gdb/i386v-nat.c

   1 /* Intel 386 native support for SYSV systems (pre-SVR4).
   2    Copyright (C) 1988, 1989, 1991, 1992 Free Software Foundation, Inc.
   3
   4 This file is part of GDB.
   5
   6 This program is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2 of the License, or
   9 (at your option) any later version.
  10
  11 This program is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with this program; if not, write to the Free Software
  18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  19
  20 #include "defs.h"
  21 #include "frame.h"
  22 #include "inferior.h"
  23 #include "language.h"
  24 #include "gdbcore.h"
  25
  26 #ifdef USG
  27 #include <sys/types.h>
  28 #endif
  29
  30 #include <sys/param.h>
  31 #include <sys/dir.h>
  32 #include <signal.h>
  33 #include <sys/user.h>
  34 #include <sys/ioctl.h>
  35 #include <fcntl.h>
  36
  37 #include <sys/file.h>
  38 #include <sys/stat.h>
  39
  40 #ifndef NO_SYS_REG_H
  41 #include <sys/reg.h>
  42 #endif
  43
  44 #include "floatformat.h"
  45
  46 #include "target.h"
  47
  48 \f
  49 /* this table must line up with REGISTER_NAMES in tm-i386v.h */
  50 /* symbols like 'EAX' come from <sys/reg.h> */
  51 static int regmap[] =
  52 {
  53   EAX, ECX, EDX, EBX,
  54   UESP, EBP, ESI, EDI,
  55   EIP, EFL, CS, SS,
  56   DS, ES, FS, GS,
  57 };
  58
  59 /* blockend is the value of u.u_ar0, and points to the
  60  * place where GS is stored
  61  */
  62
  63 int
  64 i386_register_u_addr (blockend, regnum)
  65      int blockend;
  66      int regnum;
  67 {
  68 #if 0
  69   /* this will be needed if fp registers are reinstated */
  70   /* for now, you can look at them with 'info float'
  71    * sys5 wont let you change them with ptrace anyway
  72    */
  73   if (regnum >= FP0_REGNUM && regnum <= FP7_REGNUM)
  74     {
  75       int ubase, fpstate;
  76       struct user u;
  77       ubase = blockend + 4 * (SS + 1) - KSTKSZ;
  78       fpstate = ubase + ((char *)&u.u_fpstate - (char *)&u);
  79       return (fpstate + 0x1c + 10 * (regnum - FP0_REGNUM));
  80     }
  81   else
  82 #endif
  83     return (blockend + 4 * regmap[regnum]);
  84
  85 }
  86
  87 #if 0
  88 /* using FLOAT_INFO as is would be a problem.  FLOAT_INFO is called
  89    via a command xxx and eventually calls ptrace without ever having
  90    traversed the target vector.  This would be terribly impolite
  91    behaviour for a sun4 hosted remote gdb.
  92
  93    A fix might be to move this code into the "info registers" command.
  94    rich@cygnus.com 15 Sept 92. */
  95 i386_float_info ()
  96 {
  97   struct user u; /* just for address computations */
  98   int i;
  99   /* fpstate defined in <sys/user.h> */
 100   struct fpstate *fpstatep;
 101   char buf[sizeof (struct fpstate) + 2 * sizeof (int)];
 102   unsigned int uaddr;
 103   char fpvalid = 0;
 104   unsigned int rounded_addr;
 105   unsigned int rounded_size;
 106   extern int corechan;
 107   int skip;
 108
 109   uaddr = (char *)&u.u_fpvalid - (char *)&u;
 110   if (target_has_execution)
 111     {
 112       unsigned int data;
 113       unsigned int mask;
 114
 115       rounded_addr = uaddr & -sizeof (int);
 116       data = ptrace (3, inferior_pid, (PTRACE_ARG3_TYPE) rounded_addr, 0);
 117       mask = 0xff << ((uaddr - rounded_addr) * 8);
 118
 119       fpvalid = ((data & mask) != 0);
 120     }
 121 #if 0
 122   else
 123     {
 124       if (lseek (corechan, uaddr, 0) < 0)
 125         perror ("seek on core file");
 126       if (myread (corechan, &fpvalid, 1) < 0)
 127         perror ("read on core file");
 128
 129     }
 130 #endif  /* no core support yet */
 131
 132   if (fpvalid == 0)
 133     {
 134       printf_unfiltered ("no floating point status saved\n");
 135       return;
 136     }
 137
 138   uaddr = (char *)&U_FPSTATE(u) - (char *)&u;
 139   if (target_has_execution)
 140     {
 141       int *ip;
 142
 143       rounded_addr = uaddr & -sizeof (int);
 144       rounded_size = (((uaddr + sizeof (struct fpstate)) - uaddr) +
 145                       sizeof (int) - 1) / sizeof (int);
 146       skip = uaddr - rounded_addr;
 147
 148       ip = (int *)buf;
 149       for (i = 0; i < rounded_size; i++)
 150         {
 151           *ip++ = ptrace (3, inferior_pid, (PTRACE_ARG3_TYPE) rounded_addr, 0);
 152           rounded_addr += sizeof (int);
 153         }
 154     }
 155 #if 0
 156   else
 157     {
 158       if (lseek (corechan, uaddr, 0) < 0)
 159         perror_with_name ("seek on core file");
 160       if (myread (corechan, buf, sizeof (struct fpstate)) < 0)
 161         perror_with_name ("read from core file");
 162       skip = 0;
 163     }
 164 #endif  /* 0 */
 165
 166   fpstatep = (struct fpstate *)(buf + skip);
 167   print_387_status (fpstatep->status, (struct env387 *)fpstatep->state);
 168 }
 169
 170 #endif /* never */