lib/libc/stdio/tmpfile.c

   1 /*      $NetBSD: tmpfile.c,v 1.12 2012/03/15 18:22:30 christos Exp $    */
   2
   3 /*-
   4  * Copyright (c) 1990, 1993
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * This code is derived from software contributed to Berkeley by
   8  * Chris Torek.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 3. Neither the name of the University nor the names of its contributors
  19  *    may be used to endorse or promote products derived from this software
  20  *    without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  */
  34
  35 #include <sys/cdefs.h>
  36 #if defined(LIBC_SCCS) && !defined(lint)
  37 #if 0
  38 static char sccsid[] = "@(#)tmpfile.c   8.1 (Berkeley) 6/4/93";
  39 #else
  40 __RCSID("$NetBSD: tmpfile.c,v 1.12 2012/03/15 18:22:30 christos Exp $");
  41 #endif
  42 #endif /* LIBC_SCCS and not lint */
  43
  44 #include "namespace.h"
  45 #include <sys/types.h>
  46 #include <unistd.h>
  47 #include <signal.h>
  48 #include <errno.h>
  49 #include <stdio.h>
  50 #include <stdlib.h>
  51 #include <string.h>
  52 #include <paths.h>
  53
  54 FILE *
  55 tmpfile(void)
  56 {
  57         sigset_t set, oset;
  58         FILE *fp;
  59         int fd, sverrno;
  60 #define TRAILER "tmp.XXXXXXXXXX"
  61         char buf[sizeof(_PATH_TMP) + sizeof(TRAILER)];
  62
  63         (void)memcpy(buf, _PATH_TMP, sizeof(_PATH_TMP) - 1);
  64         (void)memcpy(buf + sizeof(_PATH_TMP) - 1, TRAILER, sizeof(TRAILER));
  65
  66         sigfillset(&set);
  67         (void)sigprocmask(SIG_BLOCK, &set, &oset);
  68
  69         fd = mkstemp(buf);
  70         if (fd != -1)
  71                 (void)unlink(buf);
  72
  73         (void)sigprocmask(SIG_SETMASK, &oset, NULL);
  74
  75         if (fd == -1)
  76                 return NULL;
  77
  78         if ((fp = fdopen(fd, "w+")) == NULL) {
  79                 sverrno = errno;
  80                 (void)close(fd);
  81                 errno = sverrno;
  82                 return NULL;
  83         }
  84         return fp;
  85 }