1 /* Copyright (C) 2002-2022 Free Software Foundation, Inc.
2    This file is part of the GNU C Library.
3 
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.
8 
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.
13 
14    You should have received a copy of the GNU Lesser General Public
15    License along with the GNU C Library; if not, see
16    <https://www.gnu.org/licenses/>.  */
17 
18 #include <stdlib.h>
19 #include "pthreadP.h"
20 #include <shlib-compat.h>
21 
22 void
23 __cleanup_fct_attribute
___pthread_register_cancel_defer(__pthread_unwind_buf_t * buf)24 ___pthread_register_cancel_defer (__pthread_unwind_buf_t *buf)
25 {
26   struct pthread_unwind_buf *ibuf = (struct pthread_unwind_buf *) buf;
27   struct pthread *self = THREAD_SELF;
28 
29   /* Store old info.  */
30   ibuf->priv.data.prev = THREAD_GETMEM (self, cleanup_jmp_buf);
31   ibuf->priv.data.cleanup = THREAD_GETMEM (self, cleanup);
32 
33   int cancelhandling = atomic_load_relaxed (&self->cancelhandling);
34   if (__glibc_unlikely (cancelhandling & CANCELTYPE_BITMASK))
35     {
36       int newval;
37       do
38 	{
39 	  newval = cancelhandling & ~CANCELTYPE_BITMASK;
40 	}
41       while (!atomic_compare_exchange_weak_acquire (&self->cancelhandling,
42 						    &cancelhandling,
43 						    newval));
44     }
45 
46   ibuf->priv.data.canceltype = (cancelhandling & CANCELTYPE_BITMASK
47 				? PTHREAD_CANCEL_ASYNCHRONOUS
48 				: PTHREAD_CANCEL_DEFERRED);
49 
50   /* Store the new cleanup handler info.  */
51   THREAD_SETMEM (self, cleanup_jmp_buf, (struct pthread_unwind_buf *) buf);
52 }
53 versioned_symbol (libc, ___pthread_register_cancel_defer,
54 		  __pthread_register_cancel_defer, GLIBC_2_34);
55 
56 #if OTHER_SHLIB_COMPAT (libpthread, GLIBC_2_3_3, GLIBC_2_34)
57 compat_symbol (libpthread, ___pthread_register_cancel_defer,
58 	       __pthread_register_cancel_defer, GLIBC_2_3_3);
59 #endif
60 
61 void
62 __cleanup_fct_attribute
___pthread_unregister_cancel_restore(__pthread_unwind_buf_t * buf)63 ___pthread_unregister_cancel_restore (__pthread_unwind_buf_t *buf)
64 {
65   struct pthread *self = THREAD_SELF;
66   struct pthread_unwind_buf *ibuf = (struct pthread_unwind_buf *) buf;
67 
68   THREAD_SETMEM (self, cleanup_jmp_buf, ibuf->priv.data.prev);
69 
70   if (ibuf->priv.data.canceltype == PTHREAD_CANCEL_DEFERRED)
71     return;
72 
73   int cancelhandling = atomic_load_relaxed (&self->cancelhandling);
74   if ((cancelhandling & CANCELTYPE_BITMASK) == 0)
75     {
76       int newval;
77       do
78 	{
79 	  newval = cancelhandling | CANCELTYPE_BITMASK;
80 	}
81       while (!atomic_compare_exchange_weak_acquire (&self->cancelhandling,
82 						    &cancelhandling, newval));
83 
84       if (cancel_enabled_and_canceled (cancelhandling))
85 	{
86 	  self->result = PTHREAD_CANCELED;
87 	  __do_cancel ();
88 	}
89     }
90 }
91 versioned_symbol (libc, ___pthread_unregister_cancel_restore,
92 		  __pthread_unregister_cancel_restore, GLIBC_2_34);
93 
94 #if OTHER_SHLIB_COMPAT (libpthread, GLIBC_2_3_3, GLIBC_2_34)
95 compat_symbol (libpthread, ___pthread_unregister_cancel_restore,
96 	       __pthread_unregister_cancel_restore, GLIBC_2_3_3);
97 #endif
98