lib/libc/stdio/tempnam.c

   1 /*
   2  * Copyright (c) 1988, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  * @(#)tempnam.c        8.1 (Berkeley) 6/4/93
  34  * $FreeBSD: src/lib/libc/stdio/tempnam.c,v 1.8 1999/10/24 11:57:24 ache Exp $
  35  * $DragonFly: src/lib/libc/stdio/tempnam.c,v 1.5 2005/11/20 11:07:30 swildner Exp $
  36  */
  37
  38 #include <sys/param.h>
  39 #include <errno.h>
  40 #include <stdio.h>
  41 #include <stdlib.h>
  42 #include <string.h>
  43 #include <unistd.h>
  44 #include <paths.h>
  45
  46 __warn_references(tempnam,
  47     "warning: tempnam() possibly used unsafely; consider using mkstemp()");
  48
  49 extern char *_mktemp (char *);
  50
  51 char *
  52 tempnam(const char *dir, const char *pfx)
  53 {
  54         int sverrno;
  55         char *f, *name;
  56
  57         if (!(name = malloc(MAXPATHLEN)))
  58                 return(NULL);
  59
  60         if (!pfx)
  61                 pfx = "tmp.";
  62
  63         if (issetugid() == 0 && (f = getenv("TMPDIR"))) {
  64                 snprintf(name, MAXPATHLEN, "%s%s%sXXXXXX", f,
  65                     *(f + strlen(f) - 1) == '/'? "": "/", pfx);
  66                 if ((f = _mktemp(name)))
  67                         return(f);
  68         }
  69
  70         if ((f = (char *)dir)) {
  71                 snprintf(name, MAXPATHLEN, "%s%s%sXXXXXX", f,
  72                     *(f + strlen(f) - 1) == '/'? "": "/", pfx);
  73                 if ((f = _mktemp(name)))
  74                         return(f);
  75         }
  76
  77         f = P_tmpdir;
  78         snprintf(name, MAXPATHLEN, "%s%sXXXXXX", f, pfx);
  79         if ((f = _mktemp(name)))
  80                 return(f);
  81
  82         f = _PATH_TMP;
  83         snprintf(name, MAXPATHLEN, "%s%sXXXXXX", f, pfx);
  84         if ((f = _mktemp(name)))
  85                 return(f);
  86
  87         sverrno = errno;
  88         free(name);
  89         errno = sverrno;
  90         return(NULL);
  91 }