static void set_startloc(
rtems_filesystem_eval_path_context_t *ctx,
rtems_filesystem_global_location_t *const *global_root_ptr,
rtems_filesystem_global_location_t *const *global_current_ptr
)
{
if (ctx->pathlen > 0) {
char c = ctx->path [0];
ctx->rootloc = rtems_filesystem_global_location_obtain(global_root_ptr);
if (rtems_filesystem_is_delimiter(c)) {
++ctx->path;
--ctx->pathlen;
ctx->startloc = rtems_filesystem_global_location_obtain(
&ctx->rootloc
);
} else {
ctx->startloc = rtems_filesystem_global_location_obtain(
global_current_ptr
);
}
} else {
ctx->rootloc = rtems_filesystem_global_location_obtain_null();
ctx->startloc = rtems_filesystem_global_location_obtain_null();
errno = ENOENT;
}
}
void rtems_filesystem_eval_path_restart(
rtems_filesystem_eval_path_context_t *ctx,
rtems_filesystem_global_location_t **newstartloc_ptr
)
{
free_location(&ctx->currentloc);
rtems_filesystem_instance_unlock(&ctx->startloc->location);
rtems_filesystem_global_location_assign(
&ctx->startloc,
rtems_filesystem_global_location_obtain(newstartloc_ptr)
);
rtems_filesystem_instance_lock(&ctx->startloc->location);
rtems_filesystem_location_clone(&ctx->currentloc, &ctx->startloc->location);
}
static int register_root_file_system(
rtems_filesystem_mount_table_entry_t *mt_entry
)
{
int rv = 0;
rtems_filesystem_mt_lock();
if ( rtems_chain_is_empty( &rtems_filesystem_mount_table ) ) {
rtems_chain_append_unprotected(
&rtems_filesystem_mount_table,
&mt_entry->mt_node
);
} else {
errno = EINVAL;
rv = -1;
}
rtems_filesystem_mt_unlock();
if ( rv == 0 ) {
rtems_filesystem_global_location_t *new_fs_root =
rtems_filesystem_global_location_obtain( &mt_entry->mt_fs_root );
rtems_filesystem_global_location_t *new_fs_current =
rtems_filesystem_global_location_obtain( &mt_entry->mt_fs_root );
rtems_filesystem_global_location_assign(
&rtems_filesystem_root,
new_fs_root
);
rtems_filesystem_global_location_assign(
&rtems_filesystem_current,
new_fs_current
);
}
return rv;
}
int chroot( const char *path )
{
int rv = 0;
rtems_status_code sc = RTEMS_SUCCESSFUL;
rtems_filesystem_eval_path_context_t ctx;
int eval_flags = RTEMS_FS_PERMS_EXEC
| RTEMS_FS_FOLLOW_LINK;
rtems_filesystem_location_info_t loc;
rtems_filesystem_global_location_t *new_current_loc;
/*
* We use the global environment for path evaluation. This makes it possible
* to escape from a chroot environment referencing an unmounted file system.
*/
rtems_filesystem_eval_path_start_with_root_and_current(
&ctx,
path,
eval_flags,
&rtems_global_user_env.root_directory,
&rtems_global_user_env.current_directory
);
rtems_filesystem_eval_path_extract_currentloc( &ctx, &loc );
new_current_loc = rtems_filesystem_location_transform_to_global( &loc );
if ( !rtems_filesystem_global_location_is_null( new_current_loc ) ) {
rtems_filesystem_global_location_t *new_root_loc =
rtems_filesystem_global_location_obtain( &new_current_loc );
rtems_filesystem_node_types_t type =
(*new_root_loc->location.mt_entry->ops->node_type_h)(
&new_root_loc->location
);
if ( type == RTEMS_FILESYSTEM_DIRECTORY ) {
sc = rtems_libio_set_private_env();
if (sc == RTEMS_SUCCESSFUL) {
rtems_filesystem_global_location_assign(
&rtems_filesystem_root,
new_root_loc
);
rtems_filesystem_global_location_assign(
&rtems_filesystem_current,
new_current_loc
);
} else {
if (sc != RTEMS_UNSATISFIED) {
errno = ENOMEM;
}
rv = -1;
}
} else {
rtems_filesystem_location_error( &new_root_loc->location, ENOTDIR );
rv = -1;
}
if ( rv != 0 ) {
rtems_filesystem_global_location_release( new_root_loc );
}
} else {
rv = -1;
}
rtems_filesystem_eval_path_cleanup( &ctx );
if ( rv != 0 ) {
rtems_filesystem_global_location_release( new_current_loc );
}
return rv;
}
