gdb/i386bsd-tdep.c

   1 /* Target-dependent code for i386 BSD's.
   2
   3    Copyright (C) 2001, 2002, 2003, 2004, 2007, 2008, 2009, 2010, 2011
   4    Free Software Foundation, Inc.
   5
   6    This file is part of GDB.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  20
  21 #include "defs.h"
  22 #include "arch-utils.h"
  23 #include "frame.h"
  24 #include "gdbcore.h"
  25 #include "regcache.h"
  26 #include "osabi.h"
  27
  28 #include "gdb_string.h"
  29
  30 #include "i386-tdep.h"
  31
  32 /* Support for signal handlers.  */
  33
  34 /* Assuming THIS_FRAME is for a BSD sigtramp routine, return the
  35    address of the associated sigcontext structure.  */
  36
  37 static CORE_ADDR
  38 i386bsd_sigcontext_addr (struct frame_info *this_frame)
  39 {
  40   struct gdbarch *gdbarch = get_frame_arch (this_frame);
  41   enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
  42   gdb_byte buf[4];
  43   CORE_ADDR sp;
  44
  45   get_frame_register (this_frame, I386_ESP_REGNUM, buf);
  46   sp = extract_unsigned_integer (buf, 4, byte_order);
  47
  48   return read_memory_unsigned_integer (sp + 8, 4, byte_order);
  49 }
  50 \f
  51
  52 /* Support for shared libraries.  */
  53
  54 /* Traditional BSD (4.3 BSD, still used for BSDI and 386BSD).  */
  55
  56 /* From <machine/signal.h>.  */
  57 int i386bsd_sc_reg_offset[] =
  58 {
  59   -1,                           /* %eax */
  60   -1,                           /* %ecx */
  61   -1,                           /* %edx */
  62   -1,                           /* %ebx */
  63   8 + 0 * 4,                    /* %esp */
  64   8 + 1 * 4,                    /* %ebp */
  65   -1,                           /* %esi */
  66   -1,                           /* %edi */
  67   8 + 3 * 4,                    /* %eip */
  68   8 + 4 * 4,                    /* %eflags */
  69   -1,                           /* %cs */
  70   -1,                           /* %ss */
  71   -1,                           /* %ds */
  72   -1,                           /* %es */
  73   -1,                           /* %fs */
  74   -1                            /* %gs */
  75 };
  76
  77 void
  78 i386bsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
  79 {
  80   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
  81
  82   tdep->jb_pc_offset = 0;
  83
  84   tdep->sigtramp_start = 0xfdbfdfc0;
  85   tdep->sigtramp_end = 0xfdbfe000;
  86   tdep->sigcontext_addr = i386bsd_sigcontext_addr;
  87   tdep->sc_reg_offset = i386bsd_sc_reg_offset;
  88   tdep->sc_num_regs = ARRAY_SIZE (i386bsd_sc_reg_offset);
  89 }
  90
  91 \f
  92 static enum gdb_osabi
  93 i386bsd_aout_osabi_sniffer (bfd *abfd)
  94 {
  95   if (strcmp (bfd_get_target (abfd), "a.out-i386-netbsd") == 0)
  96     return GDB_OSABI_NETBSD_AOUT;
  97
  98   if (strcmp (bfd_get_target (abfd), "a.out-i386-freebsd") == 0)
  99     return GDB_OSABI_FREEBSD_AOUT;
 100
 101   return GDB_OSABI_UNKNOWN;
 102 }
 103
 104 static enum gdb_osabi
 105 i386bsd_core_osabi_sniffer (bfd *abfd)
 106 {
 107   if (strcmp (bfd_get_target (abfd), "netbsd-core") == 0)
 108     return GDB_OSABI_NETBSD_AOUT;
 109
 110   return GDB_OSABI_UNKNOWN;
 111 }
 112
 113 \f
 114 /* Provide a prototype to silence -Wmissing-prototypes.  */
 115 void _initialize_i386bsd_tdep (void);
 116
 117 void
 118 _initialize_i386bsd_tdep (void)
 119 {
 120   gdbarch_register_osabi_sniffer (bfd_arch_i386, bfd_target_aout_flavour,
 121                                   i386bsd_aout_osabi_sniffer);
 122
 123   /* BFD doesn't set a flavour for NetBSD style a.out core files.  */
 124   gdbarch_register_osabi_sniffer (bfd_arch_i386, bfd_target_unknown_flavour,
 125                                   i386bsd_core_osabi_sniffer);
 126 }