@@ -3,3 +3,7 @@ L_tmpnam = 20
TMP_MAX = 238328
L_ctermid = 9
L_cuserid = 9
+
+ifeq ($(subdir),rt)
+librt-routines += shm-directory
+endif
new file mode 100644
@@ -0,0 +1,35 @@
+/* Determine directory for shm/sem files. Generic POSIX version.
+ Copyright (C) 2014 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
+ <http://www.gnu.org/licenses/>. */
+
+#include "shm-directory.h"
+#include <unistd.h>
+
+#if _POSIX_MAPPED_FILES
+
+# include <paths.h>
+
+# define SHMDIR (_PATH_DEV "shm/")
+
+const char *
+__shm_directory (size_t *len)
+{
+ *len = sizeof SHMDIR - 1;
+ return SHMDIR;
+}
+
+#endif
new file mode 100644
@@ -0,0 +1,63 @@
+/* Header for directory for shm/sem files.
+ Copyright (C) 2014 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
+ <http://www.gnu.org/licenses/>. */
+
+#ifndef _SHM_DIRECTORY_H
+
+#include <errno.h>
+#include <limits.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+
+extern const char *__shm_directory (size_t *len);
+
+/* This defines local variables SHM_DIR and SHM_DIRLEN, giving the
+ directory prefix (with trailing slash) and length (not including '\0'
+ terminator) of the directory used for shm files. If that cannot be
+ determined, it sets errno to ENOSYS and returns RETVAL_FOR_INVALID.
+
+ This uses the local variable NAME as an lvalue, and increments it past
+ any leading slashes. It then defines the local variable NAMELEN, giving
+ strlen (NAME) + 1. If NAME is invalid, it sets errno to
+ ERRNO_FOR_INVALID and returns RETVAL_FOR_INVALID. Finally, it defines
+ the local variable SHM_NAME, giving the absolute file name of the shm
+ file corresponding to NAME. */
+
+#define SHM_GET_NAME(errno_for_invalid, retval_for_invalid) \
+ size_t shm_dirlen; \
+ const char *shm_dir = __shm_directory (&shm_dirlen); \
+ /* If we don't know what directory to use, there is nothing we can do. */ \
+ if (__glibc_unlikely (shm_dir == NULL)) \
+ { \
+ __set_errno (ENOSYS); \
+ return retval_for_invalid; \
+ } \
+ /* Construct the filename. */ \
+ while (name[0] == '/') \
+ ++name; \
+ size_t namelen = strlen (name) + 1; \
+ /* Validate the filename. */ \
+ if (namelen == 1 || namelen >= NAME_MAX || strchr (name, '/') != NULL) \
+ { \
+ __set_errno (errno_for_invalid); \
+ return retval_for_invalid; \
+ } \
+ char *shm_name = __alloca (shm_dirlen + namelen); \
+ __mempcpy (__mempcpy (shm_name, shm_dir, shm_dirlen), name, namelen)
+
+#endif /* shm-directory.h */
@@ -19,50 +19,41 @@
#include <unistd.h>
#if ! _POSIX_MAPPED_FILES
-#include <rt/shm_open.c>
+
+# include <rt/shm_open.c>
#else
-#include <errno.h>
-#include <sys/mman.h>
-#include <fcntl.h>
-#include <string.h>
-#include <stdlib.h>
-#include <paths.h>
+# include <fcntl.h>
+# include <shm-directory.h>
-#define SHMDIR (_PATH_DEV "shm/")
/* Open shared memory object. */
int
shm_open (const char *name, int oflag, mode_t mode)
{
- size_t namelen;
- char *fname;
- int fd;
-
- /* Construct the filename. */
- while (name[0] == '/')
- ++name;
-
- if (name[0] == '\0')
- {
- /* The name "/" is not supported. */
- __set_errno (EINVAL);
- return -1;
- }
-
- namelen = strlen (name);
- fname = (char *) __alloca (sizeof SHMDIR - 1 + namelen + 1);
- __mempcpy (__mempcpy (fname, SHMDIR, sizeof SHMDIR - 1),
- name, namelen + 1);
-
- fd = open (name, oflag, mode);
+ SHM_GET_NAME (EINVAL, -1);
+
+# ifdef O_NOFOLLOW
+ oflag |= O_NOFOLLOW;
+# endif
+# ifdef O_CLOEXEC
+ oflag |= O_CLOEXEC;
+# endif
+ int fd = open (shm_name, oflag, mode);
+ if (fd == -1 && __glibc_unlikely (errno == EISDIR))
+ /* It might be better to fold this error with EINVAL since
+ directory names are just another example for unsuitable shared
+ object names and the standard does not mention EISDIR. */
+ __set_errno (EINVAL);
+
+# ifndef O_CLOEXEC
if (fd != -1)
{
/* We got a descriptor. Now set the FD_CLOEXEC bit. */
int flags = fcntl (fd, F_GETFD, 0);
- if (__builtin_expect (flags, 0) != -1)
+ if (__glibc_likely (flags != -1))
{
flags |= FD_CLOEXEC;
flags = fcntl (fd, F_SETFD, flags);
@@ -77,8 +68,9 @@ shm_open (const char *name, int oflag, mode_t mode)
__set_errno (save_errno);
}
}
+# endif
return fd;
}
-#endif
+#endif /* _POSIX_MAPPED_FILES */
@@ -24,37 +24,20 @@
#else
#include <errno.h>
-#include <sys/mman.h>
#include <string.h>
-#include <stdlib.h>
-#include <paths.h>
+#include "shm-directory.h"
-#define SHMDIR (_PATH_DEV "shm/")
/* Remove shared memory object. */
int
shm_unlink (const char *name)
{
- size_t namelen;
- char *fname;
-
- /* Construct the filename. */
- while (name[0] == '/')
- ++name;
-
- if (name[0] == '\0')
- {
- /* The name "/" is not supported. */
- __set_errno (EINVAL);
- return -1;
- }
-
- namelen = strlen (name);
- fname = (char *) __alloca (sizeof SHMDIR - 1 + namelen + 1);
- __mempcpy (__mempcpy (fname, SHMDIR, sizeof SHMDIR - 1),
- name, namelen + 1);
-
- return unlink (name);
+ SHM_GET_NAME (ENOENT, -1);
+
+ int result = unlink (shm_name);
+ if (result < 0 && errno == EPERM)
+ __set_errno (EACCES);
+ return result;
}
#endif
new file mode 100644
@@ -0,0 +1,144 @@
+/* Determine directory for shm/sem files. Linux version.
+ Copyright (C) 2000-2014 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
+ <http://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 <bits/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;
+}
+
+
+/* Make sure the table is freed if we want to free everything before
+ exiting. */
+libc_freeres_fn (freeit)
+{
+ if (mountpoint.dir != defaultdir)
+ free (mountpoint.dir);
+}
deleted file mode 100644
@@ -1,226 +0,0 @@
-/* Copyright (C) 2000-2014 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
- <http://www.gnu.org/licenses/>. */
-
-#include <errno.h>
-#include <fcntl.h>
-#include <mntent.h>
-#include <paths.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-#include <sys/mman.h>
-#include <sys/statfs.h>
-#include <bits/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);
-}
-
-
-/* Open shared memory object. This implementation assumes the shmfs
- implementation introduced in the late 2.3.x kernel series to be
- available. Normally the filesystem will be mounted at /dev/shm but
- we fall back on searching for the actual mount point should opening
- such a file fail. */
-int
-shm_open (const char *name, int oflag, mode_t mode)
-{
- size_t namelen;
- char *fname;
- int fd;
-
- /* 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 (mountpoint.dir == NULL)
- {
- __set_errno (ENOSYS);
- return -1;
- }
-
- /* Construct the filename. */
- while (name[0] == '/')
- ++name;
-
- namelen = strlen (name);
-
- /* Validate the filename. */
- if (name[0] == '\0' || namelen > NAME_MAX || strchr (name, '/') != NULL)
- {
- __set_errno (EINVAL);
- return -1;
- }
-
- fname = (char *) alloca (mountpoint.dirlen + namelen + 1);
- __mempcpy (__mempcpy (fname, mountpoint.dir, mountpoint.dirlen),
- name, namelen + 1);
-
- /* And get the file descriptor.
- XXX Maybe we should test each descriptor whether it really is for a
- file on the shmfs. If this is what should be done the whole function
- should be revamped since we can determine whether shmfs is available
- while trying to open the file, all in one turn. */
- fd = open (fname, oflag | O_CLOEXEC | O_NOFOLLOW, mode);
- if (fd == -1 && __glibc_unlikely (errno == EISDIR))
- /* It might be better to fold this error with EINVAL since
- directory names are just another example for unsuitable shared
- object names and the standard does not mention EISDIR. */
- __set_errno (EINVAL);
-
- return fd;
-}
-
-
-/* Unlink a shared memory object. */
-int
-shm_unlink (const char *name)
-{
- size_t namelen;
- char *fname;
-
- /* Determine where the shmfs is mounted. */
- __libc_once (once, where_is_shmfs);
-
- if (mountpoint.dir == NULL)
- {
- /* We cannot find the shmfs. If `name' is really a shared
- memory object it must have been created by another process
- and we have no idea where that process found the mountpoint. */
- __set_errno (ENOENT);
- return -1;
- }
-
- /* Construct the filename. */
- while (name[0] == '/')
- ++name;
-
- namelen = strlen (name);
-
- /* Validate the filename. */
- if (name[0] == '\0' || namelen > NAME_MAX || strchr (name, '/') != NULL)
- {
- __set_errno (ENOENT);
- return -1;
- }
-
- fname = (char *) alloca (mountpoint.dirlen + namelen + 1);
- __mempcpy (__mempcpy (fname, mountpoint.dir, mountpoint.dirlen),
- name, namelen + 1);
-
- /* And remove the file. */
- int ret = unlink (fname);
- if (ret < 0 && errno == EPERM)
- __set_errno (EACCES);
- return ret;
-}
-
-
-/* Make sure the table is freed if we want to free everything before
- exiting. */
-libc_freeres_fn (freeit)
-{
- if (mountpoint.dir != defaultdir)
- free (mountpoint.dir);
-}
deleted file mode 100644
@@ -1 +0,0 @@
-/* This function is for technical reason defined in shm_open.c. */