2 * Copyright (c) 1994 Christos Zoulas
3 * Copyright (c) 1995 Frank van der Linden
4 * Copyright (c) 1995 Scott Bartram
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. The name of the author may not be used to endorse or promote products
16 * derived from this software without specific prior written permission
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 * from: svr4_util.c,v 1.5 1995/01/22 23:44:50 christos Exp
30 * $FreeBSD: src/sys/i386/ibcs2/ibcs2_util.c,v 1.7 1999/12/15 23:01:45 eivind Exp $
31 * $DragonFly: src/sys/emulation/ibcs2/i386/Attic/ibcs2_util.c,v 1.11 2006/05/06 02:43:11 dillon Exp $
34 #include <sys/param.h>
35 #include <sys/systm.h>
37 #include <sys/nlookup.h>
38 #include <sys/malloc.h>
39 #include <sys/vnode.h>
41 #include "ibcs2_util.h"
43 #include <vm/vm_zone.h>
45 const char ibcs2_emul_path[] = "/compat/ibcs2";
48 * Search an alternate path before passing pathname arguments on
49 * to system calls. Useful for keeping a separate 'emulation tree'.
51 * If cflag is set, we check if an attempt can be made to create
52 * the named file, i.e. we check if the directory it should
56 * sgp: Pointer to stackgap memory
59 ibcs2_emul_find(caddr_t *sgp, const char *prefix, char *path,
60 char **pbuf, int cflag)
62 struct nlookupdata nd;
63 struct nlookupdata ndroot;
71 buf = (char *) malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
74 for (ptr = buf; (*ptr = *prefix) != '\0'; ptr++, prefix++)
77 sz = MAXPATHLEN - (ptr - buf);
80 * If sgp is not given then the path is already in kernel space
83 error = copystr(path, ptr, sz, &len);
85 error = copyinstr(path, ptr, sz, &len);
98 * We know that there is a / somewhere in this pathname.
99 * Search backwards for it, to find the file's parent dir
100 * to see if it exists in the alternate tree. If it does,
101 * and we want to create a file (cflag is set). We don't
102 * need to worry about the root comparison in this case.
106 for (cp = &ptr[len] - 1; *cp != '/'; cp--);
109 error = nlookup_init(&nd, buf, UIO_SYSSPACE, NLC_FOLLOW);
111 error = nlookup(&nd);
119 error = nlookup_init(&nd, buf, UIO_SYSSPACE, NLC_FOLLOW);
121 error = nlookup(&nd);
128 * We now compare the vnode of the ibcs2_root to the one
129 * vnode asked. If they resolve to be the same, then we
130 * ignore the match so that the real root gets used.
131 * This avoids the problem of traversing "../.." to find the
132 * root directory and never finding it, because "/" resolves
133 * to the emulation root directory. This is expensive :-(
135 error = nlookup_init(&ndroot, ibcs2_emul_path, UIO_SYSSPACE,
138 error = nlookup(&ndroot);
140 error = cache_vref(nd.nl_ncp, nd.nl_cred, &vp);
143 error = VOP_GETATTR(vp, &vat);
146 error = cache_vref(ndroot.nl_ncp, nd.nl_cred, &vp);
149 error = VOP_GETATTR(vp, &vatroot);
154 if (vat.va_fsid == vatroot.va_fsid &&
155 vat.va_fileid == vatroot.va_fileid) {
164 sz = &ptr[len] - buf;
165 *pbuf = stackgap_alloc(sgp, sz + 1);
166 error = copyout(buf, *pbuf, sz);
172 nlookup_done(&ndroot);