2 * Copyright (c) 2004 Olivier Houchard
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
30 #include <sys/param.h>
31 #include <sys/signal.h>
32 #include <sys/ucontext.h>
34 #include <machine/frame.h>
35 #include <machine/sigframe.h>
44 __weak_reference(__signalcontext, signalcontext);
46 extern void _ctx_start(void);
49 __signalcontext(ucontext_t *ucp, int sig, __sighandler_t *func)
52 __greg_t *gr = ucp->uc_mcontext.__gregs;
55 sp = (unsigned int *)gr[_REG_SP];
57 sfp = (struct sigframe *)sp - 1;
59 bzero(sfp, sizeof(*sfp));
60 bcopy(ucp, &sfp->sf_uc, sizeof(*ucp));
61 sfp->sf_si.si_signo = sig;
63 gr[_REG_SP] = (__greg_t)sfp;
64 /* Wipe out frame pointer. */
66 /* Arrange for return via the trampoline code. */
67 gr[_REG_PC] = (__greg_t)_ctx_start;
68 gr[_REG_R4] = (__greg_t)func;
69 gr[_REG_R5] = (__greg_t)ucp;
70 gr[_REG_R0] = (__greg_t)sig;
71 gr[_REG_R1] = (__greg_t)&sfp->sf_si;
72 gr[_REG_R2] = (__greg_t)&sfp->sf_uc;
74 ucp->uc_link = &sfp->sf_uc;
75 sigdelset(&ucp->uc_sigmask, sig);