gdb/i386bsd-tdep.c

   1 /* Target-dependent code for i386 BSD's.
   2
   3    Copyright 2001, 2002, 2003, 2004 Free Software 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 "arch-utils.h"
  24 #include "frame.h"
  25 #include "gdbcore.h"
  26 #include "regcache.h"
  27 #include "osabi.h"
  28
  29 #include "gdb_string.h"
  30
  31 #include "i386-tdep.h"
  32
  33 /* Support for signal handlers.  */
  34
  35 /* Assuming NEXT_FRAME is for a frame following a BSD sigtramp
  36    routine, return the address of the associated sigcontext structure.  */
  37
  38 static CORE_ADDR
  39 i386bsd_sigcontext_addr (struct frame_info *next_frame)
  40 {
  41   char buf[4];
  42   CORE_ADDR sp;
  43
  44   frame_unwind_register (next_frame, I386_ESP_REGNUM, buf);
  45   sp = extract_unsigned_integer (buf, 4);
  46
  47   return read_memory_unsigned_integer (sp + 8, 4);
  48 }
  49 \f
  50
  51 /* Support for shared libraries.  */
  52
  53 /* Return non-zero if we are in a shared library trampoline code stub.  */
  54
  55 int
  56 i386bsd_aout_in_solib_call_trampoline (CORE_ADDR pc, char *name)
  57 {
  58   return (name && !strcmp (name, "_DYNAMIC"));
  59 }
  60
  61 /* Traditional BSD (4.3 BSD, still used for BSDI and 386BSD).  */
  62
  63 /* From <machine/signal.h>.  */
  64 int i386bsd_sc_reg_offset[] =
  65 {
  66   -1,                           /* %eax */
  67   -1,                           /* %ecx */
  68   -1,                           /* %edx */
  69   -1,                           /* %ebx */
  70   8 + 0 * 4,                    /* %esp */
  71   8 + 1 * 4,                    /* %ebp */
  72   -1,                           /* %esi */
  73   -1,                           /* %edi */
  74   8 + 3 * 4,                    /* %eip */
  75   8 + 4 * 4,                    /* %eflags */
  76   -1,                           /* %cs */
  77   -1,                           /* %ss */
  78   -1,                           /* %ds */
  79   -1,                           /* %es */
  80   -1,                           /* %fs */
  81   -1                            /* %gs */
  82 };
  83
  84 void
  85 i386bsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
  86 {
  87   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
  88
  89   /* Assume SunOS-style shared libraries.  */
  90   set_gdbarch_in_solib_call_trampoline (gdbarch,
  91                                         i386bsd_aout_in_solib_call_trampoline);
  92
  93   tdep->jb_pc_offset = 0;
  94
  95   tdep->sigtramp_start = 0xfdbfdfc0;
  96   tdep->sigtramp_end = 0xfdbfe000;
  97   tdep->sigcontext_addr = i386bsd_sigcontext_addr;
  98   tdep->sc_reg_offset = i386bsd_sc_reg_offset;
  99   tdep->sc_num_regs = ARRAY_SIZE (i386bsd_sc_reg_offset);
 100 }
 101
 102 \f
 103 static enum gdb_osabi
 104 i386bsd_aout_osabi_sniffer (bfd *abfd)
 105 {
 106   if (strcmp (bfd_get_target (abfd), "a.out-i386-netbsd") == 0)
 107     return GDB_OSABI_NETBSD_AOUT;
 108
 109   if (strcmp (bfd_get_target (abfd), "a.out-i386-freebsd") == 0)
 110     return GDB_OSABI_FREEBSD_AOUT;
 111
 112   return GDB_OSABI_UNKNOWN;
 113 }
 114
 115 static enum gdb_osabi
 116 i386bsd_core_osabi_sniffer (bfd *abfd)
 117 {
 118   if (strcmp (bfd_get_target (abfd), "netbsd-core") == 0)
 119     return GDB_OSABI_NETBSD_AOUT;
 120
 121   return GDB_OSABI_UNKNOWN;
 122 }
 123
 124 \f
 125 /* Provide a prototype to silence -Wmissing-prototypes.  */
 126 void _initialize_i386bsd_tdep (void);
 127
 128 void
 129 _initialize_i386bsd_tdep (void)
 130 {
 131   gdbarch_register_osabi_sniffer (bfd_arch_i386, bfd_target_aout_flavour,
 132                                   i386bsd_aout_osabi_sniffer);
 133
 134   /* BFD doesn't set a flavour for NetBSD style a.out core files.  */
 135   gdbarch_register_osabi_sniffer (bfd_arch_i386, bfd_target_unknown_flavour,
 136                                   i386bsd_core_osabi_sniffer);
 137 }