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 /* Return whether PC is in a BSD sigtramp routine.  */
  36
  37 int
  38 i386bsd_pc_in_sigtramp (CORE_ADDR pc, char *name)
  39 {
  40   struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
  41
  42   return (pc >= tdep->sigtramp_start && pc < tdep->sigtramp_end);
  43 }
  44
  45 /* Assuming NEXT_FRAME is for a frame following a BSD sigtramp
  46    routine, return the address of the associated sigcontext structure.  */
  47
  48 static CORE_ADDR
  49 i386bsd_sigcontext_addr (struct frame_info *next_frame)
  50 {
  51   char buf[4];
  52   CORE_ADDR sp;
  53
  54   frame_unwind_register (next_frame, I386_ESP_REGNUM, buf);
  55   sp = extract_unsigned_integer (buf, 4);
  56
  57   return read_memory_unsigned_integer (sp + 8, 4);
  58 }
  59
  60 /* Return the start address of the sigtramp routine.  */
  61
  62 CORE_ADDR
  63 i386bsd_sigtramp_start (CORE_ADDR pc)
  64 {
  65   return gdbarch_tdep (current_gdbarch)->sigtramp_start;
  66 }
  67
  68 /* Return the end address of the sigtramp routine.  */
  69
  70 CORE_ADDR
  71 i386bsd_sigtramp_end (CORE_ADDR pc)
  72 {
  73   return gdbarch_tdep (current_gdbarch)->sigtramp_end;
  74 }
  75 \f
  76
  77 /* Support for shared libraries.  */
  78
  79 /* Return non-zero if we are in a shared library trampoline code stub.  */
  80
  81 int
  82 i386bsd_aout_in_solib_call_trampoline (CORE_ADDR pc, char *name)
  83 {
  84   return (name && !strcmp (name, "_DYNAMIC"));
  85 }
  86
  87 /* Traditional BSD (4.3 BSD, still used for BSDI and 386BSD).  */
  88
  89 /* From <machine/signal.h>.  */
  90 int i386bsd_sc_reg_offset[] =
  91 {
  92   -1,                           /* %eax */
  93   -1,                           /* %ecx */
  94   -1,                           /* %edx */
  95   -1,                           /* %ebx */
  96   8 + 0 * 4,                    /* %esp */
  97   8 + 1 * 4,                    /* %ebp */
  98   -1,                           /* %esi */
  99   -1,                           /* %edi */
 100   8 + 3 * 4,                    /* %eip */
 101   8 + 4 * 4,                    /* %eflags */
 102   -1,                           /* %cs */
 103   -1,                           /* %ss */
 104   -1,                           /* %ds */
 105   -1,                           /* %es */
 106   -1,                           /* %fs */
 107   -1                            /* %gs */
 108 };
 109
 110 void
 111 i386bsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 112 {
 113   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 114
 115   set_gdbarch_pc_in_sigtramp (gdbarch, i386bsd_pc_in_sigtramp);
 116
 117   /* Allow the recognition of sigtramps as a function named <sigtramp>.  */
 118   set_gdbarch_sigtramp_start (gdbarch, i386bsd_sigtramp_start);
 119   set_gdbarch_sigtramp_end (gdbarch, i386bsd_sigtramp_end);
 120
 121   /* Assume SunOS-style shared libraries.  */
 122   set_gdbarch_in_solib_call_trampoline (gdbarch,
 123                                         i386bsd_aout_in_solib_call_trampoline);
 124
 125   tdep->jb_pc_offset = 0;
 126
 127   tdep->sigtramp_start = 0xfdbfdfc0;
 128   tdep->sigtramp_end = 0xfdbfe000;
 129   tdep->sigcontext_addr = i386bsd_sigcontext_addr;
 130   tdep->sc_reg_offset = i386bsd_sc_reg_offset;
 131   tdep->sc_num_regs = ARRAY_SIZE (i386bsd_sc_reg_offset);
 132 }
 133
 134 \f
 135 static enum gdb_osabi
 136 i386bsd_aout_osabi_sniffer (bfd *abfd)
 137 {
 138   if (strcmp (bfd_get_target (abfd), "a.out-i386-netbsd") == 0)
 139     return GDB_OSABI_NETBSD_AOUT;
 140
 141   if (strcmp (bfd_get_target (abfd), "a.out-i386-freebsd") == 0)
 142     return GDB_OSABI_FREEBSD_AOUT;
 143
 144   return GDB_OSABI_UNKNOWN;
 145 }
 146
 147 static enum gdb_osabi
 148 i386bsd_core_osabi_sniffer (bfd *abfd)
 149 {
 150   if (strcmp (bfd_get_target (abfd), "netbsd-core") == 0)
 151     return GDB_OSABI_NETBSD_AOUT;
 152
 153   return GDB_OSABI_UNKNOWN;
 154 }
 155
 156 \f
 157 /* Provide a prototype to silence -Wmissing-prototypes.  */
 158 void _initialize_i386bsd_tdep (void);
 159
 160 void
 161 _initialize_i386bsd_tdep (void)
 162 {
 163   gdbarch_register_osabi_sniffer (bfd_arch_i386, bfd_target_aout_flavour,
 164                                   i386bsd_aout_osabi_sniffer);
 165
 166   /* BFD doesn't set a flavour for NetBSD style a.out core files.  */
 167   gdbarch_register_osabi_sniffer (bfd_arch_i386, bfd_target_unknown_flavour,
 168                                   i386bsd_core_osabi_sniffer);
 169 }