lib/libc/arch/sparc64/gen/_lwp.c

   1 /*      $NetBSD: _lwp.c,v 1.7 2012/03/17 20:48:58 martin Exp $  */
   2
   3 /*-
   4  * Copyright (c) 2002 The NetBSD Foundation, Inc.
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  17  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  18  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  26  * POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 #include <sys/cdefs.h>
  30 #if defined(LIBC_SCCS) && !defined(lint)
  31 __RCSID("$NetBSD: _lwp.c,v 1.7 2012/03/17 20:48:58 martin Exp $");
  32 #endif /* LIBC_SCCS and not lint */
  33
  34 #include "namespace.h"
  35 #include <sys/types.h>
  36 #include <ucontext.h>
  37 #include <lwp.h>
  38 #include <stdlib.h>
  39
  40 void
  41 _lwp_makecontext(ucontext_t *u, void (*start)(void *),
  42                       void *arg, void *private,
  43                       caddr_t stack_base, size_t stack_size)
  44 {
  45         __greg_t *gr;
  46         unsigned long *sp;
  47
  48         getcontext(u);
  49         gr = u->uc_mcontext.__gregs;
  50
  51         u->uc_link = NULL;
  52
  53         u->uc_stack.ss_sp = stack_base;
  54         u->uc_stack.ss_size = stack_size;
  55
  56         /*LINTED*/
  57         sp = (ulong *)(stack_base + stack_size);
  58         sp = (ulong *)((ulong)sp & ~0x0f);
  59
  60         sp -= 8 + 8 + 6;
  61
  62         sp[8]  = (ulong)arg;
  63         sp[14] = (ulong)sp - 2047;
  64         sp[15] = (ulong)_lwp_exit - 8;
  65
  66         /*LINTED*/
  67         sp = (ulong *)((caddr_t)sp - 2047);
  68
  69         gr[_REG_PC] = (ulong) start;
  70         gr[_REG_nPC] = (ulong) start + 4;
  71
  72         gr[_REG_O0] = (ulong) arg;
  73         gr[_REG_O6] = (ulong) sp;
  74         gr[_REG_O7] = (ulong)_lwp_exit - 8;
  75         gr[_REG_G7] = (ulong)private;
  76 }