1 /* Utilities for reading/writing fstab, mtab, etc.
2 Copyright (C) 1995, 1996, 1997, 2000 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, write to the Free
17 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
18 02111-1307 USA. */
19
20 #include <features.h>
21 #include <mntent.h>
22 #include <stdlib.h>
23 #include <libc-symbols.h>
24 #define _LIBC 1
25 #define NOT_IN_libc 1
26 #include <bits/libc-lock.h>
27
28 /* We don't want to allocate the static buffer all the time since it
29 is not always used (in fact, rather infrequently). Accept the
30 extra cost of a `malloc'. */
31 static char *getmntent_buffer;
32
33 /* This is the size of the buffer. This is really big. */
34 #define BUFFER_SIZE 4096
35
36
37 static void
allocate(void)38 allocate (void)
39 {
40 getmntent_buffer = (char *) malloc (BUFFER_SIZE);
41 }
42
43
44 struct mntent *
getmntent(FILE * stream)45 getmntent (FILE *stream)
46 {
47 static struct mntent m;
48 static int once;
49
50 do {
51 if (__pthread_once != NULL)
52 __pthread_once (&once, allocate);
53 else if (once == 0) {
54 allocate ();
55 once = !(0);
56 }
57 } while (0);
58
59
60 if (getmntent_buffer == NULL)
61 /* If no core is available we don't have a chance to run the
62 program successfully and so returning NULL is an acceptable
63 result. */
64 return NULL;
65
66 return __getmntent_r (stream, &m, getmntent_buffer, BUFFER_SIZE);
67 }
68
69
70 /* Make sure the memory is freed if the programs ends while in
71 memory-debugging mode and something actually was allocated. */
72 static void
73 __attribute__ ((unused))
free_mem(void)74 free_mem (void)
75 {
76 free (getmntent_buffer);
77 }
78
79 text_set_element (__libc_subfreeres, free_mem);
80