NetBSD/lib/libc/stdio/gettemp.c
christos a803d40076 PR/47757: Eric Radman: mktemp(3) mangles the pathname if not given an absolute
path
1. on error, gettemp() did not restore the path string
2. when emulating mktemp() it is not an error for the pattern not to represent
   a real directory structure
XXX[1]: pullup-5, pullup-6
XXX[2]: the default pattern is the simplistic <pid><X> for mktemp.
2013-04-22 20:57:36 +00:00

170 lines
4.4 KiB
C

/* $NetBSD: gettemp.c,v 1.16 2013/04/22 20:57:36 christos Exp $ */
/*
* Copyright (c) 1987, 1993
* The Regents of the University of California. All rights reserved.
*
* 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. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*/
#if HAVE_NBTOOL_CONFIG_H
#include "nbtool_config.h"
#endif
#if !HAVE_NBTOOL_CONFIG_H || !HAVE_MKSTEMP || !HAVE_MKDTEMP
#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
#if 0
static char sccsid[] = "@(#)mktemp.c 8.1 (Berkeley) 6/4/93";
#else
__RCSID("$NetBSD: gettemp.c,v 1.16 2013/04/22 20:57:36 christos Exp $");
#endif
#endif /* LIBC_SCCS and not lint */
#include <sys/types.h>
#include <sys/stat.h>
#include <assert.h>
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#if HAVE_NBTOOL_CONFIG_H
#define GETTEMP __nbcompat_gettemp
#else
#include "reentrant.h"
#include "local.h"
#define GETTEMP __gettemp
#endif
int
GETTEMP(char *path, int *doopen, int domkdir)
{
char *start, *trv;
struct stat sbuf;
u_int pid;
/* To guarantee multiple calls generate unique names even if
the file is not created. 676 different possibilities with 7
or more X's, 26 with 6 or less. */
static char xtra[2] = "aa";
int xcnt = 0;
_DIAGASSERT(path != NULL);
/* doopen may be NULL */
pid = getpid();
/* Move to end of path and count trailing X's. */
for (trv = path; *trv; ++trv)
if (*trv == 'X')
xcnt++;
else
xcnt = 0;
/* Use at least one from xtra. Use 2 if more than 6 X's. */
if (*(trv - 1) == 'X')
*--trv = xtra[0];
if (xcnt > 6 && *(trv - 1) == 'X')
*--trv = xtra[1];
/* Set remaining X's to pid digits with 0's to the left. */
while (*--trv == 'X') {
*trv = (pid % 10) + '0';
pid /= 10;
}
/* update xtra for next call. */
if (xtra[0] != 'z')
xtra[0]++;
else {
xtra[0] = 'a';
if (xtra[1] != 'z')
xtra[1]++;
else
xtra[1] = 'a';
}
/*
* check the target directory; if you have six X's and it
* doesn't exist this runs for a *very* long time.
*/
for (start = trv + 1;; --trv) {
if (trv <= path)
break;
if (*trv == '/') {
int e;
*trv = '\0';
e = stat(path, &sbuf);
*trv = '/';
if (e == -1)
return doopen == NULL && !domkdir;
if (!S_ISDIR(sbuf.st_mode)) {
errno = ENOTDIR;
return doopen == NULL && !domkdir;
}
break;
}
}
for (;;) {
if (doopen) {
if ((*doopen =
open(path, O_CREAT | O_EXCL | O_RDWR, 0600)) >= 0)
return 1;
if (errno != EEXIST)
return 0;
} else if (domkdir) {
if (mkdir(path, 0700) >= 0)
return 1;
if (errno != EEXIST)
return 0;
} else if (lstat(path, &sbuf))
return errno == ENOENT ? 1 : 0;
/* tricky little algorithm for backward compatibility */
for (trv = start;;) {
if (!*trv)
return 0;
if (*trv == 'z')
*trv++ = 'a';
else {
if (isdigit((unsigned char)*trv))
*trv = 'a';
else
++*trv;
break;
}
}
}
/*NOTREACHED*/
}
#endif /* !HAVE_NBTOOL_CONFIG_H || !HAVE_MKSTEMP || !HAVE_MKDTEMP */