xref: /freebsd/contrib/tcsh/sh.dir.c (revision 6560ac57ce879857203bc456cdc3849808dc0700)
1 /*
2  * sh.dir.c: Directory manipulation functions
3  */
4 /*-
5  * Copyright (c) 1980, 1991 The Regents of the University of California.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 #include "sh.h"
33 #include "ed.h"
34 
35 /*
36  * C Shell - directory management
37  */
38 
39 static	Char			*agetcwd	(void);
40 static	void			 dstart		(const char *);
41 static	struct directory	*dfind		(Char *);
42 static	Char 			*dfollow	(Char *, int);
43 static	void 	 	 	 printdirs	(int);
44 static	Char 			*dgoto		(Char *);
45 static	void 	 	 	 dnewcwd	(struct directory *, int);
46 static	void 	 	 	 dset		(Char *);
47 static  void 			 dextract	(struct directory *);
48 static  int 			 skipargs	(Char ***, const char *,
49 						 const char *);
50 static	void			 dgetstack	(void);
51 static  Char			*dcanon_internal(Char *, Char *);
52 
53 static struct directory dhead INIT_ZERO_STRUCT;		/* "head" of loop */
54 static int    printd;			/* force name to be printed */
55 
56 int     bequiet = 0;		/* do not print dir stack -strike */
57 
58 static Char *
agetcwd(void)59 agetcwd(void)
60 {
61     char *buf;
62     Char *cwd;
63     size_t len;
64 
65     len = MAXPATHLEN;
66     buf = xmalloc(len);
67     while (getcwd(buf, len) == NULL) {
68 	int err;
69 
70 	err = errno;
71 	if (err != ERANGE) {
72 	    xfree(buf);
73 	    errno = err;
74 	    return NULL;
75 	}
76 	len *= 2;
77 	buf = xrealloc(buf, len);
78     }
79     if (*buf == '\0') {
80 	xfree(buf);
81 	return NULL;
82     }
83     cwd = SAVE(buf);
84     xfree(buf);
85     return cwd;
86 }
87 
88 static void
dstart(const char * from)89 dstart(const char *from)
90 {
91     xprintf(CGETS(12, 1, "%s: Trying to start from \"%s\"\n"), progname, from);
92 }
93 
94 /*
95  * dinit - initialize current working directory
96  */
97 void
dinit(Char * hp)98 dinit(Char *hp)
99 {
100     Char *cp, *tcp;
101     struct directory *dp;
102 
103     /* Don't believe the login shell home, because it may be a symlink */
104     tcp = agetcwd();
105     if (tcp == NULL) {
106 	xprintf("%s: %s\n", progname, strerror(errno));
107 	if (hp && *hp) {
108 	    char *xcp = short2str(hp);
109 	    dstart(xcp);
110 	    if (chdir(xcp) == -1)
111 		cp = NULL;
112 	    else
113 		cp = Strsave(hp);
114 	}
115 	else
116 	    cp = NULL;
117 	if (cp == NULL) {
118 	    dstart("/");
119 	    if (chdir("/") == -1)
120 		/* I am not even try to print an error message! */
121 		xexit(1);
122 	    cp = SAVE("/");
123 	}
124     }
125     else {
126 #ifdef S_IFLNK
127 	struct stat swd, shp;
128 	int swd_ok;
129 
130 	swd_ok = stat(short2str(tcp), &swd) == 0;
131 	/*
132 	 * See if $HOME is the working directory we got and use that
133 	 */
134 	if (swd_ok && hp && *hp && stat(short2str(hp), &shp) != -1 &&
135 	    DEV_DEV_COMPARE(swd.st_dev, shp.st_dev)  &&
136 		swd.st_ino == shp.st_ino)
137 	    cp = Strsave(hp);
138 	else {
139 	    char   *cwd;
140 
141 	    /*
142 	     * use PWD if we have it (for subshells)
143 	     */
144 	    if (swd_ok && (cwd = getenv("PWD")) != NULL) {
145 		if (stat(cwd, &shp) != -1 &&
146 			DEV_DEV_COMPARE(swd.st_dev, shp.st_dev) &&
147 		        swd.st_ino == shp.st_ino) {
148 		    tcp = SAVE(cwd);
149 		    cleanup_push(tcp, xfree);
150 		}
151 	    }
152 	    cp = dcanon(tcp, STRNULL);
153 	}
154 #else /* S_IFLNK */
155 	cp = dcanon(tcp, STRNULL);
156 #endif /* S_IFLNK */
157     }
158 
159     dp = xcalloc(sizeof(struct directory), 1);
160     dp->di_name = cp;
161     dp->di_count = 0;
162     dhead.di_next = dhead.di_prev = dp;
163     dp->di_next = dp->di_prev = &dhead;
164     printd = 0;
165     dnewcwd(dp, 0);
166     setcopy(STRdirstack, dp->di_name, VAR_READWRITE|VAR_NOGLOB);
167 }
168 
169 static void
dset(Char * dp)170 dset(Char *dp)
171 {
172     /*
173      * Don't call set() directly cause if the directory contains ` or
174      * other junk characters glob will fail.
175      */
176     setcopy(STRowd, varval(STRcwd), VAR_READWRITE|VAR_NOGLOB);
177     setcopy(STRcwd, dp, VAR_READWRITE|VAR_NOGLOB);
178     tsetenv(STRPWD, dp);
179 }
180 
181 #define DIR_PRINT	0x01	/* -p */
182 #define DIR_LONG  	0x02	/* -l */
183 #define DIR_VERT  	0x04	/* -v */
184 #define DIR_LINE  	0x08	/* -n */
185 #define DIR_SAVE 	0x10	/* -S */
186 #define DIR_LOAD	0x20	/* -L */
187 #define DIR_CLEAR	0x40	/* -c */
188 #define DIR_OLD	  	0x80	/* - */
189 
190 static int
skipargs(Char *** v,const char * dstr,const char * str)191 skipargs(Char ***v, const char *dstr, const char *str)
192 {
193     Char  **n = *v, *s;
194 
195     int dflag = 0, loop = 1;
196     for (n++; loop && *n != NULL && (*n)[0] == '-'; n++)
197 	if (*(s = &((*n)[1])) == '\0')	/* test for bare "-" argument */
198 	    dflag |= DIR_OLD;
199 	else if ((*n)[1] == '-' && (*n)[2] == '\0') {   /* test for -- */
200 	    n++;
201 	    break;
202 	} else {
203 	    char *p;
204 	    while (*s != '\0')	/* examine flags */ {
205 		if ((p = strchr(dstr, *s++)) != NULL)
206 		    dflag |= (1 << (p - dstr));
207 	        else
208 		    stderror(ERR_DIRUS, short2str(**v), dstr, str);
209 	    }
210 	}
211     if (*n && (dflag & DIR_OLD))
212 	stderror(ERR_DIRUS, short2str(**v), dstr, str);
213     *v = n;
214     /* make -l, -v, and -n imply -p */
215     if (dflag & (DIR_LONG|DIR_VERT|DIR_LINE))
216 	dflag |= DIR_PRINT;
217     return dflag;
218 }
219 
220 /*
221  * dodirs - list all directories in directory loop
222  */
223 /*ARGSUSED*/
224 void
dodirs(Char ** v,struct command * c)225 dodirs(Char **v, struct command *c)
226 {
227     static const char flags[] = "plvnSLc";
228     int dflag = skipargs(&v, flags, "");
229 
230     USE(c);
231     if ((dflag & DIR_CLEAR) != 0) {
232 	struct directory *dp, *fdp;
233 	for (dp = dcwd->di_next; dp != dcwd; ) {
234 	    fdp = dp;
235 	    dp = dp->di_next;
236 	    if (fdp != &dhead)
237 		dfree(fdp);
238 	}
239 	dhead.di_next = dhead.di_prev = dp;
240 	dp->di_next = dp->di_prev = &dhead;
241     }
242     if ((dflag & DIR_LOAD) != 0)
243 	loaddirs(*v);
244     else if ((dflag & DIR_SAVE) != 0)
245 	recdirs(*v, 1);
246 
247     if (*v && (dflag & (DIR_SAVE|DIR_LOAD)))
248 	v++;
249 
250     if (*v != NULL || (dflag & DIR_OLD))
251 	stderror(ERR_DIRUS, "dirs", flags, "");
252     if ((dflag & (DIR_CLEAR|DIR_LOAD|DIR_SAVE)) == 0 || (dflag & DIR_PRINT))
253 	printdirs(dflag);
254 }
255 
256 static void
printdirs(int dflag)257 printdirs(int dflag)
258 {
259     struct directory *dp;
260     Char   *s, *user;
261     int     idx, len, cur;
262 
263     dp = dcwd;
264     idx = 0;
265     cur = 0;
266     do {
267 	if (dp == &dhead)
268 	    continue;
269 	if (dflag & DIR_VERT) {
270 	    xprintf("%d\t", idx++);
271 	    cur = 0;
272 	}
273 	s = dp->di_name;
274 	user = NULL;
275 	if (!(dflag & DIR_LONG) && (user = getusername(&s)) != NULL)
276 	    len = (int) (Strlen(user) + Strlen(s) + 2);
277 	else
278 	    len = (int) (Strlen(s) + 1);
279 
280 	cur += len;
281 	if ((dflag & DIR_LINE) && cur >= TermH - 1 && len < TermH) {
282 	    xputchar('\n');
283 	    cur = len;
284 	}
285 	if (user)
286 	    xprintf("~%S", user);
287 	xprintf("%-S%c", s, (dflag & DIR_VERT) ? '\n' : ' ');
288     } while ((dp = dp->di_prev) != dcwd);
289     if (!(dflag & DIR_VERT))
290 	xputchar('\n');
291 }
292 
293 void
dtildepr(Char * dir)294 dtildepr(Char *dir)
295 {
296     Char* user;
297     if ((user = getusername(&dir)) != NULL)
298 	xprintf("~%-S%S", user, dir);
299     else
300 	xprintf("%S", dir);
301 }
302 
303 void
dtilde(void)304 dtilde(void)
305 {
306     struct directory *d = dcwd;
307 
308     do {
309 	if (d == &dhead)
310 	    continue;
311 	d->di_name = dcanon_internal(d->di_name, STRNULL);
312     } while ((d = d->di_prev) != dcwd);
313 
314     dset(dcwd->di_name);
315 }
316 
317 
318 /* dnormalize():
319  *	The path will be normalized if it
320  *	1) is "..",
321  *	2) or starts with "../",
322  *	3) or ends with "/..",
323  *	4) or contains the string "/../",
324  *	then it will be normalized, unless those strings are quoted.
325  *	Otherwise, a copy is made and sent back.
326  */
327 Char   *
dnormalize(const Char * cp,int expnd)328 dnormalize(const Char *cp, int expnd)
329 {
330 
331 /* return true if dp is of the form "../xxx" or "/../xxx" */
332 #define IS_DOTDOT(sp, p) (ISDOTDOT(p) && ((p) == (sp) || *((p) - 1) == '/'))
333 #define IS_DOT(sp, p) (ISDOT(p) && ((p) == (sp) || *((p) - 1) == '/'))
334 
335 #ifdef S_IFLNK
336     if (expnd) {
337 	struct Strbuf buf = Strbuf_INIT;
338  	int     dotdot = 0;
339 	Char   *dp, *cwd;
340 	const Char *start = cp;
341 # ifdef HAVE_SLASHSLASH
342 	int slashslash;
343 # endif /* HAVE_SLASHSLASH */
344 
345 	/*
346 	 * count the number of "../xxx" or "xxx/../xxx" in the path
347 	 */
348 	for ( ; *cp && *(cp + 1); cp++)
349 	    if (IS_DOTDOT(start, cp))
350 	        dotdot++;
351 
352 	/*
353 	 * if none, we are done.
354 	 */
355         if (dotdot == 0)
356 	    return (Strsave(start));
357 
358 # ifdef notdef
359 	struct stat sb;
360 	/*
361 	 * We disable this test because:
362 	 * cd /tmp; mkdir dir1 dir2; cd dir2; ln -s /tmp/dir1; cd dir1;
363 	 * echo ../../dir1 does not expand. We had enabled this before
364 	 * because it was bothering people with expansions in compilation
365 	 * lines like -I../../foo. Maybe we need some kind of finer grain
366 	 * control?
367 	 *
368 	 * If the path doesn't exist, we are done too.
369 	 */
370 	if (lstat(short2str(start), &sb) != 0 && errno == ENOENT)
371 	    return (Strsave(start));
372 # endif
373 
374 	cwd = xmalloc((Strlen(dcwd->di_name) + 3) * sizeof(Char));
375 	(void) Strcpy(cwd, dcwd->di_name);
376 
377 	/*
378 	 * If the path starts with a slash, we are not relative to
379 	 * the current working directory.
380 	 */
381 	if (ABSOLUTEP(start))
382 	    *cwd = '\0';
383 # ifdef HAVE_SLASHSLASH
384 	slashslash = cwd[0] == '/' && cwd[1] == '/';
385 # endif /* HAVE_SLASHSLASH */
386 
387 	/*
388 	 * Ignore . and count ..'s
389 	 */
390 	cp = start;
391 	do {
392 	    dotdot = 0;
393 	    buf.len = 0;
394 	    while (*cp)
395 	        if (IS_DOT(start, cp)) {
396 	            if (*++cp)
397 	                cp++;
398 	        }
399 	        else if (IS_DOTDOT(start, cp)) {
400 		    if (buf.len != 0)
401 		        break; /* finish analyzing .././../xxx/[..] */
402 		    dotdot++;
403 		    cp += 2;
404 		    if (*cp)
405 		        cp++;
406 	        }
407 	        else
408 		    Strbuf_append1(&buf, *cp++);
409 
410 	    Strbuf_terminate(&buf);
411 	    while (dotdot > 0)
412 	        if ((dp = Strrchr(cwd, '/')) != NULL) {
413 # ifdef HAVE_SLASHSLASH
414 		    if (dp == &cwd[1])
415 		        slashslash = 1;
416 # endif /* HAVE_SLASHSLASH */
417 		        *dp = '\0';
418 		        dotdot--;
419 	        }
420 	        else
421 		    break;
422 
423 	    if (!*cwd) {	/* too many ..'s, starts with "/" */
424 	        cwd[0] = '/';
425 # ifdef HAVE_SLASHSLASH
426 		/*
427 		 * Only append another slash, if already the former cwd
428 		 * was in a double-slash path.
429 		 */
430 		cwd[1] = slashslash ? '/' : '\0';
431 		cwd[2] = '\0';
432 # else /* !HAVE_SLASHSLASH */
433 		cwd[1] = '\0';
434 # endif /* HAVE_SLASHSLASH */
435 	    }
436 # ifdef HAVE_SLASHSLASH
437 	    else if (slashslash && cwd[1] == '\0') {
438 		cwd[1] = '/';
439 		cwd[2] = '\0';
440 	    }
441 # endif /* HAVE_SLASHSLASH */
442 
443 	    if (buf.len != 0) {
444 		size_t i;
445 
446 		i = Strlen(cwd);
447 		if (TRM(cwd[i - 1]) != '/') {
448 		    cwd[i++] = '/';
449 		    cwd[i] = '\0';
450 		}
451 	        dp = Strspl(cwd, TRM(buf.s[0]) == '/' ? &buf.s[1] : buf.s);
452 	        xfree(cwd);
453 	        cwd = dp;
454 		i = Strlen(cwd) - 1;
455 	        if (TRM(cwd[i]) == '/')
456 		    cwd[i] = '\0';
457 	    }
458 	    /* Reduction of ".." following the stuff we collected in buf
459 	     * only makes sense if the directory item in buf really exists.
460 	     * Avoid reduction of "-I../.." (typical compiler call) to ""
461 	     * or "/usr/nonexistant/../bin" to "/usr/bin":
462 	     */
463 	    if (cwd[0]) {
464 	        struct stat exists;
465 		if (0 != stat(short2str(cwd), &exists)) {
466 		    xfree(buf.s);
467 		    xfree(cwd);
468 		    return Strsave(start);
469 		}
470 	    }
471 	} while (*cp != '\0');
472 	xfree(buf.s);
473 	return cwd;
474     }
475 #endif /* S_IFLNK */
476     return Strsave(cp);
477 }
478 
479 
480 /*
481  * dochngd - implement chdir command.
482  */
483 /*ARGSUSED*/
484 void
dochngd(Char ** v,struct command * c)485 dochngd(Char **v, struct command *c)
486 {
487     Char *cp;
488     struct directory *dp;
489     int dflag = skipargs(&v, "plvn", "[-|<dir>]");
490 
491     USE(c);
492     printd = 0;
493     cp = (dflag & DIR_OLD) ? varval(STRowd) : *v;
494 
495     if (cp == NULL) {
496 	if (!cdtohome)
497 	    stderror(ERR_NAME | ERR_TOOFEW);
498 	else if ((cp = varval(STRhome)) == STRNULL || *cp == 0)
499 	    stderror(ERR_NAME | ERR_NOHOMEDIR);
500 	if (chdir(short2str(cp)) < 0)
501 	    stderror(ERR_NAME | ERR_CANTCHANGE);
502 	cp = Strsave(cp);
503     }
504     else if ((dflag & DIR_OLD) == 0 && v[1] != NULL) {
505 	stderror(ERR_NAME | ERR_TOOMANY);
506 	/* NOTREACHED */
507 	return;
508     }
509     else if ((dp = dfind(cp)) != 0) {
510 	char   *tmp;
511 
512 	printd = 1;
513 	if (chdir(tmp = short2str(dp->di_name)) < 0)
514 	    stderror(ERR_SYSTEM, tmp, strerror(errno));
515 	dcwd->di_prev->di_next = dcwd->di_next;
516 	dcwd->di_next->di_prev = dcwd->di_prev;
517 	dfree(dcwd);
518 	dnewcwd(dp, dflag);
519 	return;
520     }
521     else
522 	if ((cp = dfollow(cp, dflag & DIR_OLD)) == NULL)
523 	    return;
524     dp = xcalloc(sizeof(struct directory), 1);
525     dp->di_name = cp;
526     dp->di_count = 0;
527     dp->di_next = dcwd->di_next;
528     dp->di_prev = dcwd->di_prev;
529     dp->di_prev->di_next = dp;
530     dp->di_next->di_prev = dp;
531     dfree(dcwd);
532     dnewcwd(dp, dflag);
533 }
534 
535 static Char *
dgoto(Char * cp)536 dgoto(Char *cp)
537 {
538     Char *dp, *ret;
539 
540     if (!ABSOLUTEP(cp))
541     {
542 	Char *p, *q;
543 	size_t cwdlen;
544 
545 	cwdlen = Strlen(dcwd->di_name);
546 	if (cwdlen == 1)	/* root */
547 	    cwdlen = 0;
548 	dp = xmalloc((cwdlen + Strlen(cp) + 2) * sizeof(Char));
549 	for (p = dp, q = dcwd->di_name; (*p++ = *q++) != '\0';)
550 	    continue;
551 	if (cwdlen)
552 	    p[-1] = '/';
553 	else
554 	    p--;		/* don't add a / after root */
555 	Strcpy(p, cp);
556 	xfree(cp);
557 	cp = dp;
558 	dp += cwdlen;
559     }
560     else
561 	dp = cp;
562 
563 #if defined(WINNT_NATIVE)
564     return agetcwd();
565 #elif defined(__CYGWIN__)
566     if (ABSOLUTEP(cp) && cp[1] == ':') { /* Only DOS paths are treated that way */
567 	return agetcwd();
568     } else {
569     	ret = dcanon(cp, dp);
570     }
571 #else /* !WINNT_NATIVE */
572     ret = dcanon(cp, dp);
573 #endif /* WINNT_NATIVE */
574     return ret;
575 }
576 
577 /*
578  * dfollow - change to arg directory; fall back on cdpath if not valid
579  */
580 static Char *
dfollow(Char * cp,int old)581 dfollow(Char *cp, int old)
582 {
583     Char *dp;
584     struct varent *c;
585     int serrno;
586 
587     cp = old ? Strsave(cp) : globone(cp, G_ERROR);
588     cleanup_push(cp, xfree);
589 #ifdef apollo
590     if (Strchr(cp, '`')) {
591 	char *dptr;
592 	if (chdir(dptr = short2str(cp)) < 0)
593 	    stderror(ERR_SYSTEM, dptr, strerror(errno));
594 	dp = agetcwd();
595 	cleanup_push(dp, xfree);
596 	if (dp != NULL) {
597 	    cleanup_until(cp);
598 	    return dgoto(dp);
599 	}
600 	else
601 	    stderror(ERR_SYSTEM, dptr, strerror(errno));
602     }
603 #endif /* apollo */
604 
605     /*
606      * if we are ignoring symlinks, try to fix relatives now.
607      * if we are expading symlinks, it should be done by now.
608      */
609     dp = dnormalize(cp, symlinks == SYM_IGNORE);
610     if (chdir(short2str(dp)) >= 0) {
611         cleanup_until(cp);
612         return dgoto(dp);
613     }
614     else {
615         xfree(dp);
616         if (chdir(short2str(cp)) >= 0) {
617 	    cleanup_ignore(cp);
618 	    cleanup_until(cp);
619 	    return dgoto(cp);
620 	}
621 	else if (errno != ENOENT && errno != ENOTDIR) {
622 	    int err;
623 
624 	    err = errno;
625 	    stderror(ERR_SYSTEM, short2str(cp), strerror(err));
626 	}
627 	serrno = errno;
628     }
629 
630     if (cp[0] != '/' && !prefix(STRdotsl, cp) && !prefix(STRdotdotsl, cp)
631 	&& (c = adrof(STRcdpath)) && c->vec != NULL) {
632 	struct Strbuf buf = Strbuf_INIT;
633 	Char  **cdp;
634 
635 	for (cdp = c->vec; *cdp; cdp++) {
636 	    size_t len = Strlen(*cdp);
637 	    buf.len = 0;
638 	    if (len > 0) {
639 		Strbuf_append(&buf, *cdp);
640 		if ((*cdp)[len - 1] != '/')
641 		    Strbuf_append1(&buf, '/');
642 	    }
643 	    Strbuf_append(&buf, cp);
644 	    Strbuf_terminate(&buf);
645 	    /*
646 	     * We always want to fix the directory here
647 	     * If we are normalizing symlinks
648 	     */
649 	    dp = dnormalize(buf.s, symlinks == SYM_IGNORE ||
650 				   symlinks == SYM_EXPAND);
651 	    if (chdir(short2str(dp)) >= 0) {
652 		printd = 1;
653 		xfree(buf.s);
654 		cleanup_until(cp);
655 		return dgoto(dp);
656 	    }
657 	    else if (chdir(short2str(cp)) >= 0) {
658 		printd = 1;
659 		xfree(dp);
660 		xfree(buf.s);
661 		cleanup_ignore(cp);
662 		cleanup_until(cp);
663 		return dgoto(cp);
664 	    }
665 	    xfree(dp);
666 	}
667 	xfree(buf.s);
668     }
669     dp = varval(cp);
670     if ((dp[0] == '/' || dp[0] == '.') && chdir(short2str(dp)) >= 0) {
671 	cleanup_until(cp);
672 	cp = Strsave(dp);
673 	printd = 1;
674 	return dgoto(cp);
675     }
676     /*
677      * on login source of ~/.cshdirs, errors are eaten. the dir stack is all
678      * directories we could get to.
679      */
680     if (!bequiet)
681 	stderror(ERR_SYSTEM, short2str(cp), strerror(serrno));
682     cleanup_until(cp);
683     return (NULL);
684 }
685 
686 
687 /*
688  * dopushd - push new directory onto directory stack.
689  *	with no arguments exchange top and second.
690  *	with numeric argument (+n) bring it to top.
691  */
692 /*ARGSUSED*/
693 void
dopushd(Char ** v,struct command * c)694 dopushd(Char **v, struct command *c)
695 {
696     struct directory *dp;
697     Char *cp;
698     int dflag = skipargs(&v, "plvn", " [-|<dir>|+<n>]");
699 
700     USE(c);
701     printd = 1;
702     cp = (dflag & DIR_OLD) ? varval(STRowd) : *v;
703 
704     if (cp == NULL) {
705 	if (adrof(STRpushdtohome)) {
706 	    if ((cp = varval(STRhome)) == STRNULL || *cp == 0)
707 		stderror(ERR_NAME | ERR_NOHOMEDIR);
708 	    if (chdir(short2str(cp)) < 0)
709 		stderror(ERR_NAME | ERR_CANTCHANGE);
710 	    if ((cp = dfollow(cp, dflag & DIR_OLD)) == NULL)
711 		return;
712 	    dp = xcalloc(sizeof(struct directory), 1);
713 	    dp->di_name = cp;
714 	    dp->di_count = 0;
715 	    dp->di_prev = dcwd;
716 	    dp->di_next = dcwd->di_next;
717 	    dcwd->di_next = dp;
718 	    dp->di_next->di_prev = dp;
719 	}
720 	else {
721 	    char   *tmp;
722 
723 	    if ((dp = dcwd->di_prev) == &dhead)
724 		dp = dhead.di_prev;
725 	    if (dp == dcwd)
726 		stderror(ERR_NAME | ERR_NODIR);
727 	    if (chdir(tmp = short2str(dp->di_name)) < 0)
728 		stderror(ERR_SYSTEM, tmp, strerror(errno));
729 	    dp->di_prev->di_next = dp->di_next;
730 	    dp->di_next->di_prev = dp->di_prev;
731 	    dp->di_next = dcwd->di_next;
732 	    dp->di_prev = dcwd;
733 	    dcwd->di_next->di_prev = dp;
734 	    dcwd->di_next = dp;
735 	}
736     }
737     else if ((dflag & DIR_OLD) == 0 && v[1] != NULL) {
738 	stderror(ERR_NAME | ERR_TOOMANY);
739 	/* NOTREACHED */
740 	return;
741     }
742     else if ((dp = dfind(cp)) != NULL) {
743 	char   *tmp;
744 
745 	if (chdir(tmp = short2str(dp->di_name)) < 0)
746 	    stderror(ERR_SYSTEM, tmp, strerror(errno));
747 	/*
748 	 * kfk - 10 Feb 1984 - added new "extraction style" pushd +n
749 	 */
750 	if (adrof(STRdextract))
751 	    dextract(dp);
752     }
753     else {
754 	Char *ccp;
755 
756 	if ((ccp = dfollow(cp, dflag & DIR_OLD)) == NULL)
757 	    return;
758 	dp = xcalloc(sizeof(struct directory), 1);
759 	dp->di_name = ccp;
760 	dp->di_count = 0;
761 	dp->di_prev = dcwd;
762 	dp->di_next = dcwd->di_next;
763 	dcwd->di_next = dp;
764 	dp->di_next->di_prev = dp;
765     }
766     dnewcwd(dp, dflag);
767 }
768 
769 /*
770  * dfind - find a directory if specified by numeric (+n) argument
771  */
772 static struct directory *
dfind(Char * cp)773 dfind(Char *cp)
774 {
775     struct directory *dp;
776     int i;
777     Char *ep;
778 
779     if (*cp++ != '+')
780 	return (0);
781     for (ep = cp; Isdigit(*ep); ep++)
782 	continue;
783     if (*ep)
784 	return (0);
785     i = getn(cp);
786     if (i <= 0)
787 	return (0);
788     for (dp = dcwd; i != 0; i--) {
789 	if ((dp = dp->di_prev) == &dhead)
790 	    dp = dp->di_prev;
791 	if (dp == dcwd)
792 	    stderror(ERR_NAME | ERR_DEEP);
793     }
794     return (dp);
795 }
796 
797 /*
798  * dopopd - pop a directory out of the directory stack
799  *	with a numeric argument just discard it.
800  */
801 /*ARGSUSED*/
802 void
dopopd(Char ** v,struct command * c)803 dopopd(Char **v, struct command *c)
804 {
805     Char *cp;
806     struct directory *dp, *p = NULL;
807     int dflag = skipargs(&v, "plvn", " [-|+<n>]");
808 
809     USE(c);
810     printd = 1;
811     cp = (dflag & DIR_OLD) ? varval(STRowd) : *v;
812 
813     if (cp == NULL)
814 	dp = dcwd;
815     else if ((dflag & DIR_OLD) == 0 && v[1] != NULL) {
816 	stderror(ERR_NAME | ERR_TOOMANY);
817 	/* NOTREACHED */
818 	return;
819     }
820     else if ((dp = dfind(cp)) == 0)
821 	stderror(ERR_NAME | ERR_BADDIR);
822     if (dp->di_prev == &dhead && dp->di_next == &dhead)
823 	stderror(ERR_NAME | ERR_EMPTY);
824     if (dp == dcwd) {
825 	char   *tmp;
826 
827 	if ((p = dp->di_prev) == &dhead)
828 	    p = dhead.di_prev;
829 	if (chdir(tmp = short2str(p->di_name)) < 0)
830 	    stderror(ERR_SYSTEM, tmp, strerror(errno));
831     }
832     dp->di_prev->di_next = dp->di_next;
833     dp->di_next->di_prev = dp->di_prev;
834     dfree(dp);
835     if (dp == dcwd) {
836         dnewcwd(p, dflag);
837     }
838     else {
839 	printdirs(dflag);
840     }
841 }
842 
843 /*
844  * dfree - free the directory (or keep it if it still has ref count)
845  */
846 void
dfree(struct directory * dp)847 dfree(struct directory *dp)
848 {
849 
850     if (dp->di_count != 0) {
851 	dp->di_next = dp->di_prev = 0;
852     }
853     else {
854 	xfree(dp->di_name);
855 	xfree(dp);
856     }
857 }
858 
859 /*
860  * dcanon - a safe version of dcanon_internal that arranges for cleanup
861  */
862 Char *
dcanon(Char * cp,Char * p)863 dcanon(Char *cp, Char *p)
864 {
865     cleanup_push(cp, xfree);
866     p = dcanon_internal(cp, p);
867     // coverity[use_after_free] we use the pointer as a marker
868     cleanup_ignore(cp);
869     cleanup_until(cp);
870     return p;
871 }
872 
873 /*
874  * dcanon_internal - canonicalize the pathname, removing excess ./ and ../ etc.
875  *	we are of course assuming that the file system is standardly
876  *	constructed (always have ..'s, directories have links)
877  */
878 static Char *
dcanon_internal(Char * cp,Char * p)879 dcanon_internal(Char *cp, Char *p)
880 {
881     Char *sp;
882     Char *p1, *p2;	/* general purpose */
883     int    slash;
884 #ifdef HAVE_SLASHSLASH
885     int    slashslash;
886 #endif /* HAVE_SLASHSLASH */
887     size_t  clen;
888 
889 #ifdef S_IFLNK			/* if we have symlinks */
890     Char *mlink, *newcp;
891     char *tlink;
892     size_t cc;
893 #endif /* S_IFLNK */
894 
895     clen = Strlen(cp);
896 
897     /*
898      * christos: if the path given does not start with a slash prepend cwd. If
899      * cwd does not start with a slash or the result would be too long try to
900      * correct it.
901      */
902     if (!ABSOLUTEP(cp)) {
903 	Char *tmpdir;
904 	size_t	len;
905 
906 	p1 = varval(STRcwd);
907 	if (p1 == STRNULL || !ABSOLUTEP(p1)) {
908 	    Char *new_cwd = agetcwd();
909 
910 	    if (new_cwd == NULL) {
911 		xprintf("%s: %s\n", progname, strerror(errno));
912 		setcopy(STRcwd, str2short("/"), VAR_READWRITE|VAR_NOGLOB);
913 	    }
914 	    else
915 		setv(STRcwd, new_cwd, VAR_READWRITE|VAR_NOGLOB);
916 	    p1 = varval(STRcwd);
917 	}
918 	len = Strlen(p1);
919 	tmpdir = xmalloc((len + clen + 2) * sizeof (*tmpdir));
920 	(void) Strcpy(tmpdir, p1);
921 	(void) Strcat(tmpdir, STRslash);
922 	(void) Strcat(tmpdir, cp);
923 	xfree(cp);
924 	cp = p = tmpdir;
925     }
926 
927 #ifdef HAVE_SLASHSLASH
928     slashslash = (cp[0] == '/' && cp[1] == '/');
929 #endif /* HAVE_SLASHSLASH */
930 
931     while (*p) {		/* for each component */
932 	sp = p;			/* save slash address */
933 	while (*++p == '/')	/* flush extra slashes */
934 	    continue;
935 	if (p != ++sp)
936 	    for (p1 = sp, p2 = p; (*p1++ = *p2++) != '\0';)
937 		continue;
938 	p = sp;			/* save start of component */
939 	slash = 0;
940 	if (*p)
941 	    while (*++p)	/* find next slash or end of path */
942 		if (*p == '/') {
943 		    slash = 1;
944 		    *p = 0;
945 		    break;
946 		}
947 
948 #ifdef HAVE_SLASHSLASH
949 	if (&cp[1] == sp && sp[0] == '.' && sp[1] == '.' && sp[2] == '\0')
950 	    slashslash = 1;
951 #endif /* HAVE_SLASHSLASH */
952 	if (*sp == '\0') {	/* if component is null */
953 	    if (--sp == cp)	/* if path is one char (i.e. /) */
954 		break;
955 	    else
956 		*sp = '\0';
957 	}
958 	else if (sp[0] == '.' && sp[1] == 0) {
959 	    if (slash) {
960 		for (p1 = sp, p2 = p + 1; (*p1++ = *p2++) != '\0';)
961 		    continue;
962 		p = --sp;
963 	    }
964 	    else if (--sp != cp)
965 		*sp = '\0';
966 	    else
967 		sp[1] = '\0';
968 	}
969 	else if (sp[0] == '.' && sp[1] == '.' && sp[2] == 0) {
970 	    /*
971 	     * We have something like "yyy/xxx/..", where "yyy" can be null or
972 	     * a path starting at /, and "xxx" is a single component. Before
973 	     * compressing "xxx/..", we want to expand "yyy/xxx", if it is a
974 	     * symbolic link.
975 	     */
976 	    *--sp = 0;		/* form the pathname for readlink */
977 #ifdef S_IFLNK			/* if we have symlinks */
978 	    if (sp != cp && /* symlinks != SYM_IGNORE && */
979 		(tlink = areadlink(short2str(cp))) != NULL) {
980 		mlink = str2short(tlink);
981 		xfree(tlink);
982 
983 		if (slash)
984 		    *p = '/';
985 		/*
986 		 * Point p to the '/' in "/..", and restore the '/'.
987 		 */
988 		*(p = sp) = '/';
989 		if (*mlink != '/') {
990 		    /*
991 		     * Relative path, expand it between the "yyy/" and the
992 		     * "/..". First, back sp up to the character past "yyy/".
993 		     */
994 		    while (*--sp != '/')
995 			continue;
996 		    sp++;
997 		    *sp = 0;
998 		    /*
999 		     * New length is "yyy/" + mlink + "/.." and rest
1000 		     */
1001 		    p1 = newcp = xmalloc(((sp - cp) + Strlen(mlink) +
1002 					  Strlen(p) + 1) * sizeof(Char));
1003 		    /*
1004 		     * Copy new path into newcp
1005 		     */
1006 		    for (p2 = cp; (*p1++ = *p2++) != '\0';)
1007 			continue;
1008 		    for (p1--, p2 = mlink; (*p1++ = *p2++) != '\0';)
1009 			continue;
1010 		    for (p1--, p2 = p; (*p1++ = *p2++) != '\0';)
1011 			continue;
1012 		    /*
1013 		     * Restart canonicalization at expanded "/xxx".
1014 		     */
1015 		    p = sp - cp - 1 + newcp;
1016 		}
1017 		else {
1018 		    newcp = Strspl(mlink, p);
1019 		    /*
1020 		     * Restart canonicalization at beginning
1021 		     */
1022 		    p = newcp;
1023 		}
1024 		xfree(cp);
1025 		cp = newcp;
1026 #ifdef HAVE_SLASHSLASH
1027                 slashslash = (cp[0] == '/' && cp[1] == '/');
1028 #endif /* HAVE_SLASHSLASH */
1029 		continue;	/* canonicalize the link */
1030 	    }
1031 #endif /* S_IFLNK */
1032 	    *sp = '/';
1033 	    if (sp != cp)
1034 		while (*--sp != '/')
1035 		    continue;
1036 	    if (slash) {
1037 		for (p1 = sp + 1, p2 = p + 1; (*p1++ = *p2++) != '\0';)
1038 		    continue;
1039 		p = sp;
1040 	    }
1041 	    else if (cp == sp)
1042 		*++sp = '\0';
1043 	    else
1044 		*sp = '\0';
1045 	}
1046 	else {			/* normal dir name (not . or .. or nothing) */
1047 
1048 #ifdef S_IFLNK			/* if we have symlinks */
1049 	    if (sp != cp && symlinks == SYM_CHASE &&
1050 		(tlink = areadlink(short2str(cp))) != NULL) {
1051 		mlink = str2short(tlink);
1052 		xfree(tlink);
1053 
1054 		/*
1055 		 * restore the '/'.
1056 		 */
1057 		if (slash)
1058 		    *p = '/';
1059 
1060 		/*
1061 		 * point sp to p (rather than backing up).
1062 		 */
1063 		sp = p;
1064 
1065 		if (*mlink != '/') {
1066 		    /*
1067 		     * Relative path, expand it between the "yyy/" and the
1068 		     * remainder. First, back sp up to the character past
1069 		     * "yyy/".
1070 		     */
1071 		    while (*--sp != '/')
1072 			continue;
1073 		    sp++;
1074 		    *sp = 0;
1075 		    /*
1076 		     * New length is "yyy/" + mlink + "/.." and rest
1077 		     */
1078 		    p1 = newcp = xmalloc(((sp - cp) + Strlen(mlink) +
1079 					  Strlen(p) + 1) * sizeof(Char));
1080 		    /*
1081 		     * Copy new path into newcp
1082 		     */
1083 		    for (p2 = cp; (*p1++ = *p2++) != '\0';)
1084 			continue;
1085 		    for (p1--, p2 = mlink; (*p1++ = *p2++) != '\0';)
1086 			continue;
1087 		    for (p1--, p2 = p; (*p1++ = *p2++) != '\0';)
1088 			continue;
1089 		    /*
1090 		     * Restart canonicalization at expanded "/xxx".
1091 		     */
1092 		    p = sp - cp - 1 + newcp;
1093 		}
1094 		else {
1095 		    newcp = Strspl(mlink, p);
1096 		    /*
1097 		     * Restart canonicalization at beginning
1098 		     */
1099 		    p = newcp;
1100 		}
1101 		xfree(cp);
1102 		cp = newcp;
1103 #ifdef HAVE_SLASHSLASH
1104                 slashslash = (cp[0] == '/' && cp[1] == '/');
1105 #endif /* HAVE_SLASHSLASH */
1106 		continue;	/* canonicalize the mlink */
1107 	    }
1108 #endif /* S_IFLNK */
1109 	    if (slash)
1110 		*p = '/';
1111 	}
1112     }
1113 
1114     /*
1115      * fix home...
1116      */
1117 #ifdef S_IFLNK
1118     p1 = varval(STRhome);
1119     cc = Strlen(p1);
1120     /*
1121      * See if we're not in a subdir of STRhome
1122      */
1123     if (p1 && *p1 == '/' && (Strncmp(p1, cp, cc) != 0 ||
1124 	(cp[cc] != '/' && cp[cc] != '\0'))) {
1125 	static ino_t home_ino = (ino_t) -1;
1126 	static dev_t home_dev = (dev_t) -1;
1127 	static Char *home_ptr = NULL;
1128 	struct stat statbuf;
1129 	int found;
1130 	Char *copy;
1131 
1132 	/*
1133 	 * Get dev and ino of STRhome
1134 	 */
1135 	if (home_ptr != p1 &&
1136 	    stat(short2str(p1), &statbuf) != -1) {
1137 	    home_dev = statbuf.st_dev;
1138 	    home_ino = statbuf.st_ino;
1139 	    home_ptr = p1;
1140 	}
1141 	/*
1142 	 * Start comparing dev & ino backwards
1143 	 */
1144 	p2 = copy = Strsave(cp);
1145 	found = 0;
1146 	while (*p2 && stat(short2str(p2), &statbuf) != -1) {
1147 	    if (DEV_DEV_COMPARE(statbuf.st_dev, home_dev) &&
1148 			statbuf.st_ino == home_ino) {
1149 			found = 1;
1150 			break;
1151 	    }
1152 	    if ((sp = Strrchr(p2, '/')) != NULL)
1153 		*sp = '\0';
1154 	}
1155 	/*
1156 	 * See if we found it
1157 	 */
1158 	if (*p2 && found) {
1159 	    /*
1160 	     * Use STRhome to make '~' work
1161 	     */
1162 	    newcp = Strspl(p1, cp + Strlen(p2));
1163 	    xfree(cp);
1164 	    cp = newcp;
1165 	}
1166 	xfree(copy);
1167     }
1168 #endif /* S_IFLNK */
1169 
1170 #ifdef HAVE_SLASHSLASH
1171     if (slashslash) {
1172 	if (cp[1] != '/') {
1173 	    p = xmalloc((Strlen(cp) + 2) * sizeof(Char));
1174 	    *p = '/';
1175 	    (void) Strcpy(&p[1], cp);
1176 	    xfree(cp);
1177 	    cp = p;
1178 	}
1179     }
1180     if (cp[1] == '/' && cp[2] == '/') {
1181 	for (p1 = &cp[1], p2 = &cp[2]; (*p1++ = *p2++) != '\0';)
1182 	    continue;
1183     }
1184 #endif /* HAVE_SLASHSLASH */
1185     return cp;
1186 }
1187 
1188 
1189 /*
1190  * dnewcwd - make a new directory in the loop the current one
1191  */
1192 static void
dnewcwd(struct directory * dp,int dflag)1193 dnewcwd(struct directory *dp, int dflag)
1194 {
1195     int print;
1196 
1197     if (adrof(STRdunique)) {
1198 	struct directory *dn;
1199 
1200 	for (dn = dhead.di_prev; dn != &dhead; dn = dn->di_prev)
1201 	    if (dn != dp && Strcmp(dn->di_name, dp->di_name) == 0) {
1202 		dn->di_next->di_prev = dn->di_prev;
1203 		dn->di_prev->di_next = dn->di_next;
1204 		dfree(dn);
1205 		break;
1206 	    }
1207     }
1208     dcwd = dp;
1209     dset(dcwd->di_name);
1210     dgetstack();
1211     print = printd;		/* if printd is set, print dirstack... */
1212     if (adrof(STRpushdsilent))	/* but pushdsilent overrides printd... */
1213 	print = 0;
1214     if (dflag & DIR_PRINT)	/* but DIR_PRINT overrides pushdsilent... */
1215 	print = 1;
1216     if (bequiet)		/* and bequiet overrides everything */
1217 	print = 0;
1218     if (print)
1219 	printdirs(dflag);
1220     cwd_cmd();			/* PWP: run the defined cwd command */
1221 }
1222 
1223 void
dsetstack(void)1224 dsetstack(void)
1225 {
1226     Char **cp;
1227     struct varent *vp;
1228     struct directory *dn, *dp;
1229 
1230     if ((vp = adrof(STRdirstack)) == NULL || vp->vec == NULL)
1231 	return;
1232 
1233     /* Free the whole stack */
1234     while ((dn = dhead.di_prev) != &dhead) {
1235 	dn->di_next->di_prev = dn->di_prev;
1236 	dn->di_prev->di_next = dn->di_next;
1237 	if (dn != dcwd)
1238 	    dfree(dn);
1239     }
1240 
1241     /* thread the current working directory */
1242     dhead.di_prev = dhead.di_next = dcwd;
1243     dcwd->di_next = dcwd->di_prev = &dhead;
1244 
1245     /* put back the stack */
1246     for (cp = vp->vec; cp && *cp && **cp; cp++) {
1247 	dp = xcalloc(sizeof(struct directory), 1);
1248 	dp->di_name = Strsave(*cp);
1249 	dp->di_count = 0;
1250 	dp->di_prev = dcwd;
1251 	dp->di_next = dcwd->di_next;
1252 	dcwd->di_next = dp;
1253 	dp->di_next->di_prev = dp;
1254     }
1255     dgetstack();	/* Make $dirstack reflect the current state */
1256 }
1257 
1258 static void
dgetstack(void)1259 dgetstack(void)
1260 {
1261     int i = 0;
1262     Char **dblk, **dbp;
1263     struct directory *dn;
1264 
1265     if (adrof(STRdirstack) == NULL)
1266     	return;
1267 
1268     for (dn = dhead.di_prev; dn != &dhead; dn = dn->di_prev, i++)
1269 	continue;
1270     dbp = dblk = xmalloc((i + 1) * sizeof(Char *));
1271     for (dn = dhead.di_prev; dn != &dhead; dn = dn->di_prev, dbp++)
1272 	 *dbp = Strsave(dn->di_name);
1273     *dbp = NULL;
1274     cleanup_push(dblk, blk_cleanup);
1275     setq(STRdirstack, dblk, &shvhed, VAR_READWRITE);
1276     cleanup_ignore(dblk);
1277     cleanup_until(dblk);
1278 }
1279 
1280 /*
1281  * getstakd - added by kfk 17 Jan 1984
1282  * Support routine for the stack hack.  Finds nth directory in
1283  * the directory stack, or finds last directory in stack.
1284  */
1285 const Char *
getstakd(int cnt)1286 getstakd(int cnt)
1287 {
1288     struct directory *dp;
1289 
1290     dp = dcwd;
1291     if (cnt < 0) {		/* < 0 ==> last dir requested. */
1292 	dp = dp->di_next;
1293 	if (dp == &dhead)
1294 	    dp = dp->di_next;
1295     }
1296     else {
1297 	while (cnt-- > 0) {
1298 	    dp = dp->di_prev;
1299 	    if (dp == &dhead)
1300 		dp = dp->di_prev;
1301 	    if (dp == dcwd)
1302 		return NULL;
1303 	}
1304     }
1305     return dp->di_name;
1306 }
1307 
1308 /*
1309  * Karl Kleinpaste - 10 Feb 1984
1310  * Added dextract(), which is used in pushd +n.
1311  * Instead of just rotating the entire stack around, dextract()
1312  * lets the user have the nth dir extracted from its current
1313  * position, and pushes it onto the top.
1314  */
1315 static void
dextract(struct directory * dp)1316 dextract(struct directory *dp)
1317 {
1318     if (dp == dcwd)
1319 	return;
1320     dp->di_next->di_prev = dp->di_prev;
1321     dp->di_prev->di_next = dp->di_next;
1322     dp->di_next = dcwd->di_next;
1323     dp->di_prev = dcwd;
1324     dp->di_next->di_prev = dp;
1325     dcwd->di_next = dp;
1326 }
1327 
1328 static void
bequiet_cleanup(void * dummy)1329 bequiet_cleanup(void *dummy)
1330 {
1331     USE(dummy);
1332     bequiet = 0;
1333 }
1334 
1335 void
loaddirs(Char * fname)1336 loaddirs(Char *fname)
1337 {
1338     static Char *loaddirs_cmd[] = { STRsource, NULL, NULL };
1339 
1340     bequiet = 1;
1341     cleanup_push(&bequiet, bequiet_cleanup);
1342     if (fname)
1343 	loaddirs_cmd[1] = fname;
1344     else if ((fname = varval(STRdirsfile)) != STRNULL)
1345 	loaddirs_cmd[1] = fname;
1346     else
1347 	loaddirs_cmd[1] = STRtildotdirs;
1348     dosource(loaddirs_cmd, NULL);
1349     cleanup_until(&bequiet);
1350 }
1351 
1352 /*
1353  * create a file called ~/.cshdirs which has a sequence
1354  * of pushd commands which will restore the dir stack to
1355  * its state before exit/logout. remember that the order
1356  * is reversed in the file because we are pushing.
1357  * -strike
1358  */
1359 void
recdirs(Char * fname,int def)1360 recdirs(Char *fname, int def)
1361 {
1362     int     fp, ftmp, oldidfds, ophup_disabled;
1363     int     cdflag = 0;
1364     struct directory *dp;
1365     unsigned int    num;
1366     Char   *snum;
1367     struct Strbuf qname = Strbuf_INIT;
1368 
1369     if (fname == NULL && !def)
1370 	return;
1371 
1372     ophup_disabled = phup_disabled;
1373     phup_disabled = 1;
1374     if (fname == NULL) {
1375 	if ((fname = varval(STRdirsfile)) == STRNULL)
1376 	    fname = Strspl(varval(STRhome), &STRtildotdirs[1]);
1377 	else
1378 	    fname = Strsave(fname);
1379     }
1380     else
1381 	fname = globone(fname, G_ERROR);
1382     cleanup_push(fname, xfree);
1383 
1384     if ((fp = xcreat(short2str(fname), 0600)) == -1) {
1385 	cleanup_until(fname);
1386 	phup_disabled = ophup_disabled;
1387 	return;
1388     }
1389 
1390     if ((snum = varval(STRsavedirs)) == STRNULL || snum[0] == '\0')
1391 	num = (unsigned int) ~0;
1392     else
1393 	num = (unsigned int) atoi(short2str(snum));
1394 
1395     oldidfds = didfds;
1396     didfds = 0;
1397     ftmp = SHOUT;
1398     SHOUT = fp;
1399 
1400     cleanup_push(&qname, Strbuf_cleanup);
1401     dp = dcwd->di_next;
1402     do {
1403 	if (dp == &dhead)
1404 	    continue;
1405 
1406 	if (cdflag == 0) {
1407 	    cdflag = 1;
1408 	    xprintf("cd %S\n", quote_meta(&qname, dp->di_name));
1409 	}
1410 	else
1411 	    xprintf("pushd %S\n", quote_meta(&qname, dp->di_name));
1412 
1413 	if (num-- == 0)
1414 	    break;
1415 
1416     } while ((dp = dp->di_next) != dcwd->di_next);
1417 
1418     xclose(fp);
1419     SHOUT = ftmp;
1420     didfds = oldidfds;
1421     cleanup_until(fname);
1422     phup_disabled = ophup_disabled;
1423 }
1424