w':
 784                         if (cp->u.fd != -1 && close(cp->u.fd))
 785                                 err(1, "%s", cp->t);
 786                         cp->u.fd = -1;
 787                         break;
 788                 case '{':
 789                         cfclose(cp->u.c, cp->next);
 790                         break;
 791                 }
 792 }