xref: /openbsd/lib/librthread/rthread_np.c (revision cef5a146)
1 /*	$OpenBSD: rthread_np.c,v 1.24 2023/01/07 05:24:58 guenther Exp $	*/
2 /*
3  * Copyright (c) 2004,2005 Ted Unangst <tedu@openbsd.org>
4  * Copyright (c) 2005 Otto Moerbeek <otto@openbsd.org>
5  * All Rights Reserved.
6  *
7  * Permission to use, copy, modify, and distribute this software for any
8  * purpose with or without fee is hereby granted, provided that the above
9  * copyright notice and this permission notice appear in all copies.
10  *
11  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18  */
19 
20 #include <sys/types.h>
21 #include <sys/time.h>
22 #include <sys/lock.h>
23 #include <sys/resource.h>
24 #include <sys/queue.h>
25 #include <sys/sysctl.h>
26 
27 #include <errno.h>
28 #include <pthread.h>
29 #include <pthread_np.h>
30 #include <stddef.h>
31 #include <stdint.h>
32 #include <string.h>
33 #include <tib.h>
34 #include <unistd.h>
35 
36 #include "rthread.h"
37 
38 REDIRECT_SYSCALL(sysctl);
39 REDIRECT_SYSCALL(getthrname);
40 REDIRECT_SYSCALL(setthrname);
41 
42 void
pthread_set_name_np(pthread_t thread,const char * name)43 pthread_set_name_np(pthread_t thread, const char *name)
44 {
45 	pid_t tid = 0;
46 
47 	if (thread != pthread_self())
48 		tid = thread->tib->tib_tid;
49 	setthrname(tid, name);
50 }
51 
52 void
pthread_get_name_np(pthread_t thread,char * name,size_t len)53 pthread_get_name_np(pthread_t thread, char *name, size_t len)
54 {
55 	pid_t tid = 0;
56 
57 	if (thread != pthread_self())
58 		tid = thread->tib->tib_tid;
59 	getthrname(tid, name, len);
60 }
61 
62 int
pthread_main_np(void)63 pthread_main_np(void)
64 {
65 	return (!_threads_ready ||
66 	    (TIB_GET()->tib_thread_flags & TIB_THREAD_INITIAL_STACK) ? 1 : 0);
67 }
68 
69 
70 /*
71  * Return stack info from the given thread.  Based upon the solaris
72  * thr_stksegment function.  Note that the returned ss_sp member is the
73  * *top* of the allocated stack area, unlike in sigaltstack() where
74  * it's the bottom.  You'll have to ask Sun what they were thinking...
75  *
76  * This function taken from the uthread library, with the following
77  * license:
78  * PUBLIC DOMAIN: No Rights Reserved. Marco S Hyman <marc@snafu.org> */
79 int
pthread_stackseg_np(pthread_t thread,stack_t * sinfo)80 pthread_stackseg_np(pthread_t thread, stack_t *sinfo)
81 {
82 	if (thread->stack) {
83 #ifdef MACHINE_STACK_GROWS_UP
84 		sinfo->ss_sp = thread->stack->base;
85 #else
86 		sinfo->ss_sp = (char *)thread->stack->base +
87 		    thread->stack->len;
88 #endif
89 		sinfo->ss_size = thread->stack->len;
90 		if (thread->stack->guardsize != 1)
91 			sinfo->ss_size -= thread->stack->guardsize;
92 		sinfo->ss_flags = 0;
93 		return (0);
94 	} else if (thread->tib->tib_thread_flags & TIB_THREAD_INITIAL_STACK) {
95 		static struct _ps_strings _ps;
96 		static struct rlimit rl;
97 		static int gotself;
98 
99 		if (!_threads_ready)		/* for ROUND_TO_PAGE */
100 			_rthread_init();
101 
102 		if (gotself == 0) {
103 			const int mib[2] = { CTL_VM, VM_PSSTRINGS };
104 			size_t len;
105 
106 			if (getrlimit(RLIMIT_STACK, &rl) != 0)
107 				return (EAGAIN);
108 
109 			len = sizeof(_ps);
110 			if (sysctl(mib, 2, &_ps, &len, NULL, 0) != 0)
111 				return (EAGAIN);
112 			gotself = 1;
113 		}
114 
115 		/*
116 		 * Provides a rough estimation of stack bounds.   Caller
117 		 * likely wants to know for the purpose of inspecting call
118 		 * frames, but VM_PSSTRINGS points to process arguments...
119 		 */
120 #ifdef MACHINE_STACK_GROWS_UP
121 		sinfo->ss_sp = _ps.val;
122 #else
123 		sinfo->ss_sp = (void *)ROUND_TO_PAGE((uintptr_t)_ps.val);
124 #endif
125 		sinfo->ss_size = (size_t)rl.rlim_cur;
126 		sinfo->ss_flags = 0;
127 		return (0);
128 	}
129 	return (EAGAIN);
130 }
131