1/* Native-dependent code for VAX UNIXen (including older BSD's).
2
3   Copyright (C) 2004, 2005, 2007 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 3 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, see <http://www.gnu.org/licenses/>.  */
19
20#include "defs.h"
21#include "inferior.h"
22
23#include "gdb_assert.h"
24#include <sys/types.h>
25#include <sys/dir.h>
26#include <sys/user.h>
27
28#ifdef HAVE_SYS_PTRACE_H
29#include <sys/ptrace.h>
30#endif
31
32#ifndef PT_READ_U
33#define PT_READ_U 3
34#endif
35
36#ifdef SYS_REG_H
37/* UNIX 32V and derivatives (including 3BSD).  */
38#include <sys/reg.h>
39#else
40/* 4.2BSD and derivatives.  */
41#include <machine/reg.h>
42#endif
43
44#include "vax-tdep.h"
45#include "inf-ptrace.h"
46
47/* Address of the user structure.  This is the the value for 32V; 3BSD
48   uses a different value, but hey, who's still using those systems?  */
49static CORE_ADDR vax_kernel_u_addr = 0x80020000;
50
51/* Location of the user's stored registers; usage is `u.u_ar0[XX]'.
52   For 4.2BSD and ULTRIX these are negative!  See <machine/reg.h>.  */
53static int vax_register_index[] =
54{
55  R0, R1, R2, R3, R4, R5,
56  R6, R7, R8, R9, R10, R11,
57  AP, FP, SP, PC, PS
58};
59
60static CORE_ADDR
61vax_register_u_addr (CORE_ADDR u_ar0, int regnum)
62{
63  gdb_assert (regnum >= 0 && regnum < ARRAY_SIZE (vax_register_index));
64
65  /* Type is `int *u_ar0'.  See <sys/user.h>.  */
66  return u_ar0 + vax_register_index[regnum - VAX_R0_REGNUM] * 4;
67}
68
69static CORE_ADDR
70vax_register_u_offset (struct gdbarch *gdbarch, int regnum, int store_p)
71{
72  size_t u_ar0_offset = offsetof (struct user, u_ar0);
73  CORE_ADDR u_ar0;
74  int pid;
75
76  errno = 0;
77  pid = PIDGET (inferior_ptid);
78  u_ar0 = ptrace (PT_READ_U, pid, u_ar0_offset, 0);
79  if (errno)
80    perror_with_name (_("Unable to determine location of registers"));
81
82  return vax_register_u_addr (u_ar0, regnum) - vax_kernel_u_addr;
83}
84
85
86#include <nlist.h>
87
88#ifndef _PATH_UNIX
89#define _PATH_UNIX "/vmunix"
90#endif
91
92/* Provide a prototype to silence -Wmissing-prototypes.  */
93void _initialize_vax_nat (void);
94
95void
96_initialize_vax_nat (void)
97{
98  struct nlist names[2];
99
100  names[0].n_name = "_u";
101  names[1].n_name = NULL;
102  if (nlist (_PATH_UNIX, names) == 0)
103    vax_kernel_u_addr = names[0].n_value;
104
105  add_target (inf_ptrace_trad_target (vax_register_u_offset));
106}
107