diff options
Diffstat (limited to 'lib/libc/mips/gen/makecontext.c')
| -rw-r--r-- | lib/libc/mips/gen/makecontext.c | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/lib/libc/mips/gen/makecontext.c b/lib/libc/mips/gen/makecontext.c new file mode 100644 index 0000000..f2a826e --- /dev/null +++ b/lib/libc/mips/gen/makecontext.c @@ -0,0 +1,123 @@ +/* $NetBSD: makecontext.c,v 1.5 2009/12/14 01:07:42 matt Exp $ */ + +/*- + * Copyright (c) 2001 The NetBSD Foundation, Inc. + * All rights reserved. + * + * This code is derived from software contributed to The NetBSD Foundation + * by Klaus Klein. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS + * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED + * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR + * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS + * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); +#if defined(LIBC_SCCS) && !defined(lint) +__RCSID("$NetBSD: makecontext.c,v 1.5 2009/12/14 01:07:42 matt Exp $"); +#endif + +#include <sys/param.h> +#include <machine/regnum.h> + +#include <stdarg.h> +#include <stdlib.h> +#include <unistd.h> +#include <stdio.h> +#include <ucontext.h> + +__weak_reference(__makecontext, makecontext); + +void _ctx_done(ucontext_t *); +void _ctx_start(void); + +void +__makecontext(ucontext_t *ucp, void (*func)(void), int argc, ...) +{ + mcontext_t *mc; + register_t *sp; + int i; + va_list ap; + + /* + * XXX/juli + * We need an mc_len or mc_flags like other architectures + * so that we can mark a context as invalid. Store it in + * mc->mc_regs[ZERO] perhaps? + */ + if (argc < 0 || argc > 6 || ucp == NULL || + ucp->uc_stack.ss_sp == NULL || + ucp->uc_stack.ss_size < MINSIGSTKSZ) + return; + mc = &ucp->uc_mcontext; + + sp = (register_t *) + ((uintptr_t)ucp->uc_stack.ss_sp + ucp->uc_stack.ss_size); +#if defined(__mips_o32) || defined(__mips_o64) + sp -= (argc >= 4 ? argc : 4); /* Make room for >=4 arguments. */ + sp = (register_t *) + ((uintptr_t)sp & ~0x7); /* Align on double-word boundary. */ +#elif defined(__mips_n32) || defined(__mips_n64) + sp -= (argc > 8 ? argc - 8 : 0); /* Make room for > 8 arguments. */ + sp = (register_t *) + ((uintptr_t)sp & ~0xf); /* Align on quad-word boundary. */ +#endif + + mc->mc_regs[SP] = (intptr_t)sp; + mc->mc_regs[S0] = (intptr_t)ucp; + mc->mc_regs[T9] = (intptr_t)func; + mc->mc_pc = (intptr_t)_ctx_start; + + /* Construct argument list. */ + va_start(ap, argc); +#if defined(__mips_o32) || defined(__mips_o64) + /* Up to the first four arguments are passed in $a0-3. */ + for (i = 0; i < argc && i < 4; i++) + /* LINTED register_t is safe */ + mc->mc_regs[A0 + i] = va_arg(ap, register_t); + /* Pass remaining arguments on the stack above the $a0-3 gap. */ + sp += i; +#endif +#if defined(__mips_n32) || defined(__mips_n64) + /* Up to the first 8 arguments are passed in $a0-7. */ + for (i = 0; i < argc && i < 8; i++) + /* LINTED register_t is safe */ + mc->mc_regs[A0 + i] = va_arg(ap, register_t); + /* Pass remaining arguments on the stack above the $a0-3 gap. */ +#endif + /* Pass remaining arguments on the stack above the $a0-3 gap. */ + for (; i < argc; i++) + /* LINTED uintptr_t is safe */ + *sp++ = va_arg(ap, register_t); + va_end(ap); +} + +void +_ctx_done(ucontext_t *ucp) +{ + + if (ucp->uc_link == NULL) + exit(0); + else { + setcontext((const ucontext_t *)ucp->uc_link); + abort(); + } +} |
