gdb/i386obsd-tdep.c

   1 /* Target-dependent code for OpenBSD/i386.
   2
   3    Copyright 1988, 1989, 1991, 1992, 1994, 1996, 2000, 2001, 2002,
   4    2003, 2004
   5    Free Software Foundation, Inc.
   6
   7    This file is part of GDB.
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 2 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program; if not, write to the Free Software
  21    Foundation, Inc., 59 Temple Place - Suite 330,
  22    Boston, MA 02111-1307, USA.  */
  23
  24 #include "defs.h"
  25 #include "arch-utils.h"
  26 #include "gdbcore.h"
  27 #include "regcache.h"
  28 #include "regset.h"
  29 #include "osabi.h"
  30
  31 #include "gdb_assert.h"
  32 #include "gdb_string.h"
  33
  34 #include "i386-tdep.h"
  35 #include "i387-tdep.h"
  36 #include "solib-svr4.h"
  37
  38 /* From <machine/reg.h>.  */
  39 static int i386obsd_r_reg_offset[] =
  40 {
  41   0 * 4,                        /* %eax */
  42   1 * 4,                        /* %ecx */
  43   2 * 4,                        /* %edx */
  44   3 * 4,                        /* %ebx */
  45   4 * 4,                        /* %esp */
  46   5 * 4,                        /* %ebp */
  47   6 * 4,                        /* %esi */
  48   7 * 4,                        /* %edi */
  49   8 * 4,                        /* %eip */
  50   9 * 4,                        /* %eflags */
  51   10 * 4,                       /* %cs */
  52   11 * 4,                       /* %ss */
  53   12 * 4,                       /* %ds */
  54   13 * 4,                       /* %es */
  55   14 * 4,                       /* %fs */
  56   15 * 4                        /* %gs */
  57 };
  58
  59 static void
  60 i386obsd_aout_supply_regset (const struct regset *regset,
  61                              struct regcache *regcache, int regnum,
  62                              const void *regs, size_t len)
  63 {
  64   const struct gdbarch_tdep *tdep = regset->descr;
  65
  66   gdb_assert (len >= tdep->sizeof_gregset + I387_SIZEOF_FSAVE);
  67
  68   i386_supply_gregset (regset, regcache, regnum, regs, tdep->sizeof_gregset);
  69   i387_supply_fsave (regcache, regnum, (char *) regs + tdep->sizeof_gregset);
  70 }
  71
  72 static const struct regset *
  73 i386obsd_aout_regset_from_core_section (struct gdbarch *gdbarch,
  74                                         const char *sect_name,
  75                                         size_t sect_size)
  76 {
  77   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
  78
  79   /* OpenBSD a.out core dumps don't use seperate register sets for the
  80      general-purpose and floating-point registers.  */
  81
  82   if (strcmp (sect_name, ".reg") == 0
  83       && sect_size >= tdep->sizeof_gregset + I387_SIZEOF_FSAVE)
  84     {
  85       if (tdep->gregset == NULL)
  86         {
  87           tdep->gregset = XMALLOC (struct regset);
  88           tdep->gregset->descr = tdep;
  89           tdep->gregset->supply_regset = i386obsd_aout_supply_regset;
  90         }
  91       return tdep->gregset;
  92     }
  93
  94   return NULL;
  95 }
  96 \f
  97
  98 CORE_ADDR i386obsd_sigtramp_start = 0xbfbfdf20;
  99 CORE_ADDR i386obsd_sigtramp_end = 0xbfbfdff0;
 100
 101 /* From <machine/signal.h>.  */
 102 int i386obsd_sc_reg_offset[I386_NUM_GREGS] =
 103 {
 104   10 * 4,                       /* %eax */
 105   9 * 4,                        /* %ecx */
 106   8 * 4,                        /* %edx */
 107   7 * 4,                        /* %ebx */
 108   14 * 4,                       /* %esp */
 109   6 * 4,                        /* %ebp */
 110   5 * 4,                        /* %esi */
 111   4 * 4,                        /* %edi */
 112   11 * 4,                       /* %eip */
 113   13 * 4,                       /* %eflags */
 114   12 * 4,                       /* %cs */
 115   15 * 4,                       /* %ss */
 116   3 * 4,                        /* %ds */
 117   2 * 4,                        /* %es */
 118   1 * 4,                        /* %fs */
 119   0 * 4                         /* %gs */
 120 };
 121
 122 static void
 123 i386obsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 124 {
 125   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 126
 127   /* Obviously OpenBSD is BSD-based.  */
 128   i386bsd_init_abi (info, gdbarch);
 129
 130   /* OpenBSD has a different `struct reg'.  */
 131   tdep->gregset_reg_offset = i386obsd_r_reg_offset;
 132   tdep->gregset_num_regs = ARRAY_SIZE (i386obsd_r_reg_offset);
 133   tdep->sizeof_gregset = 16 * 4;
 134
 135   /* OpenBSD uses -freg-struct-return by default.  */
 136   tdep->struct_return = reg_struct_return;
 137
 138   /* OpenBSD uses a different memory layout.  */
 139   tdep->sigtramp_start = i386obsd_sigtramp_start;
 140   tdep->sigtramp_end = i386obsd_sigtramp_end;
 141
 142   /* OpenBSD has a `struct sigcontext' that's different from the
 143      origional 4.3 BSD.  */
 144   tdep->sc_reg_offset = i386obsd_sc_reg_offset;
 145   tdep->sc_num_regs = ARRAY_SIZE (i386obsd_sc_reg_offset);
 146 }
 147
 148 /* OpenBSD a.out.  */
 149
 150 static void
 151 i386obsd_aout_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 152 {
 153   i386obsd_init_abi (info, gdbarch);
 154
 155   /* OpenBSD a.out has a single register set.  */
 156   set_gdbarch_regset_from_core_section
 157     (gdbarch, i386obsd_aout_regset_from_core_section);
 158 }
 159
 160 /* OpenBSD ELF.  */
 161
 162 static void
 163 i386obsd_elf_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 164 {
 165   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 166
 167   /* It's still OpenBSD.  */
 168   i386obsd_init_abi (info, gdbarch);
 169
 170   /* But ELF-based.  */
 171   i386_elf_init_abi (info, gdbarch);
 172
 173   /* OpenBSD ELF uses SVR4-style shared libraries.  */
 174   set_gdbarch_in_solib_call_trampoline
 175     (gdbarch, generic_in_solib_call_trampoline);
 176   set_solib_svr4_fetch_link_map_offsets
 177     (gdbarch, svr4_ilp32_fetch_link_map_offsets);
 178 }
 179 \f
 180
 181 /* Provide a prototype to silence -Wmissing-prototypes.  */
 182 void _initialize_i386obsd_tdep (void);
 183
 184 void
 185 _initialize_i386obsd_tdep (void)
 186 {
 187   /* FIXME: kettenis/20021020: Since OpenBSD/i386 binaries are
 188      indistingushable from NetBSD/i386 a.out binaries, building a GDB
 189      that should support both these targets will probably not work as
 190      expected.  */
 191 #define GDB_OSABI_OPENBSD_AOUT GDB_OSABI_NETBSD_AOUT
 192
 193   gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_OPENBSD_AOUT,
 194                           i386obsd_aout_init_abi);
 195   gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_OPENBSD_ELF,
 196                           i386obsd_elf_init_abi);
 197 }