Updated to fedora-glibc-20080728T2320
[glibc.git] / hurd / dtable.c
blob125345e6e31003774303ebc1fb17168952989347
1 /* Copyright (C) 1991,92,93,94,95,96,97,99 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, write to the Free
16 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
17 02111-1307 USA. */
19 #include <hurd.h>
20 #include <hurd/term.h>
21 #include <hurd/fd.h>
22 #include <stdlib.h>
23 #include <stdio.h>
24 #include <fcntl.h>
25 #include <limits.h>
26 #include <cthreads.h> /* For `struct mutex'. */
27 #include "set-hooks.h"
28 #include "hurdmalloc.h" /* XXX */
31 struct mutex _hurd_dtable_lock = MUTEX_INITIALIZER; /* XXX ld bug; must init */
32 struct hurd_fd **_hurd_dtable;
33 int _hurd_dtablesize;
36 DEFINE_HOOK (_hurd_fd_subinit, (void));
38 /* Initialize the file descriptor table at startup. */
40 static void
41 init_dtable (void)
43 int i;
45 __mutex_init (&_hurd_dtable_lock);
47 /* The initial size of the descriptor table is that of the passed-in
48 table. It will be expanded as necessary up to _hurd_dtable_rlimit. */
49 _hurd_dtablesize = _hurd_init_dtablesize;
51 /* Allocate the vector of pointers. */
52 _hurd_dtable = malloc (_hurd_dtablesize * sizeof (*_hurd_dtable));
53 if (_hurd_dtablesize != 0 && _hurd_dtable == NULL)
54 __libc_fatal ("hurd: Can't allocate file descriptor table\n");
56 /* Initialize the descriptor table. */
57 for (i = 0; (unsigned int) i < _hurd_init_dtablesize; ++i)
59 if (_hurd_init_dtable[i] == MACH_PORT_NULL)
60 /* An unused descriptor is marked by a null pointer. */
61 _hurd_dtable[i] = NULL;
62 else
64 /* Allocate a new file descriptor structure. */
65 struct hurd_fd *new = malloc (sizeof (struct hurd_fd));
66 if (new == NULL)
67 __libc_fatal ("hurd: Can't allocate initial file descriptors\n");
69 /* Initialize the port cells. */
70 _hurd_port_init (&new->port, MACH_PORT_NULL);
71 _hurd_port_init (&new->ctty, MACH_PORT_NULL);
73 /* Install the port in the descriptor.
74 This sets up all the ctty magic. */
75 _hurd_port2fd (new, _hurd_init_dtable[i], 0);
77 _hurd_dtable[i] = new;
81 /* Clear out the initial descriptor table.
82 Everything must use _hurd_dtable now. */
83 __vm_deallocate (__mach_task_self (),
84 (vm_address_t) _hurd_init_dtable,
85 _hurd_init_dtablesize * sizeof (_hurd_init_dtable[0]));
86 _hurd_init_dtable = NULL;
87 _hurd_init_dtablesize = 0;
89 /* Initialize the remaining empty slots in the table. */
90 for (; i < _hurd_dtablesize; ++i)
91 _hurd_dtable[i] = NULL;
93 /* Run things that want to run after the file descriptor table
94 is initialized. */
95 RUN_HOOK (_hurd_fd_subinit, ());
97 (void) &init_dtable; /* Avoid "defined but not used" warning. */
100 text_set_element (_hurd_subinit, init_dtable);
102 /* XXX when the linker supports it, the following functions should all be
103 elsewhere and just have text_set_elements here. */
105 /* Called by `getdport' to do its work. */
107 static file_t
108 get_dtable_port (int fd)
110 struct hurd_fd *d = _hurd_fd_get (fd);
111 file_t dport;
113 if (!d)
114 return __hurd_fail (EBADF), MACH_PORT_NULL;
116 HURD_CRITICAL_BEGIN;
118 dport = HURD_PORT_USE (&d->port,
120 error_t err;
121 mach_port_t outport;
122 err = __mach_port_mod_refs (__mach_task_self (),
123 port,
124 MACH_PORT_RIGHT_SEND,
126 if (err)
128 errno = err;
129 outport = MACH_PORT_NULL;
131 else
132 outport = port;
133 outport;
134 }));
136 HURD_CRITICAL_END;
138 return dport;
141 file_t (*_hurd_getdport_fn) (int fd) = get_dtable_port;
143 #include <hurd/signal.h>
145 /* We are in the child fork; the dtable lock is still held.
146 The parent has inserted send rights for all the normal io ports,
147 but we must recover ctty-special ports for ourselves. */
148 static error_t
149 fork_child_dtable (void)
151 error_t err;
152 int i;
154 err = 0;
156 for (i = 0; !err && i < _hurd_dtablesize; ++i)
158 struct hurd_fd *d = _hurd_dtable[i];
159 if (d == NULL)
160 continue;
162 /* No other thread is using the send rights in the child task. */
163 d->port.users = d->ctty.users = NULL;
165 if (d->ctty.port != MACH_PORT_NULL)
167 /* There was a ctty-special port in the parent.
168 We need to get one for ourselves too. */
169 __mach_port_deallocate (__mach_task_self (), d->ctty.port);
170 err = __term_open_ctty (d->port.port, _hurd_pid, _hurd_pgrp,
171 &d->ctty.port);
172 if (err)
173 d->ctty.port = MACH_PORT_NULL;
176 /* XXX for each fd with a cntlmap, reauth and re-map_cntl. */
178 return err;
180 (void) &fork_child_dtable; /* Avoid "defined but not used" warning. */
183 data_set_element (_hurd_fork_locks, _hurd_dtable_lock); /* XXX ld bug: bss */
184 text_set_element (_hurd_fork_child_hook, fork_child_dtable);
186 /* Called when our process group has changed. */
188 static void
189 ctty_new_pgrp (void)
191 int i;
193 HURD_CRITICAL_BEGIN;
194 __mutex_lock (&_hurd_dtable_lock);
196 if (__USEPORT (CTTYID, port == MACH_PORT_NULL))
198 /* We have no controlling terminal. If we haven't had one recently,
199 but our pgrp is being pointlessly diddled anyway, then we will
200 have nothing to do in the loop below because no fd will have a
201 ctty port at all.
203 More likely, a setsid call is responsible both for the change
204 in pgrp and for clearing the cttyid port. In that case, setsid
205 held the dtable lock while updating the dtable to clear all the
206 ctty ports, and ergo must have finished doing so before we run here.
207 So we can be sure, again, that the loop below has no work to do. */
209 else
210 for (i = 0; i < _hurd_dtablesize; ++i)
212 struct hurd_fd *const d = _hurd_dtable[i];
213 struct hurd_userlink ulink, ctty_ulink;
214 io_t port, ctty;
216 if (d == NULL)
217 /* Nothing to do for an unused descriptor cell. */
218 continue;
220 port = _hurd_port_get (&d->port, &ulink);
221 ctty = _hurd_port_get (&d->ctty, &ctty_ulink);
223 if (ctty != MACH_PORT_NULL)
225 /* This fd has a ctty-special port. We need a new one, to tell
226 the io server of our different process group. */
227 io_t new;
228 if (__term_open_ctty (port, _hurd_pid, _hurd_pgrp, &new))
229 new = MACH_PORT_NULL;
230 _hurd_port_set (&d->ctty, new);
233 _hurd_port_free (&d->port, &ulink, port);
234 _hurd_port_free (&d->ctty, &ctty_ulink, ctty);
237 __mutex_unlock (&_hurd_dtable_lock);
238 HURD_CRITICAL_END;
240 (void) &ctty_new_pgrp; /* Avoid "defined but not used" warning. */
243 text_set_element (_hurd_pgrp_changed_hook, ctty_new_pgrp);
245 /* Called to reauthenticate the dtable when the auth port changes. */
247 static void
248 reauth_dtable (void)
250 int i;
252 HURD_CRITICAL_BEGIN;
253 __mutex_lock (&_hurd_dtable_lock);
255 for (i = 0; i < _hurd_dtablesize; ++i)
257 struct hurd_fd *const d = _hurd_dtable[i];
258 mach_port_t new, newctty, ref;
260 if (d == NULL)
261 /* Nothing to do for an unused descriptor cell. */
262 continue;
264 ref = __mach_reply_port ();
266 /* Take the descriptor cell's lock. */
267 __spin_lock (&d->port.lock);
269 /* Reauthenticate the descriptor's port. */
270 if (d->port.port != MACH_PORT_NULL &&
271 ! __io_reauthenticate (d->port.port,
272 ref, MACH_MSG_TYPE_MAKE_SEND) &&
273 ! __USEPORT (AUTH, __auth_user_authenticate
274 (port,
275 ref, MACH_MSG_TYPE_MAKE_SEND,
276 &new)))
278 /* Replace the port in the descriptor cell
279 with the newly reauthenticated port. */
281 if (d->ctty.port != MACH_PORT_NULL &&
282 ! __io_reauthenticate (d->ctty.port,
283 ref, MACH_MSG_TYPE_MAKE_SEND) &&
284 ! __USEPORT (AUTH, __auth_user_authenticate
285 (port,
286 ref, MACH_MSG_TYPE_MAKE_SEND,
287 &newctty)))
288 _hurd_port_set (&d->ctty, newctty);
290 _hurd_port_locked_set (&d->port, new);
292 else
293 /* Lost. Leave this descriptor cell alone. */
294 __spin_unlock (&d->port.lock);
296 __mach_port_destroy (__mach_task_self (), ref);
299 __mutex_unlock (&_hurd_dtable_lock);
300 HURD_CRITICAL_END;
302 (void) &reauth_dtable; /* Avoid "defined but not used" warning. */
305 text_set_element (_hurd_reauth_hook, reauth_dtable);