xref: /illumos-gate/usr/src/lib/libc/sparc/gen/siglongjmp.c (revision 7c478bd95313f5f23a4c958a745db2134aa0324)
1*7c478bd9Sstevel@tonic-gate /*
2*7c478bd9Sstevel@tonic-gate  * CDDL HEADER START
3*7c478bd9Sstevel@tonic-gate  *
4*7c478bd9Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*7c478bd9Sstevel@tonic-gate  * Common Development and Distribution License, Version 1.0 only
6*7c478bd9Sstevel@tonic-gate  * (the "License").  You may not use this file except in compliance
7*7c478bd9Sstevel@tonic-gate  * with the License.
8*7c478bd9Sstevel@tonic-gate  *
9*7c478bd9Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*7c478bd9Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
11*7c478bd9Sstevel@tonic-gate  * See the License for the specific language governing permissions
12*7c478bd9Sstevel@tonic-gate  * and limitations under the License.
13*7c478bd9Sstevel@tonic-gate  *
14*7c478bd9Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
15*7c478bd9Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*7c478bd9Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
17*7c478bd9Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
18*7c478bd9Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
19*7c478bd9Sstevel@tonic-gate  *
20*7c478bd9Sstevel@tonic-gate  * CDDL HEADER END
21*7c478bd9Sstevel@tonic-gate  */
22*7c478bd9Sstevel@tonic-gate /*
23*7c478bd9Sstevel@tonic-gate  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
24*7c478bd9Sstevel@tonic-gate  * Use is subject to license terms.
25*7c478bd9Sstevel@tonic-gate  */
26*7c478bd9Sstevel@tonic-gate 
27*7c478bd9Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"
28*7c478bd9Sstevel@tonic-gate 
29*7c478bd9Sstevel@tonic-gate /*	Copyright (c) 1988 AT&T	*/
30*7c478bd9Sstevel@tonic-gate /*	  All Rights Reserved  	*/
31*7c478bd9Sstevel@tonic-gate 
32*7c478bd9Sstevel@tonic-gate 
33*7c478bd9Sstevel@tonic-gate #pragma weak siglongjmp = _siglongjmp
34*7c478bd9Sstevel@tonic-gate 
35*7c478bd9Sstevel@tonic-gate #include "lint.h"
36*7c478bd9Sstevel@tonic-gate #include <sys/types.h>
37*7c478bd9Sstevel@tonic-gate #include <sys/stack.h>
38*7c478bd9Sstevel@tonic-gate #include <sys/frame.h>
39*7c478bd9Sstevel@tonic-gate #include <memory.h>
40*7c478bd9Sstevel@tonic-gate #include <ucontext.h>
41*7c478bd9Sstevel@tonic-gate #include <setjmp.h>
42*7c478bd9Sstevel@tonic-gate #include "sigjmp_struct.h"
43*7c478bd9Sstevel@tonic-gate #include "libc.h"
44*7c478bd9Sstevel@tonic-gate 
45*7c478bd9Sstevel@tonic-gate void
46*7c478bd9Sstevel@tonic-gate _siglongjmp(sigjmp_buf env, int val)
47*7c478bd9Sstevel@tonic-gate {
48*7c478bd9Sstevel@tonic-gate 	extern void _fetch_globals(greg_t *);
49*7c478bd9Sstevel@tonic-gate 	ucontext_t uc;
50*7c478bd9Sstevel@tonic-gate 	greg_t *reg = uc.uc_mcontext.gregs;
51*7c478bd9Sstevel@tonic-gate 	volatile sigjmp_struct_t *bp = (sigjmp_struct_t *)env;
52*7c478bd9Sstevel@tonic-gate 	greg_t fp = bp->sjs_fp;
53*7c478bd9Sstevel@tonic-gate 	greg_t i7 = bp->sjs_i7;
54*7c478bd9Sstevel@tonic-gate 
55*7c478bd9Sstevel@tonic-gate 	/*
56*7c478bd9Sstevel@tonic-gate 	 * Create a ucontext_t structure from scratch.
57*7c478bd9Sstevel@tonic-gate 	 * We only need to fetch the globals.
58*7c478bd9Sstevel@tonic-gate 	 * The outs are assumed to be trashed on return from sigsetjmp().
59*7c478bd9Sstevel@tonic-gate 	 * The ins and locals are restored from the resumed register window.
60*7c478bd9Sstevel@tonic-gate 	 * The floating point state is unmodified.
61*7c478bd9Sstevel@tonic-gate 	 * Everything else is in the sigjmp_struct_t buffer.
62*7c478bd9Sstevel@tonic-gate 	 */
63*7c478bd9Sstevel@tonic-gate 	(void) memset(&uc, 0, sizeof (uc));
64*7c478bd9Sstevel@tonic-gate 	uc.uc_flags = UC_STACK | UC_CPU;
65*7c478bd9Sstevel@tonic-gate 	_fetch_globals(&reg[REG_G1]);
66*7c478bd9Sstevel@tonic-gate 	uc.uc_stack = bp->sjs_stack;
67*7c478bd9Sstevel@tonic-gate 	uc.uc_link = bp->sjs_uclink;
68*7c478bd9Sstevel@tonic-gate 	reg[REG_PC] = bp->sjs_pc;
69*7c478bd9Sstevel@tonic-gate 	reg[REG_nPC] = reg[REG_PC] + 0x4;
70*7c478bd9Sstevel@tonic-gate 	reg[REG_SP] = bp->sjs_sp;
71*7c478bd9Sstevel@tonic-gate 
72*7c478bd9Sstevel@tonic-gate 	if (bp->sjs_flags & JB_SAVEMASK) {
73*7c478bd9Sstevel@tonic-gate 		uc.uc_flags |= UC_SIGMASK;
74*7c478bd9Sstevel@tonic-gate 		uc.uc_sigmask = bp->sjs_sigmask;
75*7c478bd9Sstevel@tonic-gate 	}
76*7c478bd9Sstevel@tonic-gate 
77*7c478bd9Sstevel@tonic-gate 	if (val)
78*7c478bd9Sstevel@tonic-gate 		reg[REG_O0] = (greg_t)val;
79*7c478bd9Sstevel@tonic-gate 	else
80*7c478bd9Sstevel@tonic-gate 		reg[REG_O0] = (greg_t)1;
81*7c478bd9Sstevel@tonic-gate 
82*7c478bd9Sstevel@tonic-gate 	/*
83*7c478bd9Sstevel@tonic-gate 	 * Copy the fp and i7 values into the register window save area.
84*7c478bd9Sstevel@tonic-gate 	 * These may have been clobbered between calls to sigsetjmp
85*7c478bd9Sstevel@tonic-gate 	 * and siglongjmp.  For example, the save area could have been
86*7c478bd9Sstevel@tonic-gate 	 * relocated to lower addresses and the original save area
87*7c478bd9Sstevel@tonic-gate 	 * given to an alloca() call.  Notice that all reads from
88*7c478bd9Sstevel@tonic-gate 	 * the sigjmp_struct_t buffer should take place before the
89*7c478bd9Sstevel@tonic-gate 	 * following two writes.  It is possible that user code may
90*7c478bd9Sstevel@tonic-gate 	 * move/copy the sigjmpbuf around, and overlap the original
91*7c478bd9Sstevel@tonic-gate 	 * register window save area.
92*7c478bd9Sstevel@tonic-gate 	 */
93*7c478bd9Sstevel@tonic-gate 	if (bp->sjs_sp != 0 && (bp->sjs_flags & JB_FRAMEPTR)) {
94*7c478bd9Sstevel@tonic-gate 		struct frame *sp = (struct frame *)(bp->sjs_sp + STACK_BIAS);
95*7c478bd9Sstevel@tonic-gate 		sp->fr_savfp = (struct frame *)fp;
96*7c478bd9Sstevel@tonic-gate 		sp->fr_savpc = i7;
97*7c478bd9Sstevel@tonic-gate 	}
98*7c478bd9Sstevel@tonic-gate 
99*7c478bd9Sstevel@tonic-gate 	(void) setcontext(&uc);
100*7c478bd9Sstevel@tonic-gate }
101