common/lib/libx86emu/x86emu_util.c

   1 /*      $NetBSD: x86emu_util.c,v 1.1 2007/11/30 20:02:50 joerg Exp $    */
   2
   3 /****************************************************************************
   4 *
   5 *  Realmode X86 Emulator Library
   6 *
   7 *  Copyright (C) 1996-1999 SciTech Software, Inc.
   8 *  Copyright (C) David Mosberger-Tang
   9 *  Copyright (C) 1999 Egbert Eich
  10 *  Copyright (C) 2007 Joerg Sonnenberger
  11 *
  12 *  ========================================================================
  13 *
  14 *  Permission to use, copy, modify, distribute, and sell this software and
  15 *  its documentation for any purpose is hereby granted without fee,
  16 *  provided that the above copyright notice appear in all copies and that
  17 *  both that copyright notice and this permission notice appear in
  18 *  supporting documentation, and that the name of the authors not be used
  19 *  in advertising or publicity pertaining to distribution of the software
  20 *  without specific, written prior permission.  The authors makes no
  21 *  representations about the suitability of this software for any purpose.
  22 *  It is provided "as is" without express or implied warranty.
  23 *
  24 *  THE AUTHORS DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
  25 *  INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
  26 *  EVENT SHALL THE AUTHORS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
  27 *  CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF
  28 *  USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
  29 *  OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  30 *  PERFORMANCE OF THIS SOFTWARE.
  31 *
  32 ****************************************************************************/
  33
  34 #include <x86emu/x86emu.h>
  35 #include <x86emu/x86emu_regs.h>
  36
  37 #include <sys/endian.h>
  38 #include <sys/null.h>
  39
  40 /****************************************************************************
  41 PARAMETERS:
  42 addr    - Emulator memory address to read
  43
  44 RETURNS:
  45 Byte value read from emulator memory.
  46
  47 REMARKS:
  48 Reads a byte value from the emulator memory.
  49 ****************************************************************************/
  50 static uint8_t
  51 rdb(struct X86EMU *emu, uint32_t addr)
  52 {
  53         if (addr > emu->mem_size - 1)
  54                 X86EMU_halt_sys(emu);
  55         return emu->mem_base[addr];
  56 }
  57 /****************************************************************************
  58 PARAMETERS:
  59 addr    - Emulator memory address to read
  60
  61 RETURNS:
  62 Word value read from emulator memory.
  63
  64 REMARKS:
  65 Reads a word value from the emulator memory.
  66 ****************************************************************************/
  67 static uint16_t
  68 rdw(struct X86EMU *emu, uint32_t addr)
  69 {
  70         if (addr > emu->mem_size - 2)
  71                 X86EMU_halt_sys(emu);
  72         return le16dec(emu->mem_base + addr);
  73 }
  74 /****************************************************************************
  75 PARAMETERS:
  76 addr    - Emulator memory address to read
  77
  78 RETURNS:
  79 Long value read from emulator memory.
  80 REMARKS:
  81 Reads a long value from the emulator memory.
  82 ****************************************************************************/
  83 static uint32_t
  84 rdl(struct X86EMU *emu, uint32_t addr)
  85 {
  86         if (addr > emu->mem_size - 4)
  87                 X86EMU_halt_sys(emu);
  88         return le32dec(emu->mem_base + addr);
  89 }
  90 /****************************************************************************
  91 PARAMETERS:
  92 addr    - Emulator memory address to read
  93 val             - Value to store
  94
  95 REMARKS:
  96 Writes a byte value to emulator memory.
  97 ****************************************************************************/
  98 static void
  99 wrb(struct X86EMU *emu, uint32_t addr, uint8_t val)
 100 {
 101         if (addr > emu->mem_size - 1)
 102                 X86EMU_halt_sys(emu);
 103         emu->mem_base[addr] = val;
 104 }
 105 /****************************************************************************
 106 PARAMETERS:
 107 addr    - Emulator memory address to read
 108 val             - Value to store
 109
 110 REMARKS:
 111 Writes a word value to emulator memory.
 112 ****************************************************************************/
 113 static void
 114 wrw(struct X86EMU *emu, uint32_t addr, uint16_t val)
 115 {
 116         if (addr > emu->mem_size - 2)
 117                 X86EMU_halt_sys(emu);
 118         le16enc(emu->mem_base + addr, val);
 119 }
 120 /****************************************************************************
 121 PARAMETERS:
 122 addr    - Emulator memory address to read
 123 val             - Value to store
 124
 125 REMARKS:
 126 Writes a long value to emulator memory.
 127 ****************************************************************************/
 128 static void
 129 wrl(struct X86EMU *emu, uint32_t addr, uint32_t val)
 130 {
 131         if (addr > emu->mem_size - 4)
 132                 X86EMU_halt_sys(emu);
 133         le32enc(emu->mem_base + addr, val);
 134 }
 135
 136 /*----------------------------- Setup -------------------------------------*/
 137
 138 void
 139 X86EMU_init_default(struct X86EMU *emu)
 140 {
 141         int i;
 142
 143         emu->emu_rdb = rdb;
 144         emu->emu_rdw = rdw;
 145         emu->emu_rdl = rdl;
 146         emu->emu_wrb = wrb;
 147         emu->emu_wrw = wrw;
 148         emu->emu_wrl = wrl;
 149
 150         for (i = 0; i < 256; i++)
 151                 emu->_X86EMU_intrTab[i] = NULL;
 152 }