diff options
Diffstat (limited to 'libdiskfs/file-set-trans.c')
| -rw-r--r-- | libdiskfs/file-set-trans.c | 209 |
1 files changed, 209 insertions, 0 deletions
diff --git a/libdiskfs/file-set-trans.c b/libdiskfs/file-set-trans.c new file mode 100644 index 00000000..22f42ba9 --- /dev/null +++ b/libdiskfs/file-set-trans.c @@ -0,0 +1,209 @@ +/* libdiskfs implementation of fs.defs: file_set_translator + Copyright (C) 1992, 93, 94, 95, 96, 99 Free Software Foundation, Inc. + + This program is free software; you can redistribute it and/or + modify it under the terms of the GNU General Public License as + published by the Free Software Foundation; either version 2, or (at + your option) any later version. + + This program 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 + General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ + +#include "priv.h" +#include "fs_S.h" +#include <hurd/paths.h> +#include <hurd/fsys.h> + +/* Implement file_set_translator as described in <hurd/fs.defs>. */ +kern_return_t +diskfs_S_file_set_translator (struct protid *cred, + int passive_flags, + int active_flags, + int killtrans_flags, + char *passive, + u_int passivelen, + fsys_t active) +{ + struct node *np; + error_t error; + mach_port_t control = MACH_PORT_NULL; + + if (!cred) + return EOPNOTSUPP; + + if (!(passive_flags & FS_TRANS_SET) && !(active_flags & FS_TRANS_SET)) + return 0; + + if ((passive_flags & FS_TRANS_SET) && diskfs_check_readonly ()) + return EROFS; + + if (passive && passive[passivelen - 1]) + return EINVAL; + + np = cred->po->np; + + mutex_lock (&np->lock); + + error = fshelp_isowner (&np->dn_stat, cred->user); + if (error) + { + mutex_unlock (&np->lock); + return error; + } + + if (active_flags & FS_TRANS_SET) + { + error = fshelp_fetch_control (&np->transbox, &control); + if (error) + { + mutex_unlock (&np->lock); + return error; + } + + if ((control != MACH_PORT_NULL) && ((active_flags & FS_TRANS_EXCL) == 0)) + { + mutex_unlock (&np->lock); + error = fsys_goaway (control, killtrans_flags); + mach_port_deallocate (mach_task_self (), control); + if (error && (error != MIG_SERVER_DIED) + && (error != MACH_SEND_INVALID_DEST)) + return error; + error = 0; + mutex_lock (&np->lock); + } + else if (control != MACH_PORT_NULL) + mach_port_deallocate (mach_task_self (), control); + } + + /* Handle exclusive passive bit *first*. */ + if ((passive_flags & FS_TRANS_SET) + && (passive_flags & FS_TRANS_EXCL) + && (np->dn_stat.st_mode & S_IPTRANS)) + { + mutex_unlock (&np->lock); + return EBUSY; + } + + if (active_flags & FS_TRANS_SET) + { + error = fshelp_set_active (&np->transbox, active, + active_flags & FS_TRANS_EXCL); + if (error) + { + mutex_unlock (&np->lock); + return error; + } + } + + /* Set passive translator */ + if (passive_flags & FS_TRANS_SET) + { + if (!(passive_flags & FS_TRANS_FORCE)) + { + /* Handle the short-circuited translators */ + mode_t newmode = 0; + + if (diskfs_shortcut_symlink && !strcmp (passive, _HURD_SYMLINK)) + newmode = S_IFLNK; + else if (diskfs_shortcut_chrdev && !(strcmp (passive, _HURD_CHRDEV))) + newmode = S_IFCHR; + else if (diskfs_shortcut_blkdev && !strcmp (passive, _HURD_BLKDEV)) + newmode = S_IFBLK; + else if (diskfs_shortcut_fifo && !strcmp (passive, _HURD_FIFO)) + newmode = S_IFIFO; + else if (diskfs_shortcut_ifsock && !strcmp (passive, _HURD_IFSOCK)) + newmode = S_IFSOCK; + + if (newmode) + { + if (S_ISDIR (np->dn_stat.st_mode)) + { + /* We can't allow this, because if the mode of the directory + changes, the links will be lost. Perhaps it might be + allowed for empty directories, but that's too much of a + pain. */ + mutex_unlock (&np->lock); + return EISDIR; + } + if (newmode == S_IFBLK || newmode == S_IFCHR) + { + /* Find the device number from the arguments + of the translator. */ + int major, minor; + char *arg; + + arg = passive + strlen (passive) + 1; + assert (arg <= passive + passivelen); + if (arg == passive + passivelen) + { + mutex_unlock (&np->lock); + return EINVAL; + } + major = strtol (arg, 0, 0); + + arg = arg + strlen (arg) + 1; + assert (arg < passive + passivelen); + if (arg == passive + passivelen) + { + mutex_unlock (&np->lock); + return EINVAL; + } + minor = strtol (arg, 0, 0); + + error = diskfs_validate_rdev_change (np, + makedev (major, minor)); + if (error) + { + mutex_unlock (&np->lock); + return error; + } + np->dn_stat.st_rdev = makedev (major, minor); + } + + diskfs_truncate (np, 0); + if (newmode == S_IFLNK) + { + char *arg = passive + strlen (passive) + 1; + assert (arg <= passive + passivelen); + if (arg == passive + passivelen) + { + mutex_unlock (&np->lock); + return EINVAL; + } + + if (diskfs_create_symlink_hook) + error = (*diskfs_create_symlink_hook)(np, arg); + if (!diskfs_create_symlink_hook || error == EINVAL) + /* Store the argument in the file as the + target of the link */ + error = diskfs_node_rdwr (np, arg, 0, strlen (arg), + 1, cred, 0); + if (error) + { + mutex_unlock (&np->lock); + return error; + } + } + newmode = (np->dn_stat.st_mode & ~S_IFMT) | newmode; + error = diskfs_validate_mode_change (np, newmode); + if (!error) + { + np->dn_stat.st_mode = newmode; + diskfs_node_update (np, 1); + } + mutex_unlock (&np->lock); + return error; + } + } + error = diskfs_set_translator (np, passive, passivelen, cred); + } + + mutex_unlock (&np->lock); + return error; +} |