1 | /* Copyright (C) 1991-2022 Free Software Foundation, Inc. |
2 | |
3 | This file is part of the GNU C Library. |
4 | |
5 | The GNU C Library is free software; you can redistribute it and/or |
6 | modify it under the terms of the GNU Lesser General Public |
7 | License as published by the Free Software Foundation; either |
8 | version 2.1 of the License, or (at your option) any later version. |
9 | |
10 | The GNU C Library is distributed in the hope that it will be useful, |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
13 | Lesser General Public License for more details. |
14 | |
15 | You should have received a copy of the GNU Lesser General Public |
16 | License along with the GNU C Library; if not, see |
17 | <https://www.gnu.org/licenses/>. */ |
18 | |
19 | #include <errno.h> |
20 | #include <hurd.h> |
21 | #include <hurd/signal.h> |
22 | #include <hurd/msg.h> |
23 | #include <sysdep-cancel.h> |
24 | |
25 | /* Change the set of blocked signals to SET, |
26 | wait until a signal arrives, and restore the set of blocked signals. */ |
27 | int |
28 | __sigsuspend (const sigset_t *set) |
29 | { |
30 | struct hurd_sigstate *ss; |
31 | sigset_t newmask, oldmask, pending; |
32 | mach_port_t wait; |
33 | mach_msg_header_t msg; |
34 | int cancel_oldtype; |
35 | |
36 | if (set != NULL) |
37 | /* Crash before locking. */ |
38 | newmask = *set; |
39 | |
40 | /* Get a fresh port we will wait on. */ |
41 | wait = __mach_reply_port (); |
42 | |
43 | ss = _hurd_self_sigstate (); |
44 | |
45 | _hurd_sigstate_lock (ss); |
46 | |
47 | oldmask = ss->blocked; |
48 | if (set != NULL) |
49 | /* Change to the new blocked signal mask. */ |
50 | ss->blocked = newmask & ~_SIG_CANT_MASK; |
51 | |
52 | /* Notice if any pending signals just became unblocked. */ |
53 | pending = _hurd_sigstate_pending (ss) & ~ss->blocked; |
54 | |
55 | /* Tell the signal thread to message us when a signal arrives. */ |
56 | ss->suspended = wait; |
57 | _hurd_sigstate_unlock (ss); |
58 | |
59 | if (pending) |
60 | /* Tell the signal thread to check for pending signals. */ |
61 | __msg_sig_post (_hurd_msgport, 0, 0, __mach_task_self ()); |
62 | |
63 | /* Wait for the signal thread's message. */ |
64 | |
65 | cancel_oldtype = LIBC_CANCEL_ASYNC(); |
66 | __mach_msg (&msg, MACH_RCV_MSG, 0, sizeof (msg), wait, |
67 | MACH_MSG_TIMEOUT_NONE, MACH_PORT_NULL); |
68 | LIBC_CANCEL_RESET (cancel_oldtype); |
69 | __mach_port_destroy (__mach_task_self (), wait); |
70 | |
71 | /* Restore the old mask and check for pending signals again. */ |
72 | _hurd_sigstate_lock (ss); |
73 | ss->blocked = oldmask; |
74 | pending = _hurd_sigstate_pending(ss) & ~ss->blocked; |
75 | _hurd_sigstate_unlock (ss); |
76 | |
77 | if (pending) |
78 | /* Tell the signal thread to check for pending signals. */ |
79 | __msg_sig_post (_hurd_msgport, 0, 0, __mach_task_self ()); |
80 | |
81 | /* We've been interrupted! And a good thing, too. |
82 | Otherwise we'd never return. |
83 | That's right; this function always returns an error. */ |
84 | errno = EINTR; |
85 | return -1; |
86 | } |
87 | libc_hidden_def (__sigsuspend) |
88 | weak_alias (__sigsuspend, sigsuspend) |
89 | |