diff --git a/arch/m68k/makecontext.c b/arch/m68k/makecontext.c new file mode 100644 index 0000000..39cae2c --- /dev/null +++ b/arch/m68k/makecontext.c @@ -0,0 +1,55 @@ +/* + * Copyright (c) 2020 Ariadne Conill + * + * Permission to use, copy, modify, and/or distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * This software is provided 'as is' and without any warranty, express or + * implied. In no event shall the authors be liable for any damages arising + * from the use of this software. + */ + +#define _GNU_SOURCE +#include +#include +#include +#include +#include +#include +#include "defs.h" + + +extern void __start_context(void); + + +void +__makecontext(ucontext_t *ucp, void (*func)(void), int argc, ...) +{ + greg_t *sp; + va_list va; + int i; + + /* set up and align the stack. */ + sp = (greg_t *) ((uintptr_t) ucp->uc_stack.ss_sp + ucp->uc_stack.ss_size); + sp -= (argc + 1); + sp = (greg_t *) (((uintptr_t) sp & ~0x3)); + + /* set up the ucontext structure */ + ucp->uc_mcontext.gregs[REG_SP] = (greg_t) sp; + ucp->uc_mcontext.gregs[REG_A6] = 0; + + /* return address */ + *sp++ = (greg_t) __start_context; + + va_start(va, argc); + + /* all arguments overflow into stack */ + for (i = 0; i < argc; i++) + *sp++ = va_arg (va, greg_t); + + va_end(va); +} + + +extern __typeof(__makecontext) makecontext __attribute__((weak, __alias__("__makecontext")));