remove realpath() compat replacement

We shipped a BSD implementation of realpath() because sftp-server
depended on its behaviour.

OpenBSD is now moving to a more strictly POSIX-compliant realpath(2),
so sftp-server now unconditionally requires its own BSD-style realpath
implementation. As such, there is no need to carry another independant
implementation in openbsd-compat.

ok dtucker@

7 files changed, 3 insertions, 277 deletions

diff --git a/.depend b/.depend
index 6d5934cf9..54e889523 100644
--- a/.depend
+++ b/.depend
@@ -63,7 +63,7 @@ kex.o: includes.h config.h defines.h platform.h openbsd-compat/openbsd-compat.h
 kex.o: misc.h monitor.h ssherr.h sshbuf.h digest.h
 kexc25519.o: includes.h config.h defines.h platform.h openbsd-compat/openbsd-compat.h openbsd-compat/base64.h openbsd-compat/sigact.h openbsd-compat/readpassphrase.h openbsd-compat/vis.h openbsd-compat/getrrsetbyname.h openbsd-compat/sha1.h openbsd-compat/sha2.h openbsd-compat/rmd160.h openbsd-compat/md5.h openbsd-compat/blf.h openbsd-compat/getopt.h openbsd-compat/bsd-misc.h openbsd-compat/bsd-setres_id.h openbsd-compat/bsd-signal.h openbsd-compat/bsd-statvfs.h openbsd-compat/bsd-waitpid.h openbsd-compat/bsd-poll.h openbsd-compat/fake-rfc2553.h openbsd-compat/bsd-cygwin_util.h openbsd-compat/port-aix.h openbsd-compat/port-irix.h openbsd-compat/port-linux.h openbsd-compat/port-solaris.h openbsd-compat/port-net.h openbsd-compat/port-uw.h openbsd-compat/bsd-nextstep.h entropy.h sshkey.h kex.h mac.h crypto_api.h sshbuf.h digest.h ssherr.h ssh2.h
 kexdh.o: includes.h config.h defines.h platform.h openbsd-compat/openbsd-compat.h openbsd-compat/base64.h openbsd-compat/sigact.h openbsd-compat/readpassphrase.h openbsd-compat/vis.h openbsd-compat/getrrsetbyname.h openbsd-compat/sha1.h openbsd-compat/sha2.h openbsd-compat/rmd160.h openbsd-compat/md5.h openbsd-compat/blf.h openbsd-compat/getopt.h openbsd-compat/bsd-misc.h openbsd-compat/bsd-setres_id.h openbsd-compat/bsd-signal.h openbsd-compat/bsd-statvfs.h openbsd-compat/bsd-waitpid.h openbsd-compat/bsd-poll.h openbsd-compat/fake-rfc2553.h openbsd-compat/bsd-cygwin_util.h openbsd-compat/port-aix.h openbsd-compat/port-irix.h openbsd-compat/port-linux.h openbsd-compat/port-solaris.h openbsd-compat/port-net.h openbsd-compat/port-uw.h openbsd-compat/bsd-nextstep.h entropy.h
-kexecdh.o: includes.h config.h defines.h platform.h openbsd-compat/openbsd-compat.h openbsd-compat/base64.h openbsd-compat/sigact.h openbsd-compat/readpassphrase.h openbsd-compat/vis.h openbsd-compat/getrrsetbyname.h openbsd-compat/sha1.h openbsd-compat/sha2.h openbsd-compat/rmd160.h openbsd-compat/md5.h openbsd-compat/blf.h openbsd-compat/getopt.h openbsd-compat/bsd-misc.h openbsd-compat/bsd-setres_id.h openbsd-compat/bsd-signal.h openbsd-compat/bsd-statvfs.h openbsd-compat/bsd-waitpid.h openbsd-compat/bsd-poll.h openbsd-compat/fake-rfc2553.h openbsd-compat/bsd-cygwin_util.h openbsd-compat/port-aix.h openbsd-compat/port-irix.h openbsd-compat/port-linux.h openbsd-compat/port-solaris.h openbsd-compat/port-net.h openbsd-compat/port-uw.h openbsd-compat/bsd-nextstep.h entropy.h
+kexecdh.o: includes.h config.h defines.h platform.h openbsd-compat/openbsd-compat.h openbsd-compat/base64.h openbsd-compat/sigact.h openbsd-compat/readpassphrase.h openbsd-compat/vis.h openbsd-compat/getrrsetbyname.h openbsd-compat/sha1.h openbsd-compat/sha2.h openbsd-compat/rmd160.h openbsd-compat/md5.h openbsd-compat/blf.h openbsd-compat/getopt.h openbsd-compat/bsd-misc.h openbsd-compat/bsd-setres_id.h openbsd-compat/bsd-signal.h openbsd-compat/bsd-statvfs.h openbsd-compat/bsd-waitpid.h openbsd-compat/bsd-poll.h openbsd-compat/fake-rfc2553.h openbsd-compat/bsd-cygwin_util.h openbsd-compat/port-aix.h openbsd-compat/port-irix.h openbsd-compat/port-linux.h openbsd-compat/port-solaris.h openbsd-compat/port-net.h openbsd-compat/port-uw.h openbsd-compat/bsd-nextstep.h entropy.h sshkey.h kex.h mac.h crypto_api.h ssherr.h
 kexgen.o: includes.h config.h defines.h platform.h openbsd-compat/openbsd-compat.h openbsd-compat/base64.h openbsd-compat/sigact.h openbsd-compat/readpassphrase.h openbsd-compat/vis.h openbsd-compat/getrrsetbyname.h openbsd-compat/sha1.h openbsd-compat/sha2.h openbsd-compat/rmd160.h openbsd-compat/md5.h openbsd-compat/blf.h openbsd-compat/getopt.h openbsd-compat/bsd-misc.h openbsd-compat/bsd-setres_id.h openbsd-compat/bsd-signal.h openbsd-compat/bsd-statvfs.h openbsd-compat/bsd-waitpid.h openbsd-compat/bsd-poll.h openbsd-compat/fake-rfc2553.h openbsd-compat/bsd-cygwin_util.h openbsd-compat/port-aix.h openbsd-compat/port-irix.h openbsd-compat/port-linux.h openbsd-compat/port-solaris.h openbsd-compat/port-net.h openbsd-compat/port-uw.h openbsd-compat/bsd-nextstep.h entropy.h sshkey.h kex.h mac.h crypto_api.h log.h packet.h openbsd-compat/sys-queue.h dispatch.h ssh2.h sshbuf.h digest.h ssherr.h
 kexgex.o: includes.h config.h defines.h platform.h openbsd-compat/openbsd-compat.h openbsd-compat/base64.h openbsd-compat/sigact.h openbsd-compat/readpassphrase.h openbsd-compat/vis.h openbsd-compat/getrrsetbyname.h openbsd-compat/sha1.h openbsd-compat/sha2.h openbsd-compat/rmd160.h openbsd-compat/md5.h openbsd-compat/blf.h openbsd-compat/getopt.h openbsd-compat/bsd-misc.h openbsd-compat/bsd-setres_id.h openbsd-compat/bsd-signal.h openbsd-compat/bsd-statvfs.h openbsd-compat/bsd-waitpid.h openbsd-compat/bsd-poll.h openbsd-compat/fake-rfc2553.h openbsd-compat/bsd-cygwin_util.h openbsd-compat/port-aix.h openbsd-compat/port-irix.h openbsd-compat/port-linux.h openbsd-compat/port-solaris.h openbsd-compat/port-net.h openbsd-compat/port-uw.h openbsd-compat/bsd-nextstep.h entropy.h
 kexgexc.o: includes.h config.h defines.h platform.h openbsd-compat/openbsd-compat.h openbsd-compat/base64.h openbsd-compat/sigact.h openbsd-compat/readpassphrase.h openbsd-compat/vis.h openbsd-compat/getrrsetbyname.h openbsd-compat/sha1.h openbsd-compat/sha2.h openbsd-compat/rmd160.h openbsd-compat/md5.h openbsd-compat/blf.h openbsd-compat/getopt.h openbsd-compat/bsd-misc.h openbsd-compat/bsd-setres_id.h openbsd-compat/bsd-signal.h openbsd-compat/bsd-statvfs.h openbsd-compat/bsd-waitpid.h openbsd-compat/bsd-poll.h openbsd-compat/fake-rfc2553.h openbsd-compat/bsd-cygwin_util.h openbsd-compat/port-aix.h openbsd-compat/port-irix.h openbsd-compat/port-linux.h openbsd-compat/port-solaris.h openbsd-compat/port-net.h openbsd-compat/port-uw.h openbsd-compat/bsd-nextstep.h entropy.h
@@ -151,7 +151,7 @@ sshd.o: includes.h config.h defines.h platform.h openbsd-compat/openbsd-compat.h
 sshd.o: cipher-aesctr.h rijndael.h digest.h sshkey.h kex.h mac.h crypto_api.h myproposal.h authfile.h pathnames.h atomicio.h canohost.h hostfile.h auth.h auth-pam.h audit.h loginrec.h authfd.h msg.h channels.h session.h monitor.h monitor_wrap.h ssh-sandbox.h auth-options.h version.h ssherr.h
 ssherr.o: ssherr.h
 sshkey-xmss.o: includes.h config.h defines.h platform.h openbsd-compat/openbsd-compat.h openbsd-compat/base64.h openbsd-compat/sigact.h openbsd-compat/readpassphrase.h openbsd-compat/vis.h openbsd-compat/getrrsetbyname.h openbsd-compat/sha1.h openbsd-compat/sha2.h openbsd-compat/rmd160.h openbsd-compat/md5.h openbsd-compat/blf.h openbsd-compat/getopt.h openbsd-compat/bsd-misc.h openbsd-compat/bsd-setres_id.h openbsd-compat/bsd-signal.h openbsd-compat/bsd-statvfs.h openbsd-compat/bsd-waitpid.h openbsd-compat/bsd-poll.h openbsd-compat/fake-rfc2553.h openbsd-compat/bsd-cygwin_util.h openbsd-compat/port-aix.h openbsd-compat/port-irix.h openbsd-compat/port-linux.h openbsd-compat/port-solaris.h openbsd-compat/port-net.h openbsd-compat/port-uw.h openbsd-compat/bsd-nextstep.h entropy.h
-sshkey.o: includes.h config.h defines.h platform.h openbsd-compat/openbsd-compat.h openbsd-compat/base64.h openbsd-compat/sigact.h openbsd-compat/readpassphrase.h openbsd-compat/vis.h openbsd-compat/getrrsetbyname.h openbsd-compat/sha1.h openbsd-compat/sha2.h openbsd-compat/rmd160.h openbsd-compat/md5.h openbsd-compat/blf.h openbsd-compat/getopt.h openbsd-compat/bsd-misc.h openbsd-compat/bsd-setres_id.h openbsd-compat/bsd-signal.h openbsd-compat/bsd-statvfs.h openbsd-compat/bsd-waitpid.h openbsd-compat/bsd-poll.h openbsd-compat/fake-rfc2553.h openbsd-compat/bsd-cygwin_util.h openbsd-compat/port-aix.h openbsd-compat/port-irix.h openbsd-compat/port-linux.h openbsd-compat/port-solaris.h openbsd-compat/port-net.h openbsd-compat/port-uw.h openbsd-compat/bsd-nextstep.h entropy.h crypto_api.h ssh2.h ssherr.h misc.h sshbuf.h cipher.h cipher-chachapoly.h chacha.h poly1305.h cipher-aesctr.h rijndael.h digest.h sshkey.h sshkey-xmss.h match.h xmss_fast.h openbsd-compat/openssl-compat.h
+sshkey.o: includes.h config.h defines.h platform.h openbsd-compat/openbsd-compat.h openbsd-compat/base64.h openbsd-compat/sigact.h openbsd-compat/readpassphrase.h openbsd-compat/vis.h openbsd-compat/getrrsetbyname.h openbsd-compat/sha1.h openbsd-compat/sha2.h openbsd-compat/rmd160.h openbsd-compat/md5.h openbsd-compat/blf.h openbsd-compat/getopt.h openbsd-compat/bsd-misc.h openbsd-compat/bsd-setres_id.h openbsd-compat/bsd-signal.h openbsd-compat/bsd-statvfs.h openbsd-compat/bsd-waitpid.h openbsd-compat/bsd-poll.h openbsd-compat/fake-rfc2553.h openbsd-compat/bsd-cygwin_util.h openbsd-compat/port-aix.h openbsd-compat/port-irix.h openbsd-compat/port-linux.h openbsd-compat/port-solaris.h openbsd-compat/port-net.h openbsd-compat/port-uw.h openbsd-compat/bsd-nextstep.h entropy.h crypto_api.h ssh2.h ssherr.h misc.h sshbuf.h cipher.h cipher-chachapoly.h chacha.h poly1305.h cipher-aesctr.h rijndael.h digest.h sshkey.h match.h openbsd-compat/openssl-compat.h
 sshlogin.o: includes.h config.h defines.h platform.h openbsd-compat/openbsd-compat.h openbsd-compat/base64.h openbsd-compat/sigact.h openbsd-compat/readpassphrase.h openbsd-compat/vis.h openbsd-compat/getrrsetbyname.h openbsd-compat/sha1.h openbsd-compat/sha2.h openbsd-compat/rmd160.h openbsd-compat/md5.h openbsd-compat/blf.h openbsd-compat/getopt.h openbsd-compat/bsd-misc.h openbsd-compat/bsd-setres_id.h openbsd-compat/bsd-signal.h openbsd-compat/bsd-statvfs.h openbsd-compat/bsd-waitpid.h openbsd-compat/bsd-poll.h openbsd-compat/fake-rfc2553.h openbsd-compat/bsd-cygwin_util.h openbsd-compat/port-aix.h openbsd-compat/port-irix.h openbsd-compat/port-linux.h openbsd-compat/port-solaris.h openbsd-compat/port-net.h openbsd-compat/port-uw.h openbsd-compat/bsd-nextstep.h entropy.h sshlogin.h ssherr.h loginrec.h log.h sshbuf.h misc.h servconf.h
 sshpty.o: includes.h config.h defines.h platform.h openbsd-compat/openbsd-compat.h openbsd-compat/base64.h openbsd-compat/sigact.h openbsd-compat/readpassphrase.h openbsd-compat/vis.h openbsd-compat/getrrsetbyname.h openbsd-compat/sha1.h openbsd-compat/sha2.h openbsd-compat/rmd160.h openbsd-compat/md5.h openbsd-compat/blf.h openbsd-compat/getopt.h openbsd-compat/bsd-misc.h openbsd-compat/bsd-setres_id.h openbsd-compat/bsd-signal.h openbsd-compat/bsd-statvfs.h openbsd-compat/bsd-waitpid.h openbsd-compat/bsd-poll.h openbsd-compat/fake-rfc2553.h openbsd-compat/bsd-cygwin_util.h openbsd-compat/port-aix.h openbsd-compat/port-irix.h openbsd-compat/port-linux.h openbsd-compat/port-solaris.h openbsd-compat/port-net.h openbsd-compat/port-uw.h openbsd-compat/bsd-nextstep.h entropy.h sshpty.h log.h misc.h
 sshtty.o: includes.h config.h defines.h platform.h openbsd-compat/openbsd-compat.h openbsd-compat/base64.h openbsd-compat/sigact.h openbsd-compat/readpassphrase.h openbsd-compat/vis.h openbsd-compat/getrrsetbyname.h openbsd-compat/sha1.h openbsd-compat/sha2.h openbsd-compat/rmd160.h openbsd-compat/md5.h openbsd-compat/blf.h openbsd-compat/getopt.h openbsd-compat/bsd-misc.h openbsd-compat/bsd-setres_id.h openbsd-compat/bsd-signal.h openbsd-compat/bsd-statvfs.h openbsd-compat/bsd-waitpid.h openbsd-compat/bsd-poll.h openbsd-compat/fake-rfc2553.h openbsd-compat/bsd-cygwin_util.h openbsd-compat/port-aix.h openbsd-compat/port-irix.h openbsd-compat/port-linux.h openbsd-compat/port-solaris.h openbsd-compat/port-net.h openbsd-compat/port-uw.h openbsd-compat/bsd-nextstep.h entropy.h sshpty.h
diff --git a/Makefile.in b/Makefile.in
index 6abb60fd0..8b6754a68 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -197,7 +197,7 @@ ssh-keyscan$(EXEEXT): $(LIBCOMPAT) libssh.a ssh-keyscan.o
 	$(LD) -o $@ ssh-keyscan.o $(LDFLAGS) -lssh -lopenbsd-compat -lssh $(LIBS)
 
 sftp-server$(EXEEXT): $(LIBCOMPAT) libssh.a sftp.o sftp-common.o sftp-server.o sftp-realpath.o sftp-server-main.o
-	$(LD) -o $@ sftp-server.o sftp-common.o sftp-server-main.o $(LDFLAGS) -lssh -lopenbsd-compat $(LIBS)
+	$(LD) -o $@ sftp-server.o sftp-common.o sftp-realpath.o sftp-server-main.o $(LDFLAGS) -lssh -lopenbsd-compat $(LIBS)
 
 sftp$(EXEEXT): $(LIBCOMPAT) libssh.a sftp.o sftp-client.o sftp-common.o sftp-glob.o progressmeter.o
 	$(LD) -o $@ progressmeter.o sftp.o sftp-client.o sftp-common.o sftp-glob.o $(LDFLAGS) -lssh -lopenbsd-compat $(LIBS) $(LIBEDIT)
diff --git a/configure.ac b/configure.ac
index 23f4de7ef..532bdee83 100644
--- a/configure.ac
+++ b/configure.ac
@@ -588,7 +588,6 @@ case "$host" in
 	      #include <fcntl.h> ]
 	)
 	check_for_aix_broken_getaddrinfo=1
-	AC_DEFINE([BROKEN_REALPATH], [1], [Define if you have a broken realpath.])
 	AC_DEFINE([SETEUID_BREAKS_SETUID], [1],
 	    [Define if your platform breaks doing a seteuid before a setuid])
 	AC_DEFINE([BROKEN_SETREUID], [1], [Define if your setreuid() is broken])
@@ -948,7 +947,6 @@ mips-sony-bsd|mips-sony-newsos4)
 	conf_wtmp_location=/usr/adm/wtmp
 	maildir=/usr/spool/mail
 	AC_DEFINE([HAVE_NEXT], [1], [Define if you are on NeXT])
-	AC_DEFINE([BROKEN_REALPATH])
 	AC_DEFINE([USE_PIPES])
 	AC_DEFINE([BROKEN_SAVED_UIDS], [1], [Needed for NeXT])
 	;;
@@ -2024,32 +2022,6 @@ AC_CHECK_FUNCS([setresgid], [
 	)
 ])
 
-AC_CHECK_FUNCS([realpath], [
-	dnl the sftp v3 spec says SSH_FXP_REALPATH will "canonicalize any given
-	dnl path name", however some implementations of realpath (and some
-	dnl versions of the POSIX spec) do not work on non-existent files,
-	dnl so we use the OpenBSD implementation on those platforms.
-	AC_MSG_CHECKING([if realpath works with non-existent files])
-	AC_RUN_IFELSE(
-		[AC_LANG_PROGRAM([[
-#include <limits.h>
-#include <stdlib.h>
-#include <errno.h>
-		]], [[
-		char buf[PATH_MAX];
-		if (realpath("/opensshnonexistentfilename1234", buf) == NULL)
-			if (errno == ENOENT)
-				exit(1);
-		exit(0);
-		]])],
-		[AC_MSG_RESULT([yes])],
-		[AC_DEFINE([BROKEN_REALPATH], [1],
-			[realpath does not work with nonexistent files])
-		 AC_MSG_RESULT([no])],
-		[AC_MSG_WARN([cross compiling: assuming working])]
-	)
-])
-
 AC_MSG_CHECKING([for working fflush(NULL)])
 AC_RUN_IFELSE(
 	[AC_LANG_PROGRAM([[#include <stdio.h>]], [[fflush(NULL); exit(0);]])],
diff --git a/defines.h b/defines.h
index 8f4213062..46f88a431 100644
--- a/defines.h
+++ b/defines.h
@@ -108,10 +108,6 @@ enum
 #  define MAXPATHLEN PATH_MAX
 # else /* PATH_MAX */
 #  define MAXPATHLEN 64
-/* realpath uses a fixed buffer of size MAXPATHLEN, so force use of ours */
-#  ifndef BROKEN_REALPATH
-#   define BROKEN_REALPATH 1
-#  endif /* BROKEN_REALPATH */
 # endif /* PATH_MAX */
 #endif /* MAXPATHLEN */
 
diff --git a/openbsd-compat/Makefile.in b/openbsd-compat/Makefile.in
index c1e14cbd0..2cc343636 100644
--- a/openbsd-compat/Makefile.in
+++ b/openbsd-compat/Makefile.in
@@ -38,7 +38,6 @@ OPENBSD=base64.o \
 	pwcache.o \
 	readpassphrase.o \
 	reallocarray.o \
-	realpath.o \
 	recallocarray.o \
 	rmd160.o \
 	rresvport.o \
diff --git a/openbsd-compat/openbsd-compat.h b/openbsd-compat/openbsd-compat.h
index f58646886..86d45317b 100644
--- a/openbsd-compat/openbsd-compat.h
+++ b/openbsd-compat/openbsd-compat.h
@@ -81,18 +81,6 @@ void *reallocarray(void *, size_t, size_t);
 void *recallocarray(void *, size_t, size_t, size_t);
 #endif
 
-#if !defined(HAVE_REALPATH) || defined(BROKEN_REALPATH)
-/*
- * glibc's FORTIFY_SOURCE can redefine this and prevent us picking up the
- * compat version.
- */
-# ifdef BROKEN_REALPATH
-#  define realpath(x, y) _ssh_compat_realpath(x, y)
-# endif
-
-char *realpath(const char *path, char *resolved);
-#endif
-
 #ifndef HAVE_RRESVPORT_AF
 int rresvport_af(int *alport, sa_family_t af);
 #endif
diff --git a/openbsd-compat/realpath.c b/openbsd-compat/realpath.c
deleted file mode 100644
index a2f090e55..000000000
--- a/openbsd-compat/realpath.c
+++ /dev/null
@@ -1,229 +0,0 @@
-/*	$OpenBSD: realpath.c,v 1.20 2015/10/13 20:55:37 millert Exp $ */
-/*
- * Copyright (c) 2003 Constantin S. Svintsoff <kostik@iclub.nsu.ru>
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- * 3. The names of the authors may not be used to endorse or promote
- *    products derived from this software without specific prior written
- *    permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- */
-
-/* OPENBSD ORIGINAL: lib/libc/stdlib/realpath.c */
-
-#include "includes.h"
-
-#if !defined(HAVE_REALPATH) || defined(BROKEN_REALPATH)
-
-#include <sys/types.h>
-#include <sys/param.h>
-#include <sys/stat.h>
-
-#include <errno.h>
-#include <stdlib.h>
-#include <stddef.h>
-#include <string.h>
-#include <unistd.h>
-#include <limits.h>
-
-#ifndef SYMLOOP_MAX
-# define SYMLOOP_MAX 32
-#endif
-
-/* A slightly modified copy of this file exists in libexec/ld.so */
-
-/*
- * char *realpath(const char *path, char resolved[PATH_MAX]);
- *
- * Find the real name of path, by removing all ".", ".." and symlink
- * components.  Returns (resolved) on success, or (NULL) on failure,
- * in which case the path which caused trouble is left in (resolved).
- */
-char *
-realpath(const char *path, char *resolved)
-{
-	struct stat sb;
-	char *p, *q, *s;
-	size_t left_len, resolved_len;
-	unsigned symlinks;
-	int serrno, slen, mem_allocated;
-	char left[PATH_MAX], next_token[PATH_MAX], symlink[PATH_MAX];
-
-	if (path[0] == '\0') {
-		errno = ENOENT;
-		return (NULL);
-	}
-
-	serrno = errno;
-
-	if (resolved == NULL) {
-		resolved = malloc(PATH_MAX);
-		if (resolved == NULL)
-			return (NULL);
-		mem_allocated = 1;
-	} else
-		mem_allocated = 0;
-
-	symlinks = 0;
-	if (path[0] == '/') {
-		resolved[0] = '/';
-		resolved[1] = '\0';
-		if (path[1] == '\0')
-			return (resolved);
-		resolved_len = 1;
-		left_len = strlcpy(left, path + 1, sizeof(left));
-	} else {
-		if (getcwd(resolved, PATH_MAX) == NULL) {
-			if (mem_allocated)
-				free(resolved);
-			else
-				strlcpy(resolved, ".", PATH_MAX);
-			return (NULL);
-		}
-		resolved_len = strlen(resolved);
-		left_len = strlcpy(left, path, sizeof(left));
-	}
-	if (left_len >= sizeof(left) || resolved_len >= PATH_MAX) {
-		errno = ENAMETOOLONG;
-		goto err;
-	}
-
-	/*
-	 * Iterate over path components in `left'.
-	 */
-	while (left_len != 0) {
-		/*
-		 * Extract the next path component and adjust `left'
-		 * and its length.
-		 */
-		p = strchr(left, '/');
-		s = p ? p : left + left_len;
-		if (s - left >= (ptrdiff_t)sizeof(next_token)) {
-			errno = ENAMETOOLONG;
-			goto err;
-		}
-		memcpy(next_token, left, s - left);
-		next_token[s - left] = '\0';
-		left_len -= s - left;
-		if (p != NULL)
-			memmove(left, s + 1, left_len + 1);
-		if (resolved[resolved_len - 1] != '/') {
-			if (resolved_len + 1 >= PATH_MAX) {
-				errno = ENAMETOOLONG;
-				goto err;
-			}
-			resolved[resolved_len++] = '/';
-			resolved[resolved_len] = '\0';
-		}
-		if (next_token[0] == '\0')
-			continue;
-		else if (strcmp(next_token, ".") == 0)
-			continue;
-		else if (strcmp(next_token, "..") == 0) {
-			/*
-			 * Strip the last path component except when we have
-			 * single "/"
-			 */
-			if (resolved_len > 1) {
-				resolved[resolved_len - 1] = '\0';
-				q = strrchr(resolved, '/') + 1;
-				*q = '\0';
-				resolved_len = q - resolved;
-			}
-			continue;
-		}
-
-		/*
-		 * Append the next path component and lstat() it. If
-		 * lstat() fails we still can return successfully if
-		 * there are no more path components left.
-		 */
-		resolved_len = strlcat(resolved, next_token, PATH_MAX);
-		if (resolved_len >= PATH_MAX) {
-			errno = ENAMETOOLONG;
-			goto err;
-		}
-		if (lstat(resolved, &sb) != 0) {
-			if (errno == ENOENT && p == NULL) {
-				errno = serrno;
-				return (resolved);
-			}
-			goto err;
-		}
-		if (S_ISLNK(sb.st_mode)) {
-			if (symlinks++ > SYMLOOP_MAX) {
-				errno = ELOOP;
-				goto err;
-			}
-			slen = readlink(resolved, symlink, sizeof(symlink) - 1);
-			if (slen < 0)
-				goto err;
-			symlink[slen] = '\0';
-			if (symlink[0] == '/') {
-				resolved[1] = 0;
-				resolved_len = 1;
-			} else if (resolved_len > 1) {
-				/* Strip the last path component. */
-				resolved[resolved_len - 1] = '\0';
-				q = strrchr(resolved, '/') + 1;
-				*q = '\0';
-				resolved_len = q - resolved;
-			}
-
-			/*
-			 * If there are any path components left, then
-			 * append them to symlink. The result is placed
-			 * in `left'.
-			 */
-			if (p != NULL) {
-				if (symlink[slen - 1] != '/') {
-					if (slen + 1 >=
-					    (ptrdiff_t)sizeof(symlink)) {
-						errno = ENAMETOOLONG;
-						goto err;
-					}
-					symlink[slen] = '/';
-					symlink[slen + 1] = 0;
-				}
-				left_len = strlcat(symlink, left, sizeof(symlink));
-				if (left_len >= sizeof(symlink)) {
-					errno = ENAMETOOLONG;
-					goto err;
-				}
-			}
-			left_len = strlcpy(left, symlink, sizeof(left));
-		}
-	}
-
-	/*
-	 * Remove trailing slash except when the resolved pathname
-	 * is a single "/".
-	 */
-	if (resolved_len > 1 && resolved[resolved_len - 1] == '/')
-		resolved[resolved_len - 1] = '\0';
-	return (resolved);
-
-err:
-	if (mem_allocated)
-		free(resolved);
-	return (NULL);
-}
-#endif /* !defined(HAVE_REALPATH) || defined(BROKEN_REALPATH) */