diff options
Diffstat (limited to 'trans/symlink.c')
| -rw-r--r-- | trans/symlink.c | 236 |
1 files changed, 236 insertions, 0 deletions
diff --git a/trans/symlink.c b/trans/symlink.c new file mode 100644 index 00000000..845a1121 --- /dev/null +++ b/trans/symlink.c @@ -0,0 +1,236 @@ +/* Translator for S_IFLNK nodes + Copyright (C) 1994, 2000, 2001, 2002 Free Software Foundation + + 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 <hurd.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <argp.h> +#include <hurd/fsys.h> +#include <fcntl.h> +#include <errno.h> +#include <error.h> +#include <version.h> +#include "fsys_S.h" + +mach_port_t realnode; + +/* We return this for O_NOLINK lookups */ +mach_port_t realnodenoauth; + +/* We return this for non O_NOLINK lookups */ +char *linktarget; + +extern int fsys_server (mach_msg_header_t *, mach_msg_header_t *); + +const char *argp_program_version = STANDARD_HURD_VERSION (symlink); + +static const struct argp_option options[] = + { + { 0 } + }; + +static const char args_doc[] = "TARGET"; +static const char doc[] = "A translator for symlinks." +"\vA symlink is an alias for another node in the filesystem." +"\n" +"\nA symbolic link refers to its target `by name', and contains no actual" +" reference to the target. The target referenced by the symlink is" +" looked up in the namespace of the client."; + +/* Parse a single option/argument. */ +static error_t +parse_opt (int key, char *arg, struct argp_state *state) +{ + if (key == ARGP_KEY_ARG && state->arg_num == 0) + linktarget = arg; + else if (key == ARGP_KEY_ARG || key == ARGP_KEY_NO_ARGS) + argp_usage (state); + else + return ARGP_ERR_UNKNOWN; + return 0; +} + +static struct argp argp = { options, parse_opt, args_doc, doc }; + + +int +main (int argc, char **argv) +{ + mach_port_t bootstrap; + mach_port_t control; + error_t err; + + /* Parse our options... */ + argp_parse (&argp, argc, argv, 0, 0, 0); + + task_get_bootstrap_port (mach_task_self (), &bootstrap); + if (bootstrap == MACH_PORT_NULL) + error (1, 0, "Must be started as a translator"); + + linktarget = argv[1]; + + /* Reply to our parent */ + mach_port_allocate (mach_task_self (), MACH_PORT_RIGHT_RECEIVE, &control); + mach_port_insert_right (mach_task_self (), control, control, + MACH_MSG_TYPE_MAKE_SEND); + err = + fsys_startup (bootstrap, 0, control, MACH_MSG_TYPE_COPY_SEND, &realnode); + mach_port_deallocate (mach_task_self (), control); + mach_port_deallocate (mach_task_self (), bootstrap); + if (err) + error (1, err, "Starting up translator"); + + io_restrict_auth (realnode, &realnodenoauth, 0, 0, 0, 0); + mach_port_deallocate (mach_task_self (), realnode); + + /* Mark us as important. */ + mach_port_t proc = getproc (); + if (proc == MACH_PORT_NULL) + error (2, err, "cannot get a handle to our process"); + + err = proc_mark_important (proc); + /* This might fail due to permissions or because the old proc server + is still running, ignore any such errors. */ + if (err && err != EPERM && err != EMIG_BAD_ID) + error (2, err, "Cannot mark us as important"); + + mach_port_deallocate (mach_task_self (), proc); + + /* Launch */ + while (1) + { + /* The timeout here is 10 minutes */ + err = mach_msg_server_timeout (fsys_server, 0, control, + MACH_RCV_TIMEOUT, 1000 * 60 * 10); + if (err == MACH_RCV_TIMED_OUT) + exit (0); + } +} + +error_t +S_fsys_getroot (mach_port_t fsys_t, + mach_port_t dotdotnode, + uid_t *uids, size_t nuids, + uid_t *gids, size_t ngids, + int flags, + retry_type *do_retry, + char *retry_name, + mach_port_t *ret, + mach_msg_type_name_t *rettype) +{ + if (flags & O_NOLINK) + { + /* Return our underlying node. */ + *ret = realnodenoauth; + *rettype = MACH_MSG_TYPE_COPY_SEND; + *do_retry = FS_RETRY_REAUTH; + retry_name[0] = '\0'; + return 0; + } + else + { + /* Return telling the user to follow the link */ + strcpy (retry_name, linktarget); + if (linktarget[0] == '/') + { + *do_retry = FS_RETRY_MAGICAL; + *ret = MACH_PORT_NULL; + *rettype = MACH_MSG_TYPE_COPY_SEND; + } + else + { + *do_retry = FS_RETRY_REAUTH; + *ret = dotdotnode; + *rettype = MACH_MSG_TYPE_MOVE_SEND; + } + } + return 0; +} + +error_t +S_fsys_startup (mach_port_t bootstrap, int flags, mach_port_t control, + mach_port_t *real, mach_msg_type_name_t *realtype) +{ + return EOPNOTSUPP; +} + +error_t +S_fsys_goaway (mach_port_t control, int flags) +{ + exit (0); +} + +error_t +S_fsys_syncfs (mach_port_t control, + int wait, + int recurse) +{ + return 0; +} + +error_t +S_fsys_set_options (mach_port_t control, + char *data, mach_msg_type_number_t len, + int do_children) +{ + return EOPNOTSUPP; +} + +error_t +S_fsys_get_options (mach_port_t control, + char **data, mach_msg_type_number_t *len) +{ + return EOPNOTSUPP; +} + +error_t +S_fsys_getfile (mach_port_t control, + uid_t *uids, size_t nuids, + uid_t *gids, size_t ngids, + char *handle, size_t handllen, + mach_port_t *pt, + mach_msg_type_name_t *pttype) +{ + return EOPNOTSUPP; +} + +error_t +S_fsys_getpriv (mach_port_t control, + mach_port_t *host_priv, mach_msg_type_name_t *host_priv_type, + mach_port_t *dev_master, mach_msg_type_name_t *dev_master_type, + task_t *fs_task, mach_msg_type_name_t *fs_task_type) +{ + return EOPNOTSUPP; +} + +error_t +S_fsys_init (mach_port_t control, + mach_port_t reply, + mach_msg_type_name_t replytype, + mach_port_t proc, + auth_t auth) +{ + return EOPNOTSUPP; +} + +error_t +S_fsys_forward (mach_port_t server, mach_port_t requestor, + char *argz, size_t argz_len) +{ + return EOPNOTSUPP; +} |