stdio/FreeBSD/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
  30 #if defined(LIBC_SCCS) && !defined(lint)
  31 static char sccsid[] = "@(#)tempnam.c   8.1 (Berkeley) 6/4/93";
  32 #endif /* LIBC_SCCS and not lint */
  33 #include <sys/cdefs.h>
  34 __FBSDID("$FreeBSD: src/lib/libc/stdio/tempnam.c,v 1.11 2007/01/09 00:28:07 imp Exp $");
  35
  36 #include <sys/param.h>
  37 #include <errno.h>
  38 #include <stdio.h>
  39 #include <stdlib.h>
  40 #include <string.h>
  41 #include <unistd.h>
  42 #include <paths.h>
  43
  44 __warn_references(tempnam,
  45     "warning: tempnam() possibly used unsafely; consider using mkstemp()");
  46
  47 extern char *_mktemp(char *);
  48
  49 char *
  50 tempnam(dir, pfx)
  51         const char *dir, *pfx;
  52 {
  53         int sverrno;
  54         char *f, *name;
  55
  56         if (!(name = malloc(MAXPATHLEN))) {
  57                 return(NULL);
  58         }
  59
  60         if (!pfx)
  61                 pfx = "tmp.";
  62
  63 #if !__DARWIN_UNIX03
  64         if (issetugid() == 0 && (f = getenv("TMPDIR"))) {
  65                 (void)snprintf(name, MAXPATHLEN, "%s%s%sXXXXXX", f,
  66                     *(f + strlen(f) - 1) == '/'? "": "/", pfx);
  67                 if ((f = _mktemp(name))) {
  68                         return(f);
  69                 }
  70         }
  71 #endif /* !__DARWIN_UNIX03 */
  72         if ((f = (char *)dir)) {
  73 #if __DARWIN_UNIX03
  74             if (access(dir, W_OK) == 0) {
  75 #endif /* __DARWIN_UNIX03 */
  76                 (void)snprintf(name, MAXPATHLEN, "%s%s%sXXXXXX", f,
  77                     *(f + strlen(f) - 1) == '/'? "": "/", pfx);
  78                 if ((f = _mktemp(name))) {
  79                         return(f);
  80                 }
  81 #if __DARWIN_UNIX03
  82             }
  83 #endif /* __DARWIN_UNIX03 */
  84         }
  85
  86         f = P_tmpdir;
  87 #if __DARWIN_UNIX03
  88         if (access(f, W_OK) == 0) {     /* directory accessible? */
  89 #endif /* __DARWIN_UNIX03 */
  90         (void)snprintf(name, MAXPATHLEN, "%s%sXXXXXX", f, pfx);
  91         if ((f = _mktemp(name))) {
  92                 return(f);
  93         }
  94
  95 #if __DARWIN_UNIX03
  96         }
  97         if (issetugid() == 0 && (f = getenv("TMPDIR")) && access(f, W_OK) == 0) {
  98                 (void)snprintf(name, MAXPATHLEN, "%s%s%sXXXXXX", f,
  99                     *(f + strlen(f) - 1) == '/'? "": "/", pfx);
 100                 if ((f = _mktemp(name))) {
 101                         return(f);
 102                 }
 103         }
 104 #endif /* __DARWIN_UNIX03 */
 105         f = _PATH_TMP;
 106         (void)snprintf(name, MAXPATHLEN, "%s%sXXXXXX", f, pfx);
 107         if ((f = _mktemp(name))) {
 108                 return(f);
 109         }
 110
 111         sverrno = errno;
 112         free(name);
 113         errno = sverrno;
 114         return(NULL);
 115 }