lib/libc/arch/m68k/gen/longjmp.c

   1 /*      $NetBSD: longjmp.c,v 1.2 2008/04/28 20:22:56 martin Exp $       */
   2
   3 /*-
   4  * Copyright (c) 2003 The NetBSD Foundation, Inc.
   5  * All rights reserved.
   6  *
   7  * This code is derived from software contributed to The NetBSD Foundation
   8  * by Christian Limpach.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  29  * POSSIBILITY OF SUCH DAMAGE.
  30  */
  31
  32 #include "namespace.h"
  33 #include <sys/types.h>
  34 #include <ucontext.h>
  35 #include <signal.h>
  36 #include <stdlib.h>
  37 #include <string.h>
  38
  39 #define __LIBC12_SOURCE__
  40 #include <setjmp.h>
  41 #include <compat/include/setjmp.h>
  42
  43 typedef struct {
  44         __greg_t        __data[6];
  45         __greg_t        __addr[4];
  46 } __jmp_buf_regs_t;
  47
  48 void
  49 __longjmp14(jmp_buf env, int val)
  50 {
  51         struct sigcontext *sc = (void *)env;
  52         __jmp_buf_regs_t *r = (void *)&sc[1];
  53         ucontext_t uc;
  54
  55         /* Ensure non-zero SP */
  56         if (sc->sc_sp == 0)
  57                 goto err;
  58
  59         /* Make return value non-zero */
  60         if (val == 0)
  61                 val = 1;
  62
  63         /* Save return value in context */
  64         uc.uc_mcontext.__gregs[_REG_D0] = val;
  65
  66         /*
  67          * Set _UC_SIGMASK, _UC_CPU and _UC_M68K_UC_USER
  68          * Set _UC_{SET,CLR}STACK according to SS_ONSTACK
  69          */
  70         uc.uc_flags = _UC_SIGMASK | _UC_CPU | _UC_M68K_UC_USER |
  71                 (sc->sc_onstack ? _UC_SETSTACK : _UC_CLRSTACK);
  72
  73         /* Clear uc_link */
  74         uc.uc_link = 0;
  75
  76         /* Copy signal mask */
  77         uc.uc_sigmask = sc->sc_mask;
  78
  79         /* Copy SP/PC/PS/FP */
  80         uc.uc_mcontext.__gregs[_REG_A7] = sc->sc_sp;
  81         uc.uc_mcontext.__gregs[_REG_PC] = sc->sc_pc;
  82         uc.uc_mcontext.__gregs[_REG_PS] = sc->sc_ps;
  83         uc.uc_mcontext.__gregs[_REG_A6] = sc->sc_fp;
  84
  85         /* Copy remaining non-scratch regs. */
  86         memcpy(&uc.uc_mcontext.__gregs[_REG_D2],
  87             &r->__data, sizeof(r->__data));
  88         memcpy(&uc.uc_mcontext.__gregs[_REG_A2],
  89             &r->__addr, sizeof(r->__addr));
  90
  91         setcontext(&uc);
  92  err:
  93         longjmperror();
  94         abort();
  95         /* NOTREACHED */
  96 }