1 /* Native-dependent code for modern i386 BSD's.
3 Copyright (C) 2000-2016 Free Software Foundation, Inc.
5 This file is part of GDB.
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.
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.
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/>. */
25 #include <sys/types.h>
26 #include <sys/ptrace.h>
27 #include <machine/reg.h>
28 #include <machine/frame.h>
30 #include "i386-tdep.h"
31 #include "i387-tdep.h"
32 #include "x86bsd-nat.h"
33 #include "i386bsd-nat.h"
34 #include "inf-ptrace.h"
37 /* In older BSD versions we cannot get at some of the segment
38 registers. FreeBSD for example didn't support the %fs and %gs
39 registers until the 3.0 release. We have autoconf checks for their
40 presence, and deal gracefully with their absence. */
42 /* Offset in `struct reg' where MEMBER is stored. */
43 #define REG_OFFSET(member) offsetof (struct reg, member)
45 /* At i386bsd_reg_offset[REGNUM] you'll find the offset in `struct
46 reg' where the GDB register REGNUM is stored. Unsupported
47 registers are marked with `-1'. */
48 static int i386bsd_r_reg_offset
[] =
59 REG_OFFSET (r_eflags
),
64 #ifdef HAVE_STRUCT_REG_R_FS
69 #ifdef HAVE_STRUCT_REG_R_GS
76 /* Macro to determine if a register is fetched with PT_GETREGS. */
77 #define GETREGS_SUPPLIES(regnum) \
78 ((0 <= (regnum) && (regnum) <= 15))
80 #ifdef HAVE_PT_GETXMMREGS
81 /* Set to 1 if the kernel supports PT_GETXMMREGS. Initialized to -1
82 so that we try PT_GETXMMREGS the first time around. */
83 static int have_ptrace_xmmregs
= -1;
87 /* Supply the general-purpose registers in GREGS, to REGCACHE. */
90 i386bsd_supply_gregset (struct regcache
*regcache
, const void *gregs
)
92 const char *regs
= (const char *) gregs
;
95 for (regnum
= 0; regnum
< ARRAY_SIZE (i386bsd_r_reg_offset
); regnum
++)
97 int offset
= i386bsd_r_reg_offset
[regnum
];
100 regcache_raw_supply (regcache
, regnum
, regs
+ offset
);
104 /* Collect register REGNUM from REGCACHE and store its contents in
105 GREGS. If REGNUM is -1, collect and store all appropriate
109 i386bsd_collect_gregset (const struct regcache
*regcache
,
110 void *gregs
, int regnum
)
112 char *regs
= (char *) gregs
;
115 for (i
= 0; i
< ARRAY_SIZE (i386bsd_r_reg_offset
); i
++)
117 if (regnum
== -1 || regnum
== i
)
119 int offset
= i386bsd_r_reg_offset
[i
];
122 regcache_raw_collect (regcache
, i
, regs
+ offset
);
127 /* Fetch register REGNUM from the inferior. If REGNUM is -1, do this
128 for all registers (including the floating point registers). */
131 i386bsd_fetch_inferior_registers (struct target_ops
*ops
,
132 struct regcache
*regcache
, int regnum
)
134 if (regnum
== -1 || GETREGS_SUPPLIES (regnum
))
138 if (ptrace (PT_GETREGS
, get_ptrace_pid (inferior_ptid
),
139 (PTRACE_TYPE_ARG3
) ®s
, 0) == -1)
140 perror_with_name (_("Couldn't get registers"));
142 i386bsd_supply_gregset (regcache
, ®s
);
147 if (regnum
== -1 || regnum
>= I386_ST0_REGNUM
)
150 #ifdef HAVE_PT_GETXMMREGS
154 #ifdef PT_GETXSTATE_INFO
155 if (x86bsd_xsave_len
!= 0)
159 xstateregs
= alloca (x86bsd_xsave_len
);
160 if (ptrace (PT_GETXSTATE
, get_ptrace_pid (inferior_ptid
),
161 (PTRACE_TYPE_ARG3
) xstateregs
, 0) == -1)
162 perror_with_name (_("Couldn't get extended state status"));
164 i387_supply_xsave (regcache
, -1, xstateregs
);
169 #ifdef HAVE_PT_GETXMMREGS
170 if (have_ptrace_xmmregs
!= 0
171 && ptrace(PT_GETXMMREGS
, get_ptrace_pid (inferior_ptid
),
172 (PTRACE_TYPE_ARG3
) xmmregs
, 0) == 0)
174 have_ptrace_xmmregs
= 1;
175 i387_supply_fxsave (regcache
, -1, xmmregs
);
179 have_ptrace_xmmregs
= 0;
181 if (ptrace (PT_GETFPREGS
, get_ptrace_pid (inferior_ptid
),
182 (PTRACE_TYPE_ARG3
) &fpregs
, 0) == -1)
183 perror_with_name (_("Couldn't get floating point status"));
185 i387_supply_fsave (regcache
, -1, &fpregs
);
186 #ifdef HAVE_PT_GETXMMREGS
192 /* Store register REGNUM back into the inferior. If REGNUM is -1, do
193 this for all registers (including the floating point registers). */
196 i386bsd_store_inferior_registers (struct target_ops
*ops
,
197 struct regcache
*regcache
, int regnum
)
199 if (regnum
== -1 || GETREGS_SUPPLIES (regnum
))
203 if (ptrace (PT_GETREGS
, get_ptrace_pid (inferior_ptid
),
204 (PTRACE_TYPE_ARG3
) ®s
, 0) == -1)
205 perror_with_name (_("Couldn't get registers"));
207 i386bsd_collect_gregset (regcache
, ®s
, regnum
);
209 if (ptrace (PT_SETREGS
, get_ptrace_pid (inferior_ptid
),
210 (PTRACE_TYPE_ARG3
) ®s
, 0) == -1)
211 perror_with_name (_("Couldn't write registers"));
217 if (regnum
== -1 || regnum
>= I386_ST0_REGNUM
)
220 #ifdef HAVE_PT_GETXMMREGS
224 #ifdef PT_GETXSTATE_INFO
225 if (x86bsd_xsave_len
!= 0)
229 xstateregs
= alloca (x86bsd_xsave_len
);
230 if (ptrace (PT_GETXSTATE
, get_ptrace_pid (inferior_ptid
),
231 (PTRACE_TYPE_ARG3
) xstateregs
, 0) == -1)
232 perror_with_name (_("Couldn't get extended state status"));
234 i387_collect_xsave (regcache
, -1, xstateregs
, 0);
236 if (ptrace (PT_SETXSTATE
, get_ptrace_pid (inferior_ptid
),
237 (PTRACE_TYPE_ARG3
) xstateregs
, x86bsd_xsave_len
) == -1)
238 perror_with_name (_("Couldn't write extended state status"));
243 #ifdef HAVE_PT_GETXMMREGS
244 if (have_ptrace_xmmregs
!= 0
245 && ptrace(PT_GETXMMREGS
, get_ptrace_pid (inferior_ptid
),
246 (PTRACE_TYPE_ARG3
) xmmregs
, 0) == 0)
248 have_ptrace_xmmregs
= 1;
250 i387_collect_fxsave (regcache
, regnum
, xmmregs
);
252 if (ptrace (PT_SETXMMREGS
, get_ptrace_pid (inferior_ptid
),
253 (PTRACE_TYPE_ARG3
) xmmregs
, 0) == -1)
254 perror_with_name (_("Couldn't write XMM registers"));
258 have_ptrace_xmmregs
= 0;
260 if (ptrace (PT_GETFPREGS
, get_ptrace_pid (inferior_ptid
),
261 (PTRACE_TYPE_ARG3
) &fpregs
, 0) == -1)
262 perror_with_name (_("Couldn't get floating point status"));
264 i387_collect_fsave (regcache
, regnum
, &fpregs
);
266 if (ptrace (PT_SETFPREGS
, get_ptrace_pid (inferior_ptid
),
267 (PTRACE_TYPE_ARG3
) &fpregs
, 0) == -1)
268 perror_with_name (_("Couldn't write floating point status"));
269 #ifdef HAVE_PT_GETXMMREGS
275 /* Create a prototype *BSD/i386 target. The client can override it
276 with local methods. */
279 i386bsd_target (void)
281 struct target_ops
*t
;
283 t
= x86bsd_target ();
284 t
->to_fetch_registers
= i386bsd_fetch_inferior_registers
;
285 t
->to_store_registers
= i386bsd_store_inferior_registers
;
290 /* Provide a prototype to silence -Wmissing-prototypes. */
291 void _initialize_i386bsd_nat (void);
294 _initialize_i386bsd_nat (void)
298 /* To support the recognition of signal handlers, i386bsd-tdep.c
299 hardcodes some constants. Inclusion of this file means that we
300 are compiling a native debugger, which means that we can use the
301 system header files and sysctl(3) to get at the relevant
304 #if defined (__FreeBSD_version) && __FreeBSD_version >= 400011
305 #define SC_REG_OFFSET i386fbsd4_sc_reg_offset
306 #elif defined (__FreeBSD_version) && __FreeBSD_version >= 300005
307 #define SC_REG_OFFSET i386fbsd_sc_reg_offset
308 #elif defined (NetBSD) || defined (__NetBSD_Version__)
309 #define SC_REG_OFFSET i386nbsd_sc_reg_offset
310 #elif defined (OpenBSD)
311 #define SC_REG_OFFSET i386obsd_sc_reg_offset
316 /* We only check the program counter, stack pointer and frame
317 pointer since these members of `struct sigcontext' are essential
318 for providing backtraces. More checks could be added, but would
319 involve adding configure checks for the appropriate structure
320 members, since older BSD's don't provide all of them. */
322 #define SC_PC_OFFSET SC_REG_OFFSET[I386_EIP_REGNUM]
323 #define SC_SP_OFFSET SC_REG_OFFSET[I386_ESP_REGNUM]
324 #define SC_FP_OFFSET SC_REG_OFFSET[I386_EBP_REGNUM]
326 /* Override the default value for the offset of the program counter
327 in the sigcontext structure. */
328 offset
= offsetof (struct sigcontext
, sc_pc
);
330 if (SC_PC_OFFSET
!= offset
)
333 offsetof (struct sigcontext, sc_pc) yields %d instead of %d.\n\
334 Please report this to <bug-gdb@gnu.org>."),
335 offset
, SC_PC_OFFSET
);
338 SC_PC_OFFSET
= offset
;
340 /* Likewise for the stack pointer. */
341 offset
= offsetof (struct sigcontext
, sc_sp
);
343 if (SC_SP_OFFSET
!= offset
)
346 offsetof (struct sigcontext, sc_sp) yields %d instead of %d.\n\
347 Please report this to <bug-gdb@gnu.org>."),
348 offset
, SC_SP_OFFSET
);
351 SC_SP_OFFSET
= offset
;
353 /* And the frame pointer. */
354 offset
= offsetof (struct sigcontext
, sc_fp
);
356 if (SC_FP_OFFSET
!= offset
)
359 offsetof (struct sigcontext, sc_fp) yields %d instead of %d.\n\
360 Please report this to <bug-gdb@gnu.org>."),
361 offset
, SC_FP_OFFSET
);
364 SC_FP_OFFSET
= offset
;
366 #endif /* SC_REG_OFFSET */