gdb/i386mach-nat.c

   1 /* Native dependent code for Mach 386's for GDB, the GNU debugger.
   2    Copyright (C) 1986, 1987, 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  19
  20 #include "defs.h"
  21 #include "frame.h"
  22 #include "inferior.h"
  23 #include "gdbcore.h"
  24
  25 #include <sys/param.h>
  26 #include <sys/dir.h>
  27 #include <sys/user.h>
  28 #include <signal.h>
  29 #include <sys/ioctl.h>
  30 #include <fcntl.h>
  31
  32 #include <sys/ptrace.h>
  33 #include <machine/reg.h>
  34
  35 #include <sys/file.h>
  36 #include "gdb_stat.h"
  37 #include <sys/core.h>
  38
  39 static void fetch_core_registers PARAMS ((char *, unsigned, int, CORE_ADDR));
  40
  41 void
  42 fetch_inferior_registers (regno)
  43      int regno;         /* Original value discarded */
  44 {
  45   struct regs inferior_registers;
  46   struct fp_state inferior_fp_registers;
  47   extern char registers[];
  48
  49   registers_fetched ();
  50
  51   ptrace (PTRACE_GETREGS, inferior_pid,
  52           (PTRACE_ARG3_TYPE) &inferior_registers);
  53   ptrace (PTRACE_GETFPREGS, inferior_pid,
  54           (PTRACE_ARG3_TYPE) &inferior_fp_registers);
  55
  56   memcpy (registers, &inferior_registers, sizeof inferior_registers);
  57
  58   memcpy (&registers[REGISTER_BYTE (FP0_REGNUM)],
  59          inferior_fp_registers.f_st,
  60          sizeof inferior_fp_registers.f_st);
  61   memcpy (&registers[REGISTER_BYTE (FPC_REGNUM)],
  62          &inferior_fp_registers.f_ctrl,
  63          sizeof inferior_fp_registers - sizeof inferior_fp_registers.f_st);
  64 }
  65
  66 /* Store our register values back into the inferior.
  67    If REGNO is -1, do this for all registers.
  68    Otherwise, REGNO specifies which register (so we can save time).  */
  69
  70 void
  71 store_inferior_registers (regno)
  72      int regno;
  73 {
  74   struct regs inferior_registers;
  75   struct fp_state inferior_fp_registers;
  76   extern char registers[];
  77
  78   memcpy (&inferior_registers, registers, 20 * 4);
  79
  80   memcpy (inferior_fp_registers.f_st,&registers[REGISTER_BYTE (FP0_REGNUM)],
  81          sizeof inferior_fp_registers.f_st);
  82   memcpy (&inferior_fp_registers.f_ctrl,
  83          &registers[REGISTER_BYTE (FPC_REGNUM)],
  84          sizeof inferior_fp_registers - sizeof inferior_fp_registers.f_st);
  85
  86 #ifdef PTRACE_FP_BUG
  87   if (regno == FP_REGNUM || regno == -1)
  88     /* Storing the frame pointer requires a gross hack, in which an
  89        instruction that moves eax into ebp gets single-stepped.  */
  90     {
  91       int stack = inferior_registers.r_reg[SP_REGNUM];
  92       int stuff = ptrace (PTRACE_PEEKDATA, inferior_pid,
  93                           (PTRACE_ARG3_TYPE) stack);
  94       int reg = inferior_registers.r_reg[EAX];
  95       inferior_registers.r_reg[EAX] =
  96         inferior_registers.r_reg[FP_REGNUM];
  97       ptrace (PTRACE_SETREGS, inferior_pid,
  98               (PTRACE_ARG3_TYPE) &inferior_registers);
  99       ptrace (PTRACE_POKEDATA, inferior_pid, (PTRACE_ARG3_TYPE) stack, 0xc589);
 100       ptrace (PTRACE_SINGLESTEP, inferior_pid, (PTRACE_ARG3_TYPE) stack, 0);
 101       wait (0);
 102       ptrace (PTRACE_POKEDATA, inferior_pid, (PTRACE_ARG3_TYPE) stack, stuff);
 103       inferior_registers.r_reg[EAX] = reg;
 104     }
 105 #endif
 106   ptrace (PTRACE_SETREGS, inferior_pid,
 107           (PTRACE_ARG3_TYPE) &inferior_registers);
 108   ptrace (PTRACE_SETFPREGS, inferior_pid,
 109           (PTRACE_ARG3_TYPE) &inferior_fp_registers);
 110 }
 111
 112
 113
 114 /* Work with core files, for GDB. */
 115
 116 static void
 117 fetch_core_registers (core_reg_sect, core_reg_size, which, reg_addr)
 118      char *core_reg_sect;
 119      unsigned core_reg_size;
 120      int which;
 121      CORE_ADDR reg_addr;        /* Unused in this version */
 122 {
 123   int val;
 124   extern char registers[];
 125
 126   switch (which) {
 127   case 0:
 128   case 1:
 129     memcpy (registers, core_reg_sect, core_reg_size);
 130     break;
 131
 132   case 2:
 133 #ifdef FP0_REGNUM
 134     memcpy (&registers[REGISTER_BYTE (FP0_REGNUM)],
 135            core_reg_sect,
 136            core_reg_size);              /* FIXME, probably bogus */
 137 #endif
 138 #ifdef FPC_REGNUM
 139     memcpy (&registers[REGISTER_BYTE (FPC_REGNUM)],
 140            &corestr.c_fpu.f_fpstatus.f_ctrl,
 141            sizeof corestr.c_fpu.f_fpstatus -
 142            sizeof corestr.c_fpu.f_fpstatus.f_st);
 143 #endif
 144     break;
 145   }
 146 }
 147
 148 \f
 149 /* Register that we are able to handle i386mach core file formats.
 150    FIXME: is this really bfd_target_unknown_flavour? */
 151
 152 static struct core_fns i386mach_core_fns =
 153 {
 154   bfd_target_unknown_flavour,
 155   fetch_core_registers,
 156   NULL
 157 };
 158
 159 void
 160 _initialize_core_i386mach ()
 161 {
 162   add_core_fns (&i386mach_core_fns);
 163 }