stdio/tmpfile-fbsd.c

   1 /*-
   2  * Copyright (c) 1990, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * This code is derived from software contributed to Berkeley by
   6  * Chris Torek.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. All advertising materials mentioning features or use of this software
  17  *    must display the following acknowledgement:
  18  *      This product includes software developed by the University of
  19  *      California, Berkeley and its contributors.
  20  * 4. Neither the name of the University nor the names of its contributors
  21  *    may be used to endorse or promote products derived from this software
  22  *    without specific prior written permission.
  23  *
  24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  34  * SUCH DAMAGE.
  35  */
  36
  37 #if defined(LIBC_SCCS) && !defined(lint)
  38 static char sccsid[] = "@(#)tmpfile.c   8.1 (Berkeley) 6/4/93";
  39 #endif /* LIBC_SCCS and not lint */
  40 #include <sys/cdefs.h>
  41 __FBSDID("$FreeBSD: src/lib/libc/stdio/tmpfile.c,v 1.9 2003/02/06 01:08:19 mtm Exp $");
  42
  43 #include "namespace.h"
  44 #include <sys/types.h>
  45 #include <signal.h>
  46 #include <unistd.h>
  47 #include <errno.h>
  48 #include <stdio.h>
  49 #include <stdlib.h>
  50 #include <string.h>
  51 #include <paths.h>
  52 #include "un-namespace.h"
  53
  54 FILE *
  55 tmpfile()
  56 {
  57         sigset_t set, oset;
  58         FILE *fp;
  59         int fd, sverrno;
  60 #define TRAILER "tmp.XXXXXX"
  61         char *buf;
  62         const char *tmpdir;
  63
  64         tmpdir = NULL;
  65         if (issetugid() == 0)
  66                 tmpdir = getenv("TMPDIR");
  67         if (tmpdir == NULL)
  68                 tmpdir = _PATH_TMP;
  69
  70         (void)asprintf(&buf, "%s%s%s", tmpdir,
  71             (tmpdir[strlen(tmpdir) - 1] == '/') ? "" : "/", TRAILER);
  72         if (buf == NULL)
  73                 return (NULL);
  74
  75         sigfillset(&set);
  76         (void)_sigprocmask(SIG_BLOCK, &set, &oset);
  77
  78         fd = mkstemp(buf);
  79         if (fd != -1)
  80                 (void)unlink(buf);
  81
  82         free(buf);
  83
  84         (void)_sigprocmask(SIG_SETMASK, &oset, NULL);
  85
  86         if (fd == -1)
  87                 return (NULL);
  88
  89         if ((fp = fdopen(fd, "w+")) == NULL) {
  90                 sverrno = errno;
  91                 (void)_close(fd);
  92                 errno = sverrno;
  93                 return (NULL);
  94         }
  95         return (fp);
  96 }