usr.bin/sed/process.c

   1 /*-
   2  * Copyright (c) 1992 Diomidis Spinellis.
   3  * Copyright (c) 1992, 1993, 1994
   4  *      The Regents of the University of California.  All rights reserved.
   5  *
   6  * This code is derived from software contributed to Berkeley by
   7  * Diomidis Spinellis of Imperial College, University of London.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #include <sys/cdefs.h>
  35 __FBSDID("$FreeBSD$");
  36
  37 #ifndef lint
  38 static const char sccsid[] = "@(#)process.c     8.6 (Berkeley) 4/20/94";
  39 #endif
  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 <err.h>
  48 #include <errno.h>
  49 #include <fcntl.h>
  50 #include <limits.h>
  51 #include <regex.h>
  52 #include <stdio.h>
  53 #include <stdlib.h>
  54 #include <string.h>
  55 #include <unistd.h>
  56 #include <wchar.h>
  57 #include <wctype.h>
  58
  59 #include "defs.h"
  60 #include "extern.h"
  61
  62 static SPACE HS, PS, SS, YS;
  63 #define pd              PS.deleted
  64 #define ps              PS.space
  65 #define psl             PS.len
  66 #define hs              HS.space
  67 #define hsl             HS.len
  68
  69 static __inline int      applies(struct s_command *);
  70 static void              do_tr(struct s_tr *);
  71 static void              flush_appends(void);
  72 static void              lputs(char *, size_t);
  73 static __inline int      regexec_e(regex_t *, const char *, int, int, size_t);
  74 static void              regsub(SPACE *, char *, char *);
  75 static int               substitute(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, outfile); fputc('\n', outfile); }
  89
  90 void
  91 process(void)
  92 {
  93         struct s_command *cp;
  94         SPACE tspace;
  95         size_t oldpsl = 0;
  96         char *p;
  97
  98         p = NULL;
  99
 100         for (linenum = 0; mf_fgets(&PS, REPLACE);) {
 101                 pd = 0;
 102 top:
 103                 cp = prog;
 104 redirect:
 105                 while (cp != NULL) {
 106                         if (!applies(cp)) {
 107                                 cp = cp->next;
 108                                 continue;
 109                         }
 110                         switch (cp->code) {
 111                         case '{':
 112                                 cp = cp->u.c;
 113                                 goto redirect;
 114                         case 'a':
 115                                 if (appendx >= appendnum)
 116                                         if ((appends = realloc(appends,
 117                                             sizeof(struct s_appends) *
 118                                             (appendnum *= 2))) == NULL)
 119                                                 err(1, "realloc");
 120                                 appends[appendx].type = AP_STRING;
 121                                 appends[appendx].s = cp->t;
 122                                 appends[appendx].len = strlen(cp->t);
 123                                 appendx++;
 124                                 break;
 125                         case 'b':
 126                                 cp = cp->u.c;
 127                                 goto redirect;
 128                         case 'c':
 129                                 pd = 1;
 130                                 psl = 0;
 131                                 if (cp->a2 == NULL || lastaddr || lastline())
 132                                         (void)fprintf(outfile, "%s", cp->t);
 133                                 break;
 134                         case 'd':
 135                                 pd = 1;
 136                                 goto new;
 137                         case 'D':
 138                                 if (pd)
 139                                         goto new;
 140                                 if (psl == 0 ||
 141                                     (p = memchr(ps, '\n', psl)) == NULL) {
 142                                         pd = 1;
 143                                         goto new;
 144                                 } else {
 145                                         psl -= (p + 1) - ps;
 146                                         memmove(ps, p + 1, psl);
 147                                         goto top;
 148                                 }
 149                         case 'g':
 150                                 cspace(&PS, hs, hsl, REPLACE);
 151                                 break;
 152                         case 'G':
 153                                 cspace(&PS, "\n", 1, 0);
 154                                 cspace(&PS, hs, hsl, 0);
 155                                 break;
 156                         case 'h':
 157                                 cspace(&HS, ps, psl, REPLACE);
 158                                 break;
 159                         case 'H':
 160                                 cspace(&HS, "\n", 1, 0);
 161                                 cspace(&HS, ps, psl, 0);
 162                                 break;
 163                         case 'i':
 164                                 (void)fprintf(outfile, "%s", cp->t);
 165                                 break;
 166                         case 'l':
 167                                 lputs(ps, psl);
 168                                 break;
 169                         case 'n':
 170                                 if (!nflag && !pd)
 171                                         OUT(ps)
 172                                 flush_appends();
 173                                 if (!mf_fgets(&PS, REPLACE))
 174                                         exit(0);
 175                                 pd = 0;
 176                                 break;
 177                         case 'N':
 178                                 flush_appends();
 179                                 cspace(&PS, "\n", 1, 0);
 180                                 if (!mf_fgets(&PS, 0))
 181                                         exit(0);
 182                                 break;
 183                         case 'p':
 184                                 if (pd)
 185                                         break;
 186                                 OUT(ps)
 187                                 break;
 188                         case 'P':
 189                                 if (pd)
 190                                         break;
 191                                 if ((p = memchr(ps, '\n', psl)) != NULL) {
 192                                         oldpsl = psl;
 193                                         psl = p - ps;
 194                                 }
 195                                 OUT(ps)
 196                                 if (p != NULL)
 197                                         psl = oldpsl;
 198                                 break;
 199                         case 'q':
 200                                 if (!nflag && !pd)
 201                                         OUT(ps)
 202                                 flush_appends();
 203                                 exit(0);
 204                         case 'r':
 205                                 if (appendx >= appendnum)
 206                                         if ((appends = realloc(appends,
 207                                             sizeof(struct s_appends) *
 208                                             (appendnum *= 2))) == NULL)
 209                                                 err(1, "realloc");
 210                                 appends[appendx].type = AP_FILE;
 211                                 appends[appendx].s = cp->t;
 212                                 appends[appendx].len = strlen(cp->t);
 213                                 appendx++;
 214                                 break;
 215                         case 's':
 216                                 sdone |= substitute(cp);
 217                                 break;
 218                         case 't':
 219                                 if (sdone) {
 220                                         sdone = 0;
 221                                         cp = cp->u.c;
 222                                         goto redirect;
 223                                 }
 224                                 break;
 225                         case 'w':
 226                                 if (pd)
 227                                         break;
 228                                 if (cp->u.fd == -1 && (cp->u.fd = open(cp->t,
 229                                     O_WRONLY|O_APPEND|O_CREAT|O_TRUNC,
 230                                     DEFFILEMODE)) == -1)
 231                                         err(1, "%s", cp->t);
 232                                 if (write(cp->u.fd, ps, psl) != psl ||
 233                                     write(cp->u.fd, "\n", 1) != 1)
 234                                         err(1, "%s", cp->t);
 235                                 break;
 236                         case 'x':
 237                                 if (hs == NULL)
 238                                         cspace(&HS, "", 0, REPLACE);
 239                                 tspace = PS;
 240                                 PS = HS;
 241                                 HS = tspace;
 242                                 break;
 243                         case 'y':
 244                                 if (pd || psl == 0)
 245                                         break;
 246                                 do_tr(cp->u.y);
 247                                 break;
 248                         case ':':
 249                         case '}':
 250                                 break;
 251                         case '=':
 252                                 (void)fprintf(outfile, "%lu\n", linenum);
 253                         }
 254                         cp = cp->next;
 255                 } /* for all cp */
 256
 257 new:            if (!nflag && !pd)
 258                         OUT(ps)
 259                 flush_appends();
 260         } /* for all lines */
 261 }
 262
 263 /*
 264  * TRUE if the address passed matches the current program state
 265  * (lastline, linenumber, ps).
 266  */
 267 #define MATCH(a)                                                        \
 268         ((a)->type == AT_RE ? regexec_e((a)->u.r, ps, 0, 1, psl) :      \
 269             (a)->type == AT_LINE ? linenum == (a)->u.l : lastline())
 270
 271 /*
 272  * Return TRUE if the command applies to the current line.  Sets the inrange
 273  * flag to process ranges.  Interprets the non-select (``!'') flag.
 274  */
 275 static __inline int
 276 applies(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                                 r = 1;
 289                         } else if (cp->a2->type == AT_LINE &&
 290                                    linenum > cp->a2->u.l) {
 291                                 /*
 292                                  * We missed the 2nd address due to a branch,
 293                                  * so just close the range and return false.
 294                                  */
 295                                 cp->inrange = 0;
 296                                 r = 0;
 297                         } else
 298                                 r = 1;
 299                 } else if (MATCH(cp->a1)) {
 300                         /*
 301                          * If the second address is a number less than or
 302                          * equal to the line number first selected, only
 303                          * one line shall be selected.
 304                          *      -- POSIX 1003.2
 305                          */
 306                         if (cp->a2->type == AT_LINE &&
 307                             linenum >= cp->a2->u.l)
 308                                 lastaddr = 1;
 309                         else
 310                                 cp->inrange = 1;
 311                         r = 1;
 312                 } else
 313                         r = 0;
 314         else
 315                 r = MATCH(cp->a1);
 316         return (cp->nonsel ? ! r : r);
 317 }
 318
 319 /*
 320  * substitute --
 321  *      Do substitutions in the pattern space.  Currently, we build a
 322  *      copy of the new pattern space in the substitute space structure
 323  *      and then swap them.
 324  */
 325 static int
 326 substitute(struct s_command *cp)
 327 {
 328         SPACE tspace;
 329         regex_t *re;
 330         regoff_t re_off, slen;
 331         int lastempty, n;
 332         char *s;
 333
 334         s = ps;
 335         re = cp->u.s->re;
 336         if (re == NULL) {
 337                 if (defpreg != NULL && cp->u.s->maxbref > defpreg->re_nsub) {
 338                         linenum = cp->u.s->linenum;
 339                         errx(1, "%lu: %s: \\%d not defined in the RE",
 340                                         linenum, fname, cp->u.s->maxbref);
 341                 }
 342         }
 343         if (!regexec_e(re, s, 0, 0, psl))
 344                 return (0);
 345
 346         SS.len = 0;                             /* Clean substitute space. */
 347         slen = psl;
 348         n = cp->u.s->n;
 349         lastempty = 1;
 350
 351         switch (n) {
 352         case 0:                                 /* Global */
 353                 do {
 354                         if (lastempty || match[0].rm_so != match[0].rm_eo) {
 355                                 /* Locate start of replaced string. */
 356                                 re_off = match[0].rm_so;
 357                                 /* Copy leading retained string. */
 358                                 cspace(&SS, s, re_off, APPEND);
 359                                 /* Add in regular expression. */
 360                                 regsub(&SS, s, cp->u.s->new);
 361                         }
 362
 363                         /* Move past this match. */
 364                         if (match[0].rm_so != match[0].rm_eo) {
 365                                 s += match[0].rm_eo;
 366                                 slen -= match[0].rm_eo;
 367                                 lastempty = 0;
 368                         } else {
 369                                 if (match[0].rm_so < slen)
 370                                         cspace(&SS, s + match[0].rm_so, 1,
 371                                             APPEND);
 372                                 s += match[0].rm_so + 1;
 373                                 slen -= match[0].rm_so + 1;
 374                                 lastempty = 1;
 375                         }
 376                 } while (slen >= 0 && regexec_e(re, s, REG_NOTBOL, 0, slen));
 377                 /* Copy trailing retained string. */
 378                 if (slen > 0)
 379                         cspace(&SS, s, slen, APPEND);
 380                 break;
 381         default:                                /* Nth occurrence */
 382                 while (--n) {
 383                         if (match[0].rm_eo == match[0].rm_so)
 384                                 match[0].rm_eo = match[0].rm_so + 1;
 385                         s += match[0].rm_eo;
 386                         slen -= match[0].rm_eo;
 387                         if (slen < 0)
 388                                 return (0);
 389                         if (!regexec_e(re, s, REG_NOTBOL, 0, slen))
 390                                 return (0);
 391                 }
 392                 /* FALLTHROUGH */
 393         case 1:                                 /* 1st occurrence */
 394                 /* Locate start of replaced string. */
 395                 re_off = match[0].rm_so + (s - ps);
 396                 /* Copy leading retained string. */
 397                 cspace(&SS, ps, re_off, APPEND);
 398                 /* Add in regular expression. */
 399                 regsub(&SS, s, cp->u.s->new);
 400                 /* Copy trailing retained string. */
 401                 s += match[0].rm_eo;
 402                 slen -= match[0].rm_eo;
 403                 cspace(&SS, s, slen, APPEND);
 404                 break;
 405         }
 406
 407         /*
 408          * Swap the substitute space and the pattern space, and make sure
 409          * that any leftover pointers into stdio memory get lost.
 410          */
 411         tspace = PS;
 412         PS = SS;
 413         SS = tspace;
 414         SS.space = SS.back;
 415
 416         /* Handle the 'p' flag. */
 417         if (cp->u.s->p)
 418                 OUT(ps)
 419
 420         /* Handle the 'w' flag. */
 421         if (cp->u.s->wfile && !pd) {
 422                 if (cp->u.s->wfd == -1 && (cp->u.s->wfd = open(cp->u.s->wfile,
 423                     O_WRONLY|O_APPEND|O_CREAT|O_TRUNC, DEFFILEMODE)) == -1)
 424                         err(1, "%s", cp->u.s->wfile);
 425                 if (write(cp->u.s->wfd, ps, psl) != psl ||
 426                     write(cp->u.s->wfd, "\n", 1) != 1)
 427                         err(1, "%s", cp->u.s->wfile);
 428         }
 429         return (1);
 430 }
 431
 432 /*
 433  * do_tr --
 434  *      Perform translation ('y' command) in the pattern space.
 435  */
 436 static void
 437 do_tr(struct s_tr *y)
 438 {
 439         SPACE tmp;
 440         char c, *p;
 441         size_t clen, left;
 442         int i;
 443
 444         if (MB_CUR_MAX == 1) {
 445                 /*
 446                  * Single-byte encoding: perform in-place translation
 447                  * of the pattern space.
 448                  */
 449                 for (p = ps; p < &ps[psl]; p++)
 450                         *p = y->bytetab[(u_char)*p];
 451         } else {
 452                 /*
 453                  * Multi-byte encoding: perform translation into the
 454                  * translation space, then swap the translation and
 455                  * pattern spaces.
 456                  */
 457                 /* Clean translation space. */
 458                 YS.len = 0;
 459                 for (p = ps, left = psl; left > 0; p += clen, left -= clen) {
 460                         if ((c = y->bytetab[(u_char)*p]) != '\0') {
 461                                 cspace(&YS, &c, 1, APPEND);
 462                                 clen = 1;
 463                                 continue;
 464                         }
 465                         for (i = 0; i < y->nmultis; i++)
 466                                 if (left >= y->multis[i].fromlen &&
 467                                     memcmp(p, y->multis[i].from,
 468                                     y->multis[i].fromlen) == 0)
 469                                         break;
 470                         if (i < y->nmultis) {
 471                                 cspace(&YS, y->multis[i].to,
 472                                     y->multis[i].tolen, APPEND);
 473                                 clen = y->multis[i].fromlen;
 474                         } else {
 475                                 cspace(&YS, p, 1, APPEND);
 476                                 clen = 1;
 477                         }
 478                 }
 479                 /* Swap the translation space and the pattern space. */
 480                 tmp = PS;
 481                 PS = YS;
 482                 YS = tmp;
 483                 YS.space = YS.back;
 484         }
 485 }
 486
 487 /*
 488  * Flush append requests.  Always called before reading a line,
 489  * therefore it also resets the substitution done (sdone) flag.
 490  */
 491 static void
 492 flush_appends(void)
 493 {
 494         FILE *f;
 495         int count, i;
 496         char buf[8 * 1024];
 497
 498         for (i = 0; i < appendx; i++)
 499                 switch (appends[i].type) {
 500                 case AP_STRING:
 501                         fwrite(appends[i].s, sizeof(char), appends[i].len,
 502                             outfile);
 503                         break;
 504                 case AP_FILE:
 505                         /*
 506                          * Read files probably shouldn't be cached.  Since
 507                          * it's not an error to read a non-existent file,
 508                          * it's possible that another program is interacting
 509                          * with the sed script through the filesystem.  It
 510                          * would be truly bizarre, but possible.  It's probably
 511                          * not that big a performance win, anyhow.
 512                          */
 513                         if ((f = fopen(appends[i].s, "r")) == NULL)
 514                                 break;
 515                         while ((count = fread(buf, sizeof(char), sizeof(buf), f)))
 516                                 (void)fwrite(buf, sizeof(char), count, outfile);
 517                         (void)fclose(f);
 518                         break;
 519                 }
 520         if (ferror(outfile))
 521                 errx(1, "%s: %s", outfname, strerror(errno ? errno : EIO));
 522         appendx = sdone = 0;
 523 }
 524
 525 static void
 526 lputs(char *s, size_t len)
 527 {
 528         static const char escapes[] = "\\\a\b\f\r\t\v";
 529         int c, col, width;
 530         char *p;
 531         struct winsize win;
 532         static int termwidth = -1;
 533         size_t clen, i;
 534         wchar_t wc;
 535         mbstate_t mbs;
 536
 537         if (outfile != stdout)
 538                 termwidth = 60;
 539         if (termwidth == -1) {
 540                 if ((p = getenv("COLUMNS")) && *p != '\0')
 541                         termwidth = atoi(p);
 542                 else if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &win) == 0 &&
 543                     win.ws_col > 0)
 544                         termwidth = win.ws_col;
 545                 else
 546                         termwidth = 60;
 547         }
 548
 549         memset(&mbs, 0, sizeof(mbs));
 550         col = 0;
 551         while (len != 0) {
 552                 clen = mbrtowc(&wc, s, len, &mbs);
 553                 if (clen == 0)
 554                         clen = 1;
 555                 if (clen == (size_t)-1 || clen == (size_t)-2) {
 556                         wc = (unsigned char)*s;
 557                         clen = 1;
 558                         memset(&mbs, 0, sizeof(mbs));
 559                 }
 560                 if (wc == '\n') {
 561                         if (col + 1 >= termwidth)
 562                                 fprintf(outfile, "\\\n");
 563                         fputc('$', outfile);
 564                         fputc('\n', outfile);
 565                         col = 0;
 566                 } else if (iswprint(wc)) {
 567                         width = wcwidth(wc);
 568                         if (col + width >= termwidth) {
 569                                 fprintf(outfile, "\\\n");
 570                                 col = 0;
 571                         }
 572                         fwrite(s, 1, clen, outfile);
 573                         col += width;
 574                 } else if (wc != L'\0' && (c = wctob(wc)) != EOF &&
 575                     (p = strchr(escapes, c)) != NULL) {
 576                         if (col + 2 >= termwidth) {
 577                                 fprintf(outfile, "\\\n");
 578                                 col = 0;
 579                         }
 580                         fprintf(outfile, "\\%c", "\\abfrtv"[p - escapes]);
 581                         col += 2;
 582                 } else {
 583                         if (col + 4 * clen >= termwidth) {
 584                                 fprintf(outfile, "\\\n");
 585                                 col = 0;
 586                         }
 587                         for (i = 0; i < clen; i++)
 588                                 fprintf(outfile, "\\%03o",
 589                                     (int)(unsigned char)s[i]);
 590                         col += 4 * clen;
 591                 }
 592                 s += clen;
 593                 len -= clen;
 594         }
 595         if (col + 1 >= termwidth)
 596                 fprintf(outfile, "\\\n");
 597         (void)fputc('$', outfile);
 598         (void)fputc('\n', outfile);
 599         if (ferror(outfile))
 600                 errx(1, "%s: %s", outfname, strerror(errno ? errno : EIO));
 601 }
 602
 603 static __inline int
 604 regexec_e(regex_t *preg, const char *string, int eflags, int nomatch,
 605         size_t slen)
 606 {
 607         int eval;
 608
 609         if (preg == NULL) {
 610                 if (defpreg == NULL)
 611                         errx(1, "first RE may not be empty");
 612         } else
 613                 defpreg = preg;
 614
 615         /* Set anchors */
 616         match[0].rm_so = 0;
 617         match[0].rm_eo = slen;
 618
 619         eval = regexec(defpreg, string,
 620             nomatch ? 0 : maxnsub + 1, match, eflags | REG_STARTEND);
 621         switch(eval) {
 622         case 0:
 623                 return (1);
 624         case REG_NOMATCH:
 625                 return (0);
 626         }
 627         errx(1, "RE error: %s", strregerror(eval, defpreg));
 628         /* NOTREACHED */
 629 }
 630
 631 /*
 632  * regsub - perform substitutions after a regexp match
 633  * Based on a routine by Henry Spencer
 634  */
 635 static void
 636 regsub(SPACE *sp, char *string, char *src)
 637 {
 638         int len, no;
 639         char c, *dst;
 640
 641 #define NEEDSP(reqlen)                                                  \
 642         /* XXX What is the +1 for? */                                   \
 643         if (sp->len + (reqlen) + 1 >= sp->blen) {                       \
 644                 sp->blen += (reqlen) + 1024;                            \
 645                 if ((sp->space = sp->back = realloc(sp->back, sp->blen)) \
 646                     == NULL)                                            \
 647                         err(1, "realloc");                              \
 648                 dst = sp->space + sp->len;                              \
 649         }
 650
 651         dst = sp->space + sp->len;
 652         while ((c = *src++) != '\0') {
 653                 if (c == '&')
 654                         no = 0;
 655                 else if (c == '\\' && isdigit((unsigned char)*src))
 656                         no = *src++ - '0';
 657                 else
 658                         no = -1;
 659                 if (no < 0) {           /* Ordinary character. */
 660                         if (c == '\\' && (*src == '\\' || *src == '&'))
 661                                 c = *src++;
 662                         NEEDSP(1);
 663                         *dst++ = c;
 664                         ++sp->len;
 665                 } else if (match[no].rm_so != -1 && match[no].rm_eo != -1) {
 666                         len = match[no].rm_eo - match[no].rm_so;
 667                         NEEDSP(len);
 668                         memmove(dst, string + match[no].rm_so, len);
 669                         dst += len;
 670                         sp->len += len;
 671                 }
 672         }
 673         NEEDSP(1);
 674         *dst = '\0';
 675 }
 676
 677 /*
 678  * cspace --
 679  *      Concatenate space: append the source space to the destination space,
 680  *      allocating new space as necessary.
 681  */
 682 void
 683 cspace(SPACE *sp, const char *p, size_t len, enum e_spflag spflag)
 684 {
 685         size_t tlen;
 686
 687         /* Make sure SPACE has enough memory and ramp up quickly. */
 688         tlen = sp->len + len + 1;
 689         if (tlen > sp->blen) {
 690                 sp->blen = tlen + 1024;
 691                 if ((sp->space = sp->back = realloc(sp->back, sp->blen)) ==
 692                     NULL)
 693                         err(1, "realloc");
 694         }
 695
 696         if (spflag == REPLACE)
 697                 sp->len = 0;
 698
 699         memmove(sp->space + sp->len, p, len);
 700
 701         sp->space[sp->len += len] = '\0';
 702 }
 703
 704 /*
 705  * Close all cached opened files and report any errors
 706  */
 707 void
 708 cfclose(struct s_command *cp, struct s_command *end)
 709 {
 710
 711         for (; cp != end; cp = cp->next)
 712                 switch(cp->code) {
 713                 case 's':
 714                         if (cp->u.s->wfd != -1 && close(cp->u.s->wfd))
 715                                 err(1, "%s", cp->u.s->wfile);
 716                         cp->u.s->wfd = -1;
 717                         break;
 718                 case 'w':
 719                         if (cp->u.fd != -1 && close(cp->u.fd))
 720                                 err(1, "%s", cp->t);
 721                         cp->u.fd = -1;
 722                         break;
 723                 case '{':
 724                         cfclose(cp->u.c, cp->next);
 725                         break;
 726                 }
 727 }