ex/ex_subst.c

   1 /*-
   2  * Copyright (c) 1992, 1993, 1994
   3  *      The Regents of the University of California.  All rights reserved.
   4  * Copyright (c) 1992, 1993, 1994, 1995, 1996
   5  *      Keith Bostic.  All rights reserved.
   6  *
   7  * See the LICENSE file for redistribution information.
   8  */
   9
  10 #include "config.h"
  11
  12 #ifndef lint
  13 static const char sccsid[] = "$Id: ex_subst.c,v 10.39 1996/12/16 09:40:10 bostic Exp $ (Berkeley) $Date: 1996/12/16 09:40:10 $";
  14 #endif /* not lint */
  15
  16 #include <sys/types.h>
  17 #include <sys/queue.h>
  18 #include <sys/time.h>
  19
  20 #include <bitstring.h>
  21 #include <ctype.h>
  22 #include <errno.h>
  23 #include <limits.h>
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27 #include <unistd.h>
  28
  29 #include "../common/common.h"
  30 #include "../vi/vi.h"
  31
  32 #define SUB_FIRST       0x01            /* The 'r' flag isn't reasonable. */
  33 #define SUB_MUSTSETR    0x02            /* The 'r' flag is required. */
  34
  35 static int re_conv __P((SCR *, char **, size_t *, int *));
  36 static int re_cscope_conv __P((SCR *, char **, size_t *, int *));
  37 static int re_sub __P((SCR *,
  38                 char *, char **, size_t *, size_t *, regmatch_t [10]));
  39 static int re_tag_conv __P((SCR *, char **, size_t *, int *));
  40 static int s __P((SCR *, EXCMD *, char *, regex_t *, u_int));
  41
  42 /*
  43  * ex_s --
  44  *      [line [,line]] s[ubstitute] [[/;]pat[/;]/repl[/;] [cgr] [count] [#lp]]
  45  *
  46  *      Substitute on lines matching a pattern.
  47  *
  48  * PUBLIC: int ex_s __P((SCR *, EXCMD *));
  49  */
  50 int
  51 ex_s(sp, cmdp)
  52         SCR *sp;
  53         EXCMD *cmdp;
  54 {
  55         regex_t *re;
  56         size_t blen, len;
  57         u_int flags;
  58         int delim;
  59         char *bp, *ptrn, *rep, *p, *t;
  60
  61         /*
  62          * Skip leading white space.
  63          *
  64          * !!!
  65          * Historic vi allowed any non-alphanumeric to serve as the
  66          * substitution command delimiter.
  67          *
  68          * !!!
  69          * If the arguments are empty, it's the same as &, i.e. we
  70          * repeat the last substitution.
  71          */
  72         if (cmdp->argc == 0)
  73                 goto subagain;
  74         for (p = cmdp->argv[0]->bp,
  75             len = cmdp->argv[0]->len; len > 0; --len, ++p) {
  76                 if (!isblank(*p))
  77                         break;
  78         }
  79         if (len == 0)
  80 subagain:       return (ex_subagain(sp, cmdp));
  81
  82         delim = *p++;
  83         if (isalnum(delim) || delim == '\\')
  84                 return (s(sp, cmdp, p, &sp->subre_c, SUB_MUSTSETR));
  85
  86         /*
  87          * !!!
  88          * The full-blown substitute command reset the remembered
  89          * state of the 'c' and 'g' suffices.
  90          */
  91         sp->c_suffix = sp->g_suffix = 0;
  92
  93         /*
  94          * Get the pattern string, toss escaping characters.
  95          *
  96          * !!!
  97          * Historic vi accepted any of the following forms:
  98          *
  99          *      :s/abc/def/             change "abc" to "def"
 100          *      :s/abc/def              change "abc" to "def"
 101          *      :s/abc/                 delete "abc"
 102          *      :s/abc                  delete "abc"
 103          *
 104          * QUOTING NOTE:
 105          *
 106          * Only toss an escaping character if it escapes a delimiter.
 107          * This means that "s/A/\\\\f" replaces "A" with "\\f".  It
 108          * would be nice to be more regular, i.e. for each layer of
 109          * escaping a single escaping character is removed, but that's
 110          * not how the historic vi worked.
 111          */
 112         for (ptrn = t = p;;) {
 113                 if (p[0] == '\0' || p[0] == delim) {
 114                         if (p[0] == delim)
 115                                 ++p;
 116                         /*
 117                          * !!!
 118                          * Nul terminate the pattern string -- it's passed
 119                          * to regcomp which doesn't understand anything else.
 120                          */
 121                         *t = '\0';
 122                         break;
 123                 }
 124                 if (p[0] == '\\')
 125                         if (p[1] == delim)
 126                                 ++p;
 127                         else if (p[1] == '\\')
 128                                 *t++ = *p++;
 129                 *t++ = *p++;
 130         }
 131
 132         /*
 133          * If the pattern string is empty, use the last RE (not just the
 134          * last substitution RE).
 135          */
 136         if (*ptrn == '\0') {
 137                 if (sp->re == NULL) {
 138                         ex_emsg(sp, NULL, EXM_NOPREVRE);
 139                         return (1);
 140                 }
 141
 142                 /* Re-compile the RE if necessary. */
 143                 if (!F_ISSET(sp, SC_RE_SEARCH) &&
 144                     re_compile(sp, sp->re, sp->re_len,
 145                     NULL, NULL, &sp->re_c, SEARCH_CSEARCH | SEARCH_MSG))
 146                         return (1);
 147                 flags = 0;
 148         } else {
 149                 /*
 150                  * !!!
 151                  * Compile the RE.  Historic practice is that substitutes set
 152                  * the search direction as well as both substitute and search
 153                  * RE's.  We compile the RE twice, as we don't want to bother
 154                  * ref counting the pattern string and (opaque) structure.
 155                  */
 156                 if (re_compile(sp, ptrn, t - ptrn, &sp->re,
 157                     &sp->re_len, &sp->re_c, SEARCH_CSEARCH | SEARCH_MSG))
 158                         return (1);
 159                 if (re_compile(sp, ptrn, t - ptrn, &sp->subre,
 160                     &sp->subre_len, &sp->subre_c, SEARCH_CSUBST | SEARCH_MSG))
 161                         return (1);
 162
 163                 flags = SUB_FIRST;
 164                 sp->searchdir = FORWARD;
 165         }
 166         re = &sp->re_c;
 167
 168         /*
 169          * Get the replacement string.
 170          *
 171          * The special character & (\& if O_MAGIC not set) matches the
 172          * entire RE.  No handling of & is required here, it's done by
 173          * re_sub().
 174          *
 175          * The special character ~ (\~ if O_MAGIC not set) inserts the
 176          * previous replacement string into this replacement string.
 177          * Count ~'s to figure out how much space we need.  We could
 178          * special case nonexistent last patterns or whether or not
 179          * O_MAGIC is set, but it's probably not worth the effort.
 180          *
 181          * QUOTING NOTE:
 182          *
 183          * Only toss an escaping character if it escapes a delimiter or
 184          * if O_MAGIC is set and it escapes a tilde.
 185          *
 186          * !!!
 187          * If the entire replacement pattern is "%", then use the last
 188          * replacement pattern.  This semantic was added to vi in System
 189          * V and then percolated elsewhere, presumably around the time
 190          * that it was added to their version of ed(1).
 191          */
 192         if (p[0] == '\0' || p[0] == delim) {
 193                 if (p[0] == delim)
 194                         ++p;
 195                 if (sp->repl != NULL)
 196                         free(sp->repl);
 197                 sp->repl = NULL;
 198                 sp->repl_len = 0;
 199         } else if (p[0] == '%' && (p[1] == '\0' || p[1] == delim))
 200                 p += p[1] == delim ? 2 : 1;
 201         else {
 202                 for (rep = p, len = 0;
 203                     p[0] != '\0' && p[0] != delim; ++p, ++len)
 204                         if (p[0] == '~')
 205                                 len += sp->repl_len;
 206                 GET_SPACE_RET(sp, bp, blen, len);
 207                 for (t = bp, len = 0, p = rep;;) {
 208                         if (p[0] == '\0' || p[0] == delim) {
 209                                 if (p[0] == delim)
 210                                         ++p;
 211                                 break;
 212                         }
 213                         if (p[0] == '\\') {
 214                                 if (p[1] == delim)
 215                                         ++p;
 216                                 else if (p[1] == '\\') {
 217                                         *t++ = *p++;
 218                                         ++len;
 219                                 } else if (p[1] == '~') {
 220                                         ++p;
 221                                         if (!O_ISSET(sp, O_MAGIC))
 222                                                 goto tilde;
 223                                 }
 224                         } else if (p[0] == '~' && O_ISSET(sp, O_MAGIC)) {
 225 tilde:                          ++p;
 226                                 memcpy(t, sp->repl, sp->repl_len);
 227                                 t += sp->repl_len;
 228                                 len += sp->repl_len;
 229                                 continue;
 230                         }
 231                         *t++ = *p++;
 232                         ++len;
 233                 }
 234                 if ((sp->repl_len = len) != 0) {
 235                         if (sp->repl != NULL)
 236                                 free(sp->repl);
 237                         if ((sp->repl = malloc(len)) == NULL) {
 238                                 msgq(sp, M_SYSERR, NULL);
 239                                 FREE_SPACE(sp, bp, blen);
 240                                 return (1);
 241                         }
 242                         memcpy(sp->repl, bp, len);
 243                 }
 244                 FREE_SPACE(sp, bp, blen);
 245         }
 246         return (s(sp, cmdp, p, re, flags));
 247 }
 248
 249 /*
 250  * ex_subagain --
 251  *      [line [,line]] & [cgr] [count] [#lp]]
 252  *
 253  *      Substitute using the last substitute RE and replacement pattern.
 254  *
 255  * PUBLIC: int ex_subagain __P((SCR *, EXCMD *));
 256  */
 257 int
 258 ex_subagain(sp, cmdp)
 259         SCR *sp;
 260         EXCMD *cmdp;
 261 {
 262         if (sp->subre == NULL) {
 263                 ex_emsg(sp, NULL, EXM_NOPREVRE);
 264                 return (1);
 265         }
 266         if (!F_ISSET(sp, SC_RE_SUBST) &&
 267             re_compile(sp, sp->subre, sp->subre_len,
 268             NULL, NULL, &sp->subre_c, SEARCH_CSUBST | SEARCH_MSG))
 269                 return (1);
 270         return (s(sp,
 271             cmdp, cmdp->argc ? cmdp->argv[0]->bp : NULL, &sp->subre_c, 0));
 272 }
 273
 274 /*
 275  * ex_subtilde --
 276  *      [line [,line]] ~ [cgr] [count] [#lp]]
 277  *
 278  *      Substitute using the last RE and last substitute replacement pattern.
 279  *
 280  * PUBLIC: int ex_subtilde __P((SCR *, EXCMD *));
 281  */
 282 int
 283 ex_subtilde(sp, cmdp)
 284         SCR *sp;
 285         EXCMD *cmdp;
 286 {
 287         if (sp->re == NULL) {
 288                 ex_emsg(sp, NULL, EXM_NOPREVRE);
 289                 return (1);
 290         }
 291         if (!F_ISSET(sp, SC_RE_SEARCH) && re_compile(sp, sp->re,
 292             sp->re_len, NULL, NULL, &sp->re_c, SEARCH_CSEARCH | SEARCH_MSG))
 293                 return (1);
 294         return (s(sp,
 295             cmdp, cmdp->argc ? cmdp->argv[0]->bp : NULL, &sp->re_c, 0));
 296 }
 297
 298 /*
 299  * s --
 300  * Do the substitution.  This stuff is *really* tricky.  There are lots of
 301  * special cases, and general nastiness.  Don't mess with it unless you're
 302  * pretty confident.
 303  *
 304  * The nasty part of the substitution is what happens when the replacement
 305  * string contains newlines.  It's a bit tricky -- consider the information
 306  * that has to be retained for "s/f\(o\)o/^M\1^M\1/".  The solution here is
 307  * to build a set of newline offsets which we use to break the line up later,
 308  * when the replacement is done.  Don't change it unless you're *damned*
 309  * confident.
 310  */
 311 #define NEEDNEWLINE(sp) {                                               \
 312         if (sp->newl_len == sp->newl_cnt) {                             \
 313                 sp->newl_len += 25;                                     \
 314                 REALLOC(sp, sp->newl, size_t *,                         \
 315                     sp->newl_len * sizeof(size_t));                     \
 316                 if (sp->newl == NULL) {                                 \
 317                         sp->newl_len = 0;                               \
 318                         return (1);                                     \
 319                 }                                                       \
 320         }                                                               \
 321 }
 322
 323 #define BUILD(sp, l, len) {                                             \
 324         if (lbclen + (len) > lblen) {                                   \
 325                 lblen += MAX(lbclen + (len), 256);                      \
 326                 REALLOC(sp, lb, char *, lblen);                         \
 327                 if (lb == NULL) {                                       \
 328                         lbclen = 0;                                     \
 329                         return (1);                                     \
 330                 }                                                       \
 331         }                                                               \
 332         memcpy(lb + lbclen, l, len);                                    \
 333         lbclen += len;                                                  \
 334 }
 335
 336 #define NEEDSP(sp, len, pnt) {                                          \
 337         if (lbclen + (len) > lblen) {                                   \
 338                 lblen += MAX(lbclen + (len), 256);                      \
 339                 REALLOC(sp, lb, char *, lblen);                         \
 340                 if (lb == NULL) {                                       \
 341                         lbclen = 0;                                     \
 342                         return (1);                                     \
 343                 }                                                       \
 344                 pnt = lb + lbclen;                                      \
 345         }                                                               \
 346 }
 347
 348 static int
 349 s(sp, cmdp, s, re, flags)
 350         SCR *sp;
 351         EXCMD *cmdp;
 352         char *s;
 353         regex_t *re;
 354         u_int flags;
 355 {
 356         EVENT ev;
 357         MARK from, to;
 358         TEXTH tiq;
 359         recno_t elno, lno, slno;
 360         regmatch_t match[10];
 361         size_t blen, cnt, last, lbclen, lblen, len, llen;
 362         size_t offset, saved_offset, scno;
 363         int cflag, lflag, nflag, pflag, rflag;
 364         int didsub, do_eol_match, eflags, empty_ok, eval;
 365         int linechanged, matched, quit, rval;
 366         char *bp, *lb;
 367
 368         NEEDFILE(sp, cmdp);
 369
 370         slno = sp->lno;
 371         scno = sp->cno;
 372
 373         /*
 374          * !!!
 375          * Historically, the 'g' and 'c' suffices were always toggled as flags,
 376          * so ":s/A/B/" was the same as ":s/A/B/ccgg".  If O_EDCOMPATIBLE was
 377          * not set, they were initialized to 0 for all substitute commands.  If
 378          * O_EDCOMPATIBLE was set, they were initialized to 0 only if the user
 379          * specified substitute/replacement patterns (see ex_s()).
 380          */
 381         if (!O_ISSET(sp, O_EDCOMPATIBLE))
 382                 sp->c_suffix = sp->g_suffix = 0;
 383
 384         /*
 385          * Historic vi permitted the '#', 'l' and 'p' options in vi mode, but
 386          * it only displayed the last change.  I'd disallow them, but they are
 387          * useful in combination with the [v]global commands.  In the current
 388          * model the problem is combining them with the 'c' flag -- the screen
 389          * would have to flip back and forth between the confirm screen and the
 390          * ex print screen, which would be pretty awful.  We do display all
 391          * changes, though, for what that's worth.
 392          *
 393          * !!!
 394          * Historic vi was fairly strict about the order of "options", the
 395          * count, and "flags".  I'm somewhat fuzzy on the difference between
 396          * options and flags, anyway, so this is a simpler approach, and we
 397          * just take it them in whatever order the user gives them.  (The ex
 398          * usage statement doesn't reflect this.)
 399          */
 400         cflag = lflag = nflag = pflag = rflag = 0;
 401         if (s == NULL)
 402                 goto noargs;
 403         for (lno = OOBLNO; *s != '\0'; ++s)
 404                 switch (*s) {
 405                 case ' ':
 406                 case '\t':
 407                         continue;
 408                 case '+':
 409                         ++cmdp->flagoff;
 410                         break;
 411                 case '-':
 412                         --cmdp->flagoff;
 413                         break;
 414                 case '0': case '1': case '2': case '3': case '4':
 415                 case '5': case '6': case '7': case '8': case '9':
 416                         if (lno != OOBLNO)
 417                                 goto usage;
 418                         errno = 0;
 419                         lno = strtoul(s, &s, 10);
 420                         if (*s == '\0')         /* Loop increment correction. */
 421                                 --s;
 422                         if (errno == ERANGE) {
 423                                 if (lno == LONG_MAX)
 424                                         msgq(sp, M_ERR, "153|Count overflow");
 425                                 else if (lno == LONG_MIN)
 426                                         msgq(sp, M_ERR, "154|Count underflow");
 427                                 else
 428                                         msgq(sp, M_SYSERR, NULL);
 429                                 return (1);
 430                         }
 431                         /*
 432                          * In historic vi, the count was inclusive from the
 433                          * second address.
 434                          */
 435                         cmdp->addr1.lno = cmdp->addr2.lno;
 436                         cmdp->addr2.lno += lno - 1;
 437                         if (!db_exist(sp, cmdp->addr2.lno) &&
 438                             db_last(sp, &cmdp->addr2.lno))
 439                                 return (1);
 440                         break;
 441                 case '#':
 442                         nflag = 1;
 443                         break;
 444                 case 'c':
 445                         sp->c_suffix = !sp->c_suffix;
 446
 447                         /* Ex text structure initialization. */
 448                         if (F_ISSET(sp, SC_EX)) {
 449                                 memset(&tiq, 0, sizeof(TEXTH));
 450                                 CIRCLEQ_INIT(&tiq);
 451                         }
 452                         break;
 453                 case 'g':
 454                         sp->g_suffix = !sp->g_suffix;
 455                         break;
 456                 case 'l':
 457                         lflag = 1;
 458                         break;
 459                 case 'p':
 460                         pflag = 1;
 461                         break;
 462                 case 'r':
 463                         if (LF_ISSET(SUB_FIRST)) {
 464                                 msgq(sp, M_ERR,
 465                     "155|Regular expression specified; r flag meaningless");
 466                                 return (1);
 467                         }
 468                         if (!F_ISSET(sp, SC_RE_SEARCH)) {
 469                                 ex_emsg(sp, NULL, EXM_NOPREVRE);
 470                                 return (1);
 471                         }
 472                         rflag = 1;
 473                         re = &sp->re_c;
 474                         break;
 475                 default:
 476                         goto usage;
 477                 }
 478
 479         if (*s != '\0' || !rflag && LF_ISSET(SUB_MUSTSETR)) {
 480 usage:          ex_emsg(sp, cmdp->cmd->usage, EXM_USAGE);
 481                 return (1);
 482         }
 483
 484 noargs: if (F_ISSET(sp, SC_VI) && sp->c_suffix && (lflag || nflag || pflag)) {
 485                 msgq(sp, M_ERR,
 486 "156|The #, l and p flags may not be combined with the c flag in vi mode");
 487                 return (1);
 488         }
 489
 490         /*
 491          * bp:          if interactive, line cache
 492          * blen:        if interactive, line cache length
 493          * lb:          build buffer pointer.
 494          * lbclen:      current length of built buffer.
 495          * lblen;       length of build buffer.
 496          */
 497         bp = lb = NULL;
 498         blen = lbclen = lblen = 0;
 499
 500         /* For each line... */
 501         for (matched = quit = 0, lno = cmdp->addr1.lno,
 502             elno = cmdp->addr2.lno; !quit && lno <= elno; ++lno) {
 503
 504                 /* Someone's unhappy, time to stop. */
 505                 if (INTERRUPTED(sp))
 506                         break;
 507
 508                 /* Get the line. */
 509                 if (db_get(sp, lno, DBG_FATAL, &s, &llen))
 510                         goto err;
 511
 512                 /*
 513                  * Make a local copy if doing confirmation -- when calling
 514                  * the confirm routine we're likely to lose the cached copy.
 515                  */
 516                 if (sp->c_suffix) {
 517                         if (bp == NULL) {
 518                                 GET_SPACE_RET(sp, bp, blen, llen);
 519                         } else
 520                                 ADD_SPACE_RET(sp, bp, blen, llen);
 521                         memcpy(bp, s, llen);
 522                         s = bp;
 523                 }
 524
 525                 /* Start searching from the beginning. */
 526                 offset = 0;
 527                 len = llen;
 528
 529                 /* Reset the build buffer offset. */
 530                 lbclen = 0;
 531
 532                 /* Reset empty match flag. */
 533                 empty_ok = 1;
 534
 535                 /*
 536                  * We don't want to have to do a setline if the line didn't
 537                  * change -- keep track of whether or not this line changed.
 538                  * If doing confirmations, don't want to keep setting the
 539                  * line if change is refused -- keep track of substitutions.
 540                  */
 541                 didsub = linechanged = 0;
 542
 543                 /* New line, do an EOL match. */
 544                 do_eol_match = 1;
 545
 546                 /* It's not nul terminated, but we pretend it is. */
 547                 eflags = REG_STARTEND;
 548
 549                 /*
 550                  * The search area is from s + offset to the EOL.
 551                  *
 552                  * Generally, match[0].rm_so is the offset of the start
 553                  * of the match from the start of the search, and offset
 554                  * is the offset of the start of the last search.
 555                  */
 556 nextmatch:      match[0].rm_so = 0;
 557                 match[0].rm_eo = len;
 558
 559                 /* Get the next match. */
 560                 eval = regexec(re, (char *)s + offset, 10, match, eflags);
 561
 562                 /*
 563                  * There wasn't a match or if there was an error, deal with
 564                  * it.  If there was a previous match in this line, resolve
 565                  * the changes into the database.  Otherwise, just move on.
 566                  */
 567                 if (eval == REG_NOMATCH)
 568                         goto endmatch;
 569                 if (eval != 0) {
 570                         re_error(sp, eval, re);
 571                         goto err;
 572                 }
 573                 matched = 1;
 574
 575                 /* Only the first search can match an anchored expression. */
 576                 eflags |= REG_NOTBOL;
 577
 578                 /*
 579                  * !!!
 580                  * It's possible to match 0-length strings -- for example, the
 581                  * command s;a*;X;, when matched against the string "aabb" will
 582                  * result in "XbXbX", i.e. the matches are "aa", the space
 583                  * between the b's and the space between the b's and the end of
 584                  * the string.  There is a similar space between the beginning
 585                  * of the string and the a's.  The rule that we use (because vi
 586                  * historically used it) is that any 0-length match, occurring
 587                  * immediately after a match, is ignored.  Otherwise, the above
 588                  * example would have resulted in "XXbXbX".  Another example is
 589                  * incorrectly using " *" to replace groups of spaces with one
 590                  * space.
 591                  *
 592                  * The way we do this is that if we just had a successful match,
 593                  * the starting offset does not skip characters, and the match
 594                  * is empty, ignore the match and move forward.  If there's no
 595                  * more characters in the string, we were attempting to match
 596                  * after the last character, so quit.
 597                  */
 598                 if (!empty_ok && match[0].rm_so == 0 && match[0].rm_eo == 0) {
 599                         empty_ok = 1;
 600                         if (len == 0)
 601                                 goto endmatch;
 602                         BUILD(sp, s + offset, 1)
 603                         ++offset;
 604                         --len;
 605                         goto nextmatch;
 606                 }
 607
 608                 /* Confirm change. */
 609                 if (sp->c_suffix) {
 610                         /*
 611                          * Set the cursor position for confirmation.  Note,
 612                          * if we matched on a '$', the cursor may be past
 613                          * the end of line.
 614                          */
 615                         from.lno = to.lno = lno;
 616                         from.cno = match[0].rm_so + offset;
 617                         to.cno = match[0].rm_eo + offset;
 618                         /*
 619                          * Both ex and vi have to correct for a change before
 620                          * the first character in the line.
 621                          */
 622                         if (llen == 0)
 623                                 from.cno = to.cno = 0;
 624                         if (F_ISSET(sp, SC_VI)) {
 625                                 /*
 626                                  * Only vi has to correct for a change after
 627                                  * the last character in the line.
 628                                  *
 629                                  * XXX
 630                                  * It would be nice to change the vi code so
 631                                  * that we could display a cursor past EOL.
 632                                  */
 633                                 if (to.cno >= llen)
 634                                         to.cno = llen - 1;
 635                                 if (from.cno >= llen)
 636                                         from.cno = llen - 1;
 637
 638                                 sp->lno = from.lno;
 639                                 sp->cno = from.cno;
 640                                 if (vs_refresh(sp, 1))
 641                                         goto err;
 642
 643                                 vs_update(sp, msg_cat(sp,
 644                                     "169|Confirm change? [n]", NULL), NULL);
 645
 646                                 if (v_event_get(sp, &ev, 0, 0))
 647                                         goto err;
 648                                 switch (ev.e_event) {
 649                                 case E_CHARACTER:
 650                                         break;
 651                                 case E_EOF:
 652                                 case E_ERR:
 653                                 case E_INTERRUPT:
 654                                         goto lquit;
 655                                 default:
 656                                         v_event_err(sp, &ev);
 657                                         goto lquit;
 658                                 }
 659                         } else {
 660                                 if (ex_print(sp, cmdp, &from, &to, 0) ||
 661                                     ex_scprint(sp, &from, &to))
 662                                         goto lquit;
 663                                 if (ex_txt(sp, &tiq, 0, TXT_CR))
 664                                         goto err;
 665                                 ev.e_c = tiq.cqh_first->lb[0];
 666                         }
 667
 668                         switch (ev.e_c) {
 669                         case CH_YES:
 670                                 break;
 671                         default:
 672                         case CH_NO:
 673                                 didsub = 0;
 674                                 BUILD(sp, s +offset, match[0].rm_eo);
 675                                 goto skip;
 676                         case CH_QUIT:
 677                                 /* Set the quit/interrupted flags. */
 678 lquit:                          quit = 1;
 679                                 F_SET(sp->gp, G_INTERRUPTED);
 680
 681                                 /*
 682                                  * Resolve any changes, then return to (and
 683                                  * exit from) the main loop.
 684                                  */
 685                                 goto endmatch;
 686                         }
 687                 }
 688
 689                 /*
 690                  * Set the cursor to the last position changed, converting
 691                  * from 1-based to 0-based.
 692                  */
 693                 sp->lno = lno;
 694                 sp->cno = match[0].rm_so;
 695
 696                 /* Copy the bytes before the match into the build buffer. */
 697                 BUILD(sp, s + offset, match[0].rm_so);
 698
 699                 /* Substitute the matching bytes. */
 700                 didsub = 1;
 701                 if (re_sub(sp, s + offset, &lb, &lbclen, &lblen, match))
 702                         goto err;
 703
 704                 /* Set the change flag so we know this line was modified. */
 705                 linechanged = 1;
 706
 707                 /* Move past the matched bytes. */
 708 skip:           offset += match[0].rm_eo;
 709                 len -= match[0].rm_eo;
 710
 711                 /* A match cannot be followed by an empty pattern. */
 712                 empty_ok = 0;
 713
 714                 /*
 715                  * If doing a global change with confirmation, we have to
 716                  * update the screen.  The basic idea is to store the line
 717                  * so the screen update routines can find it, and restart.
 718                  */
 719                 if (didsub && sp->c_suffix && sp->g_suffix) {
 720                         /*
 721                          * The new search offset will be the end of the
 722                          * modified line.
 723                          */
 724                         saved_offset = lbclen;
 725
 726                         /* Copy the rest of the line. */
 727                         if (len)
 728                                 BUILD(sp, s + offset, len)
 729
 730                         /* Set the new offset. */
 731                         offset = saved_offset;
 732
 733                         /* Store inserted lines, adjusting the build buffer. */
 734                         last = 0;
 735                         if (sp->newl_cnt) {
 736                                 for (cnt = 0;
 737                                     cnt < sp->newl_cnt; ++cnt, ++lno, ++elno) {
 738                                         if (db_insert(sp, lno,
 739                                             lb + last, sp->newl[cnt] - last))
 740                                                 goto err;
 741                                         last = sp->newl[cnt] + 1;
 742                                         ++sp->rptlines[L_ADDED];
 743                                 }
 744                                 lbclen -= last;
 745                                 offset -= last;
 746                                 sp->newl_cnt = 0;
 747                         }
 748
 749                         /* Store and retrieve the line. */
 750                         if (db_set(sp, lno, lb + last, lbclen))
 751                                 goto err;
 752                         if (db_get(sp, lno, DBG_FATAL, &s, &llen))
 753                                 goto err;
 754                         ADD_SPACE_RET(sp, bp, blen, llen)
 755                         memcpy(bp, s, llen);
 756                         s = bp;
 757                         len = llen - offset;
 758
 759                         /* Restart the build. */
 760                         lbclen = 0;
 761                         BUILD(sp, s, offset);
 762
 763                         /*
 764                          * If we haven't already done the after-the-string
 765                          * match, do one.  Set REG_NOTEOL so the '$' pattern
 766                          * only matches once.
 767                          */
 768                         if (!do_eol_match)
 769                                 goto endmatch;
 770                         if (offset == len) {
 771                                 do_eol_match = 0;
 772                                 eflags |= REG_NOTEOL;
 773                         }
 774                         goto nextmatch;
 775                 }
 776
 777                 /*
 778                  * If it's a global:
 779                  *
 780                  * If at the end of the string, do a test for the after
 781                  * the string match.  Set REG_NOTEOL so the '$' pattern
 782                  * only matches once.
 783                  */
 784                 if (sp->g_suffix && do_eol_match) {
 785                         if (len == 0) {
 786                                 do_eol_match = 0;
 787                                 eflags |= REG_NOTEOL;
 788                         }
 789                         goto nextmatch;
 790                 }
 791
 792 endmatch:       if (!linechanged)
 793                         continue;
 794
 795                 /* Copy any remaining bytes into the build buffer. */
 796                 if (len)
 797                         BUILD(sp, s + offset, len)
 798
 799                 /* Store inserted lines, adjusting the build buffer. */
 800                 last = 0;
 801                 if (sp->newl_cnt) {
 802                         for (cnt = 0;
 803                             cnt < sp->newl_cnt; ++cnt, ++lno, ++elno) {
 804                                 if (db_insert(sp,
 805                                     lno, lb + last, sp->newl[cnt] - last))
 806                                         goto err;
 807                                 last = sp->newl[cnt] + 1;
 808                                 ++sp->rptlines[L_ADDED];
 809                         }
 810                         lbclen -= last;
 811                         sp->newl_cnt = 0;
 812                 }
 813
 814                 /* Store the changed line. */
 815                 if (db_set(sp, lno, lb + last, lbclen))
 816                         goto err;
 817
 818                 /* Update changed line counter. */
 819                 if (sp->rptlchange != lno) {
 820                         sp->rptlchange = lno;
 821                         ++sp->rptlines[L_CHANGED];
 822                 }
 823
 824                 /*
 825                  * !!!
 826                  * Display as necessary.  Historic practice is to only
 827                  * display the last line of a line split into multiple
 828                  * lines.
 829                  */
 830                 if (lflag || nflag || pflag) {
 831                         from.lno = to.lno = lno;
 832                         from.cno = to.cno = 0;
 833                         if (lflag)
 834                                 (void)ex_print(sp, cmdp, &from, &to, E_C_LIST);
 835                         if (nflag)
 836                                 (void)ex_print(sp, cmdp, &from, &to, E_C_HASH);
 837                         if (pflag)
 838                                 (void)ex_print(sp, cmdp, &from, &to, E_C_PRINT);
 839                 }
 840         }
 841
 842         /*
 843          * !!!
 844          * Historically, vi attempted to leave the cursor at the same place if
 845          * the substitution was done at the current cursor position.  Otherwise
 846          * it moved it to the first non-blank of the last line changed.  There
 847          * were some problems: for example, :s/$/foo/ with the cursor on the
 848          * last character of the line left the cursor on the last character, or
 849          * the & command with multiple occurrences of the matching string in the
 850          * line usually left the cursor in a fairly random position.
 851          *
 852          * We try to do the same thing, with the exception that if the user is
 853          * doing substitution with confirmation, we move to the last line about
 854          * which the user was consulted, as opposed to the last line that they
 855          * actually changed.  This prevents a screen flash if the user doesn't
 856          * change many of the possible lines.
 857          */
 858         if (!sp->c_suffix && (sp->lno != slno || sp->cno != scno)) {
 859                 sp->cno = 0;
 860                 (void)nonblank(sp, sp->lno, &sp->cno);
 861         }
 862
 863         /*
 864          * If not in a global command, and nothing matched, say so.
 865          * Else, if none of the lines displayed, put something up.
 866          */
 867         rval = 0;
 868         if (!matched) {
 869                 if (!F_ISSET(sp, SC_EX_GLOBAL)) {
 870                         msgq(sp, M_ERR, "157|No match found");
 871                         goto err;
 872                 }
 873         } else if (!lflag && !nflag && !pflag)
 874                 F_SET(cmdp, E_AUTOPRINT);
 875
 876         if (0) {
 877 err:            rval = 1;
 878         }
 879
 880         if (bp != NULL)
 881                 FREE_SPACE(sp, bp, blen);
 882         if (lb != NULL)
 883                 free(lb);
 884         return (rval);
 885 }
 886
 887 /*
 888  * re_compile --
 889  *      Compile the RE.
 890  *
 891  * PUBLIC: int re_compile __P((SCR *,
 892  * PUBLIC:     char *, size_t, char **, size_t *, regex_t *, u_int));
 893  */
 894 int
 895 re_compile(sp, ptrn, plen, ptrnp, lenp, rep, flags)
 896         SCR *sp;
 897         char *ptrn, **ptrnp;
 898         size_t plen, *lenp;
 899         regex_t *rep;
 900         u_int flags;
 901 {
 902         size_t len;
 903         int reflags, replaced, rval;
 904         char *p;
 905
 906         /* Set RE flags. */
 907         reflags = 0;
 908         if (LF_ISSET(SEARCH_EXTEND))
 909                 reflags |= REG_EXTENDED;
 910         if (LF_ISSET(SEARCH_IC))
 911                 reflags |= REG_ICASE;
 912         if (LF_ISSET(SEARCH_LITERAL))
 913                 reflags |= REG_NOSPEC;
 914         if (!LF_ISSET(SEARCH_NOOPT | SEARCH_CSCOPE | SEARCH_TAG)) {
 915                 if (O_ISSET(sp, O_EXTENDED))
 916                         reflags |= REG_EXTENDED;
 917                 if (O_ISSET(sp, O_IGNORECASE))
 918                         reflags |= REG_ICASE;
 919                 if (O_ISSET(sp, O_ICLOWER))
 920                         goto iclower;
 921         }
 922         if (LF_ISSET(SEARCH_ICL)) {
 923 iclower:        for (p = ptrn, len = plen; len > 0; ++p, --len)
 924                         if (isupper(*p))
 925                                 break;
 926                 if (len == 0)
 927                         reflags |= REG_ICASE;
 928         }
 929
 930         /* If we're replacing a saved value, clear the old one. */
 931         if (LF_ISSET(SEARCH_CSEARCH) && F_ISSET(sp, SC_RE_SEARCH)) {
 932                 regfree(&sp->re_c);
 933                 F_CLR(sp, SC_RE_SEARCH);
 934         }
 935         if (LF_ISSET(SEARCH_CSUBST) && F_ISSET(sp, SC_RE_SUBST)) {
 936                 regfree(&sp->subre_c);
 937                 F_CLR(sp, SC_RE_SUBST);
 938         }
 939
 940         /*
 941          * If we're saving the string, it's a pattern we haven't seen before,
 942          * so convert the vi-style RE's to POSIX 1003.2 RE's.  Save a copy for
 943          * later recompilation.   Free any previously saved value.
 944          */
 945         if (ptrnp != NULL) {
 946                 replaced = 0;
 947                 if (LF_ISSET(SEARCH_CSCOPE)) {
 948                         if (re_cscope_conv(sp, &ptrn, &plen, &replaced))
 949                                 return (1);
 950                         /*
 951                          * XXX
 952                          * Currently, the match-any-<blank> expression used in
 953                          * re_cscope_conv() requires extended RE's.  This may
 954                          * not be right or safe.
 955                          */
 956                         reflags |= REG_EXTENDED;
 957                 } else if (LF_ISSET(SEARCH_TAG)) {
 958                         if (re_tag_conv(sp, &ptrn, &plen, &replaced))
 959                                 return (1);
 960                 } else if (!LF_ISSET(SEARCH_LITERAL))
 961                         if (re_conv(sp, &ptrn, &plen, &replaced))
 962                                 return (1);
 963
 964                 /* Discard previous pattern. */
 965                 if (*ptrnp != NULL) {
 966                         free(*ptrnp);
 967                         *ptrnp = NULL;
 968                 }
 969                 if (lenp != NULL)
 970                         *lenp = plen;
 971
 972                 /*
 973                  * Copy the string into allocated memory.
 974                  *
 975                  * XXX
 976                  * Regcomp isn't 8-bit clean, so the pattern is nul-terminated
 977                  * for now.  There's just no other solution.
 978                  */
 979                 MALLOC(sp, *ptrnp, char *, plen + 1);
 980                 if (*ptrnp != NULL) {
 981                         memcpy(*ptrnp, ptrn, plen);
 982                         (*ptrnp)[plen] = '\0';
 983                 }
 984
 985                 /* Free up conversion-routine-allocated memory. */
 986                 if (replaced)
 987                         FREE_SPACE(sp, ptrn, 0);
 988
 989                 if (*ptrnp == NULL)
 990                         return (1);
 991
 992                 ptrn = *ptrnp;
 993         }
 994
 995         /*
 996          * XXX
 997          * Regcomp isn't 8-bit clean, so we just lost if the pattern
 998          * contained a nul.  Bummer!
 999          */
1000         if ((rval = regcomp(rep, ptrn, /* plen, */ reflags)) != 0) {
1001                 if (LF_ISSET(SEARCH_MSG))
1002                         re_error(sp, rval, rep);
1003                 return (1);
1004         }
1005
1006         if (LF_ISSET(SEARCH_CSEARCH))
1007                 F_SET(sp, SC_RE_SEARCH);
1008         if (LF_ISSET(SEARCH_CSUBST))
1009                 F_SET(sp, SC_RE_SUBST);
1010
1011         return (0);
1012 }
1013
1014 /*
1015  * re_conv --
1016  *      Convert vi's regular expressions into something that the
1017  *      the POSIX 1003.2 RE functions can handle.
1018  *
1019  * There are three conversions we make to make vi's RE's (specifically
1020  * the global, search, and substitute patterns) work with POSIX RE's.
1021  *
1022  * 1: If O_MAGIC is not set, strip backslashes from the magic character
1023  *    set (.[*~) that have them, and add them to the ones that don't.
1024  * 2: If O_MAGIC is not set, the string "\~" is replaced with the text
1025  *    from the last substitute command's replacement string.  If O_MAGIC
1026  *    is set, it's the string "~".
1027  * 3: The pattern \<ptrn\> does "word" searches, convert it to use the
1028  *    new RE escapes.
1029  *
1030  * !!!/XXX
1031  * This doesn't exactly match the historic behavior of vi because we do
1032  * the ~ substitution before calling the RE engine, so magic characters
1033  * in the replacement string will be expanded by the RE engine, and they
1034  * weren't historically.  It's a bug.
1035  */
1036 static int
1037 re_conv(sp, ptrnp, plenp, replacedp)
1038         SCR *sp;
1039         char **ptrnp;
1040         size_t *plenp;
1041         int *replacedp;
1042 {
1043         size_t blen, len, needlen;
1044         int magic;
1045         char *bp, *p, *t;
1046
1047         /*
1048          * First pass through, we figure out how much space we'll need.
1049          * We do it in two passes, on the grounds that most of the time
1050          * the user is doing a search and won't have magic characters.
1051          * That way we can skip most of the memory allocation and copies.
1052          */
1053         magic = 0;
1054         for (p = *ptrnp, len = *plenp, needlen = 0; len > 0; ++p, --len)
1055                 switch (*p) {
1056                 case '\\':
1057                         if (len > 1) {
1058                                 --len;
1059                                 switch (*++p) {
1060                                 case '<':
1061                                         magic = 1;
1062                                         needlen += sizeof(RE_WSTART);
1063                                         break;
1064                                 case '>':
1065                                         magic = 1;
1066                                         needlen += sizeof(RE_WSTOP);
1067                                         break;
1068                                 case '~':
1069                                         if (!O_ISSET(sp, O_MAGIC)) {
1070                                                 magic = 1;
1071                                                 needlen += sp->repl_len;
1072                                         }
1073                                         break;
1074                                 case '.':
1075                                 case '[':
1076                                 case '*':
1077                                         if (!O_ISSET(sp, O_MAGIC)) {
1078                                                 magic = 1;
1079                                                 needlen += 1;
1080                                         }
1081                                         break;
1082                                 default:
1083                                         needlen += 2;
1084                                 }
1085                         } else
1086                                 needlen += 1;
1087                         break;
1088                 case '~':
1089                         if (O_ISSET(sp, O_MAGIC)) {
1090                                 magic = 1;
1091                                 needlen += sp->repl_len;
1092                         }
1093                         break;
1094                 case '.':
1095                 case '[':
1096                 case '*':
1097                         if (!O_ISSET(sp, O_MAGIC)) {
1098                                 magic = 1;
1099                                 needlen += 2;
1100                         }
1101                         break;
1102                 default:
1103                         needlen += 1;
1104                         break;
1105                 }
1106
1107         if (!magic) {
1108                 *replacedp = 0;
1109                 return (0);
1110         }
1111
1112         /* Get enough memory to hold the final pattern. */
1113         *replacedp = 1;
1114         GET_SPACE_RET(sp, bp, blen, needlen);
1115
1116         for (p = *ptrnp, len = *plenp, t = bp; len > 0; ++p, --len)
1117                 switch (*p) {
1118                 case '\\':
1119                         if (len > 1) {
1120                                 --len;
1121                                 switch (*++p) {
1122                                 case '<':
1123                                         memcpy(t,
1124                                             RE_WSTART, sizeof(RE_WSTART) - 1);
1125                                         t += sizeof(RE_WSTART) - 1;
1126                                         break;
1127                                 case '>':
1128                                         memcpy(t,
1129                                             RE_WSTOP, sizeof(RE_WSTOP) - 1);
1130                                         t += sizeof(RE_WSTOP) - 1;
1131                                         break;
1132                                 case '~':
1133                                         if (O_ISSET(sp, O_MAGIC))
1134                                                 *t++ = '~';
1135                                         else {
1136                                                 memcpy(t,
1137                                                     sp->repl, sp->repl_len);
1138                                                 t += sp->repl_len;
1139                                         }
1140                                         break;
1141                                 case '.':
1142                                 case '[':
1143                                 case '*':
1144                                         if (O_ISSET(sp, O_MAGIC))
1145                                                 *t++ = '\\';
1146                                         *t++ = *p;
1147                                         break;
1148                                 default:
1149                                         *t++ = '\\';
1150                                         *t++ = *p;
1151                                 }
1152                         } else
1153                                 *t++ = '\\';
1154                         break;
1155                 case '~':
1156                         if (O_ISSET(sp, O_MAGIC)) {
1157                                 memcpy(t, sp->repl, sp->repl_len);
1158                                 t += sp->repl_len;
1159                         } else
1160                                 *t++ = '~';
1161                         break;
1162                 case '.':
1163                 case '[':
1164                 case '*':
1165                         if (!O_ISSET(sp, O_MAGIC))
1166                                 *t++ = '\\';
1167                         *t++ = *p;
1168                         break;
1169                 default:
1170                         *t++ = *p;
1171                         break;
1172                 }
1173
1174         *ptrnp = bp;
1175         *plenp = t - bp;
1176         return (0);
1177 }
1178
1179 /*
1180  * re_tag_conv --
1181  *      Convert a tags search path into something that the POSIX
1182  *      1003.2 RE functions can handle.
1183  */
1184 static int
1185 re_tag_conv(sp, ptrnp, plenp, replacedp)
1186         SCR *sp;
1187         char **ptrnp;
1188         size_t *plenp;
1189         int *replacedp;
1190 {
1191         size_t blen, len;
1192         int lastdollar;
1193         char *bp, *p, *t;
1194
1195         len = *plenp;
1196
1197         /* Max memory usage is 2 times the length of the string. */
1198         *replacedp = 1;
1199         GET_SPACE_RET(sp, bp, blen, len * 2);
1200
1201         p = *ptrnp;
1202         t = bp;
1203
1204         /* If the last character is a '/' or '?', we just strip it. */
1205         if (len > 0 && (p[len - 1] == '/' || p[len - 1] == '?'))
1206                 --len;
1207
1208         /* If the next-to-last or last character is a '$', it's magic. */
1209         if (len > 0 && p[len - 1] == '$') {
1210                 --len;
1211                 lastdollar = 1;
1212         } else
1213                 lastdollar = 0;
1214
1215         /* If the first character is a '/' or '?', we just strip it. */
1216         if (len > 0 && (p[0] == '/' || p[0] == '?')) {
1217                 ++p;
1218                 --len;
1219         }
1220
1221         /* If the first or second character is a '^', it's magic. */
1222         if (p[0] == '^') {
1223                 *t++ = *p++;
1224                 --len;
1225         }
1226
1227         /*
1228          * Escape every other magic character we can find, meanwhile stripping
1229          * the backslashes ctags inserts when escaping the search delimiter
1230          * characters.
1231          */
1232         for (; len > 0; --len) {
1233                 if (p[0] == '\\' && (p[1] == '/' || p[1] == '?')) {
1234                         ++p;
1235                         --len;
1236                 } else if (strchr("^.[]$*", p[0]))
1237                         *t++ = '\\';
1238                 *t++ = *p++;
1239         }
1240         if (lastdollar)
1241                 *t++ = '$';
1242
1243         *ptrnp = bp;
1244         *plenp = t - bp;
1245         return (0);
1246 }
1247
1248 /*
1249  * re_cscope_conv --
1250  *       Convert a cscope search path into something that the POSIX
1251  *      1003.2 RE functions can handle.
1252  */
1253 static int
1254 re_cscope_conv(sp, ptrnp, plenp, replacedp)
1255         SCR *sp;
1256         char **ptrnp;
1257         size_t *plenp;
1258         int *replacedp;
1259 {
1260         size_t blen, len, nspaces;
1261         char *bp, *p, *t;
1262
1263         /*
1264          * Each space in the source line printed by cscope represents an
1265          * arbitrary sequence of spaces, tabs, and comments.
1266          */
1267 #define CSCOPE_RE_SPACE         "([ \t]|/\\*([^*]|\\*/)*\\*/)*"
1268         for (nspaces = 0, p = *ptrnp, len = *plenp; len > 0; ++p, --len)
1269                 if (*p == ' ')
1270                         ++nspaces;
1271
1272         /*
1273          * Allocate plenty of space:
1274          *      the string, plus potential escaping characters;
1275          *      nspaces + 2 copies of CSCOPE_RE_SPACE;
1276          *      ^, $, nul terminator characters.
1277          */
1278         *replacedp = 1;
1279         len = (p - *ptrnp) * 2 + (nspaces + 2) * sizeof(CSCOPE_RE_SPACE) + 3;
1280         GET_SPACE_RET(sp, bp, blen, len);
1281
1282         p = *ptrnp;
1283         t = bp;
1284
1285         *t++ = '^';
1286         memcpy(t, CSCOPE_RE_SPACE, sizeof(CSCOPE_RE_SPACE) - 1);
1287         t += sizeof(CSCOPE_RE_SPACE) - 1;
1288
1289         for (len = *plenp; len > 0; ++p, --len)
1290                 if (*p == ' ') {
1291                         memcpy(t, CSCOPE_RE_SPACE, sizeof(CSCOPE_RE_SPACE) - 1);
1292                         t += sizeof(CSCOPE_RE_SPACE) - 1;
1293                 } else {
1294                         if (strchr("\\^.[]$*+?()|{}", *p))
1295                                 *t++ = '\\';
1296                         *t++ = *p;
1297                 }
1298
1299         memcpy(t, CSCOPE_RE_SPACE, sizeof(CSCOPE_RE_SPACE) - 1);
1300         t += sizeof(CSCOPE_RE_SPACE) - 1;
1301         *t++ = '$';
1302
1303         *ptrnp = bp;
1304         *plenp = t - bp;
1305         return (0);
1306 }
1307
1308 /*
1309  * re_error --
1310  *      Report a regular expression error.
1311  *
1312  * PUBLIC: void re_error __P((SCR *, int, regex_t *));
1313  */
1314 void
1315 re_error(sp, errcode, preg)
1316         SCR *sp;
1317         int errcode;
1318         regex_t *preg;
1319 {
1320         size_t s;
1321         char *oe;
1322
1323         s = regerror(errcode, preg, "", 0);
1324         if ((oe = malloc(s)) == NULL)
1325                 msgq(sp, M_SYSERR, NULL);
1326         else {
1327                 (void)regerror(errcode, preg, oe, s);
1328                 msgq(sp, M_ERR, "RE error: %s", oe);
1329                 free(oe);
1330         }
1331 }
1332
1333 /*
1334  * re_sub --
1335  *      Do the substitution for a regular expression.
1336  */
1337 static int
1338 re_sub(sp, ip, lbp, lbclenp, lblenp, match)
1339         SCR *sp;
1340         char *ip;                       /* Input line. */
1341         char **lbp;
1342         size_t *lbclenp, *lblenp;
1343         regmatch_t match[10];
1344 {
1345         enum { C_NOTSET, C_LOWER, C_ONELOWER, C_ONEUPPER, C_UPPER } conv;
1346         size_t lbclen, lblen;           /* Local copies. */
1347         size_t mlen;                    /* Match length. */
1348         size_t rpl;                     /* Remaining replacement length. */
1349         char *rp;                       /* Replacement pointer. */
1350         int ch;
1351         int no;                         /* Match replacement offset. */
1352         char *p, *t;                    /* Buffer pointers. */
1353         char *lb;                       /* Local copies. */
1354
1355         lb = *lbp;                      /* Get local copies. */
1356         lbclen = *lbclenp;
1357         lblen = *lblenp;
1358
1359         /*
1360          * QUOTING NOTE:
1361          *
1362          * There are some special sequences that vi provides in the
1363          * replacement patterns.
1364          *       & string the RE matched (\& if nomagic set)
1365          *      \# n-th regular subexpression
1366          *      \E end \U, \L conversion
1367          *      \e end \U, \L conversion
1368          *      \l convert the next character to lower-case
1369          *      \L convert to lower-case, until \E, \e, or end of replacement
1370          *      \u convert the next character to upper-case
1371          *      \U convert to upper-case, until \E, \e, or end of replacement
1372          *
1373          * Otherwise, since this is the lowest level of replacement, discard
1374          * all escaping characters.  This (hopefully) matches historic practice.
1375          */
1376 #define OUTCH(ch, nltrans) {                                            \
1377         CHAR_T __ch = (ch);                                             \
1378         u_int __value = KEY_VAL(sp, __ch);                              \
1379         if (nltrans && (__value == K_CR || __value == K_NL)) {          \
1380                 NEEDNEWLINE(sp);                                        \
1381                 sp->newl[sp->newl_cnt++] = lbclen;                      \
1382         } else if (conv != C_NOTSET) {                                  \
1383                 switch (conv) {                                         \
1384                 case C_ONELOWER:                                        \
1385                         conv = C_NOTSET;                                \
1386                         /* FALLTHROUGH */                               \
1387                 case C_LOWER:                                           \
1388                         if (isupper(__ch))                              \
1389                                 __ch = tolower(__ch);                   \
1390                         break;                                          \
1391                 case C_ONEUPPER:                                        \
1392                         conv = C_NOTSET;                                \
1393                         /* FALLTHROUGH */                               \
1394                 case C_UPPER:                                           \
1395                         if (islower(__ch))                              \
1396                                 __ch = toupper(__ch);                   \
1397                         break;                                          \
1398                 default:                                                \
1399                         abort();                                        \
1400                 }                                                       \
1401         }                                                               \
1402         NEEDSP(sp, 1, p);                                               \
1403         *p++ = __ch;                                                    \
1404         ++lbclen;                                                       \
1405 }
1406         conv = C_NOTSET;
1407         for (rp = sp->repl, rpl = sp->repl_len, p = lb + lbclen; rpl--;) {
1408                 switch (ch = *rp++) {
1409                 case '&':
1410                         if (O_ISSET(sp, O_MAGIC)) {
1411                                 no = 0;
1412                                 goto subzero;
1413                         }
1414                         break;
1415                 case '\\':
1416                         if (rpl == 0)
1417                                 break;
1418                         --rpl;
1419                         switch (ch = *rp) {
1420                         case '&':
1421                                 ++rp;
1422                                 if (!O_ISSET(sp, O_MAGIC)) {
1423                                         no = 0;
1424                                         goto subzero;
1425                                 }
1426                                 break;
1427                         case '0': case '1': case '2': case '3': case '4':
1428                         case '5': case '6': case '7': case '8': case '9':
1429                                 no = *rp++ - '0';
1430 subzero:                        if (match[no].rm_so == -1 ||
1431                                     match[no].rm_eo == -1)
1432                                         break;
1433                                 mlen = match[no].rm_eo - match[no].rm_so;
1434                                 for (t = ip + match[no].rm_so; mlen--; ++t)
1435                                         OUTCH(*t, 0);
1436                                 continue;
1437                         case 'e':
1438                         case 'E':
1439                                 ++rp;
1440                                 conv = C_NOTSET;
1441                                 continue;
1442                         case 'l':
1443                                 ++rp;
1444                                 conv = C_ONELOWER;
1445                                 continue;
1446                         case 'L':
1447                                 ++rp;
1448                                 conv = C_LOWER;
1449                                 continue;
1450                         case 'u':
1451                                 ++rp;
1452                                 conv = C_ONEUPPER;
1453                                 continue;
1454                         case 'U':
1455                                 ++rp;
1456                                 conv = C_UPPER;
1457                                 continue;
1458                         default:
1459                                 ++rp;
1460                                 break;
1461                         }
1462                 }
1463                 OUTCH(ch, 1);
1464         }
1465
1466         *lbp = lb;                      /* Update caller's information. */
1467         *lbclenp = lbclen;
1468         *lblenp = lblen;
1469         return (0);
1470 }