1 /* Native-dependent code for modern i386 BSD's.
3 Copyright (C) 2000-2014 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;
86 /* Supply the general-purpose registers in GREGS, to REGCACHE. */
89 i386bsd_supply_gregset (struct regcache
*regcache
, const void *gregs
)
91 const char *regs
= gregs
;
94 for (regnum
= 0; regnum
< ARRAY_SIZE (i386bsd_r_reg_offset
); regnum
++)
96 int offset
= i386bsd_r_reg_offset
[regnum
];
99 regcache_raw_supply (regcache
, regnum
, regs
+ offset
);
103 /* Collect register REGNUM from REGCACHE and store its contents in
104 GREGS. If REGNUM is -1, collect and store all appropriate
108 i386bsd_collect_gregset (const struct regcache
*regcache
,
109 void *gregs
, int regnum
)
114 for (i
= 0; i
< ARRAY_SIZE (i386bsd_r_reg_offset
); i
++)
116 if (regnum
== -1 || regnum
== i
)
118 int offset
= i386bsd_r_reg_offset
[i
];
121 regcache_raw_collect (regcache
, i
, regs
+ offset
);
126 /* Fetch register REGNUM from the inferior. If REGNUM is -1, do this
127 for all registers (including the floating point registers). */
130 i386bsd_fetch_inferior_registers (struct target_ops
*ops
,
131 struct regcache
*regcache
, int regnum
)
133 if (regnum
== -1 || GETREGS_SUPPLIES (regnum
))
137 if (ptrace (PT_GETREGS
, ptid_get_pid (inferior_ptid
),
138 (PTRACE_TYPE_ARG3
) ®s
, 0) == -1)
139 perror_with_name (_("Couldn't get registers"));
141 i386bsd_supply_gregset (regcache
, ®s
);
146 if (regnum
== -1 || regnum
>= I386_ST0_REGNUM
)
149 #ifdef HAVE_PT_GETXMMREGS
152 if (have_ptrace_xmmregs
!= 0
153 && ptrace(PT_GETXMMREGS
, ptid_get_pid (inferior_ptid
),
154 (PTRACE_TYPE_ARG3
) xmmregs
, 0) == 0)
156 have_ptrace_xmmregs
= 1;
157 i387_supply_fxsave (regcache
, -1, xmmregs
);
161 if (ptrace (PT_GETFPREGS
, ptid_get_pid (inferior_ptid
),
162 (PTRACE_TYPE_ARG3
) &fpregs
, 0) == -1)
163 perror_with_name (_("Couldn't get floating point status"));
165 i387_supply_fsave (regcache
, -1, &fpregs
);
168 if (ptrace (PT_GETFPREGS
, ptid_get_pid (inferior_ptid
),
169 (PTRACE_TYPE_ARG3
) &fpregs
, 0) == -1)
170 perror_with_name (_("Couldn't get floating point status"));
172 i387_supply_fsave (regcache
, -1, &fpregs
);
177 /* Store register REGNUM back into the inferior. If REGNUM is -1, do
178 this for all registers (including the floating point registers). */
181 i386bsd_store_inferior_registers (struct target_ops
*ops
,
182 struct regcache
*regcache
, int regnum
)
184 if (regnum
== -1 || GETREGS_SUPPLIES (regnum
))
188 if (ptrace (PT_GETREGS
, ptid_get_pid (inferior_ptid
),
189 (PTRACE_TYPE_ARG3
) ®s
, 0) == -1)
190 perror_with_name (_("Couldn't get registers"));
192 i386bsd_collect_gregset (regcache
, ®s
, regnum
);
194 if (ptrace (PT_SETREGS
, ptid_get_pid (inferior_ptid
),
195 (PTRACE_TYPE_ARG3
) ®s
, 0) == -1)
196 perror_with_name (_("Couldn't write registers"));
202 if (regnum
== -1 || regnum
>= I386_ST0_REGNUM
)
205 #ifdef HAVE_PT_GETXMMREGS
208 if (have_ptrace_xmmregs
!= 0
209 && ptrace(PT_GETXMMREGS
, ptid_get_pid (inferior_ptid
),
210 (PTRACE_TYPE_ARG3
) xmmregs
, 0) == 0)
212 have_ptrace_xmmregs
= 1;
214 i387_collect_fxsave (regcache
, regnum
, xmmregs
);
216 if (ptrace (PT_SETXMMREGS
, ptid_get_pid (inferior_ptid
),
217 (PTRACE_TYPE_ARG3
) xmmregs
, 0) == -1)
218 perror_with_name (_("Couldn't write XMM registers"));
222 have_ptrace_xmmregs
= 0;
224 if (ptrace (PT_GETFPREGS
, ptid_get_pid (inferior_ptid
),
225 (PTRACE_TYPE_ARG3
) &fpregs
, 0) == -1)
226 perror_with_name (_("Couldn't get floating point status"));
228 i387_collect_fsave (regcache
, regnum
, &fpregs
);
230 if (ptrace (PT_SETFPREGS
, ptid_get_pid (inferior_ptid
),
231 (PTRACE_TYPE_ARG3
) &fpregs
, 0) == -1)
232 perror_with_name (_("Couldn't write floating point status"));
233 #ifdef HAVE_PT_GETXMMREGS
239 /* Create a prototype *BSD/i386 target. The client can override it
240 with local methods. */
243 i386bsd_target (void)
245 struct target_ops
*t
;
247 t
= inf_ptrace_target ();
248 t
->to_fetch_registers
= i386bsd_fetch_inferior_registers
;
249 t
->to_store_registers
= i386bsd_store_inferior_registers
;
254 /* Support for debug registers. */
256 #ifdef HAVE_PT_GETDBREGS
258 /* Not all versions of FreeBSD/i386 that support the debug registers
261 #define DBREG_DRX(d, x) ((&d->dr0)[x])
265 i386bsd_dr_get (ptid_t ptid
, int regnum
)
269 if (ptrace (PT_GETDBREGS
, ptid_get_pid (inferior_ptid
),
270 (PTRACE_TYPE_ARG3
) &dbregs
, 0) == -1)
271 perror_with_name (_("Couldn't read debug registers"));
273 return DBREG_DRX ((&dbregs
), regnum
);
277 i386bsd_dr_set (int regnum
, unsigned int value
)
281 if (ptrace (PT_GETDBREGS
, ptid_get_pid (inferior_ptid
),
282 (PTRACE_TYPE_ARG3
) &dbregs
, 0) == -1)
283 perror_with_name (_("Couldn't get debug registers"));
285 /* For some mysterious reason, some of the reserved bits in the
286 debug control register get set. Mask these off, otherwise the
287 ptrace call below will fail. */
288 DBREG_DRX ((&dbregs
), 7) &= ~(0x0000fc00);
290 DBREG_DRX ((&dbregs
), regnum
) = value
;
292 if (ptrace (PT_SETDBREGS
, ptid_get_pid (inferior_ptid
),
293 (PTRACE_TYPE_ARG3
) &dbregs
, 0) == -1)
294 perror_with_name (_("Couldn't write debug registers"));
298 i386bsd_dr_set_control (unsigned long control
)
300 i386bsd_dr_set (7, control
);
304 i386bsd_dr_set_addr (int regnum
, CORE_ADDR addr
)
306 gdb_assert (regnum
>= 0 && regnum
<= 4);
308 i386bsd_dr_set (regnum
, addr
);
312 i386bsd_dr_get_addr (int regnum
)
314 return i386bsd_dr_get (inferior_ptid
, regnum
);
318 i386bsd_dr_get_status (void)
320 return i386bsd_dr_get (inferior_ptid
, 6);
324 i386bsd_dr_get_control (void)
326 return i386bsd_dr_get (inferior_ptid
, 7);
329 #endif /* PT_GETDBREGS */
332 /* Provide a prototype to silence -Wmissing-prototypes. */
333 void _initialize_i386bsd_nat (void);
336 _initialize_i386bsd_nat (void)
340 /* To support the recognition of signal handlers, i386bsd-tdep.c
341 hardcodes some constants. Inclusion of this file means that we
342 are compiling a native debugger, which means that we can use the
343 system header files and sysctl(3) to get at the relevant
346 #if defined (__FreeBSD_version) && __FreeBSD_version >= 400011
347 #define SC_REG_OFFSET i386fbsd4_sc_reg_offset
348 #elif defined (__FreeBSD_version) && __FreeBSD_version >= 300005
349 #define SC_REG_OFFSET i386fbsd_sc_reg_offset
350 #elif defined (NetBSD) || defined (__NetBSD_Version__)
351 #define SC_REG_OFFSET i386nbsd_sc_reg_offset
352 #elif defined (OpenBSD)
353 #define SC_REG_OFFSET i386obsd_sc_reg_offset
358 /* We only check the program counter, stack pointer and frame
359 pointer since these members of `struct sigcontext' are essential
360 for providing backtraces. More checks could be added, but would
361 involve adding configure checks for the appropriate structure
362 members, since older BSD's don't provide all of them. */
364 #define SC_PC_OFFSET SC_REG_OFFSET[I386_EIP_REGNUM]
365 #define SC_SP_OFFSET SC_REG_OFFSET[I386_ESP_REGNUM]
366 #define SC_FP_OFFSET SC_REG_OFFSET[I386_EBP_REGNUM]
368 /* Override the default value for the offset of the program counter
369 in the sigcontext structure. */
370 offset
= offsetof (struct sigcontext
, sc_pc
);
372 if (SC_PC_OFFSET
!= offset
)
375 offsetof (struct sigcontext, sc_pc) yields %d instead of %d.\n\
376 Please report this to <bug-gdb@gnu.org>."),
377 offset
, SC_PC_OFFSET
);
380 SC_PC_OFFSET
= offset
;
382 /* Likewise for the stack pointer. */
383 offset
= offsetof (struct sigcontext
, sc_sp
);
385 if (SC_SP_OFFSET
!= offset
)
388 offsetof (struct sigcontext, sc_sp) yields %d instead of %d.\n\
389 Please report this to <bug-gdb@gnu.org>."),
390 offset
, SC_SP_OFFSET
);
393 SC_SP_OFFSET
= offset
;
395 /* And the frame pointer. */
396 offset
= offsetof (struct sigcontext
, sc_fp
);
398 if (SC_FP_OFFSET
!= offset
)
401 offsetof (struct sigcontext, sc_fp) yields %d instead of %d.\n\
402 Please report this to <bug-gdb@gnu.org>."),
403 offset
, SC_FP_OFFSET
);
406 SC_FP_OFFSET
= offset
;
408 #endif /* SC_REG_OFFSET */