File: mkstemp.c

package info (click to toggle)
libc-sparc 5.3.12-2
  • links: PTS
  • area: main
  • in suites: hamm
  • size: 18,664 kB
  • ctags: 53,237
  • sloc: ansic: 181,379; asm: 5,080; makefile: 3,340; lex: 521; sh: 439; yacc: 401; awk: 28
file content (60 lines) | stat: -rw-r--r-- 1,928 bytes parent folder | download | duplicates (6)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
/* Copyright (C) 1991, 1992, 1993 Free Software Foundation, Inc.
This file is part of the GNU C Library.

The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.

The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Library General Public License for more details.

You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB.  If
not, write to the Free Software Foundation, Inc., 675 Mass Ave,
Cambridge, MA 02139, USA.  */

#include <ansidecl.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <stdio.h>
#include <fcntl.h>
#include <sys/types.h>

/* Return a file descriptor with a unique temporary file name from
   TEMPLATE. The last six characters of TEMPLATE must be "XXXXXX";
   they are replaced with a string that makes the filename unique.
   Return -1 if no suitable file could be created. */
int
DEFUN(mkstemp, (template), char *template)
{
  static CONST char letters[]
    = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
  CONST char *ptr = letters;
  pid_t pid = __getpid();
  int fd;
  size_t len;

  len = strlen(template);
  if (len < 6 || strcmp(&template[len - 6], "XXXXXX"))
    {
      errno = EINVAL;
      return -1;
    }

  if (sprintf (&template[len - 5], "%.5u",
  	 (unsigned int) pid % 100000) != 5)
    return -1;

  while (*ptr != '\0') {
    template[len - 6] = *ptr++;
    /* Make sure `template' doesn't exist. */
    fd = __open (template, O_RDWR | O_CREAT | O_EXCL, 0666);
    if (fd >= 0 || errno != EEXIST) return fd;
  }

  return -1;
}