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
  48   registers_fetched ();
  49
  50   ptrace (PTRACE_GETREGS, inferior_pid,
  51           (PTRACE_ARG3_TYPE) &inferior_registers);
  52   ptrace (PTRACE_GETFPREGS, inferior_pid,
  53           (PTRACE_ARG3_TYPE) &inferior_fp_registers);
  54
  55   memcpy (registers, &inferior_registers, sizeof inferior_registers);
  56
  57   memcpy (&registers[REGISTER_BYTE (FP0_REGNUM)],
  58          inferior_fp_registers.f_st,
  59          sizeof inferior_fp_registers.f_st);
  60   memcpy (&registers[REGISTER_BYTE (FPC_REGNUM)],
  61          &inferior_fp_registers.f_ctrl,
  62          sizeof inferior_fp_registers - sizeof inferior_fp_registers.f_st);
  63 }
  64
  65 /* Store our register values back into the inferior.
  66    If REGNO is -1, do this for all registers.
  67    Otherwise, REGNO specifies which register (so we can save time).  */
  68
  69 void
  70 store_inferior_registers (regno)
  71      int regno;
  72 {
  73   struct regs inferior_registers;
  74   struct fp_state inferior_fp_registers;
  75
  76   memcpy (&inferior_registers, registers, 20 * 4);
  77
  78   memcpy (inferior_fp_registers.f_st,&registers[REGISTER_BYTE (FP0_REGNUM)],
  79          sizeof inferior_fp_registers.f_st);
  80   memcpy (&inferior_fp_registers.f_ctrl,
  81          &registers[REGISTER_BYTE (FPC_REGNUM)],
  82          sizeof inferior_fp_registers - sizeof inferior_fp_registers.f_st);
  83
  84 #ifdef PTRACE_FP_BUG
  85   if (regno == FP_REGNUM || regno == -1)
  86     /* Storing the frame pointer requires a gross hack, in which an
  87        instruction that moves eax into ebp gets single-stepped.  */
  88     {
  89       int stack = inferior_registers.r_reg[SP_REGNUM];
  90       int stuff = ptrace (PTRACE_PEEKDATA, inferior_pid,
  91                           (PTRACE_ARG3_TYPE) stack);
  92       int reg = inferior_registers.r_reg[EAX];
  93       inferior_registers.r_reg[EAX] =
  94         inferior_registers.r_reg[FP_REGNUM];
  95       ptrace (PTRACE_SETREGS, inferior_pid,
  96               (PTRACE_ARG3_TYPE) &inferior_registers);
  97       ptrace (PTRACE_POKEDATA, inferior_pid, (PTRACE_ARG3_TYPE) stack, 0xc589);
  98       ptrace (PTRACE_SINGLESTEP, inferior_pid, (PTRACE_ARG3_TYPE) stack, 0);
  99       wait (0);
 100       ptrace (PTRACE_POKEDATA, inferior_pid, (PTRACE_ARG3_TYPE) stack, stuff);
 101       inferior_registers.r_reg[EAX] = reg;
 102     }
 103 #endif
 104   ptrace (PTRACE_SETREGS, inferior_pid,
 105           (PTRACE_ARG3_TYPE) &inferior_registers);
 106   ptrace (PTRACE_SETFPREGS, inferior_pid,
 107           (PTRACE_ARG3_TYPE) &inferior_fp_registers);
 108 }
 109
 110
 111
 112 /* Work with core files, for GDB. */
 113
 114 static void
 115 fetch_core_registers (core_reg_sect, core_reg_size, which, reg_addr)
 116      char *core_reg_sect;
 117      unsigned core_reg_size;
 118      int which;
 119      CORE_ADDR reg_addr;        /* Unused in this version */
 120 {
 121   int val;
 122
 123   switch (which) {
 124   case 0:
 125   case 1:
 126     memcpy (registers, core_reg_sect, core_reg_size);
 127     break;
 128
 129   case 2:
 130 #ifdef FP0_REGNUM
 131     memcpy (&registers[REGISTER_BYTE (FP0_REGNUM)],
 132            core_reg_sect,
 133            core_reg_size);              /* FIXME, probably bogus */
 134 #endif
 135 #ifdef FPC_REGNUM
 136     memcpy (&registers[REGISTER_BYTE (FPC_REGNUM)],
 137            &corestr.c_fpu.f_fpstatus.f_ctrl,
 138            sizeof corestr.c_fpu.f_fpstatus -
 139            sizeof corestr.c_fpu.f_fpstatus.f_st);
 140 #endif
 141     break;
 142   }
 143 }
 144
 145 \f
 146 /* Register that we are able to handle i386mach core file formats.
 147    FIXME: is this really bfd_target_unknown_flavour? */
 148
 149 static struct core_fns i386mach_core_fns =
 150 {
 151   bfd_target_unknown_flavour,
 152   fetch_core_registers,
 153   NULL
 154 };
 155
 156 void
 157 _initialize_core_i386mach ()
 158 {
 159   add_core_fns (&i386mach_core_fns);
 160 }