1 /* Native-dependent code for modern i386 BSD's.
3 Copyright 2000, 2001, 2002, 2003, 2004 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 2 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, write to the Free Software
19 Foundation, Inc., 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
26 #include "gdb_assert.h"
29 #include <sys/types.h>
30 #include <sys/ptrace.h>
31 #include <machine/reg.h>
32 #include <machine/frame.h>
34 #include "i386-tdep.h"
35 #include "i387-tdep.h"
36 #include "i386bsd-nat.h"
37 #include "inf-ptrace.h"
40 /* In older BSD versions we cannot get at some of the segment
41 registers. FreeBSD for example didn't support the %fs and %gs
42 registers until the 3.0 release. We have autoconf checks for their
43 presence, and deal gracefully with their absence. */
45 /* Offset in `struct reg' where MEMBER is stored. */
46 #define REG_OFFSET(member) offsetof (struct reg, member)
48 /* At i386bsd_reg_offset[REGNUM] you'll find the offset in `struct
49 reg' where the GDB register REGNUM is stored. Unsupported
50 registers are marked with `-1'. */
51 static int i386bsd_r_reg_offset
[] =
62 REG_OFFSET (r_eflags
),
67 #ifdef HAVE_STRUCT_REG_R_FS
72 #ifdef HAVE_STRUCT_REG_R_GS
79 /* Macro to determine if a register is fetched with PT_GETREGS. */
80 #define GETREGS_SUPPLIES(regnum) \
81 ((0 <= (regnum) && (regnum) <= 15))
83 #ifdef HAVE_PT_GETXMMREGS
84 /* Set to 1 if the kernel supports PT_GETXMMREGS. Initialized to -1
85 so that we try PT_GETXMMREGS the first time around. */
86 static int have_ptrace_xmmregs
= -1;
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 (int regnum
)
136 if (regnum
== -1 || GETREGS_SUPPLIES (regnum
))
140 if (ptrace (PT_GETREGS
, PIDGET (inferior_ptid
),
141 (PTRACE_TYPE_ARG3
) ®s
, 0) == -1)
142 perror_with_name ("Couldn't get registers");
144 i386bsd_supply_gregset (current_regcache
, ®s
);
149 if (regnum
== -1 || regnum
>= I386_ST0_REGNUM
)
152 #ifdef HAVE_PT_GETXMMREGS
155 if (have_ptrace_xmmregs
!= 0
156 && ptrace(PT_GETXMMREGS
, PIDGET (inferior_ptid
),
157 (PTRACE_TYPE_ARG3
) xmmregs
, 0) == 0)
159 have_ptrace_xmmregs
= 1;
160 i387_supply_fxsave (current_regcache
, -1, xmmregs
);
164 if (ptrace (PT_GETFPREGS
, PIDGET (inferior_ptid
),
165 (PTRACE_TYPE_ARG3
) &fpregs
, 0) == -1)
166 perror_with_name ("Couldn't get floating point status");
168 i387_supply_fsave (current_regcache
, -1, &fpregs
);
171 if (ptrace (PT_GETFPREGS
, PIDGET (inferior_ptid
),
172 (PTRACE_TYPE_ARG3
) &fpregs
, 0) == -1)
173 perror_with_name ("Couldn't get floating point status");
175 i387_supply_fsave (current_regcache
, -1, &fpregs
);
180 /* Store register REGNUM back into the inferior. If REGNUM is -1, do
181 this for all registers (including the floating point registers). */
184 i386bsd_store_inferior_registers (int regnum
)
186 if (regnum
== -1 || GETREGS_SUPPLIES (regnum
))
190 if (ptrace (PT_GETREGS
, PIDGET (inferior_ptid
),
191 (PTRACE_TYPE_ARG3
) ®s
, 0) == -1)
192 perror_with_name ("Couldn't get registers");
194 i386bsd_collect_gregset (current_regcache
, ®s
, regnum
);
196 if (ptrace (PT_SETREGS
, PIDGET (inferior_ptid
),
197 (PTRACE_TYPE_ARG3
) ®s
, 0) == -1)
198 perror_with_name ("Couldn't write registers");
204 if (regnum
== -1 || regnum
>= I386_ST0_REGNUM
)
207 #ifdef HAVE_PT_GETXMMREGS
210 if (have_ptrace_xmmregs
!= 0
211 && ptrace(PT_GETXMMREGS
, PIDGET (inferior_ptid
),
212 (PTRACE_TYPE_ARG3
) xmmregs
, 0) == 0)
214 have_ptrace_xmmregs
= 1;
216 i387_collect_fxsave (current_regcache
, regnum
, xmmregs
);
218 if (ptrace (PT_SETXMMREGS
, PIDGET (inferior_ptid
),
219 (PTRACE_TYPE_ARG3
) xmmregs
, 0) == -1)
220 perror_with_name ("Couldn't write XMM registers");
224 have_ptrace_xmmregs
= 0;
226 if (ptrace (PT_GETFPREGS
, PIDGET (inferior_ptid
),
227 (PTRACE_TYPE_ARG3
) &fpregs
, 0) == -1)
228 perror_with_name ("Couldn't get floating point status");
230 i387_collect_fsave (current_regcache
, regnum
, &fpregs
);
232 if (ptrace (PT_SETFPREGS
, PIDGET (inferior_ptid
),
233 (PTRACE_TYPE_ARG3
) &fpregs
, 0) == -1)
234 perror_with_name ("Couldn't write floating point status");
235 #ifdef HAVE_PT_GETXMMREGS
241 /* Create a prototype *BSD/i386 target. The client can override it
242 with local methods. */
245 i386bsd_target (void)
247 struct target_ops
*t
;
249 t
= inf_ptrace_target ();
250 t
->to_fetch_registers
= i386bsd_fetch_inferior_registers
;
251 t
->to_store_registers
= i386bsd_store_inferior_registers
;
256 /* Support for debug registers. */
258 #ifdef HAVE_PT_GETDBREGS
260 /* Not all versions of FreeBSD/i386 that support the debug registers
263 #define DBREG_DRX(d, x) ((&d->dr0)[x])
267 i386bsd_dr_set (int regnum
, unsigned int value
)
271 if (ptrace (PT_GETDBREGS
, PIDGET (inferior_ptid
),
272 (PTRACE_TYPE_ARG3
) &dbregs
, 0) == -1)
273 perror_with_name ("Couldn't get debug registers");
275 /* For some mysterious reason, some of the reserved bits in the
276 debug control register get set. Mask these off, otherwise the
277 ptrace call below will fail. */
278 DBREG_DRX ((&dbregs
), 7) &= ~(0x0000fc00);
280 DBREG_DRX ((&dbregs
), regnum
) = value
;
282 if (ptrace (PT_SETDBREGS
, PIDGET (inferior_ptid
),
283 (PTRACE_TYPE_ARG3
) &dbregs
, 0) == -1)
284 perror_with_name ("Couldn't write debug registers");
288 i386bsd_dr_set_control (unsigned long control
)
290 i386bsd_dr_set (7, control
);
294 i386bsd_dr_set_addr (int regnum
, CORE_ADDR addr
)
296 gdb_assert (regnum
>= 0 && regnum
<= 4);
298 i386bsd_dr_set (regnum
, addr
);
302 i386bsd_dr_reset_addr (int regnum
)
304 gdb_assert (regnum
>= 0 && regnum
<= 4);
306 i386bsd_dr_set (regnum
, 0);
310 i386bsd_dr_get_status (void)
314 /* FIXME: kettenis/2001-03-31: Calling perror_with_name if the
315 ptrace call fails breaks debugging remote targets. The correct
316 way to fix this is to add the hardware breakpoint and watchpoint
317 stuff to the target vector. For now, just return zero if the
318 ptrace call fails. */
319 if (ptrace (PT_GETDBREGS
, PIDGET (inferior_ptid
),
320 (PTRACE_TYPE_ARG3
) &dbregs
, 0) == -1)
322 perror_with_name ("Couldn't read debug registers");
327 return DBREG_DRX ((&dbregs
), 6);
330 #endif /* PT_GETDBREGS */
333 /* Support for the user struct. */
335 /* Return the address register REGNUM. BLOCKEND is the value of
336 u.u_ar0, which should point to the registers. */
339 register_u_addr (CORE_ADDR blockend
, int regnum
)
341 gdb_assert (regnum
>= 0 && regnum
< ARRAY_SIZE (i386bsd_r_reg_offset
));
343 return blockend
+ i386bsd_r_reg_offset
[regnum
];
346 #include <sys/param.h>
347 #include <sys/user.h>
349 /* Return the size of the user struct. */
354 return (sizeof (struct user
));
358 _initialize_i386bsd_nat (void)
362 /* To support the recognition of signal handlers, i386bsd-tdep.c
363 hardcodes some constants. Inclusion of this file means that we
364 are compiling a native debugger, which means that we can use the
365 system header files and sysctl(3) to get at the relevant
368 #if defined (__FreeBSD_version) && __FreeBSD_version >= 400011
369 #define SC_REG_OFFSET i386fbsd4_sc_reg_offset
370 #elif defined (__FreeBSD_version) && __FreeBSD_version >= 300005
371 #define SC_REG_OFFSET i386fbsd_sc_reg_offset
372 #elif defined (NetBSD) || defined (__NetBSD_Version__)
373 #define SC_REG_OFFSET i386nbsd_sc_reg_offset
374 #elif defined (OpenBSD)
375 #define SC_REG_OFFSET i386obsd_sc_reg_offset
380 /* We only check the program counter, stack pointer and frame
381 pointer since these members of `struct sigcontext' are essential
382 for providing backtraces. More checks could be added, but would
383 involve adding configure checks for the appropriate structure
384 members, since older BSD's don't provide all of them. */
386 #define SC_PC_OFFSET SC_REG_OFFSET[I386_EIP_REGNUM]
387 #define SC_SP_OFFSET SC_REG_OFFSET[I386_ESP_REGNUM]
388 #define SC_FP_OFFSET SC_REG_OFFSET[I386_EBP_REGNUM]
390 /* Override the default value for the offset of the program counter
391 in the sigcontext structure. */
392 offset
= offsetof (struct sigcontext
, sc_pc
);
394 if (SC_PC_OFFSET
!= offset
)
397 offsetof (struct sigcontext, sc_pc) yields %d instead of %d.\n\
398 Please report this to <bug-gdb@gnu.org>.",
399 offset
, SC_PC_OFFSET
);
402 SC_PC_OFFSET
= offset
;
404 /* Likewise for the stack pointer. */
405 offset
= offsetof (struct sigcontext
, sc_sp
);
407 if (SC_SP_OFFSET
!= offset
)
410 offsetof (struct sigcontext, sc_sp) yields %d instead of %d.\n\
411 Please report this to <bug-gdb@gnu.org>.",
412 offset
, SC_SP_OFFSET
);
415 SC_SP_OFFSET
= offset
;
417 /* And the frame pointer. */
418 offset
= offsetof (struct sigcontext
, sc_fp
);
420 if (SC_FP_OFFSET
!= offset
)
423 offsetof (struct sigcontext, sc_fp) yields %d instead of %d.\n\
424 Please report this to <bug-gdb@gnu.org>.",
425 offset
, SC_FP_OFFSET
);
428 SC_FP_OFFSET
= offset
;
430 #endif /* SC_REG_OFFSET */