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,
  19    Boston, MA 02111-1307, USA.  */
  20
  21 #include "defs.h"
  22 #include "frame.h"
  23 #include "inferior.h"
  24 #include "gdbcore.h"
  25
  26 #include <sys/param.h>
  27 #include <sys/dir.h>
  28 #include <sys/user.h>
  29 #include <signal.h>
  30 #include <sys/ioctl.h>
  31 #include <fcntl.h>
  32
  33 #include <sys/ptrace.h>
  34 #include <machine/reg.h>
  35
  36 #include <sys/file.h>
  37 #include "gdb_stat.h"
  38 #include <sys/core.h>
  39
  40 static void fetch_core_registers (char *, unsigned, int, CORE_ADDR);
  41
  42 void
  43 fetch_inferior_registers (int regno)
  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 (int regno)
  71 {
  72   struct regs inferior_registers;
  73   struct fp_state inferior_fp_registers;
  74
  75   memcpy (&inferior_registers, registers, 20 * 4);
  76
  77   memcpy (inferior_fp_registers.f_st, &registers[REGISTER_BYTE (FP0_REGNUM)],
  78           sizeof inferior_fp_registers.f_st);
  79   memcpy (&inferior_fp_registers.f_ctrl,
  80           &registers[REGISTER_BYTE (FPC_REGNUM)],
  81           sizeof inferior_fp_registers - sizeof inferior_fp_registers.f_st);
  82
  83 #ifdef PTRACE_FP_BUG
  84   if (regno == FP_REGNUM || regno == -1)
  85     /* Storing the frame pointer requires a gross hack, in which an
  86        instruction that moves eax into ebp gets single-stepped.  */
  87     {
  88       int stack = inferior_registers.r_reg[SP_REGNUM];
  89       int stuff = ptrace (PTRACE_PEEKDATA, inferior_pid,
  90                           (PTRACE_ARG3_TYPE) stack);
  91       int reg = inferior_registers.r_reg[EAX];
  92       inferior_registers.r_reg[EAX] =
  93         inferior_registers.r_reg[FP_REGNUM];
  94       ptrace (PTRACE_SETREGS, inferior_pid,
  95               (PTRACE_ARG3_TYPE) & inferior_registers);
  96       ptrace (PTRACE_POKEDATA, inferior_pid, (PTRACE_ARG3_TYPE) stack, 0xc589);
  97       ptrace (PTRACE_SINGLESTEP, inferior_pid, (PTRACE_ARG3_TYPE) stack, 0);
  98       wait (0);
  99       ptrace (PTRACE_POKEDATA, inferior_pid, (PTRACE_ARG3_TYPE) stack, stuff);
 100       inferior_registers.r_reg[EAX] = reg;
 101     }
 102 #endif
 103   ptrace (PTRACE_SETREGS, inferior_pid,
 104           (PTRACE_ARG3_TYPE) & inferior_registers);
 105   ptrace (PTRACE_SETFPREGS, inferior_pid,
 106           (PTRACE_ARG3_TYPE) & inferior_fp_registers);
 107 }
 108
 109
 110
 111 /* Provide registers to GDB from a core file.
 112
 113    CORE_REG_SECT points to an array of bytes, which were obtained from
 114    a core file which BFD thinks might contain register contents.
 115    CORE_REG_SIZE is its size.
 116
 117    WHICH says which register set corelow suspects this is:
 118      0 --- the general-purpose register set
 119      2 --- the floating-point register set
 120
 121    REG_ADDR isn't used.  */
 122
 123 static void
 124 fetch_core_registers (char *core_reg_sect, unsigned core_reg_size,
 125                       int which, CORE_ADDR reg_addr)
 126 {
 127   int val;
 128
 129   switch (which)
 130     {
 131     case 0:
 132     case 1:
 133       memcpy (registers, core_reg_sect, core_reg_size);
 134       break;
 135
 136     case 2:
 137       memcpy (&registers[REGISTER_BYTE (FP0_REGNUM)],
 138               core_reg_sect,
 139               core_reg_size);   /* FIXME, probably bogus */
 140 #ifdef FPC_REGNUM
 141       memcpy (&registers[REGISTER_BYTE (FPC_REGNUM)],
 142               &corestr.c_fpu.f_fpstatus.f_ctrl,
 143               sizeof corestr.c_fpu.f_fpstatus -
 144               sizeof corestr.c_fpu.f_fpstatus.f_st);
 145 #endif
 146       break;
 147     }
 148 }
 149 \f
 150
 151 /* Register that we are able to handle i386mach core file formats.
 152    FIXME: is this really bfd_target_unknown_flavour? */
 153
 154 static struct core_fns i386mach_core_fns =
 155 {
 156   bfd_target_unknown_flavour,           /* core_flavour */
 157   default_check_format,                 /* check_format */
 158   default_core_sniffer,                 /* core_sniffer */
 159   fetch_core_registers,                 /* core_read_registers */
 160   NULL                                  /* next */
 161 };
 162
 163 void
 164 _initialize_core_i386mach (void)
 165 {
 166   add_core_fns (&i386mach_core_fns);
 167 }