xref: /openbsd/gnu/usr.bin/perl/dist/PathTools/Cwd.xs (revision 4bdff4be)
1 /*
2  * ex: set ts=8 sts=4 sw=4 et:
3  */
4 
5 #define PERL_NO_GET_CONTEXT
6 
7 #include "EXTERN.h"
8 #include "perl.h"
9 #include "XSUB.h"
10 #ifndef NO_PPPORT_H
11 #  define NEED_croak_xs_usage
12 #  define NEED_sv_2pv_flags
13 #  define NEED_my_strlcpy
14 #  define NEED_my_strlcat
15 #  include "ppport.h"
16 #endif
17 
18 #if defined(HAS_READLINK) && !defined(PerlLIO_readlink)
19 #define PerlLIO_readlink readlink
20 #endif
21 
22 #ifdef I_UNISTD
23 #   include <unistd.h>
24 #endif
25 
26 /* For special handling of os390 sysplexed systems */
27 #define SYSNAME "$SYSNAME"
28 #define SYSNAME_LEN (sizeof(SYSNAME) - 1)
29 
30 /* The realpath() implementation from OpenBSD 3.9 to 4.2 (realpath.c 1.13)
31  * Renamed here to bsd_realpath() to avoid library conflicts.
32  */
33 
34 /* See
35  * http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/2004-11/msg00979.html
36  * for the details of why the BSD license is compatible with the
37  * AL/GPL standard perl license.
38  */
39 
40 /*
41  * Copyright (c) 2003 Constantin S. Svintsoff <kostik@iclub.nsu.ru>
42  *
43  * Redistribution and use in source and binary forms, with or without
44  * modification, are permitted provided that the following conditions
45  * are met:
46  * 1. Redistributions of source code must retain the above copyright
47  *    notice, this list of conditions and the following disclaimer.
48  * 2. Redistributions in binary form must reproduce the above copyright
49  *    notice, this list of conditions and the following disclaimer in the
50  *    documentation and/or other materials provided with the distribution.
51  * 3. The names of the authors may not be used to endorse or promote
52  *    products derived from this software without specific prior written
53  *    permission.
54  *
55  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS" AND
56  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
57  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
58  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
59  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
60  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
61  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
62  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
63  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
64  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
65  * SUCH DAMAGE.
66  */
67 
68 /* OpenBSD system #includes removed since the Perl ones should do. --jhi */
69 
70 #ifndef MAXSYMLINKS
71 #define MAXSYMLINKS 8
72 #endif
73 
74 #ifndef VMS
75 /*
76  * char *realpath(const char *path, char resolved[MAXPATHLEN]);
77  *
78  * Find the real name of path, by removing all ".", ".." and symlink
79  * components.  Returns (resolved) on success, or (NULL) on failure,
80  * in which case the path which caused trouble is left in (resolved).
81  */
82 static
83 char *
84 bsd_realpath(const char *path, char resolved[MAXPATHLEN])
85 {
86 	char *p, *q, *s;
87 	size_t remaining_len, resolved_len;
88 	unsigned symlinks;
89 	int serrno;
90 	char remaining[MAXPATHLEN], next_token[MAXPATHLEN];
91 #ifdef PERL_IMPLICIT_SYS
92         dTHX;
93 #endif
94 
95 	serrno = errno;
96 	symlinks = 0;
97 	if (path[0] == '/') {
98             resolved[0] = '/';
99             resolved[1] = '\0';
100             if (path[1] == '\0')
101                     return (resolved);
102             resolved_len = 1;
103             remaining_len = my_strlcpy(remaining, path + 1, sizeof(remaining));
104 	} else {
105             if (getcwd(resolved, MAXPATHLEN) == NULL) {
106                 my_strlcpy(resolved, ".", MAXPATHLEN);
107                 return (NULL);
108             }
109             resolved_len = strlen(resolved);
110             remaining_len = my_strlcpy(remaining, path, sizeof(remaining));
111 	}
112 	if (remaining_len >= sizeof(remaining) || resolved_len >= MAXPATHLEN) {
113             errno = ENAMETOOLONG;
114             return (NULL);
115 	}
116 
117 	/*
118 	 * Iterate over path components in 'remaining'.
119 	 */
120 	while (remaining_len != 0) {
121 
122             /*
123              * Extract the next path component and adjust 'remaining'
124              * and its length.
125              */
126 
127             p = strchr(remaining, '/');
128             s = p ? p : remaining + remaining_len;
129 
130             if ((STRLEN)(s - remaining) >= (STRLEN)sizeof(next_token)) {
131                 errno = ENAMETOOLONG;
132                 return (NULL);
133             }
134             memcpy(next_token, remaining, s - remaining);
135             next_token[s - remaining] = '\0';
136 
137             /* shift first component off front of path, including '/' */
138             if (p) {
139                 s++; /* skip '/' */
140                 remaining_len -= s - remaining;
141                 /* the +1 includes the trailing '\0' */
142                 memmove(remaining, s, remaining_len + 1);
143             }
144             else
145                 remaining_len = 0;
146 
147             if (resolved[resolved_len - 1] != '/') {
148                 if (resolved_len + 1 >= MAXPATHLEN) {
149                     errno = ENAMETOOLONG;
150                     return (NULL);
151                 }
152                 resolved[resolved_len++] = '/';
153                 resolved[resolved_len] = '\0';
154             }
155             if (next_token[0] == '\0')
156                 continue;
157             else if (strEQ(next_token, "."))
158                 continue;
159             else if (strEQ(next_token, "..")) {
160                 /*
161                  * Strip the last path component except when we have
162                  * single "/"
163                  */
164                 if (resolved_len > 1) {
165                     resolved[resolved_len - 1] = '\0';
166                     q = strrchr(resolved, '/') + 1;
167                     *q = '\0';
168                     resolved_len = q - resolved;
169                 }
170                 continue;
171             }
172 
173             /*
174              * Append the next path component and lstat() it. If
175              * lstat() fails we still can return successfully if
176              * there are no more path components left.
177              */
178             resolved_len = my_strlcat(resolved, next_token, MAXPATHLEN);
179             if (resolved_len >= MAXPATHLEN) {
180                 errno = ENAMETOOLONG;
181                 return (NULL);
182             }
183 #if defined(HAS_LSTAT) && defined(HAS_READLINK) && defined(HAS_SYMLINK)
184             {
185                 Stat_t sb;
186                 if (PerlLIO_lstat(resolved, &sb) != 0) {
187                     if (errno == ENOENT && p == NULL) {
188                         errno = serrno;
189                         return (resolved);
190                     }
191                     return (NULL);
192                 }
193                 if (S_ISLNK(sb.st_mode)) {
194                     int slen;
195                     char symlink[MAXPATHLEN];
196 
197                     if (symlinks++ > MAXSYMLINKS) {
198                         errno = ELOOP;
199                         return (NULL);
200                     }
201                     slen = PerlLIO_readlink(resolved, symlink, sizeof(symlink) - 1);
202                     if (slen < 0)
203                         return (NULL);
204                     symlink[slen] = '\0';
205 #  ifdef EBCDIC /* XXX Probably this should be only os390 */
206                     /* Replace all instances of $SYSNAME/foo simply by /foo */
207                     if (slen > SYSNAME_LEN + strlen(next_token)
208                         && strnEQ(symlink, SYSNAME, SYSNAME_LEN)
209                         && *(symlink + SYSNAME_LEN) == '/'
210                         && strEQ(symlink + SYSNAME_LEN + 1, next_token))
211                     {
212                         goto not_symlink;
213                     }
214 #  endif
215                     if (symlink[0] == '/') {
216                         resolved[1] = 0;
217                         resolved_len = 1;
218                     } else if (resolved_len > 1) {
219                         /* Strip the last path component. */
220                         resolved[resolved_len - 1] = '\0';
221                         q = strrchr(resolved, '/') + 1;
222                         *q = '\0';
223                         resolved_len = q - resolved;
224                     }
225 
226                     /*
227                      * If there are any path components left, then
228                      * append them to symlink. The result is placed
229                      * in 'remaining'.
230                      */
231                     if (p != NULL) {
232                         if (symlink[slen - 1] != '/') {
233                             if ((STRLEN)(slen + 1) >= (STRLEN)sizeof(symlink)) {
234                                 errno = ENAMETOOLONG;
235                                 return (NULL);
236                             }
237                             symlink[slen] = '/';
238                             symlink[slen + 1] = 0;
239                         }
240                         remaining_len = my_strlcat(symlink, remaining, sizeof(symlink));
241                         if (remaining_len >= sizeof(remaining)) {
242                             errno = ENAMETOOLONG;
243                             return (NULL);
244                         }
245                     }
246                     remaining_len = my_strlcpy(remaining, symlink, sizeof(remaining));
247                 }
248 #  ifdef EBCDIC
249               not_symlink: ;
250 #  endif
251             }
252 #endif
253 	}
254 
255 	/*
256 	 * Remove trailing slash except when the resolved pathname
257 	 * is a single "/".
258 	 */
259 	if (resolved_len > 1 && resolved[resolved_len - 1] == '/')
260             resolved[resolved_len - 1] = '\0';
261 	return (resolved);
262 }
263 #endif
264 
265 #ifndef SV_CWD_RETURN_UNDEF
266 #define SV_CWD_RETURN_UNDEF \
267 sv_setsv(sv, &PL_sv_undef); \
268 return FALSE
269 #endif
270 
271 #ifndef OPpENTERSUB_HASTARG
272 #define OPpENTERSUB_HASTARG     32      /* Called from OP tree. */
273 #endif
274 
275 #ifndef dXSTARG
276 #define dXSTARG SV * targ = ((PL_op->op_private & OPpENTERSUB_HASTARG) \
277                              ? PAD_SV(PL_op->op_targ) : sv_newmortal())
278 #endif
279 
280 #ifndef XSprePUSH
281 #define XSprePUSH (sp = PL_stack_base + ax - 1)
282 #endif
283 
284 #ifndef SV_CWD_ISDOT
285 #define SV_CWD_ISDOT(dp) \
286     (dp->d_name[0] == '.' && (dp->d_name[1] == '\0' || \
287         (dp->d_name[1] == '.' && dp->d_name[2] == '\0')))
288 #endif
289 
290 #ifndef getcwd_sv
291 /* Taken from perl 5.8's util.c */
292 #define getcwd_sv(a) Perl_getcwd_sv(aTHX_ a)
293 int Perl_getcwd_sv(pTHX_ SV *sv)
294 {
295 #ifndef PERL_MICRO
296 
297     SvTAINTED_on(sv);
298 
299 #ifdef HAS_GETCWD
300     {
301 	char buf[MAXPATHLEN];
302 
303 	/* Some getcwd()s automatically allocate a buffer of the given
304 	 * size from the heap if they are given a NULL buffer pointer.
305 	 * The problem is that this behaviour is not portable. */
306 	if (getcwd(buf, sizeof(buf) - 1)) {
307 	    STRLEN len = strlen(buf);
308 	    sv_setpvn(sv, buf, len);
309 	    return TRUE;
310 	}
311 	else {
312 	    sv_setsv(sv, &PL_sv_undef);
313 	    return FALSE;
314 	}
315     }
316 
317 #else
318   {
319     Stat_t statbuf;
320     int orig_cdev, orig_cino, cdev, cino, odev, oino, tdev, tino;
321     int namelen, pathlen=0;
322     DIR *dir;
323     Direntry_t *dp;
324 
325     (void)SvUPGRADE(sv, SVt_PV);
326 
327     if (PerlLIO_lstat(".", &statbuf) < 0) {
328 	SV_CWD_RETURN_UNDEF;
329     }
330 
331     orig_cdev = statbuf.st_dev;
332     orig_cino = statbuf.st_ino;
333     cdev = orig_cdev;
334     cino = orig_cino;
335 
336     for (;;) {
337 	odev = cdev;
338 	oino = cino;
339 
340 	if (PerlDir_chdir("..") < 0) {
341 	    SV_CWD_RETURN_UNDEF;
342 	}
343 	if (PerlLIO_stat(".", &statbuf) < 0) {
344 	    SV_CWD_RETURN_UNDEF;
345 	}
346 
347 	cdev = statbuf.st_dev;
348 	cino = statbuf.st_ino;
349 
350 	if (odev == cdev && oino == cino) {
351 	    break;
352 	}
353 	if (!(dir = PerlDir_open("."))) {
354 	    SV_CWD_RETURN_UNDEF;
355 	}
356 
357 	while ((dp = PerlDir_read(dir)) != NULL) {
358 #ifdef DIRNAMLEN
359 	    namelen = dp->d_namlen;
360 #else
361 	    namelen = strlen(dp->d_name);
362 #endif
363 	    /* skip . and .. */
364 	    if (SV_CWD_ISDOT(dp)) {
365 		continue;
366 	    }
367 
368 	    if (PerlLIO_lstat(dp->d_name, &statbuf) < 0) {
369 		SV_CWD_RETURN_UNDEF;
370 	    }
371 
372 	    tdev = statbuf.st_dev;
373 	    tino = statbuf.st_ino;
374 	    if (tino == oino && tdev == odev) {
375 		break;
376 	    }
377 	}
378 
379 	if (!dp) {
380 	    SV_CWD_RETURN_UNDEF;
381 	}
382 
383 	if (pathlen + namelen + 1 >= MAXPATHLEN) {
384 	    SV_CWD_RETURN_UNDEF;
385 	}
386 
387 	SvGROW(sv, pathlen + namelen + 1);
388 
389 	if (pathlen) {
390 	    /* shift down */
391 	    Move(SvPVX(sv), SvPVX(sv) + namelen + 1, pathlen, char);
392 	}
393 
394 	/* prepend current directory to the front */
395 	*SvPVX(sv) = '/';
396 	Move(dp->d_name, SvPVX(sv)+1, namelen, char);
397 	pathlen += (namelen + 1);
398 
399 #ifdef VOID_CLOSEDIR
400 	PerlDir_close(dir);
401 #else
402 	if (PerlDir_close(dir) < 0) {
403 	    SV_CWD_RETURN_UNDEF;
404 	}
405 #endif
406     }
407 
408     if (pathlen) {
409 	SvCUR_set(sv, pathlen);
410 	*SvEND(sv) = '\0';
411 	SvPOK_only(sv);
412 
413 	if (PerlDir_chdir(SvPVX(sv)) < 0) {
414 	    SV_CWD_RETURN_UNDEF;
415 	}
416     }
417     if (PerlLIO_stat(".", &statbuf) < 0) {
418 	SV_CWD_RETURN_UNDEF;
419     }
420 
421     cdev = statbuf.st_dev;
422     cino = statbuf.st_ino;
423 
424     if (cdev != orig_cdev || cino != orig_cino) {
425 	Perl_croak(aTHX_ "Unstable directory path, "
426 		   "current directory changed unexpectedly");
427     }
428 
429     return TRUE;
430   }
431 #endif
432 
433 #else
434     return FALSE;
435 #endif
436 }
437 
438 #endif
439 
440 #if defined(START_MY_CXT) && defined(MY_CXT_CLONE)
441 # define USE_MY_CXT 1
442 #else
443 # define USE_MY_CXT 0
444 #endif
445 
446 #if USE_MY_CXT
447 # define MY_CXT_KEY "Cwd::_guts" XS_VERSION
448 typedef struct {
449     SV *empty_string_sv, *slash_string_sv;
450 } my_cxt_t;
451 START_MY_CXT
452 # define dUSE_MY_CXT dMY_CXT
453 # define EMPTY_STRING_SV MY_CXT.empty_string_sv
454 # define SLASH_STRING_SV MY_CXT.slash_string_sv
455 # define POPULATE_MY_CXT do { \
456 	MY_CXT.empty_string_sv = newSVpvs(""); \
457 	MY_CXT.slash_string_sv = newSVpvs("/"); \
458     } while(0)
459 #else
460 # define dUSE_MY_CXT dNOOP
461 # define EMPTY_STRING_SV sv_2mortal(newSVpvs(""))
462 # define SLASH_STRING_SV sv_2mortal(newSVpvs("/"))
463 #endif
464 
465 #define invocant_is_unix(i) THX_invocant_is_unix(aTHX_ i)
466 static
467 bool
468 THX_invocant_is_unix(pTHX_ SV *invocant)
469 {
470     /*
471      * This is used to enable optimisations that avoid method calls
472      * by knowing how they would resolve.  False negatives, disabling
473      * the optimisation where it would actually behave correctly, are
474      * acceptable.
475      */
476     return SvPOK(invocant) && SvCUR(invocant) == 16 &&
477 	!memcmp(SvPVX(invocant), "File::Spec::Unix", 16);
478 }
479 
480 #define unix_canonpath(p) THX_unix_canonpath(aTHX_ p)
481 static
482 SV *
483 THX_unix_canonpath(pTHX_ SV *path)
484 {
485     SV *retval;
486     char const *p, *pe, *q;
487     STRLEN l;
488     char *o;
489     STRLEN plen;
490     SvGETMAGIC(path);
491     if(!SvOK(path)) return &PL_sv_undef;
492     p = SvPV_nomg(path, plen);
493     if(plen == 0) return newSVpvs("");
494     pe = p + plen;
495     retval = newSV(plen);
496 #ifdef SvUTF8
497     if(SvUTF8(path)) SvUTF8_on(retval);
498 #endif
499     o = SvPVX(retval);
500     if(DOUBLE_SLASHES_SPECIAL && p[0] == '/' && p[1] == '/' && p[2] != '/') {
501 	q = (const char *) memchr(p+2, '/', pe-(p+2));
502 	if(!q) q = pe;
503 	l = q - p;
504 	memcpy(o, p, l);
505 	p = q;
506 	o += l;
507     }
508     /*
509      * The transformations performed here are:
510      *   . squeeze multiple slashes
511      *   . eliminate "." segments, except one if that's all there is
512      *   . eliminate leading ".." segments
513      *   . eliminate trailing slash, unless it's all there is
514      */
515     if(p[0] == '/') {
516 	*o++ = '/';
517 	while(1) {
518 	    do { p++; } while(p[0] == '/');
519 	    if(p[0] == '.' && p[1] == '.' && (p+2 == pe || p[2] == '/')) {
520 		p++;
521 		/* advance past second "." next time round loop */
522 	    } else if(p[0] == '.' && (p+1 == pe || p[1] == '/')) {
523 		/* advance past "." next time round loop */
524 	    } else {
525 		break;
526 	    }
527 	}
528     } else if(p[0] == '.' && p[1] == '/') {
529 	do {
530 	    p++;
531 	    do { p++; } while(p[0] == '/');
532 	} while(p[0] == '.' && p[1] == '/');
533 	if(p == pe) *o++ = '.';
534     }
535     if(p == pe) goto end;
536     while(1) {
537 	q = (const char *) memchr(p, '/', pe-p);
538 	if(!q) q = pe;
539 	l = q - p;
540 	memcpy(o, p, l);
541 	p = q;
542 	o += l;
543 	if(p == pe) goto end;
544 	while(1) {
545 	    do { p++; } while(p[0] == '/');
546 	    if(p == pe) goto end;
547 	    if(p[0] != '.') break;
548 	    if(p+1 == pe) goto end;
549 	    if(p[1] != '/') break;
550 	    p++;
551 	}
552 	*o++ = '/';
553     }
554     end: ;
555     *o = 0;
556     SvPOK_on(retval);
557     SvCUR_set(retval, o - SvPVX(retval));
558     SvTAINT(retval);
559     return retval;
560 }
561 
562 MODULE = Cwd		PACKAGE = Cwd
563 
564 PROTOTYPES: DISABLE
565 
566 BOOT:
567 #if USE_MY_CXT
568 {
569     MY_CXT_INIT;
570     POPULATE_MY_CXT;
571 }
572 #endif
573 
574 #if USE_MY_CXT
575 
576 void
577 CLONE(...)
578 CODE:
579 	PERL_UNUSED_VAR(items);
580 	{ MY_CXT_CLONE; POPULATE_MY_CXT; }
581 
582 #endif
583 
584 void
585 getcwd(...)
586 ALIAS:
587     fastcwd=1
588 PPCODE:
589 {
590     dXSTARG;
591     /* fastcwd takes zero parameters:  */
592     if (ix == 1 && items != 0)
593 	croak_xs_usage(cv,  "");
594     getcwd_sv(TARG);
595     XSprePUSH; PUSHTARG;
596     SvTAINTED_on(TARG);
597 }
598 
599 void
600 abs_path(pathsv=Nullsv)
601     SV *pathsv
602 PPCODE:
603 {
604     dXSTARG;
605     char *const path = pathsv ? SvPV_nolen(pathsv) : (char *)".";
606     char buf[MAXPATHLEN];
607 
608     if (
609 #ifdef VMS
610 	Perl_rmsexpand(aTHX_ path, buf, NULL, 0)
611 #else
612 	bsd_realpath(path, buf)
613 #endif
614     ) {
615 	sv_setpv_mg(TARG, buf);
616         SvPOK_only(TARG);
617 	SvTAINTED_on(TARG);
618     }
619     else
620         sv_setsv(TARG, &PL_sv_undef);
621 
622     XSprePUSH; PUSHs(TARG);
623     SvTAINTED_on(TARG);
624 }
625 
626 #if defined(WIN32) && !defined(UNDER_CE)
627 
628 void
629 getdcwd(...)
630 PROTOTYPE: ENABLE
631 PPCODE:
632 {
633     dXSTARG;
634     int drive;
635     char *dir;
636 
637     /* Drive 0 is the current drive, 1 is A:, 2 is B:, 3 is C: and so on. */
638     if ( items == 0 ||
639         (items == 1 && (!SvOK(ST(0)) || (SvPOK(ST(0)) && !SvCUR(ST(0))))))
640         drive = 0;
641     else if (items == 1 && SvPOK(ST(0)) && SvCUR(ST(0)) &&
642              isALPHA(SvPVX(ST(0))[0]))
643         drive = toUPPER(SvPVX(ST(0))[0]) - 'A' + 1;
644     else
645         croak("Usage: getdcwd(DRIVE)");
646 
647     New(0,dir,MAXPATHLEN,char);
648     if (_getdcwd(drive, dir, MAXPATHLEN)) {
649         sv_setpv_mg(TARG, dir);
650         SvPOK_only(TARG);
651     }
652     else
653         sv_setsv(TARG, &PL_sv_undef);
654 
655     Safefree(dir);
656 
657     XSprePUSH; PUSHs(TARG);
658     SvTAINTED_on(TARG);
659 }
660 
661 #endif
662 
663 MODULE = Cwd		PACKAGE = File::Spec::Unix
664 
665 SV *
666 canonpath(SV *self, SV *path = &PL_sv_undef, ...)
667 CODE:
668     PERL_UNUSED_VAR(self);
669     RETVAL = unix_canonpath(path);
670 OUTPUT:
671     RETVAL
672 
673 SV *
674 _fn_canonpath(SV *path = &PL_sv_undef, ...)
675 CODE:
676     RETVAL = unix_canonpath(path);
677 OUTPUT:
678     RETVAL
679 
680 SV *
681 catdir(SV *self, ...)
682 PREINIT:
683     dUSE_MY_CXT;
684     SV *joined;
685 CODE:
686     EXTEND(SP, items+1);
687     ST(items) = EMPTY_STRING_SV;
688     joined = sv_newmortal();
689     do_join(joined, SLASH_STRING_SV, &ST(0), &ST(items));
690     if(invocant_is_unix(self)) {
691 	RETVAL = unix_canonpath(joined);
692     } else {
693 	ENTER;
694 	PUSHMARK(SP);
695 	EXTEND(SP, 2);
696 	PUSHs(self);
697 	PUSHs(joined);
698 	PUTBACK;
699 	call_method("canonpath", G_SCALAR);
700 	SPAGAIN;
701 	RETVAL = POPs;
702 	LEAVE;
703 	SvREFCNT_inc(RETVAL);
704     }
705 OUTPUT:
706     RETVAL
707 
708 SV *
709 _fn_catdir(...)
710 PREINIT:
711     dUSE_MY_CXT;
712     SV *joined;
713 CODE:
714     EXTEND(SP, items+1);
715     ST(items) = EMPTY_STRING_SV;
716     joined = sv_newmortal();
717     do_join(joined, SLASH_STRING_SV, &ST(-1), &ST(items));
718     RETVAL = unix_canonpath(joined);
719 OUTPUT:
720     RETVAL
721 
722 SV *
723 catfile(SV *self, ...)
724 PREINIT:
725     dUSE_MY_CXT;
726 CODE:
727     if(invocant_is_unix(self)) {
728 	if(items == 1) {
729 	    RETVAL = &PL_sv_undef;
730 	} else {
731 	    SV *file = unix_canonpath(ST(items-1));
732 	    if(items == 2) {
733 		RETVAL = file;
734 	    } else {
735 		SV *dir = sv_newmortal();
736 		sv_2mortal(file);
737 		ST(items-1) = EMPTY_STRING_SV;
738 		do_join(dir, SLASH_STRING_SV, &ST(0), &ST(items-1));
739 		RETVAL = unix_canonpath(dir);
740 		if(SvCUR(RETVAL) == 0 || SvPVX(RETVAL)[SvCUR(RETVAL)-1] != '/')
741 		    sv_catsv(RETVAL, SLASH_STRING_SV);
742 		sv_catsv(RETVAL, file);
743 	    }
744 	}
745     } else {
746 	SV *file, *dir;
747 	ENTER;
748 	PUSHMARK(SP);
749 	EXTEND(SP, 2);
750 	PUSHs(self);
751 	PUSHs(items == 1 ? &PL_sv_undef : ST(items-1));
752 	PUTBACK;
753 	call_method("canonpath", G_SCALAR);
754 	SPAGAIN;
755 	file = POPs;
756 	LEAVE;
757 	if(items <= 2) {
758 	    RETVAL = SvREFCNT_inc(file);
759 	} else {
760 	    char const *pv;
761 	    STRLEN len;
762 	    bool need_slash;
763 	    SP--;
764 	    ENTER;
765 	    PUSHMARK(&ST(-1));
766 	    PUTBACK;
767 	    call_method("catdir", G_SCALAR);
768 	    SPAGAIN;
769 	    dir = POPs;
770 	    LEAVE;
771 	    pv = SvPV(dir, len);
772 	    need_slash = len == 0 || pv[len-1] != '/';
773 	    RETVAL = newSVsv(dir);
774 	    if(need_slash) sv_catsv(RETVAL, SLASH_STRING_SV);
775 	    sv_catsv(RETVAL, file);
776 	}
777     }
778 OUTPUT:
779     RETVAL
780 
781 SV *
782 _fn_catfile(...)
783 PREINIT:
784     dUSE_MY_CXT;
785 CODE:
786     if(items == 0) {
787 	RETVAL = &PL_sv_undef;
788     } else {
789 	SV *file = unix_canonpath(ST(items-1));
790 	if(items == 1) {
791 	    RETVAL = file;
792 	} else {
793 	    SV *dir = sv_newmortal();
794 	    sv_2mortal(file);
795 	    ST(items-1) = EMPTY_STRING_SV;
796 	    do_join(dir, SLASH_STRING_SV, &ST(-1), &ST(items-1));
797 	    RETVAL = unix_canonpath(dir);
798 	    if(SvCUR(RETVAL) == 0 || SvPVX(RETVAL)[SvCUR(RETVAL)-1] != '/')
799 		sv_catsv(RETVAL, SLASH_STRING_SV);
800 	    sv_catsv(RETVAL, file);
801 	}
802     }
803 OUTPUT:
804     RETVAL
805