1 /*-
2 * Copyright (c) 2015 Ruslan Bukin <br@bsdpad.com>
3 * All rights reserved.
4 *
5 * Portions of this software were developed by SRI International and the
6 * University of Cambridge Computer Laboratory under DARPA/AFRL contract
7 * FA8750-10-C-0237 ("CTSRD"), as part of the DARPA CRASH research programme.
8 *
9 * Portions of this software were developed by the University of Cambridge
10 * Computer Laboratory as part of the CTSRD Project, with support from the
11 * UK Higher Education Innovation Fund (HEIF).
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35 #include <sys/param.h>
36
37 #include <machine/riscvreg.h>
38
39 #include <inttypes.h>
40 #include <stdarg.h>
41 #include <stdlib.h>
42 #include <ucontext.h>
43
44 void _ctx_start(void);
45
46 void
ctx_done(ucontext_t * ucp)47 ctx_done(ucontext_t *ucp)
48 {
49
50 if (ucp->uc_link == NULL) {
51 exit(0);
52 } else {
53 setcontext((const ucontext_t *)ucp->uc_link);
54 abort();
55 }
56 }
57
58 __weak_reference(__makecontext, makecontext);
59
60 void
__makecontext(ucontext_t * ucp,void (* func)(void),int argc,...)61 __makecontext(ucontext_t *ucp, void (*func)(void), int argc, ...)
62 {
63 struct gpregs *gp;
64 va_list ap;
65 int i;
66
67 /* A valid context is required. */
68 if (ucp == NULL)
69 return;
70
71 if ((argc < 0) || (argc > 8))
72 return;
73
74 gp = &ucp->uc_mcontext.mc_gpregs;
75
76 va_start(ap, argc);
77 /* Pass up to eight arguments in a0-7. */
78 for (i = 0; i < argc && i < 8; i++)
79 gp->gp_a[i] = va_arg(ap, uint64_t);
80 va_end(ap);
81
82 /* Set the stack */
83 gp->gp_sp = STACKALIGN(ucp->uc_stack.ss_sp + ucp->uc_stack.ss_size);
84 /* Arrange for return via the trampoline code. */
85 gp->gp_sepc = (__register_t)_ctx_start;
86 gp->gp_s[0] = (__register_t)func;
87 gp->gp_s[1] = (__register_t)ucp;
88 }
89