gdb/i386mach-nat.c

   1 /* Native dependent code for Mach 386's for GDB, the GNU debugger.
   2    Copyright 1986, 1987, 1989, 1991, 1992, 2001 Free Software
   3    Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, USA.  */
  21
  22 #include "defs.h"
  23 #include "frame.h"
  24 #include "inferior.h"
  25 #include "gdbcore.h"
  26 #include "regcache.h"
  27
  28 #include <sys/param.h>
  29 #include <sys/dir.h>
  30 #include <sys/user.h>
  31 #include <signal.h>
  32 #include <sys/ioctl.h>
  33 #include <fcntl.h>
  34
  35 #include <sys/ptrace.h>
  36 #include <machine/reg.h>
  37
  38 #include <sys/file.h>
  39 #include "gdb_stat.h"
  40 #include <sys/core.h>
  41
  42 static void fetch_core_registers (char *, unsigned, int, CORE_ADDR);
  43
  44 void
  45 fetch_inferior_registers (int regno)
  46 {
  47   struct regs inferior_registers;
  48   struct fp_state inferior_fp_registers;
  49
  50   registers_fetched ();
  51
  52   ptrace (PTRACE_GETREGS, inferior_pid,
  53           (PTRACE_ARG3_TYPE) & inferior_registers);
  54   ptrace (PTRACE_GETFPREGS, inferior_pid,
  55           (PTRACE_ARG3_TYPE) & inferior_fp_registers);
  56
  57   memcpy (registers, &inferior_registers, sizeof inferior_registers);
  58
  59   memcpy (&registers[REGISTER_BYTE (FP0_REGNUM)],
  60           inferior_fp_registers.f_st,
  61           sizeof inferior_fp_registers.f_st);
  62   memcpy (&registers[REGISTER_BYTE (FPC_REGNUM)],
  63           &inferior_fp_registers.f_ctrl,
  64           sizeof inferior_fp_registers - sizeof inferior_fp_registers.f_st);
  65 }
  66
  67 /* Store our register values back into the inferior.
  68    If REGNO is -1, do this for all registers.
  69    Otherwise, REGNO specifies which register (so we can save time).  */
  70
  71 void
  72 store_inferior_registers (int regno)
  73 {
  74   struct regs inferior_registers;
  75   struct fp_state inferior_fp_registers;
  76
  77   memcpy (&inferior_registers, registers, 20 * 4);
  78
  79   memcpy (inferior_fp_registers.f_st, &registers[REGISTER_BYTE (FP0_REGNUM)],
  80           sizeof inferior_fp_registers.f_st);
  81   memcpy (&inferior_fp_registers.f_ctrl,
  82           &registers[REGISTER_BYTE (FPC_REGNUM)],
  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 /* Provide registers to GDB from a core file.
 114
 115    CORE_REG_SECT points to an array of bytes, which were obtained from
 116    a core file which BFD thinks might contain register contents.
 117    CORE_REG_SIZE is its size.
 118
 119    WHICH says which register set corelow suspects this is:
 120      0 --- the general-purpose register set
 121      2 --- the floating-point register set
 122
 123    REG_ADDR isn't used.  */
 124
 125 static void
 126 fetch_core_registers (char *core_reg_sect, unsigned core_reg_size,
 127                       int which, CORE_ADDR reg_addr)
 128 {
 129   int val;
 130
 131   switch (which)
 132     {
 133     case 0:
 134     case 1:
 135       memcpy (registers, core_reg_sect, core_reg_size);
 136       break;
 137
 138     case 2:
 139       memcpy (&registers[REGISTER_BYTE (FP0_REGNUM)],
 140               core_reg_sect,
 141               core_reg_size);   /* FIXME, probably bogus */
 142 #ifdef FPC_REGNUM
 143       memcpy (&registers[REGISTER_BYTE (FPC_REGNUM)],
 144               &corestr.c_fpu.f_fpstatus.f_ctrl,
 145               sizeof corestr.c_fpu.f_fpstatus -
 146               sizeof corestr.c_fpu.f_fpstatus.f_st);
 147 #endif
 148       break;
 149     }
 150 }
 151 \f
 152
 153 /* Register that we are able to handle i386mach core file formats.
 154    FIXME: is this really bfd_target_unknown_flavour? */
 155
 156 static struct core_fns i386mach_core_fns =
 157 {
 158   bfd_target_unknown_flavour,           /* core_flavour */
 159   default_check_format,                 /* check_format */
 160   default_core_sniffer,                 /* core_sniffer */
 161   fetch_core_registers,                 /* core_read_registers */
 162   NULL                                  /* next */
 163 };
 164
 165 void
 166 _initialize_core_i386mach (void)
 167 {
 168   add_core_fns (&i386mach_core_fns);
 169 }