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/cdefs.h> 36 #include <sys/param.h> 37 38 #include <machine/riscvreg.h> 39 40 #include <inttypes.h> 41 #include <stdarg.h> 42 #include <stdlib.h> 43 #include <ucontext.h> 44 45 void _ctx_start(void); 46 47 void 48 ctx_done(ucontext_t *ucp) 49 { 50 51 if (ucp->uc_link == NULL) { 52 exit(0); 53 } else { 54 setcontext((const ucontext_t *)ucp->uc_link); 55 abort(); 56 } 57 } 58 59 __weak_reference(__makecontext, makecontext); 60 61 void 62 __makecontext(ucontext_t *ucp, void (*func)(void), int argc, ...) 63 { 64 struct gpregs *gp; 65 va_list ap; 66 int i; 67 68 /* A valid context is required. */ 69 if (ucp == NULL) 70 return; 71 72 if ((argc < 0) || (argc > 8)) 73 return; 74 75 gp = &ucp->uc_mcontext.mc_gpregs; 76 77 va_start(ap, argc); 78 /* Pass up to eight arguments in a0-7. */ 79 for (i = 0; i < argc && i < 8; i++) 80 gp->gp_a[i] = va_arg(ap, uint64_t); 81 va_end(ap); 82 83 /* Set the stack */ 84 gp->gp_sp = STACKALIGN(ucp->uc_stack.ss_sp + ucp->uc_stack.ss_size); 85 /* Arrange for return via the trampoline code. */ 86 gp->gp_sepc = (__register_t)_ctx_start; 87 gp->gp_s[0] = (__register_t)func; 88 gp->gp_s[1] = (__register_t)ucp; 89 } 90