xref: /freebsd/contrib/nvi/ex/ex_subst.c (revision cc68614da8232d8baaca0ae0d0dd8f890f06623e)
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 #include <sys/types.h>
13 #include <sys/queue.h>
14 #include <sys/time.h>
15 
16 #include <bitstring.h>
17 #include <ctype.h>
18 #include <errno.h>
19 #include <limits.h>
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <string.h>
23 #include <unistd.h>
24 
25 #include "../common/common.h"
26 #include "../vi/vi.h"
27 
28 #define	SUB_FIRST	0x01		/* The 'r' flag isn't reasonable. */
29 #define	SUB_MUSTSETR	0x02		/* The 'r' flag is required. */
30 
31 static int re_conv(SCR *, CHAR_T **, size_t *, int *);
32 static int re_cscope_conv(SCR *, CHAR_T **, size_t *, int *);
33 static int re_sub(SCR *,
34 		CHAR_T *, CHAR_T **, size_t *, size_t *, regmatch_t [10]);
35 static int re_tag_conv(SCR *, CHAR_T **, size_t *, int *);
36 static int s(SCR *, EXCMD *, CHAR_T *, regex_t *, u_int);
37 
38 /*
39  * ex_s --
40  *	[line [,line]] s[ubstitute] [[/;]pat[/;]/repl[/;] [cgr] [count] [#lp]]
41  *
42  *	Substitute on lines matching a pattern.
43  *
44  * PUBLIC: int ex_s(SCR *, EXCMD *);
45  */
46 int
47 ex_s(SCR *sp, EXCMD *cmdp)
48 {
49 	regex_t *re;
50 	size_t blen, len;
51 	u_int flags;
52 	int delim;
53 	CHAR_T *bp, *p, *ptrn, *rep, *t;
54 
55 	/*
56 	 * Skip leading white space.
57 	 *
58 	 * !!!
59 	 * Historic vi allowed any non-alphanumeric to serve as the
60 	 * substitution command delimiter.
61 	 *
62 	 * !!!
63 	 * If the arguments are empty, it's the same as &, i.e. we
64 	 * repeat the last substitution.
65 	 */
66 	if (cmdp->argc == 0)
67 		goto subagain;
68 	for (p = cmdp->argv[0]->bp,
69 	    len = cmdp->argv[0]->len; len > 0; --len, ++p) {
70 		if (!cmdskip(*p))
71 			break;
72 	}
73 	if (len == 0)
74 subagain:	return (ex_subagain(sp, cmdp));
75 
76 	delim = *p++;
77 	if (is09azAZ(delim) || delim == '\\')
78 		return (s(sp, cmdp, p, &sp->subre_c, SUB_MUSTSETR));
79 
80 	/*
81 	 * !!!
82 	 * The full-blown substitute command reset the remembered
83 	 * state of the 'c' and 'g' suffices.
84 	 */
85 	sp->c_suffix = sp->g_suffix = 0;
86 
87 	/*
88 	 * Get the pattern string, toss escaping characters.
89 	 *
90 	 * !!!
91 	 * Historic vi accepted any of the following forms:
92 	 *
93 	 *	:s/abc/def/		change "abc" to "def"
94 	 *	:s/abc/def		change "abc" to "def"
95 	 *	:s/abc/			delete "abc"
96 	 *	:s/abc			delete "abc"
97 	 *
98 	 * QUOTING NOTE:
99 	 *
100 	 * Only toss an escaping character if it escapes a delimiter.
101 	 * This means that "s/A/\\\\f" replaces "A" with "\\f".  It
102 	 * would be nice to be more regular, i.e. for each layer of
103 	 * escaping a single escaping character is removed, but that's
104 	 * not how the historic vi worked.
105 	 */
106 	for (ptrn = t = p;;) {
107 		if (p[0] == '\0' || p[0] == delim) {
108 			if (p[0] == delim)
109 				++p;
110 			/*
111 			 * !!!
112 			 * Nul terminate the pattern string -- it's passed
113 			 * to regcomp which doesn't understand anything else.
114 			 */
115 			*t = '\0';
116 			break;
117 		}
118 		if (p[0] == '\\') {
119 			if (p[1] == delim)
120 				++p;
121 			else if (p[1] == '\\')
122 				*t++ = *p++;
123 		}
124 		*t++ = *p++;
125 	}
126 
127 	/*
128 	 * If the pattern string is empty, use the last RE (not just the
129 	 * last substitution RE).
130 	 */
131 	if (*ptrn == '\0') {
132 		if (sp->re == NULL) {
133 			ex_emsg(sp, NULL, EXM_NOPREVRE);
134 			return (1);
135 		}
136 
137 		/* Re-compile the RE if necessary. */
138 		if (!F_ISSET(sp, SC_RE_SEARCH) &&
139 		    re_compile(sp, sp->re, sp->re_len,
140 		    NULL, NULL, &sp->re_c, RE_C_SEARCH))
141 			return (1);
142 		flags = 0;
143 	} else {
144 		/*
145 		 * !!!
146 		 * Compile the RE.  Historic practice is that substitutes set
147 		 * the search direction as well as both substitute and search
148 		 * RE's.  We compile the RE twice, as we don't want to bother
149 		 * ref counting the pattern string and (opaque) structure.
150 		 */
151 		if (re_compile(sp, ptrn, t - ptrn, &sp->re,
152 		    &sp->re_len, &sp->re_c, RE_C_SEARCH))
153 			return (1);
154 		if (re_compile(sp, ptrn, t - ptrn, &sp->subre,
155 		    &sp->subre_len, &sp->subre_c, RE_C_SUBST))
156 			return (1);
157 
158 		flags = SUB_FIRST;
159 		sp->searchdir = FORWARD;
160 	}
161 	re = &sp->re_c;
162 
163 	/*
164 	 * Get the replacement string.
165 	 *
166 	 * The special character & (\& if O_MAGIC not set) matches the
167 	 * entire RE.  No handling of & is required here, it's done by
168 	 * re_sub().
169 	 *
170 	 * The special character ~ (\~ if O_MAGIC not set) inserts the
171 	 * previous replacement string into this replacement string.
172 	 * Count ~'s to figure out how much space we need.  We could
173 	 * special case nonexistent last patterns or whether or not
174 	 * O_MAGIC is set, but it's probably not worth the effort.
175 	 *
176 	 * QUOTING NOTE:
177 	 *
178 	 * Only toss an escaping character if it escapes a delimiter or
179 	 * if O_MAGIC is set and it escapes a tilde.
180 	 *
181 	 * !!!
182 	 * If the entire replacement pattern is "%", then use the last
183 	 * replacement pattern.  This semantic was added to vi in System
184 	 * V and then percolated elsewhere, presumably around the time
185 	 * that it was added to their version of ed(1).
186 	 */
187 	if (p[0] == '\0' || p[0] == delim) {
188 		if (p[0] == delim)
189 			++p;
190 		free(sp->repl);
191 		sp->repl = NULL;
192 		sp->repl_len = 0;
193 	} else if (p[0] == '%' && (p[1] == '\0' || p[1] == delim))
194 		p += p[1] == delim ? 2 : 1;
195 	else {
196 		for (rep = p, len = 0;
197 		    p[0] != '\0' && p[0] != delim; ++p, ++len)
198 			if (p[0] == '~')
199 				len += sp->repl_len;
200 		GET_SPACE_RETW(sp, bp, blen, len);
201 		for (t = bp, len = 0, p = rep;;) {
202 			if (p[0] == '\0' || p[0] == delim) {
203 				if (p[0] == delim)
204 					++p;
205 				break;
206 			}
207 			if (p[0] == '\\') {
208 				if (p[1] == delim)
209 					++p;
210 				else if (p[1] == '\\') {
211 					*t++ = *p++;
212 					++len;
213 				} else if (p[1] == '~') {
214 					++p;
215 					if (!O_ISSET(sp, O_MAGIC))
216 						goto tilde;
217 				}
218 			} else if (p[0] == '~' && O_ISSET(sp, O_MAGIC)) {
219 tilde:				++p;
220 				MEMCPY(t, sp->repl, sp->repl_len);
221 				t += sp->repl_len;
222 				len += sp->repl_len;
223 				continue;
224 			}
225 			*t++ = *p++;
226 			++len;
227 		}
228 		if ((sp->repl_len = len) != 0) {
229 			free(sp->repl);
230 			MALLOC(sp, sp->repl, len * sizeof(CHAR_T));
231 			if (sp->repl == NULL) {
232 				FREE_SPACEW(sp, bp, blen);
233 				return (1);
234 			}
235 			MEMCPY(sp->repl, bp, len);
236 		}
237 		FREE_SPACEW(sp, bp, blen);
238 	}
239 	return (s(sp, cmdp, p, re, flags));
240 }
241 
242 /*
243  * ex_subagain --
244  *	[line [,line]] & [cgr] [count] [#lp]]
245  *
246  *	Substitute using the last substitute RE and replacement pattern.
247  *
248  * PUBLIC: int ex_subagain(SCR *, EXCMD *);
249  */
250 int
251 ex_subagain(SCR *sp, EXCMD *cmdp)
252 {
253 	if (sp->subre == NULL) {
254 		ex_emsg(sp, NULL, EXM_NOPREVRE);
255 		return (1);
256 	}
257 	if (!F_ISSET(sp, SC_RE_SUBST) &&
258 	    re_compile(sp, sp->subre, sp->subre_len,
259 	    NULL, NULL, &sp->subre_c, RE_C_SUBST))
260 		return (1);
261 	return (s(sp,
262 	    cmdp, cmdp->argc ? cmdp->argv[0]->bp : NULL, &sp->subre_c, 0));
263 }
264 
265 /*
266  * ex_subtilde --
267  *	[line [,line]] ~ [cgr] [count] [#lp]]
268  *
269  *	Substitute using the last RE and last substitute replacement pattern.
270  *
271  * PUBLIC: int ex_subtilde(SCR *, EXCMD *);
272  */
273 int
274 ex_subtilde(SCR *sp, EXCMD *cmdp)
275 {
276 	if (sp->re == NULL) {
277 		ex_emsg(sp, NULL, EXM_NOPREVRE);
278 		return (1);
279 	}
280 	if (!F_ISSET(sp, SC_RE_SEARCH) && re_compile(sp, sp->re,
281 	    sp->re_len, NULL, NULL, &sp->re_c, RE_C_SEARCH))
282 		return (1);
283 	return (s(sp,
284 	    cmdp, cmdp->argc ? cmdp->argv[0]->bp : NULL, &sp->re_c, 0));
285 }
286 
287 /*
288  * s --
289  * Do the substitution.  This stuff is *really* tricky.  There are lots of
290  * special cases, and general nastiness.  Don't mess with it unless you're
291  * pretty confident.
292  *
293  * The nasty part of the substitution is what happens when the replacement
294  * string contains newlines.  It's a bit tricky -- consider the information
295  * that has to be retained for "s/f\(o\)o/^M\1^M\1/".  The solution here is
296  * to build a set of newline offsets which we use to break the line up later,
297  * when the replacement is done.  Don't change it unless you're *damned*
298  * confident.
299  */
300 #define	NEEDNEWLINE(sp) do {						\
301 	if (sp->newl_len == sp->newl_cnt) {				\
302 		sp->newl_len += 25;					\
303 		REALLOC(sp, sp->newl, size_t *,				\
304 		    sp->newl_len * sizeof(size_t));			\
305 		if (sp->newl == NULL) {					\
306 			sp->newl_len = 0;				\
307 			return (1);					\
308 		}							\
309 	}								\
310 } while (0)
311 
312 #define	BUILD(sp, l, len) do {						\
313 	if (lbclen + (len) > lblen) {					\
314 		lblen = p2roundup(MAX(lbclen + (len), 256));		\
315 		REALLOC(sp, lb, CHAR_T *, lblen * sizeof(CHAR_T));	\
316 		if (lb == NULL) {					\
317 			lbclen = 0;					\
318 			return (1);					\
319 		}							\
320 	}								\
321 	MEMCPY(lb + lbclen, l, len);					\
322 	lbclen += len;							\
323 } while (0)
324 
325 #define	NEEDSP(sp, len, pnt) do {					\
326 	if (lbclen + (len) > lblen) {					\
327 		lblen = p2roundup(MAX(lbclen + (len), 256));		\
328 		REALLOC(sp, lb, CHAR_T *, lblen * sizeof(CHAR_T));	\
329 		if (lb == NULL) {					\
330 			lbclen = 0;					\
331 			return (1);					\
332 		}							\
333 		pnt = lb + lbclen;					\
334 	}								\
335 } while (0)
336 
337 static int
338 s(SCR *sp, EXCMD *cmdp, CHAR_T *s, regex_t *re, u_int flags)
339 {
340 	EVENT ev;
341 	MARK from, to;
342 	TEXTH tiq[] = {{ 0 }};
343 	recno_t elno, lno, slno;
344 	u_long ul;
345 	regmatch_t match[10];
346 	size_t blen, cnt, last, lbclen, lblen, len, llen;
347 	size_t offset, saved_offset, scno;
348 	int cflag, lflag, nflag, pflag, rflag;
349 	int didsub, do_eol_match, eflags, empty_ok, eval;
350 	int linechanged, matched, quit, rval;
351 	CHAR_T *bp, *lb;
352 	enum nresult nret;
353 
354 	NEEDFILE(sp, cmdp);
355 
356 	slno = sp->lno;
357 	scno = sp->cno;
358 
359 	/*
360 	 * !!!
361 	 * Historically, the 'g' and 'c' suffices were always toggled as flags,
362 	 * so ":s/A/B/" was the same as ":s/A/B/ccgg".  If O_EDCOMPATIBLE was
363 	 * not set, they were initialized to 0 for all substitute commands.  If
364 	 * O_EDCOMPATIBLE was set, they were initialized to 0 only if the user
365 	 * specified substitute/replacement patterns (see ex_s()).
366 	 */
367 	if (!O_ISSET(sp, O_EDCOMPATIBLE))
368 		sp->c_suffix = sp->g_suffix = 0;
369 
370 	/*
371 	 * Historic vi permitted the '#', 'l' and 'p' options in vi mode, but
372 	 * it only displayed the last change.  I'd disallow them, but they are
373 	 * useful in combination with the [v]global commands.  In the current
374 	 * model the problem is combining them with the 'c' flag -- the screen
375 	 * would have to flip back and forth between the confirm screen and the
376 	 * ex print screen, which would be pretty awful.  We do display all
377 	 * changes, though, for what that's worth.
378 	 *
379 	 * !!!
380 	 * Historic vi was fairly strict about the order of "options", the
381 	 * count, and "flags".  I'm somewhat fuzzy on the difference between
382 	 * options and flags, anyway, so this is a simpler approach, and we
383 	 * just take it them in whatever order the user gives them.  (The ex
384 	 * usage statement doesn't reflect this.)
385 	 */
386 	cflag = lflag = nflag = pflag = rflag = 0;
387 	if (s == NULL)
388 		goto noargs;
389 	for (lno = OOBLNO; *s != '\0'; ++s)
390 		switch (*s) {
391 		case ' ':
392 		case '\t':
393 			continue;
394 		case '+':
395 			++cmdp->flagoff;
396 			break;
397 		case '-':
398 			--cmdp->flagoff;
399 			break;
400 		case '0': case '1': case '2': case '3': case '4':
401 		case '5': case '6': case '7': case '8': case '9':
402 			if (lno != OOBLNO)
403 				goto usage;
404 			errno = 0;
405 			nret = nget_uslong(&ul, s, &s, 10);
406 			lno = ul;
407 			if (*s == '\0')		/* Loop increment correction. */
408 				--s;
409 			if (nret != NUM_OK) {
410 				if (nret == NUM_OVER)
411 					msgq(sp, M_ERR, "153|Count overflow");
412 				else if (nret == NUM_UNDER)
413 					msgq(sp, M_ERR, "154|Count underflow");
414 				else
415 					msgq(sp, M_SYSERR, NULL);
416 				return (1);
417 			}
418 			/*
419 			 * In historic vi, the count was inclusive from the
420 			 * second address.
421 			 */
422 			cmdp->addr1.lno = cmdp->addr2.lno;
423 			cmdp->addr2.lno += lno - 1;
424 			if (!db_exist(sp, cmdp->addr2.lno) &&
425 			    db_last(sp, &cmdp->addr2.lno))
426 				return (1);
427 			break;
428 		case '#':
429 			nflag = 1;
430 			break;
431 		case 'c':
432 			sp->c_suffix = !sp->c_suffix;
433 
434 			/* Ex text structure initialization. */
435 			if (F_ISSET(sp, SC_EX))
436 				TAILQ_INIT(tiq);
437 			break;
438 		case 'g':
439 			sp->g_suffix = !sp->g_suffix;
440 			break;
441 		case 'l':
442 			lflag = 1;
443 			break;
444 		case 'p':
445 			pflag = 1;
446 			break;
447 		case 'r':
448 			if (LF_ISSET(SUB_FIRST)) {
449 				msgq(sp, M_ERR,
450 		    "155|Regular expression specified; r flag meaningless");
451 				return (1);
452 			}
453 			if (!F_ISSET(sp, SC_RE_SEARCH)) {
454 				ex_emsg(sp, NULL, EXM_NOPREVRE);
455 				return (1);
456 			}
457 			rflag = 1;
458 			re = &sp->re_c;
459 			break;
460 		default:
461 			goto usage;
462 		}
463 
464 	if (*s != '\0' || (!rflag && LF_ISSET(SUB_MUSTSETR))) {
465 usage:		ex_emsg(sp, cmdp->cmd->usage, EXM_USAGE);
466 		return (1);
467 	}
468 
469 noargs:	if (F_ISSET(sp, SC_VI) && sp->c_suffix && (lflag || nflag || pflag)) {
470 		msgq(sp, M_ERR,
471 "156|The #, l and p flags may not be combined with the c flag in vi mode");
472 		return (1);
473 	}
474 
475 	/*
476 	 * bp:		if interactive, line cache
477 	 * blen:	if interactive, line cache length
478 	 * lb:		build buffer pointer.
479 	 * lbclen:	current length of built buffer.
480 	 * lblen;	length of build buffer.
481 	 */
482 	bp = lb = NULL;
483 	blen = lbclen = lblen = 0;
484 
485 	/* For each line... */
486 	lno = cmdp->addr1.lno == 0 ? 1 : cmdp->addr1.lno;
487 	for (matched = quit = 0,
488 	    elno = cmdp->addr2.lno; !quit && lno <= elno; ++lno) {
489 
490 		/* Someone's unhappy, time to stop. */
491 		if (INTERRUPTED(sp))
492 			break;
493 
494 		/* Get the line. */
495 		if (db_get(sp, lno, DBG_FATAL, &s, &llen))
496 			goto err;
497 
498 		/*
499 		 * Make a local copy if doing confirmation -- when calling
500 		 * the confirm routine we're likely to lose the cached copy.
501 		 */
502 		if (sp->c_suffix) {
503 			if (bp == NULL) {
504 				GET_SPACE_RETW(sp, bp, blen, llen);
505 			} else
506 				ADD_SPACE_RETW(sp, bp, blen, llen);
507 			MEMCPY(bp, s, llen);
508 			s = bp;
509 		}
510 
511 		/* Start searching from the beginning. */
512 		offset = 0;
513 		len = llen;
514 
515 		/* Reset the build buffer offset. */
516 		lbclen = 0;
517 
518 		/* Reset empty match flag. */
519 		empty_ok = 1;
520 
521 		/*
522 		 * We don't want to have to do a setline if the line didn't
523 		 * change -- keep track of whether or not this line changed.
524 		 * If doing confirmations, don't want to keep setting the
525 		 * line if change is refused -- keep track of substitutions.
526 		 */
527 		didsub = linechanged = 0;
528 
529 		/* New line, do an EOL match. */
530 		do_eol_match = 1;
531 
532 		/* It's not nul terminated, but we pretend it is. */
533 		eflags = REG_STARTEND;
534 
535 		/*
536 		 * The search area is from s + offset to the EOL.
537 		 *
538 		 * Generally, match[0].rm_so is the offset of the start
539 		 * of the match from the start of the search, and offset
540 		 * is the offset of the start of the last search.
541 		 */
542 nextmatch:	match[0].rm_so = 0;
543 		match[0].rm_eo = len;
544 
545 		/* Get the next match. */
546 		eval = regexec(re, s + offset, 10, match, eflags);
547 
548 		/*
549 		 * There wasn't a match or if there was an error, deal with
550 		 * it.  If there was a previous match in this line, resolve
551 		 * the changes into the database.  Otherwise, just move on.
552 		 */
553 		if (eval == REG_NOMATCH)
554 			goto endmatch;
555 		if (eval != 0) {
556 			re_error(sp, eval, re);
557 			goto err;
558 		}
559 		matched = 1;
560 
561 		/* Only the first search can match an anchored expression. */
562 		eflags |= REG_NOTBOL;
563 
564 		/*
565 		 * !!!
566 		 * It's possible to match 0-length strings -- for example, the
567 		 * command s;a*;X;, when matched against the string "aabb" will
568 		 * result in "XbXbX", i.e. the matches are "aa", the space
569 		 * between the b's and the space between the b's and the end of
570 		 * the string.  There is a similar space between the beginning
571 		 * of the string and the a's.  The rule that we use (because vi
572 		 * historically used it) is that any 0-length match, occurring
573 		 * immediately after a match, is ignored.  Otherwise, the above
574 		 * example would have resulted in "XXbXbX".  Another example is
575 		 * incorrectly using " *" to replace groups of spaces with one
576 		 * space.
577 		 *
578 		 * The way we do this is that if we just had a successful match,
579 		 * the starting offset does not skip characters, and the match
580 		 * is empty, ignore the match and move forward.  If there's no
581 		 * more characters in the string, we were attempting to match
582 		 * after the last character, so quit.
583 		 */
584 		if (!empty_ok && match[0].rm_so == 0 && match[0].rm_eo == 0) {
585 			empty_ok = 1;
586 			if (len == 0)
587 				goto endmatch;
588 			BUILD(sp, s + offset, 1);
589 			++offset;
590 			--len;
591 			goto nextmatch;
592 		}
593 
594 		/* Confirm change. */
595 		if (sp->c_suffix) {
596 			/*
597 			 * Set the cursor position for confirmation.  Note,
598 			 * if we matched on a '$', the cursor may be past
599 			 * the end of line.
600 			 */
601 			from.lno = to.lno = lno;
602 			from.cno = match[0].rm_so + offset;
603 			to.cno = match[0].rm_eo + offset;
604 			/*
605 			 * Both ex and vi have to correct for a change before
606 			 * the first character in the line.
607 			 */
608 			if (llen == 0)
609 				from.cno = to.cno = 0;
610 			if (F_ISSET(sp, SC_VI)) {
611 				/*
612 				 * Only vi has to correct for a change after
613 				 * the last character in the line.
614 				 *
615 				 * XXX
616 				 * It would be nice to change the vi code so
617 				 * that we could display a cursor past EOL.
618 				 */
619 				if (to.cno >= llen)
620 					to.cno = llen - 1;
621 				if (from.cno >= llen)
622 					from.cno = llen - 1;
623 
624 				sp->lno = from.lno;
625 				sp->cno = from.cno;
626 				if (vs_refresh(sp, 1))
627 					goto err;
628 
629 				vs_update(sp, msg_cat(sp,
630 				    "169|Confirm change? [n]", NULL), NULL);
631 
632 				if (v_event_get(sp, &ev, 0, 0))
633 					goto err;
634 				switch (ev.e_event) {
635 				case E_CHARACTER:
636 					break;
637 				case E_EOF:
638 				case E_ERR:
639 				case E_INTERRUPT:
640 					goto lquit;
641 				default:
642 					v_event_err(sp, &ev);
643 					goto lquit;
644 				}
645 			} else {
646 				if (ex_print(sp, cmdp, &from, &to, 0) ||
647 				    ex_scprint(sp, &from, &to))
648 					goto lquit;
649 				if (ex_txt(sp, tiq, 0, TXT_CR))
650 					goto err;
651 				ev.e_c = TAILQ_FIRST(tiq)->lb[0];
652 			}
653 
654 			switch (ev.e_c) {
655 			case CH_YES:
656 				break;
657 			default:
658 			case CH_NO:
659 				didsub = 0;
660 				BUILD(sp, s +offset, match[0].rm_eo);
661 				goto skip;
662 			case CH_QUIT:
663 				/* Set the quit/interrupted flags. */
664 lquit:				quit = 1;
665 				F_SET(sp->gp, G_INTERRUPTED);
666 
667 				/*
668 				 * Resolve any changes, then return to (and
669 				 * exit from) the main loop.
670 				 */
671 				goto endmatch;
672 			}
673 		}
674 
675 		/*
676 		 * Set the cursor to the last position changed, converting
677 		 * from 1-based to 0-based.
678 		 */
679 		sp->lno = lno;
680 		sp->cno = match[0].rm_so;
681 
682 		/* Copy the bytes before the match into the build buffer. */
683 		BUILD(sp, s + offset, match[0].rm_so);
684 
685 		/* Substitute the matching bytes. */
686 		didsub = 1;
687 		if (re_sub(sp, s + offset, &lb, &lbclen, &lblen, match))
688 			goto err;
689 
690 		/* Set the change flag so we know this line was modified. */
691 		linechanged = 1;
692 
693 		/* Move past the matched bytes. */
694 skip:		offset += match[0].rm_eo;
695 		len -= match[0].rm_eo;
696 
697 		/* A match cannot be followed by an empty pattern. */
698 		empty_ok = 0;
699 
700 		/*
701 		 * If doing a global change with confirmation, we have to
702 		 * update the screen.  The basic idea is to store the line
703 		 * so the screen update routines can find it, and restart.
704 		 */
705 		if (didsub && sp->c_suffix && sp->g_suffix) {
706 			/*
707 			 * The new search offset will be the end of the
708 			 * modified line.
709 			 */
710 			saved_offset = lbclen;
711 
712 			/* Copy the rest of the line. */
713 			if (len)
714 				BUILD(sp, s + offset, len);
715 
716 			/* Set the new offset. */
717 			offset = saved_offset;
718 
719 			/* Store inserted lines, adjusting the build buffer. */
720 			last = 0;
721 			if (sp->newl_cnt) {
722 				for (cnt = 0;
723 				    cnt < sp->newl_cnt; ++cnt, ++lno, ++elno) {
724 					if (db_insert(sp, lno,
725 					    lb + last, sp->newl[cnt] - last))
726 						goto err;
727 					last = sp->newl[cnt] + 1;
728 					++sp->rptlines[L_ADDED];
729 				}
730 				lbclen -= last;
731 				offset -= last;
732 				sp->newl_cnt = 0;
733 			}
734 
735 			/* Store and retrieve the line. */
736 			if (db_set(sp, lno, lb + last, lbclen))
737 				goto err;
738 			if (db_get(sp, lno, DBG_FATAL, &s, &llen))
739 				goto err;
740 			ADD_SPACE_RETW(sp, bp, blen, llen);
741 			MEMCPY(bp, s, llen);
742 			s = bp;
743 			len = llen - offset;
744 
745 			/* Restart the build. */
746 			lbclen = 0;
747 			BUILD(sp, s, offset);
748 
749 			/*
750 			 * If we haven't already done the after-the-string
751 			 * match, do one.  Set REG_NOTEOL so the '$' pattern
752 			 * only matches once.
753 			 */
754 			if (!do_eol_match)
755 				goto endmatch;
756 			if (offset == len) {
757 				do_eol_match = 0;
758 				eflags |= REG_NOTEOL;
759 			}
760 			goto nextmatch;
761 		}
762 
763 		/*
764 		 * If it's a global:
765 		 *
766 		 * If at the end of the string, do a test for the after
767 		 * the string match.  Set REG_NOTEOL so the '$' pattern
768 		 * only matches once.
769 		 */
770 		if (sp->g_suffix && do_eol_match) {
771 			if (len == 0) {
772 				do_eol_match = 0;
773 				eflags |= REG_NOTEOL;
774 			}
775 			goto nextmatch;
776 		}
777 
778 endmatch:	if (!linechanged)
779 			continue;
780 
781 		/* Copy any remaining bytes into the build buffer. */
782 		if (len)
783 			BUILD(sp, s + offset, len);
784 
785 		/* Store inserted lines, adjusting the build buffer. */
786 		last = 0;
787 		if (sp->newl_cnt) {
788 			for (cnt = 0;
789 			    cnt < sp->newl_cnt; ++cnt, ++lno, ++elno) {
790 				if (db_insert(sp,
791 				    lno, lb + last, sp->newl[cnt] - last))
792 					goto err;
793 				last = sp->newl[cnt] + 1;
794 				++sp->rptlines[L_ADDED];
795 			}
796 			lbclen -= last;
797 			sp->newl_cnt = 0;
798 		}
799 
800 		/* Store the changed line. */
801 		if (db_set(sp, lno, lb + last, lbclen))
802 			goto err;
803 
804 		/* Update changed line counter. */
805 		if (sp->rptlchange != lno) {
806 			sp->rptlchange = lno;
807 			++sp->rptlines[L_CHANGED];
808 		}
809 
810 		/*
811 		 * !!!
812 		 * Display as necessary.  Historic practice is to only
813 		 * display the last line of a line split into multiple
814 		 * lines.
815 		 */
816 		if (lflag || nflag || pflag) {
817 			from.lno = to.lno = lno;
818 			from.cno = to.cno = 0;
819 			if (lflag)
820 				(void)ex_print(sp, cmdp, &from, &to, E_C_LIST);
821 			if (nflag)
822 				(void)ex_print(sp, cmdp, &from, &to, E_C_HASH);
823 			if (pflag)
824 				(void)ex_print(sp, cmdp, &from, &to, E_C_PRINT);
825 		}
826 	}
827 
828 	/*
829 	 * !!!
830 	 * Historically, vi attempted to leave the cursor at the same place if
831 	 * the substitution was done at the current cursor position.  Otherwise
832 	 * it moved it to the first non-blank of the last line changed.  There
833 	 * were some problems: for example, :s/$/foo/ with the cursor on the
834 	 * last character of the line left the cursor on the last character, or
835 	 * the & command with multiple occurrences of the matching string in the
836 	 * line usually left the cursor in a fairly random position.
837 	 *
838 	 * We try to do the same thing, with the exception that if the user is
839 	 * doing substitution with confirmation, we move to the last line about
840 	 * which the user was consulted, as opposed to the last line that they
841 	 * actually changed.  This prevents a screen flash if the user doesn't
842 	 * change many of the possible lines.
843 	 */
844 	if (!sp->c_suffix && (sp->lno != slno || sp->cno != scno)) {
845 		sp->cno = 0;
846 		(void)nonblank(sp, sp->lno, &sp->cno);
847 	}
848 
849 	/*
850 	 * If not in a global command, and nothing matched, say so.
851 	 * Else, if none of the lines displayed, put something up.
852 	 */
853 	rval = 0;
854 	if (!matched) {
855 		if (!F_ISSET(sp, SC_EX_GLOBAL)) {
856 			msgq(sp, M_ERR, "157|No match found");
857 			goto err;
858 		}
859 	} else if (!lflag && !nflag && !pflag)
860 		F_SET(cmdp, E_AUTOPRINT);
861 
862 	if (0) {
863 err:		rval = 1;
864 	}
865 
866 	if (bp != NULL)
867 		FREE_SPACEW(sp, bp, blen);
868 	free(lb);
869 	return (rval);
870 }
871 
872 /*
873  * re_compile --
874  *	Compile the RE.
875  *
876  * PUBLIC: int re_compile(SCR *,
877  * PUBLIC:     CHAR_T *, size_t, CHAR_T **, size_t *, regex_t *, u_int);
878  */
879 int
880 re_compile(SCR *sp, CHAR_T *ptrn, size_t plen, CHAR_T **ptrnp, size_t *lenp, regex_t *rep, u_int flags)
881 {
882 	size_t len;
883 	int reflags, replaced, rval;
884 	CHAR_T *p;
885 
886 	/* Set RE flags. */
887 	reflags = 0;
888 	if (!LF_ISSET(RE_C_CSCOPE | RE_C_TAG)) {
889 		if (O_ISSET(sp, O_EXTENDED))
890 			reflags |= REG_EXTENDED;
891 		if (O_ISSET(sp, O_IGNORECASE))
892 			reflags |= REG_ICASE;
893 		if (O_ISSET(sp, O_ICLOWER)) {
894 			for (p = ptrn, len = plen; len > 0; ++p, --len)
895 				if (ISUPPER(*p))
896 					break;
897 			if (len == 0)
898 				reflags |= REG_ICASE;
899 		}
900 	}
901 
902 	/* If we're replacing a saved value, clear the old one. */
903 	if (LF_ISSET(RE_C_SEARCH) && F_ISSET(sp, SC_RE_SEARCH)) {
904 		regfree(&sp->re_c);
905 		F_CLR(sp, SC_RE_SEARCH);
906 	}
907 	if (LF_ISSET(RE_C_SUBST) && F_ISSET(sp, SC_RE_SUBST)) {
908 		regfree(&sp->subre_c);
909 		F_CLR(sp, SC_RE_SUBST);
910 	}
911 
912 	/*
913 	 * If we're saving the string, it's a pattern we haven't seen before,
914 	 * so convert the vi-style RE's to POSIX 1003.2 RE's.  Save a copy for
915 	 * later recompilation.   Free any previously saved value.
916 	 */
917 	if (ptrnp != NULL) {
918 		replaced = 0;
919 		if (LF_ISSET(RE_C_CSCOPE)) {
920 			if (re_cscope_conv(sp, &ptrn, &plen, &replaced))
921 				return (1);
922 			/*
923 			 * XXX
924 			 * Currently, the match-any-<blank> expression used in
925 			 * re_cscope_conv() requires extended RE's.  This may
926 			 * not be right or safe.
927 			 */
928 			reflags |= REG_EXTENDED;
929 		} else if (LF_ISSET(RE_C_TAG)) {
930 			if (re_tag_conv(sp, &ptrn, &plen, &replaced))
931 				return (1);
932 		} else
933 			if (re_conv(sp, &ptrn, &plen, &replaced))
934 				return (1);
935 
936 		/* Discard previous pattern. */
937 		free(*ptrnp);
938 		*ptrnp = NULL;
939 
940 		if (lenp != NULL)
941 			*lenp = plen;
942 
943 		/*
944 		 * Copy the string into allocated memory.
945 		 *
946 		 * XXX
947 		 * Regcomp isn't 8-bit clean, so the pattern is nul-terminated
948 		 * for now.  There's just no other solution.
949 		 */
950 		MALLOC(sp, *ptrnp, (plen + 1) * sizeof(CHAR_T));
951 		if (*ptrnp != NULL) {
952 			MEMCPY(*ptrnp, ptrn, plen);
953 			(*ptrnp)[plen] = '\0';
954 		}
955 
956 		/* Free up conversion-routine-allocated memory. */
957 		if (replaced)
958 			FREE_SPACEW(sp, ptrn, 0);
959 
960 		if (*ptrnp == NULL)
961 			return (1);
962 
963 		ptrn = *ptrnp;
964 	}
965 
966 	/*
967 	 * XXX
968 	 * Regcomp isn't 8-bit clean, so we just lost if the pattern
969 	 * contained a nul.  Bummer!
970 	 */
971 	if ((rval = regcomp(rep, ptrn, /* plen, */ reflags)) != 0) {
972 		if (!LF_ISSET(RE_C_SILENT))
973 			re_error(sp, rval, rep);
974 		return (1);
975 	}
976 
977 	if (LF_ISSET(RE_C_SEARCH))
978 		F_SET(sp, SC_RE_SEARCH);
979 	if (LF_ISSET(RE_C_SUBST))
980 		F_SET(sp, SC_RE_SUBST);
981 
982 	return (0);
983 }
984 
985 /*
986  * re_conv --
987  *	Convert vi's regular expressions into something that the
988  *	the POSIX 1003.2 RE functions can handle.
989  *
990  * There are three conversions we make to make vi's RE's (specifically
991  * the global, search, and substitute patterns) work with POSIX RE's.
992  *
993  * 1: If O_MAGIC is not set, strip backslashes from the magic character
994  *    set (.[*~) that have them, and add them to the ones that don't.
995  * 2: If O_MAGIC is not set, the string "\~" is replaced with the text
996  *    from the last substitute command's replacement string.  If O_MAGIC
997  *    is set, it's the string "~".
998  * 3: The pattern \<ptrn\> does "word" searches, convert it to use the
999  *    new RE escapes.
1000  *
1001  * !!!/XXX
1002  * This doesn't exactly match the historic behavior of vi because we do
1003  * the ~ substitution before calling the RE engine, so magic characters
1004  * in the replacement string will be expanded by the RE engine, and they
1005  * weren't historically.  It's a bug.
1006  */
1007 static int
1008 re_conv(SCR *sp, CHAR_T **ptrnp, size_t *plenp, int *replacedp)
1009 {
1010 	size_t blen, len, needlen;
1011 	int magic;
1012 	CHAR_T *bp, *p, *t;
1013 
1014 	/*
1015 	 * First pass through, we figure out how much space we'll need.
1016 	 * We do it in two passes, on the grounds that most of the time
1017 	 * the user is doing a search and won't have magic characters.
1018 	 * That way we can skip most of the memory allocation and copies.
1019 	 */
1020 	magic = 0;
1021 	for (p = *ptrnp, len = *plenp, needlen = 0; len > 0; ++p, --len)
1022 		switch (*p) {
1023 		case '\\':
1024 			if (len > 1) {
1025 				--len;
1026 				switch (*++p) {
1027 				case '<':
1028 					magic = 1;
1029 					needlen += RE_WSTART_LEN + 1;
1030 					break;
1031 				case '>':
1032 					magic = 1;
1033 					needlen += RE_WSTOP_LEN + 1;
1034 					break;
1035 				case '~':
1036 					if (!O_ISSET(sp, O_MAGIC)) {
1037 						magic = 1;
1038 						needlen += sp->repl_len;
1039 					}
1040 					break;
1041 				case '.':
1042 				case '[':
1043 				case '*':
1044 					if (!O_ISSET(sp, O_MAGIC)) {
1045 						magic = 1;
1046 						needlen += 1;
1047 					}
1048 					break;
1049 				default:
1050 					needlen += 2;
1051 				}
1052 			} else
1053 				needlen += 1;
1054 			break;
1055 		case '~':
1056 			if (O_ISSET(sp, O_MAGIC)) {
1057 				magic = 1;
1058 				needlen += sp->repl_len;
1059 			}
1060 			break;
1061 		case '.':
1062 		case '[':
1063 		case '*':
1064 			if (!O_ISSET(sp, O_MAGIC)) {
1065 				magic = 1;
1066 				needlen += 2;
1067 			}
1068 			break;
1069 		default:
1070 			needlen += 1;
1071 			break;
1072 		}
1073 
1074 	if (!magic) {
1075 		*replacedp = 0;
1076 		return (0);
1077 	}
1078 
1079 	/* Get enough memory to hold the final pattern. */
1080 	*replacedp = 1;
1081 	GET_SPACE_RETW(sp, bp, blen, needlen);
1082 
1083 	for (p = *ptrnp, len = *plenp, t = bp; len > 0; ++p, --len)
1084 		switch (*p) {
1085 		case '\\':
1086 			if (len > 1) {
1087 				--len;
1088 				switch (*++p) {
1089 				case '<':
1090 					MEMCPY(t,
1091 					    RE_WSTART, RE_WSTART_LEN);
1092 					t += RE_WSTART_LEN;
1093 					break;
1094 				case '>':
1095 					MEMCPY(t,
1096 					    RE_WSTOP, RE_WSTOP_LEN);
1097 					t += RE_WSTOP_LEN;
1098 					break;
1099 				case '~':
1100 					if (O_ISSET(sp, O_MAGIC))
1101 						*t++ = '~';
1102 					else {
1103 						MEMCPY(t,
1104 						    sp->repl, sp->repl_len);
1105 						t += sp->repl_len;
1106 					}
1107 					break;
1108 				case '.':
1109 				case '[':
1110 				case '*':
1111 					if (O_ISSET(sp, O_MAGIC))
1112 						*t++ = '\\';
1113 					*t++ = *p;
1114 					break;
1115 				default:
1116 					*t++ = '\\';
1117 					*t++ = *p;
1118 				}
1119 			} else
1120 				*t++ = '\\';
1121 			break;
1122 		case '~':
1123 			if (O_ISSET(sp, O_MAGIC)) {
1124 				MEMCPY(t, sp->repl, sp->repl_len);
1125 				t += sp->repl_len;
1126 			} else
1127 				*t++ = '~';
1128 			break;
1129 		case '.':
1130 		case '[':
1131 		case '*':
1132 			if (!O_ISSET(sp, O_MAGIC))
1133 				*t++ = '\\';
1134 			*t++ = *p;
1135 			break;
1136 		default:
1137 			*t++ = *p;
1138 			break;
1139 		}
1140 
1141 	*ptrnp = bp;
1142 	*plenp = t - bp;
1143 	return (0);
1144 }
1145 
1146 /*
1147  * re_tag_conv --
1148  *	Convert a tags search path into something that the POSIX
1149  *	1003.2 RE functions can handle.
1150  */
1151 static int
1152 re_tag_conv(SCR *sp, CHAR_T **ptrnp, size_t *plenp, int *replacedp)
1153 {
1154 	size_t blen, len;
1155 	int lastdollar;
1156 	CHAR_T *bp, *p, *t;
1157 
1158 	len = *plenp;
1159 
1160 	/* Max memory usage is 2 times the length of the string. */
1161 	*replacedp = 1;
1162 	GET_SPACE_RETW(sp, bp, blen, len * 2);
1163 
1164 	p = *ptrnp;
1165 	t = bp;
1166 
1167 	/* If the last character is a '/' or '?', we just strip it. */
1168 	if (len > 0 && (p[len - 1] == '/' || p[len - 1] == '?'))
1169 		--len;
1170 
1171 	/* If the next-to-last or last character is a '$', it's magic. */
1172 	if (len > 0 && p[len - 1] == '$') {
1173 		--len;
1174 		lastdollar = 1;
1175 	} else
1176 		lastdollar = 0;
1177 
1178 	/* If the first character is a '/' or '?', we just strip it. */
1179 	if (len > 0 && (p[0] == '/' || p[0] == '?')) {
1180 		++p;
1181 		--len;
1182 	}
1183 
1184 	/* If the first or second character is a '^', it's magic. */
1185 	if (p[0] == '^') {
1186 		*t++ = *p++;
1187 		--len;
1188 	}
1189 
1190 	/*
1191 	 * Escape every other magic character we can find, meanwhile stripping
1192 	 * the backslashes ctags inserts when escaping the search delimiter
1193 	 * characters.
1194 	 */
1195 	for (; len > 0; --len) {
1196 		if (p[0] == '\\' && (p[1] == '/' || p[1] == '?')) {
1197 			++p;
1198 			--len;
1199 		} else if (STRCHR(L("^.[]$*"), p[0]))
1200 			*t++ = '\\';
1201 		*t++ = *p++;
1202 	}
1203 	if (lastdollar)
1204 		*t++ = '$';
1205 
1206 	*ptrnp = bp;
1207 	*plenp = t - bp;
1208 	return (0);
1209 }
1210 
1211 /*
1212  * re_cscope_conv --
1213  *	 Convert a cscope search path into something that the POSIX
1214  *      1003.2 RE functions can handle.
1215  */
1216 static int
1217 re_cscope_conv(SCR *sp, CHAR_T **ptrnp, size_t *plenp, int *replacedp)
1218 {
1219 	size_t blen, len, nspaces;
1220 	CHAR_T *bp, *t;
1221 	CHAR_T *p;
1222 	CHAR_T *wp;
1223 	size_t wlen;
1224 
1225 	/*
1226 	 * Each space in the source line printed by cscope represents an
1227 	 * arbitrary sequence of spaces, tabs, and comments.
1228 	 */
1229 #define	CSCOPE_RE_SPACE		"([ \t]|/\\*([^*]|\\*/)*\\*/)*"
1230 #define CSCOPE_LEN	sizeof(CSCOPE_RE_SPACE) - 1
1231 	CHAR2INT(sp, CSCOPE_RE_SPACE, CSCOPE_LEN, wp, wlen);
1232 	for (nspaces = 0, p = *ptrnp, len = *plenp; len > 0; ++p, --len)
1233 		if (*p == ' ')
1234 			++nspaces;
1235 
1236 	/*
1237 	 * Allocate plenty of space:
1238 	 *	the string, plus potential escaping characters;
1239 	 *	nspaces + 2 copies of CSCOPE_RE_SPACE;
1240 	 *	^, $, nul terminator characters.
1241 	 */
1242 	*replacedp = 1;
1243 	len = (p - *ptrnp) * 2 + (nspaces + 2) * sizeof(CSCOPE_RE_SPACE) + 3;
1244 	GET_SPACE_RETW(sp, bp, blen, len);
1245 
1246 	p = *ptrnp;
1247 	t = bp;
1248 
1249 	*t++ = '^';
1250 	MEMCPY(t, wp, wlen);
1251 	t += wlen;
1252 
1253 	for (len = *plenp; len > 0; ++p, --len)
1254 		if (*p == ' ') {
1255 			MEMCPY(t, wp, wlen);
1256 			t += wlen;
1257 		} else {
1258 			if (STRCHR(L("\\^.[]$*+?()|{}"), *p))
1259 				*t++ = '\\';
1260 			*t++ = *p;
1261 		}
1262 
1263 	MEMCPY(t, wp, wlen);
1264 	t += wlen;
1265 	*t++ = '$';
1266 
1267 	*ptrnp = bp;
1268 	*plenp = t - bp;
1269 	return (0);
1270 }
1271 
1272 /*
1273  * re_error --
1274  *	Report a regular expression error.
1275  *
1276  * PUBLIC: void re_error(SCR *, int, regex_t *);
1277  */
1278 void
1279 re_error(SCR *sp, int errcode, regex_t *preg)
1280 {
1281 	size_t s;
1282 	char *oe;
1283 
1284 	s = regerror(errcode, preg, "", 0);
1285 	MALLOC(sp, oe, s);
1286 	if (oe != NULL) {
1287 		(void)regerror(errcode, preg, oe, s);
1288 		msgq(sp, M_ERR, "RE error: %s", oe);
1289 		free(oe);
1290 	}
1291 }
1292 
1293 /*
1294  * re_sub --
1295  * 	Do the substitution for a regular expression.
1296  */
1297 static int
1298 re_sub(
1299 	SCR *sp,
1300 	CHAR_T *ip,			/* Input line. */
1301 	CHAR_T **lbp,
1302 	size_t *lbclenp,
1303 	size_t *lblenp,
1304 	regmatch_t match[10])
1305 {
1306 	enum { C_NOTSET, C_LOWER, C_ONELOWER, C_ONEUPPER, C_UPPER } conv;
1307 	size_t lbclen, lblen;		/* Local copies. */
1308 	size_t mlen;			/* Match length. */
1309 	size_t rpl;			/* Remaining replacement length. */
1310 	CHAR_T *rp;			/* Replacement pointer. */
1311 	int ch;
1312 	int no;				/* Match replacement offset. */
1313 	CHAR_T *p, *t;			/* Buffer pointers. */
1314 	CHAR_T *lb;			/* Local copies. */
1315 
1316 	lb = *lbp;			/* Get local copies. */
1317 	lbclen = *lbclenp;
1318 	lblen = *lblenp;
1319 
1320 	/*
1321 	 * QUOTING NOTE:
1322 	 *
1323 	 * There are some special sequences that vi provides in the
1324 	 * replacement patterns.
1325 	 *	 & string the RE matched (\& if nomagic set)
1326 	 *	\# n-th regular subexpression
1327 	 *	\E end \U, \L conversion
1328 	 *	\e end \U, \L conversion
1329 	 *	\l convert the next character to lower-case
1330 	 *	\L convert to lower-case, until \E, \e, or end of replacement
1331 	 *	\u convert the next character to upper-case
1332 	 *	\U convert to upper-case, until \E, \e, or end of replacement
1333 	 *
1334 	 * Otherwise, since this is the lowest level of replacement, discard
1335 	 * all escaping characters.  This (hopefully) matches historic practice.
1336 	 */
1337 #define	OUTCH(ch, nltrans) do {						\
1338 	ARG_CHAR_T __ch = (ch);						\
1339 	e_key_t __value = KEY_VAL(sp, __ch);				\
1340 	if (nltrans && (__value == K_CR || __value == K_NL)) {		\
1341 		NEEDNEWLINE(sp);					\
1342 		sp->newl[sp->newl_cnt++] = lbclen;			\
1343 	} else if (conv != C_NOTSET) {					\
1344 		switch (conv) {						\
1345 		case C_ONELOWER:					\
1346 			conv = C_NOTSET;				\
1347 			/* FALLTHROUGH */				\
1348 		case C_LOWER:						\
1349 			if (ISUPPER(__ch))				\
1350 				__ch = TOLOWER(__ch);			\
1351 			break;						\
1352 		case C_ONEUPPER:					\
1353 			conv = C_NOTSET;				\
1354 			/* FALLTHROUGH */				\
1355 		case C_UPPER:						\
1356 			if (ISLOWER(__ch))				\
1357 				__ch = TOUPPER(__ch);			\
1358 			break;						\
1359 		default:						\
1360 			abort();					\
1361 		}							\
1362 	}								\
1363 	NEEDSP(sp, 1, p);						\
1364 	*p++ = __ch;							\
1365 	++lbclen;							\
1366 } while (0)
1367 	conv = C_NOTSET;
1368 	for (rp = sp->repl, rpl = sp->repl_len, p = lb + lbclen; rpl--;) {
1369 		switch (ch = *rp++) {
1370 		case '&':
1371 			if (O_ISSET(sp, O_MAGIC)) {
1372 				no = 0;
1373 				goto subzero;
1374 			}
1375 			break;
1376 		case '\\':
1377 			if (rpl == 0)
1378 				break;
1379 			--rpl;
1380 			switch (ch = *rp) {
1381 			case '&':
1382 				++rp;
1383 				if (!O_ISSET(sp, O_MAGIC)) {
1384 					no = 0;
1385 					goto subzero;
1386 				}
1387 				break;
1388 			case '0': case '1': case '2': case '3': case '4':
1389 			case '5': case '6': case '7': case '8': case '9':
1390 				no = *rp++ - '0';
1391 subzero:			if (match[no].rm_so == -1 ||
1392 				    match[no].rm_eo == -1)
1393 					break;
1394 				mlen = match[no].rm_eo - match[no].rm_so;
1395 				for (t = ip + match[no].rm_so; mlen--; ++t)
1396 					OUTCH(*t, 0);
1397 				continue;
1398 			case 'e':
1399 			case 'E':
1400 				++rp;
1401 				conv = C_NOTSET;
1402 				continue;
1403 			case 'l':
1404 				++rp;
1405 				conv = C_ONELOWER;
1406 				continue;
1407 			case 'L':
1408 				++rp;
1409 				conv = C_LOWER;
1410 				continue;
1411 			case 'u':
1412 				++rp;
1413 				conv = C_ONEUPPER;
1414 				continue;
1415 			case 'U':
1416 				++rp;
1417 				conv = C_UPPER;
1418 				continue;
1419 			case '\r':
1420 				OUTCH(ch, 0);
1421 				continue;
1422 			default:
1423 				++rp;
1424 				break;
1425 			}
1426 		}
1427 		OUTCH(ch, 1);
1428 	}
1429 
1430 	*lbp = lb;			/* Update caller's information. */
1431 	*lbclenp = lbclen;
1432 	*lblenp = lblen;
1433 	return (0);
1434 }
1435