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Diffstat (limited to 'sysdeps/unix/sysv/linux/shm-directory.c')
-rw-r--r--sysdeps/unix/sysv/linux/shm-directory.c147
1 files changed, 0 insertions, 147 deletions
diff --git a/sysdeps/unix/sysv/linux/shm-directory.c b/sysdeps/unix/sysv/linux/shm-directory.c
deleted file mode 100644
index ea6d2a46c1..0000000000
--- a/sysdeps/unix/sysv/linux/shm-directory.c
+++ /dev/null
@@ -1,147 +0,0 @@
-/* Determine directory for shm/sem files. Linux version.
- Copyright (C) 2000-2021 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 Lesser General Public
- License as published by the Free Software Foundation; either
- version 2.1 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
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public
- License along with the GNU C Library; if not, see
- <https://www.gnu.org/licenses/>. */
-
-#include "shm-directory.h"
-
-#include <errno.h>
-#include <mntent.h>
-#include <paths.h>
-#include <stdio.h>
-#include <string.h>
-#include <sys/statfs.h>
-#include <libc-lock.h>
-#include "linux_fsinfo.h"
-
-
-/* Mount point of the shared memory filesystem. */
-static struct
-{
- char *dir;
- size_t dirlen;
-} mountpoint;
-
-/* This is the default directory. */
-static const char defaultdir[] = "/dev/shm/";
-
-/* Protect the `mountpoint' variable above. */
-__libc_once_define (static, once);
-
-
-/* Determine where the shmfs is mounted (if at all). */
-static void
-where_is_shmfs (void)
-{
- char buf[512];
- struct statfs f;
- struct mntent resmem;
- struct mntent *mp;
- FILE *fp;
-
- /* The canonical place is /dev/shm. This is at least what the
- documentation tells everybody to do. */
- if (__statfs (defaultdir, &f) == 0 && (f.f_type == SHMFS_SUPER_MAGIC
- || f.f_type == RAMFS_MAGIC))
- {
- /* It is in the normal place. */
- mountpoint.dir = (char *) defaultdir;
- mountpoint.dirlen = sizeof (defaultdir) - 1;
-
- return;
- }
-
- /* OK, do it the hard way. Look through the /proc/mounts file and if
- this does not exist through /etc/fstab to find the mount point. */
- fp = __setmntent ("/proc/mounts", "r");
- if (__glibc_unlikely (fp == NULL))
- {
- fp = __setmntent (_PATH_MNTTAB, "r");
- if (__glibc_unlikely (fp == NULL))
- /* There is nothing we can do. Blind guesses are not helpful. */
- return;
- }
-
- /* Now read the entries. */
- while ((mp = __getmntent_r (fp, &resmem, buf, sizeof buf)) != NULL)
- /* The original name is "shm" but this got changed in early Linux
- 2.4.x to "tmpfs". */
- if (strcmp (mp->mnt_type, "tmpfs") == 0
- || strcmp (mp->mnt_type, "shm") == 0)
- {
- /* Found it. There might be more than one place where the
- filesystem is mounted but one is enough for us. */
- size_t namelen;
-
- /* First make sure this really is the correct entry. At least
- some versions of the kernel give wrong information because
- of the implicit mount of the shmfs for SysV IPC. */
- if (__statfs (mp->mnt_dir, &f) != 0 || (f.f_type != SHMFS_SUPER_MAGIC
- && f.f_type != RAMFS_MAGIC))
- continue;
-
- namelen = strlen (mp->mnt_dir);
-
- if (namelen == 0)
- /* Hum, maybe some crippled entry. Keep on searching. */
- continue;
-
- mountpoint.dir = (char *) malloc (namelen + 2);
- if (mountpoint.dir != NULL)
- {
- char *cp = __mempcpy (mountpoint.dir, mp->mnt_dir, namelen);
- if (cp[-1] != '/')
- *cp++ = '/';
- *cp = '\0';
- mountpoint.dirlen = cp - mountpoint.dir;
- }
-
- break;
- }
-
- /* Close the stream. */
- __endmntent (fp);
-}
-
-
-const char *
-__shm_directory (size_t *len)
-{
- /* Determine where the shmfs is mounted. */
- __libc_once (once, where_is_shmfs);
-
- /* If we don't know the mount points there is nothing we can do. Ever. */
- if (__glibc_unlikely (mountpoint.dir == NULL))
- {
- __set_errno (ENOSYS);
- return NULL;
- }
-
- *len = mountpoint.dirlen;
- return mountpoint.dir;
-}
-#if IS_IN (libpthread)
-hidden_def (__shm_directory)
-
-/* Make sure the table is freed if we want to free everything before
- exiting. */
-void
-__shm_directory_freeres (void)
-{
- if (mountpoint.dir != defaultdir)
- free (mountpoint.dir);
-}
-#endif