aboutsummaryrefslogtreecommitdiff
path: root/gdb/i386bsd-tdep.c
blob: 80e057b4fa389446160075bba3ec4e396219fa58 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
/* Target-dependent code for i386 BSD's.
   Copyright 2001, 2002, 2003 Free Software Foundation, Inc.

   This file is part of GDB.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#include "defs.h"
#include "arch-utils.h"
#include "frame.h"
#include "gdbcore.h"
#include "regcache.h"
#include "osabi.h"

#include "gdb_string.h"

#include "i386-tdep.h"

/* Support for signal handlers.  */

/* Return whether PC is in a BSD sigtramp routine.  */

static int
i386bsd_pc_in_sigtramp (CORE_ADDR pc, char *name)
{
  struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);

  return (pc >= tdep->sigtramp_start && pc < tdep->sigtramp_end);
}

/* Assuming NEXT_FRAME is for a frame following a BSD sigtramp
   routine, return the address of the associated sigcontext structure.  */

static CORE_ADDR
i386bsd_sigcontext_addr (struct frame_info *next_frame)
{
  char buf[4];
  CORE_ADDR sp;

  frame_unwind_register (next_frame, SP_REGNUM, buf);
  sp = extract_unsigned_integer (buf, 4);

  return read_memory_unsigned_integer (sp + 8, 4);
}

/* Return the start address of the sigtramp routine.  */

CORE_ADDR
i386bsd_sigtramp_start (CORE_ADDR pc)
{
  return gdbarch_tdep (current_gdbarch)->sigtramp_start;
}

/* Return the end address of the sigtramp routine.  */

CORE_ADDR
i386bsd_sigtramp_end (CORE_ADDR pc)
{
  return gdbarch_tdep (current_gdbarch)->sigtramp_end;
}


/* Support for shared libraries.  */

/* Return non-zero if we are in a shared library trampoline code stub.  */

int
i386bsd_aout_in_solib_call_trampoline (CORE_ADDR pc, char *name)
{
  return (name && !strcmp (name, "_DYNAMIC"));
}

/* Traditional BSD (4.3 BSD, still used for BSDI and 386BSD).  */

/* From <machine/signal.h>.  */
int i386bsd_sc_reg_offset[I386_NUM_GREGS] =
{
  -1,				/* %eax */
  -1,				/* %ecx */
  -1,				/* %edx */
  -1,				/* %ebx */
  8 + 0 * 4,			/* %esp */
  8 + 1 * 4,			/* %ebp */
  -1,				/* %esi */
  -1,				/* %edi */
  8 + 3 * 4,			/* %eip */
  8 + 4 * 4,			/* %eflags */
  -1,				/* %cs */
  -1,				/* %ss */
  -1,				/* %ds */
  -1,				/* %es */
  -1,				/* %fs */
  -1				/* %gs */
};

void
i386bsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
{
  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);

  set_gdbarch_pc_in_sigtramp (gdbarch, i386bsd_pc_in_sigtramp);

  /* Allow the recognition of sigtramps as a function named <sigtramp>.  */
  set_gdbarch_sigtramp_start (gdbarch, i386bsd_sigtramp_start);
  set_gdbarch_sigtramp_end (gdbarch, i386bsd_sigtramp_end);

  /* Assume SunOS-style shared libraries.  */
  set_gdbarch_in_solib_call_trampoline (gdbarch,
					i386bsd_aout_in_solib_call_trampoline);

  tdep->jb_pc_offset = 0;

  tdep->sigtramp_start = 0xfdbfdfc0;
  tdep->sigtramp_end = 0xfdbfe000;
  tdep->sigcontext_addr = i386bsd_sigcontext_addr;
  tdep->sc_reg_offset = i386bsd_sc_reg_offset;
  tdep->sc_num_regs = I386_NUM_GREGS;
}

/* FreeBSD 3.0-RELEASE or later.  */

CORE_ADDR i386fbsd_sigtramp_start = 0xbfbfdf20;
CORE_ADDR i386fbsd_sigtramp_end = 0xbfbfdff0;

/* From <machine/signal.h>.  */
int i386fbsd_sc_reg_offset[I386_NUM_GREGS] =
{
  8 + 14 * 4,			/* %eax */
  8 + 13 * 4,			/* %ecx */
  8 + 12 * 4,			/* %edx */
  8 + 11 * 4,			/* %ebx */
  8 + 0 * 4,                    /* %esp */
  8 + 1 * 4,                    /* %ebp */
  8 + 10 * 4,                   /* %esi */
  8 + 9 * 4,                    /* %edi */
  8 + 3 * 4,                    /* %eip */
  8 + 4 * 4,                    /* %eflags */
  8 + 7 * 4,                    /* %cs */
  8 + 8 * 4,                    /* %ss */
  8 + 6 * 4,                    /* %ds */
  8 + 5 * 4,                    /* %es */
  8 + 15 * 4,			/* %fs */
  8 + 16 * 4			/* %gs */
};

static void
i386fbsdaout_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
{
  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);

  /* Obviously FreeBSD is BSD-based.  */
  i386bsd_init_abi (info, gdbarch);

  /* FreeBSD uses -freg-struct-return by default.  */
  tdep->struct_return = reg_struct_return;

  /* FreeBSD uses a different memory layout.  */
  tdep->sigtramp_start = i386fbsd_sigtramp_start;
  tdep->sigtramp_end = i386fbsd_sigtramp_end;

  /* FreeBSD has a more complete `struct sigcontext'.  */
  tdep->sc_reg_offset = i386fbsd_sc_reg_offset;
  tdep->sc_num_regs = I386_NUM_GREGS;
}

static void
i386fbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
{
  /* It's almost identical to FreeBSD a.out.  */
  i386fbsdaout_init_abi (info, gdbarch);

  /* Except that it uses ELF.  */
  i386_elf_init_abi (info, gdbarch);

  /* FreeBSD ELF uses SVR4-style shared libraries.  */
  set_gdbarch_in_solib_call_trampoline (gdbarch,
					generic_in_solib_call_trampoline);
}

/* FreeBSD 4.0-RELEASE or later.  */

/* From <machine/signal.h>.  */
int i386fbsd4_sc_reg_offset[I386_NUM_GREGS] =
{
  20 + 11 * 4,			/* %eax */
  20 + 10 * 4,			/* %ecx */
  20 + 9 * 4,			/* %edx */
  20 + 8 * 4,			/* %ebx */
  20 + 17 * 4,			/* %esp */
  20 + 6 * 4,			/* %ebp */
  20 + 5 * 4,			/* %esi */
  20 + 4 * 4,			/* %edi */
  20 + 14 * 4,			/* %eip */
  20 + 16 * 4,			/* %eflags */
  20 + 15 * 4,			/* %cs */
  20 + 18 * 4,			/* %ss */
  20 + 3 * 4,			/* %ds */
  20 + 2 * 4,			/* %es */
  20 + 1 * 4,			/* %fs */
  20 + 0 * 4			/* %gs */
};

static void
i386fbsd4_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
{
  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);

  /* Inherit stuff from older releases.  We assume that FreeBSD
     4.0-RELEASE always uses ELF.  */
  i386fbsd_init_abi (info, gdbarch);

  /* FreeBSD 4.0 introduced a new `struct sigcontext'.  */
  tdep->sc_reg_offset = i386fbsd4_sc_reg_offset;
  tdep->sc_num_regs = I386_NUM_GREGS;
}


static enum gdb_osabi
i386bsd_aout_osabi_sniffer (bfd *abfd)
{
  if (strcmp (bfd_get_target (abfd), "a.out-i386-netbsd") == 0)
    return GDB_OSABI_NETBSD_AOUT;

  if (strcmp (bfd_get_target (abfd), "a.out-i386-freebsd") == 0)
    return GDB_OSABI_FREEBSD_AOUT;

  return GDB_OSABI_UNKNOWN;
}


/* Provide a prototype to silence -Wmissing-prototypes.  */
void _initialize_i386bsd_tdep (void);

void
_initialize_i386bsd_tdep (void)
{
  gdbarch_register_osabi_sniffer (bfd_arch_i386, bfd_target_aout_flavour,
				  i386bsd_aout_osabi_sniffer);

  gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_FREEBSD_AOUT,
			  i386fbsdaout_init_abi);
  gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_FREEBSD_ELF,
			  i386fbsd4_init_abi);
}