1 /* Native-dependent code for modern i386 BSD's.
3 Copyright (C) 2000-2015 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 "i386bsd-nat.h"
33 #include "inf-ptrace.h"
36 /* In older BSD versions we cannot get at some of the segment
37 registers. FreeBSD for example didn't support the %fs and %gs
38 registers until the 3.0 release. We have autoconf checks for their
39 presence, and deal gracefully with their absence. */
41 /* Offset in `struct reg' where MEMBER is stored. */
42 #define REG_OFFSET(member) offsetof (struct reg, member)
44 /* At i386bsd_reg_offset[REGNUM] you'll find the offset in `struct
45 reg' where the GDB register REGNUM is stored. Unsupported
46 registers are marked with `-1'. */
47 static int i386bsd_r_reg_offset
[] =
58 REG_OFFSET (r_eflags
),
63 #ifdef HAVE_STRUCT_REG_R_FS
68 #ifdef HAVE_STRUCT_REG_R_GS
75 /* Macro to determine if a register is fetched with PT_GETREGS. */
76 #define GETREGS_SUPPLIES(regnum) \
77 ((0 <= (regnum) && (regnum) <= 15))
79 #ifdef HAVE_PT_GETXMMREGS
80 /* Set to 1 if the kernel supports PT_GETXMMREGS. Initialized to -1
81 so that we try PT_GETXMMREGS the first time around. */
82 static int have_ptrace_xmmregs
= -1;
85 #ifdef PT_GETXSTATE_INFO
86 size_t i386bsd_xsave_len
;
90 /* Supply the general-purpose registers in GREGS, to REGCACHE. */
93 i386bsd_supply_gregset (struct regcache
*regcache
, const void *gregs
)
95 const char *regs
= gregs
;
98 for (regnum
= 0; regnum
< ARRAY_SIZE (i386bsd_r_reg_offset
); regnum
++)
100 int offset
= i386bsd_r_reg_offset
[regnum
];
103 regcache_raw_supply (regcache
, regnum
, regs
+ offset
);
107 /* Collect register REGNUM from REGCACHE and store its contents in
108 GREGS. If REGNUM is -1, collect and store all appropriate
112 i386bsd_collect_gregset (const struct regcache
*regcache
,
113 void *gregs
, int regnum
)
118 for (i
= 0; i
< ARRAY_SIZE (i386bsd_r_reg_offset
); i
++)
120 if (regnum
== -1 || regnum
== i
)
122 int offset
= i386bsd_r_reg_offset
[i
];
125 regcache_raw_collect (regcache
, i
, regs
+ offset
);
130 /* Fetch register REGNUM from the inferior. If REGNUM is -1, do this
131 for all registers (including the floating point registers). */
134 i386bsd_fetch_inferior_registers (struct target_ops
*ops
,
135 struct regcache
*regcache
, int regnum
)
137 if (regnum
== -1 || GETREGS_SUPPLIES (regnum
))
141 if (ptrace (PT_GETREGS
, ptid_get_pid (inferior_ptid
),
142 (PTRACE_TYPE_ARG3
) ®s
, 0) == -1)
143 perror_with_name (_("Couldn't get registers"));
145 i386bsd_supply_gregset (regcache
, ®s
);
150 if (regnum
== -1 || regnum
>= I386_ST0_REGNUM
)
153 #ifdef HAVE_PT_GETXMMREGS
157 #ifdef PT_GETXSTATE_INFO
158 if (i386bsd_xsave_len
!= 0)
162 xstateregs
= alloca (i386bsd_xsave_len
);
163 if (ptrace (PT_GETXSTATE
, ptid_get_pid (inferior_ptid
),
164 (PTRACE_TYPE_ARG3
) xstateregs
, 0) == -1)
165 perror_with_name (_("Couldn't get extended state status"));
167 i387_supply_xsave (regcache
, -1, xstateregs
);
172 #ifdef HAVE_PT_GETXMMREGS
173 if (have_ptrace_xmmregs
!= 0
174 && ptrace(PT_GETXMMREGS
, ptid_get_pid (inferior_ptid
),
175 (PTRACE_TYPE_ARG3
) xmmregs
, 0) == 0)
177 have_ptrace_xmmregs
= 1;
178 i387_supply_fxsave (regcache
, -1, xmmregs
);
182 have_ptrace_xmmregs
= 0;
184 if (ptrace (PT_GETFPREGS
, ptid_get_pid (inferior_ptid
),
185 (PTRACE_TYPE_ARG3
) &fpregs
, 0) == -1)
186 perror_with_name (_("Couldn't get floating point status"));
188 i387_supply_fsave (regcache
, -1, &fpregs
);
189 #ifdef HAVE_PT_GETXMMREGS
195 /* Store register REGNUM back into the inferior. If REGNUM is -1, do
196 this for all registers (including the floating point registers). */
199 i386bsd_store_inferior_registers (struct target_ops
*ops
,
200 struct regcache
*regcache
, int regnum
)
202 if (regnum
== -1 || GETREGS_SUPPLIES (regnum
))
206 if (ptrace (PT_GETREGS
, ptid_get_pid (inferior_ptid
),
207 (PTRACE_TYPE_ARG3
) ®s
, 0) == -1)
208 perror_with_name (_("Couldn't get registers"));
210 i386bsd_collect_gregset (regcache
, ®s
, regnum
);
212 if (ptrace (PT_SETREGS
, ptid_get_pid (inferior_ptid
),
213 (PTRACE_TYPE_ARG3
) ®s
, 0) == -1)
214 perror_with_name (_("Couldn't write registers"));
220 if (regnum
== -1 || regnum
>= I386_ST0_REGNUM
)
223 #ifdef HAVE_PT_GETXMMREGS
227 #ifdef PT_GETXSTATE_INFO
228 if (i386bsd_xsave_len
!= 0)
232 xstateregs
= alloca (i386bsd_xsave_len
);
233 if (ptrace (PT_GETXSTATE
, ptid_get_pid (inferior_ptid
),
234 (PTRACE_TYPE_ARG3
) xstateregs
, 0) == -1)
235 perror_with_name (_("Couldn't get extended state status"));
237 i387_collect_xsave (regcache
, -1, xstateregs
, 0);
239 if (ptrace (PT_SETXSTATE
, ptid_get_pid (inferior_ptid
),
240 (PTRACE_TYPE_ARG3
) xstateregs
, i386bsd_xsave_len
) == -1)
241 perror_with_name (_("Couldn't write extended state status"));
246 #ifdef HAVE_PT_GETXMMREGS
247 if (have_ptrace_xmmregs
!= 0
248 && ptrace(PT_GETXMMREGS
, ptid_get_pid (inferior_ptid
),
249 (PTRACE_TYPE_ARG3
) xmmregs
, 0) == 0)
251 have_ptrace_xmmregs
= 1;
253 i387_collect_fxsave (regcache
, regnum
, xmmregs
);
255 if (ptrace (PT_SETXMMREGS
, ptid_get_pid (inferior_ptid
),
256 (PTRACE_TYPE_ARG3
) xmmregs
, 0) == -1)
257 perror_with_name (_("Couldn't write XMM registers"));
261 have_ptrace_xmmregs
= 0;
263 if (ptrace (PT_GETFPREGS
, ptid_get_pid (inferior_ptid
),
264 (PTRACE_TYPE_ARG3
) &fpregs
, 0) == -1)
265 perror_with_name (_("Couldn't get floating point status"));
267 i387_collect_fsave (regcache
, regnum
, &fpregs
);
269 if (ptrace (PT_SETFPREGS
, ptid_get_pid (inferior_ptid
),
270 (PTRACE_TYPE_ARG3
) &fpregs
, 0) == -1)
271 perror_with_name (_("Couldn't write floating point status"));
272 #ifdef HAVE_PT_GETXMMREGS
278 /* Create a prototype *BSD/i386 target. The client can override it
279 with local methods. */
282 i386bsd_target (void)
284 struct target_ops
*t
;
286 t
= inf_ptrace_target ();
287 t
->to_fetch_registers
= i386bsd_fetch_inferior_registers
;
288 t
->to_store_registers
= i386bsd_store_inferior_registers
;
293 /* Support for debug registers. */
295 #ifdef HAVE_PT_GETDBREGS
297 /* Not all versions of FreeBSD/i386 that support the debug registers
300 #define DBREG_DRX(d, x) ((&d->dr0)[x])
304 i386bsd_dr_get (ptid_t ptid
, int regnum
)
308 if (ptrace (PT_GETDBREGS
, ptid_get_pid (inferior_ptid
),
309 (PTRACE_TYPE_ARG3
) &dbregs
, 0) == -1)
310 perror_with_name (_("Couldn't read debug registers"));
312 return DBREG_DRX ((&dbregs
), regnum
);
316 i386bsd_dr_set (int regnum
, unsigned int value
)
320 if (ptrace (PT_GETDBREGS
, ptid_get_pid (inferior_ptid
),
321 (PTRACE_TYPE_ARG3
) &dbregs
, 0) == -1)
322 perror_with_name (_("Couldn't get debug registers"));
324 /* For some mysterious reason, some of the reserved bits in the
325 debug control register get set. Mask these off, otherwise the
326 ptrace call below will fail. */
327 DBREG_DRX ((&dbregs
), 7) &= ~(0x0000fc00);
329 DBREG_DRX ((&dbregs
), regnum
) = value
;
331 if (ptrace (PT_SETDBREGS
, ptid_get_pid (inferior_ptid
),
332 (PTRACE_TYPE_ARG3
) &dbregs
, 0) == -1)
333 perror_with_name (_("Couldn't write debug registers"));
337 i386bsd_dr_set_control (unsigned long control
)
339 i386bsd_dr_set (7, control
);
343 i386bsd_dr_set_addr (int regnum
, CORE_ADDR addr
)
345 gdb_assert (regnum
>= 0 && regnum
<= 4);
347 i386bsd_dr_set (regnum
, addr
);
351 i386bsd_dr_get_addr (int regnum
)
353 return i386bsd_dr_get (inferior_ptid
, regnum
);
357 i386bsd_dr_get_status (void)
359 return i386bsd_dr_get (inferior_ptid
, 6);
363 i386bsd_dr_get_control (void)
365 return i386bsd_dr_get (inferior_ptid
, 7);
368 #endif /* PT_GETDBREGS */
371 /* Provide a prototype to silence -Wmissing-prototypes. */
372 void _initialize_i386bsd_nat (void);
375 _initialize_i386bsd_nat (void)
379 /* To support the recognition of signal handlers, i386bsd-tdep.c
380 hardcodes some constants. Inclusion of this file means that we
381 are compiling a native debugger, which means that we can use the
382 system header files and sysctl(3) to get at the relevant
385 #if defined (__FreeBSD_version) && __FreeBSD_version >= 400011
386 #define SC_REG_OFFSET i386fbsd4_sc_reg_offset
387 #elif defined (__FreeBSD_version) && __FreeBSD_version >= 300005
388 #define SC_REG_OFFSET i386fbsd_sc_reg_offset
389 #elif defined (NetBSD) || defined (__NetBSD_Version__)
390 #define SC_REG_OFFSET i386nbsd_sc_reg_offset
391 #elif defined (OpenBSD)
392 #define SC_REG_OFFSET i386obsd_sc_reg_offset
397 /* We only check the program counter, stack pointer and frame
398 pointer since these members of `struct sigcontext' are essential
399 for providing backtraces. More checks could be added, but would
400 involve adding configure checks for the appropriate structure
401 members, since older BSD's don't provide all of them. */
403 #define SC_PC_OFFSET SC_REG_OFFSET[I386_EIP_REGNUM]
404 #define SC_SP_OFFSET SC_REG_OFFSET[I386_ESP_REGNUM]
405 #define SC_FP_OFFSET SC_REG_OFFSET[I386_EBP_REGNUM]
407 /* Override the default value for the offset of the program counter
408 in the sigcontext structure. */
409 offset
= offsetof (struct sigcontext
, sc_pc
);
411 if (SC_PC_OFFSET
!= offset
)
414 offsetof (struct sigcontext, sc_pc) yields %d instead of %d.\n\
415 Please report this to <bug-gdb@gnu.org>."),
416 offset
, SC_PC_OFFSET
);
419 SC_PC_OFFSET
= offset
;
421 /* Likewise for the stack pointer. */
422 offset
= offsetof (struct sigcontext
, sc_sp
);
424 if (SC_SP_OFFSET
!= offset
)
427 offsetof (struct sigcontext, sc_sp) yields %d instead of %d.\n\
428 Please report this to <bug-gdb@gnu.org>."),
429 offset
, SC_SP_OFFSET
);
432 SC_SP_OFFSET
= offset
;
434 /* And the frame pointer. */
435 offset
= offsetof (struct sigcontext
, sc_fp
);
437 if (SC_FP_OFFSET
!= offset
)
440 offsetof (struct sigcontext, sc_fp) yields %d instead of %d.\n\
441 Please report this to <bug-gdb@gnu.org>."),
442 offset
, SC_FP_OFFSET
);
445 SC_FP_OFFSET
= offset
;
447 #endif /* SC_REG_OFFSET */