1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2004 Olivier Houchard
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #include <sys/param.h>
30 #include <sys/signal.h>
31 #include <sys/ucontext.h>
32
33 #include <machine/frame.h>
34 #include <machine/sigframe.h>
35
36 #include <errno.h>
37 #include <stdarg.h>
38 #include <stdlib.h>
39 #include <unistd.h>
40 #include <strings.h>
41 #include <signal.h>
42
43 __weak_reference(__signalcontext, signalcontext);
44
45 extern void _ctx_start(void);
46
47 int
__signalcontext(ucontext_t * ucp,int sig,__sighandler_t * func)48 __signalcontext(ucontext_t *ucp, int sig, __sighandler_t *func)
49 {
50 struct sigframe *sfp;
51 __greg_t *gr = ucp->uc_mcontext.__gregs;
52 unsigned int *sp;
53
54 sp = (unsigned int *)gr[_REG_SP];
55
56 sfp = (struct sigframe *)sp - 1;
57
58 bzero(sfp, sizeof(*sfp));
59 bcopy(ucp, &sfp->sf_uc, sizeof(*ucp));
60 sfp->sf_si.si_signo = sig;
61
62 gr[_REG_SP] = (__greg_t)sfp;
63 /* Wipe out frame pointer. */
64 gr[_REG_FP] = 0;
65 /* Arrange for return via the trampoline code. */
66 gr[_REG_PC] = (__greg_t)_ctx_start;
67 gr[_REG_R4] = (__greg_t)func;
68 gr[_REG_R5] = (__greg_t)ucp;
69 gr[_REG_R0] = (__greg_t)sig;
70 gr[_REG_R1] = (__greg_t)&sfp->sf_si;
71 gr[_REG_R2] = (__greg_t)&sfp->sf_uc;
72
73 ucp->uc_link = &sfp->sf_uc;
74 sigdelset(&ucp->uc_sigmask, sig);
75
76 return (0);
77 }
78