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., 675 Mass Ave, Cambridge, MA 02139, 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 <sys/stat.h>
  37 #include <sys/core.h>
  38
  39
  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   bcopy (&inferior_registers, registers, sizeof inferior_registers);
  57
  58   bcopy (inferior_fp_registers.f_st,&registers[REGISTER_BYTE (FP0_REGNUM)],
  59          sizeof inferior_fp_registers.f_st);
  60   bcopy (&inferior_fp_registers.f_ctrl,
  61          &registers[REGISTER_BYTE (FPC_REGNUM)],
  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   extern char registers[];
  76
  77   bcopy (registers, &inferior_registers, 20 * 4);
  78
  79   bcopy (&registers[REGISTER_BYTE (FP0_REGNUM)],inferior_fp_registers.f_st,
  80          sizeof inferior_fp_registers.f_st);
  81   bcopy (&registers[REGISTER_BYTE (FPC_REGNUM)],
  82          &inferior_fp_registers.f_ctrl,
  83          sizeof inferior_fp_registers - sizeof inferior_fp_registers.f_st);
  84
  85 #ifdef PTRACE_FP_BUG
  86   if (regno == FP_REGNUM || regno == -1)
  87     /* Storing the frame pointer requires a gross hack, in which an
  88        instruction that moves eax into ebp gets single-stepped.  */
  89     {
  90       int stack = inferior_registers.r_reg[SP_REGNUM];
  91       int stuff = ptrace (PTRACE_PEEKDATA, inferior_pid,
  92                           (PTRACE_ARG3_TYPE) stack);
  93       int reg = inferior_registers.r_reg[EAX];
  94       inferior_registers.r_reg[EAX] =
  95         inferior_registers.r_reg[FP_REGNUM];
  96       ptrace (PTRACE_SETREGS, inferior_pid,
  97               (PTRACE_ARG3_TYPE) &inferior_registers);
  98       ptrace (PTRACE_POKEDATA, inferior_pid, (PTRACE_ARG3_TYPE) stack, 0xc589);
  99       ptrace (PTRACE_SINGLESTEP, inferior_pid, (PTRACE_ARG3_TYPE) stack, 0);
 100       wait (0);
 101       ptrace (PTRACE_POKEDATA, inferior_pid, (PTRACE_ARG3_TYPE) stack, stuff);
 102       inferior_registers.r_reg[EAX] = reg;
 103     }
 104 #endif
 105   ptrace (PTRACE_SETREGS, inferior_pid,
 106           (PTRACE_ARG3_TYPE) &inferior_registers);
 107   ptrace (PTRACE_SETFPREGS, inferior_pid,
 108           (PTRACE_ARG3_TYPE) &inferior_fp_registers);
 109 }
 110
 111
 112
 113 /* Work with core files, for GDB. */
 114
 115 void
 116 fetch_core_registers (core_reg_sect, core_reg_size, which, reg_addr)
 117      char *core_reg_sect;
 118      unsigned core_reg_size;
 119      int which;
 120      unsigned int reg_addr;     /* Unused in this version */
 121 {
 122   int val;
 123   extern char registers[];
 124
 125   switch (which) {
 126   case 0:
 127   case 1:
 128     bcopy (core_reg_sect, registers, core_reg_size);
 129     break;
 130
 131   case 2:
 132 #ifdef FP0_REGNUM
 133     bcopy (core_reg_sect,
 134            &registers[REGISTER_BYTE (FP0_REGNUM)],
 135            core_reg_size);              /* FIXME, probably bogus */
 136 #endif
 137 #ifdef FPC_REGNUM
 138     bcopy (&corestr.c_fpu.f_fpstatus.f_ctrl,
 139            &registers[REGISTER_BYTE (FPC_REGNUM)],
 140            sizeof corestr.c_fpu.f_fpstatus -
 141            sizeof corestr.c_fpu.f_fpstatus.f_st);
 142 #endif
 143     break;
 144   }
 145 }