| /* Get file-specific information about a file. Linux version. |
| Copyright (C) 1991,1995,1996,1998-2003,2008,2010 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, write to the Free |
| Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307 USA. */ |
| |
| #include <unistd.h> |
| #include <errno.h> |
| |
| #include "pathconf.h" |
| #include "linux_fsinfo.h" |
| #include <not-cancel.h> |
| |
| static long int posix_pathconf (const char *file, int name); |
| |
| /* Define this first, so it can be inlined. */ |
| #define __pathconf static posix_pathconf |
| #include <sysdeps/posix/pathconf.c> |
| |
| |
| /* Get file-specific information about FILE. */ |
| long int |
| __pathconf (const char *file, int name) |
| { |
| struct statfs fsbuf; |
| |
| switch (name) |
| { |
| case _PC_LINK_MAX: |
| return __statfs_link_max (__statfs (file, &fsbuf), &fsbuf); |
| |
| case _PC_FILESIZEBITS: |
| return __statfs_filesize_max (__statfs (file, &fsbuf), &fsbuf); |
| |
| case _PC_2_SYMLINKS: |
| return __statfs_symlinks (__statfs (file, &fsbuf), &fsbuf); |
| |
| case _PC_CHOWN_RESTRICTED: |
| return __statfs_chown_restricted (__statfs (file, &fsbuf), &fsbuf); |
| |
| default: |
| return posix_pathconf (file, name); |
| } |
| } |
| |
| |
| /* Used like: return statfs_link_max (__statfs (name, &buf), &buf); */ |
| long int |
| __statfs_link_max (int result, const struct statfs *fsbuf) |
| { |
| if (result < 0) |
| { |
| if (errno == ENOSYS) |
| /* Not possible, return the default value. */ |
| return LINUX_LINK_MAX; |
| |
| /* Some error occured. */ |
| return -1; |
| } |
| |
| switch (fsbuf->f_type) |
| { |
| case EXT2_SUPER_MAGIC: |
| return EXT2_LINK_MAX; |
| |
| case MINIX_SUPER_MAGIC: |
| case MINIX_SUPER_MAGIC2: |
| return MINIX_LINK_MAX; |
| |
| case MINIX2_SUPER_MAGIC: |
| case MINIX2_SUPER_MAGIC2: |
| return MINIX2_LINK_MAX; |
| |
| case XENIX_SUPER_MAGIC: |
| return XENIX_LINK_MAX; |
| |
| case SYSV4_SUPER_MAGIC: |
| case SYSV2_SUPER_MAGIC: |
| return SYSV_LINK_MAX; |
| |
| case COH_SUPER_MAGIC: |
| return COH_LINK_MAX; |
| |
| case UFS_MAGIC: |
| case UFS_CIGAM: |
| return UFS_LINK_MAX; |
| |
| case REISERFS_SUPER_MAGIC: |
| return REISERFS_LINK_MAX; |
| |
| case XFS_SUPER_MAGIC: |
| return XFS_LINK_MAX; |
| |
| default: |
| return LINUX_LINK_MAX; |
| } |
| } |
| |
| |
| /* Used like: return statfs_filesize_max (__statfs (name, &buf), &buf); */ |
| long int |
| __statfs_filesize_max (int result, const struct statfs *fsbuf) |
| { |
| if (result < 0) |
| { |
| if (errno == ENOSYS) |
| /* Not possible, return the default value. */ |
| return 32; |
| |
| /* Some error occured. */ |
| return -1; |
| } |
| |
| switch (fsbuf->f_type) |
| { |
| case BTRFS_SUPER_MAGIC: |
| return 255; |
| |
| case EXT2_SUPER_MAGIC: |
| case UFS_MAGIC: |
| case UFS_CIGAM: |
| case REISERFS_SUPER_MAGIC: |
| case XFS_SUPER_MAGIC: |
| case SMB_SUPER_MAGIC: |
| case NTFS_SUPER_MAGIC: |
| case UDF_SUPER_MAGIC: |
| case JFS_SUPER_MAGIC: |
| case VXFS_SUPER_MAGIC: |
| case CGROUP_SUPER_MAGIC: |
| return 64; |
| |
| case MSDOS_SUPER_MAGIC: |
| case JFFS_SUPER_MAGIC: |
| case JFFS2_SUPER_MAGIC: |
| case NCP_SUPER_MAGIC: |
| case ROMFS_SUPER_MAGIC: |
| return 32; |
| |
| default: |
| return 32; |
| } |
| } |
| |
| |
| /* Used like: return statfs_link_max (__statfs (name, &buf), &buf); */ |
| long int |
| __statfs_symlinks (int result, const struct statfs *fsbuf) |
| { |
| if (result < 0) |
| { |
| if (errno == ENOSYS) |
| /* Not possible, return the default value. */ |
| return 1; |
| |
| /* Some error occured. */ |
| return -1; |
| } |
| |
| switch (fsbuf->f_type) |
| { |
| case ADFS_SUPER_MAGIC: |
| case BFS_MAGIC: |
| case CRAMFS_MAGIC: |
| case DEVPTS_SUPER_MAGIC: |
| case EFS_SUPER_MAGIC: |
| case EFS_MAGIC: |
| case MSDOS_SUPER_MAGIC: |
| case NTFS_SUPER_MAGIC: |
| case QNX4_SUPER_MAGIC: |
| case ROMFS_SUPER_MAGIC: |
| /* No symlink support. */ |
| return 0; |
| |
| default: |
| return 1; |
| } |
| } |
| |
| |
| /* Used like: return __statfs_chown_restricted (__statfs (name, &buf), &buf);*/ |
| long int |
| __statfs_chown_restricted (int result, const struct statfs *fsbuf) |
| { |
| if (result < 0) |
| { |
| if (errno == ENOSYS) |
| /* Not possible, return the default value. */ |
| return 1; |
| |
| /* Some error occured. */ |
| return -1; |
| } |
| |
| int fd; |
| long int retval = 1; |
| switch (fsbuf->f_type) |
| { |
| case XFS_SUPER_MAGIC: |
| /* Read the value from /proc/sys/fs/xfs/restrict_chown. If we cannot |
| read it default to assume the restriction is in place. */ |
| fd = open_not_cancel_2 ("/proc/sys/fs/xfs/restrict_chown", O_RDONLY); |
| if (fd != -1) |
| { |
| char buf[2]; |
| if (TEMP_FAILURE_RETRY (read_not_cancel (fd, buf, 2)) == 2 |
| && buf[0] >= '0' && buf[0] <= '1') |
| retval = buf[0] - '0'; |
| |
| close_not_cancel_no_status (fd); |
| } |
| break; |
| |
| default: |
| break; |
| } |
| |
| return retval; |
| } |