Warning: That file was not part of the compilation database. It may have many parsing errors.

1/* Thread cancellation support.
2 Copyright (C) 1995-2019 Free Software Foundation, Inc.
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 <http://www.gnu.org/licenses/>. */
18
19#include <hurd/signal.h>
20#include <hurd/interrupt.h>
21#include <assert.h>
22#include <thread_state.h>
23
24
25/* See hurdsig.c. */
26extern mach_port_t _hurdsig_abort_rpcs (struct hurd_sigstate *ss,
27 int signo, int sigthread,
28 struct machine_thread_all_state *,
29 int *state_change,
30 mach_port_t *reply_port,
31 mach_msg_type_name_t reply_port_type,
32 int untraced);
33
34error_t
35hurd_thread_cancel (thread_t thread)
36{
37 struct hurd_sigstate *ss = _hurd_thread_sigstate (thread);
38 struct machine_thread_all_state state;
39 int state_change;
40 error_t err;
41
42 if (! ss)
43 return EINVAL;
44 if (ss == _hurd_self_sigstate ())
45 {
46 /* We are cancelling ourselves, so it is easy to succeed
47 quickly. Since this function is not a cancellation point, we
48 just leave the flag set pending the next cancellation point
49 (hurd_check_cancel or RPC) and return success. */
50 ss->cancel = 1;
51 return 0;
52 }
53
54 assert (! __spin_lock_locked (&ss->critical_section_lock));
55 __spin_lock (&ss->critical_section_lock);
56 __spin_lock (&ss->lock);
57 err = __thread_suspend (thread);
58 __spin_unlock (&ss->lock);
59
60 if (! err)
61 {
62 /* Set the flag telling the thread its operation is being cancelled. */
63 ss->cancel = 1;
64
65 /* Interrupt any interruptible RPC now in progress. */
66 state.set = 0;
67 _hurdsig_abort_rpcs (ss, 0, 0, &state, &state_change, NULL, 0, 0);
68 if (state_change)
69 err = __thread_set_state (thread, MACHINE_THREAD_STATE_FLAVOR,
70 (natural_t *) &state.basic,
71 MACHINE_THREAD_STATE_COUNT);
72
73 if (ss->cancel_hook)
74 /* The code being cancelled has a special wakeup function.
75 Calling this should make the thread wake up and check the
76 cancellation flag. */
77 (*ss->cancel_hook) ();
78
79 __thread_resume (thread);
80 }
81
82 _hurd_critical_section_unlock (ss);
83 return err;
84}
85
86
87int
88hurd_check_cancel (void)
89{
90 struct hurd_sigstate *ss = _hurd_self_sigstate ();
91 int cancel;
92
93 __spin_lock (&ss->lock);
94 assert (! __spin_lock_locked (&ss->critical_section_lock));
95 cancel = ss->cancel;
96 ss->cancel = 0;
97 __spin_unlock (&ss->lock);
98
99 return cancel;
100}
101

Warning: That file was not part of the compilation database. It may have many parsing errors.