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  * 4. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * @(#)tempnam.c        8.1 (Berkeley) 6/4/93
  30  * $FreeBSD: src/lib/libc/stdio/tempnam.c,v 1.11 2007/01/09 00:28:07 imp Exp $
  31  * $DragonFly: src/lib/libc/stdio/tempnam.c,v 1.5 2005/11/20 11:07:30 swildner Exp $
  32  */
  33
  34 #include <sys/param.h>
  35 #include <errno.h>
  36 #include <stdio.h>
  37 #include <stdlib.h>
  38 #include <string.h>
  39 #include <unistd.h>
  40 #include <paths.h>
  41
  42 __warn_references(tempnam,
  43     "warning: tempnam() possibly used unsafely; consider using mkstemp()");
  44
  45 extern char *_mktemp(char *);
  46
  47 char *
  48 tempnam(const char *dir, const char *pfx)
  49 {
  50         int sverrno;
  51         char *f, *name;
  52
  53         if (!(name = malloc(MAXPATHLEN)))
  54                 return(NULL);
  55
  56         if (!pfx)
  57                 pfx = "tmp.";
  58
  59         if (issetugid() == 0 && (f = getenv("TMPDIR"))) {
  60                 snprintf(name, MAXPATHLEN, "%s%s%sXXXXXX", f,
  61                     *(f + strlen(f) - 1) == '/'? "": "/", pfx);
  62                 if ((f = _mktemp(name)))
  63                         return(f);
  64         }
  65
  66         if ((f = (char *)dir)) {
  67                 snprintf(name, MAXPATHLEN, "%s%s%sXXXXXX", f,
  68                     *(f + strlen(f) - 1) == '/'? "": "/", pfx);
  69                 if ((f = _mktemp(name)))
  70                         return(f);
  71         }
  72
  73         f = P_tmpdir;
  74         snprintf(name, MAXPATHLEN, "%s%sXXXXXX", f, pfx);
  75         if ((f = _mktemp(name)))
  76                 return(f);
  77
  78         f = _PATH_TMP;
  79         snprintf(name, MAXPATHLEN, "%s%sXXXXXX", f, pfx);
  80         if ((f = _mktemp(name)))
  81                 return(f);
  82
  83         sverrno = errno;
  84         free(name);
  85         errno = sverrno;
  86         return(NULL);
  87 }