aboutsummaryrefslogtreecommitdiff
path: root/gdb/lynx-nat.c
blob: 8b2c7c8fa9ac0ca7eb4a9fa400976b2d9536f6b9 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
/* Native-dependent code for LynxOS.
   Copyright 1993 Free Software Foundation, Inc.

This file is part of GDB.

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */

#include "defs.h"
#include "frame.h"
#include "inferior.h"
#include "target.h"

#include <sys/ptrace.h>
#include "/usr/include/sys/wait.h"

static unsigned long registers_addr PARAMS ((int pid));

#define X(ENTRY)(offsetof(struct econtext, ENTRY))

#ifdef I386
/* Mappings from tm-i386v.h */

static int regmap[] =
{
  X(eax),
  X(ecx),
  X(edx),
  X(ebx),
  X(esp),			/* sp */
  X(ebp),			/* fp */
  X(esi),
  X(edi),
  X(eip),			/* pc */
  X(flags),			/* ps */
  X(cs),
  X(ss),
  X(ds),
  X(es),
  X(ecode),			/* Lynx doesn't give us either fs or gs, so */
  X(fault),			/* we just substitute these two in the hopes
				   that they are useful. */
};
#endif

#ifdef M68K
/* Mappings from tm-m68k.h */

static int regmap[] =
{
  X(regs[0]),			/* d0 */
  X(regs[1]),			/* d1 */
  X(regs[2]),			/* d2 */
  X(regs[3]),			/* d3 */
  X(regs[4]),			/* d4 */
  X(regs[5]),			/* d5 */
  X(regs[6]),			/* d6 */
  X(regs[7]),			/* d7 */
  X(regs[8]),			/* a0 */
  X(regs[9]),			/* a1 */
  X(regs[10]),			/* a2 */
  X(regs[11]),			/* a3 */
  X(regs[12]),			/* a4 */
  X(regs[13]),			/* a5 */
  X(regs[14]),			/* fp */
  offsetof (st_t, usp) - offsetof (st_t, ec), /* sp */
  X(status),			/* ps */
  X(pc),

  X(fregs[0*3]),		/* fp0 */
  X(fregs[1*3]),		/* fp1 */
  X(fregs[2*3]),		/* fp2 */
  X(fregs[3*3]),		/* fp3 */
  X(fregs[4*3]),		/* fp4 */
  X(fregs[5*3]),		/* fp5 */
  X(fregs[6*3]),		/* fp6 */
  X(fregs[7*3]),		/* fp7 */

  X(fcregs[0]),			/* fpcontrol */
  X(fcregs[1]),			/* fpstatus */
  X(fcregs[2]),			/* fpiaddr */
  X(ssw),			/* fpcode */
  X(fault),			/* fpflags */
};
#endif

/* Return the offset relative to the start of the per-thread data to the
   saved context block.  */

static unsigned long
registers_addr(pid)
     int pid;
{
  CORE_ADDR stblock;
  int ecpoff = offsetof(st_t, ecp);
  CORE_ADDR ecp;

  errno = 0;
  stblock = (CORE_ADDR) ptrace (PTRACE_THREADUSER, pid, (PTRACE_ARG3_TYPE)0,
				0);
  if (errno)
    perror_with_name ("registers_addr(PTRACE_THREADUSER)");

  ecp = (CORE_ADDR) ptrace (PTRACE_PEEKTHREAD, pid, (PTRACE_ARG3_TYPE)ecpoff,
			    0);
  if (errno)
    perror_with_name ("registers_addr(PTRACE_PEEKTHREAD)");

  return ecp - stblock;
}

/* Fetch one or more registers from the inferior.  REGNO == -1 to get
   them all.  We actually fetch more than requested, when convenient,
   marking them as valid so we won't fetch them again.  */

void
fetch_inferior_registers (regno)
     int regno;
{
  int reglo, reghi;
  int i;
  unsigned long ecp;

  if (regno == -1)
    {
      reglo = 0;
      reghi = NUM_REGS - 1;
    }
  else
    reglo = reghi = regno;

  ecp = registers_addr (inferior_pid);

  for (regno = reglo; regno <= reghi; regno++)
    {
      char buf[MAX_REGISTER_RAW_SIZE];
      int ptrace_fun = PTRACE_PEEKTHREAD;

#ifdef PTRACE_PEEKUSP
      ptrace_fun = regno == SP_REGNUM ? PTRACE_PEEKUSP : PTRACE_PEEKTHREAD;
#endif

      for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof (int))
	{
	  unsigned int reg;

	  errno = 0;
	  reg = ptrace (ptrace_fun, inferior_pid,
			(PTRACE_ARG3_TYPE) (ecp + regmap[regno] + i), 0);
	  if (errno)
	    perror_with_name ("fetch_inferior_registers(ptrace)");
  
	  *(int *)&buf[i] = reg;
	}
      supply_register (regno, buf);
    }
}

/* Store our register values back into the inferior.
   If REGNO is -1, do this for all registers.
   Otherwise, REGNO specifies which register (so we can save time).  */

void
store_inferior_registers (regno)
     int regno;
{
  int reglo, reghi;
  int i;
  unsigned long ecp;

  if (regno == -1)
    {
      reglo = 0;
      reghi = NUM_REGS - 1;
    }
  else
    reglo = reghi = regno;

  ecp = registers_addr (inferior_pid);

  for (regno = reglo; regno <= reghi; regno++)
    {
      int ptrace_fun = PTRACE_POKEUSER;

#ifdef PTRACE_POKEUSP
      ptrace_fun = regno == SP_REGNUM ? PTRACE_POKEUSP : PTRACE_POKEUSER;
#endif

      for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof (int))
	{
	  unsigned int reg;

	  reg = *(unsigned int *)&registers[REGISTER_BYTE (regno) + i];

	  errno = 0;
	  ptrace (ptrace_fun, inferior_pid,
		  (PTRACE_ARG3_TYPE) (ecp + regmap[regno] + i), reg);
	  if (errno)
	    perror_with_name ("PTRACE_POKEUSER");
	}
    }
}

/* Wait for child to do something.  Return pid of child, or -1 in case
   of error; store status through argument pointer STATUS.  */

int
child_wait (pid, status)
     int pid;
     int *status;
{
  int save_errno;
  int thread;

  while (1)
    {
      int sig;

      if (attach_flag)
	set_sigint_trap();	/* Causes SIGINT to be passed on to the
				   attached process. */
      pid = wait (status);
      save_errno = errno;

      if (attach_flag)
	clear_sigint_trap();

      if (pid == -1)
	{
	  if (save_errno == EINTR)
	    continue;
	  fprintf_unfiltered (gdb_stderr, "Child process unexpectedly missing: %s.\n",
		   safe_strerror (save_errno));
	  *status = 42;		/* Claim it exited with signal 42 */
	  return -1;
	}

      if (pid != PIDGET (inferior_pid))	/* Some other process?!? */
	continue;

/*      thread = WIFTID (*status);*/
      thread = *status >> 16;

      /* Initial thread value can only be acquired via wait, so we have to
	 resort to this hack.  */

      if (TIDGET (inferior_pid) == 0)
	{
	  inferior_pid = BUILDPID (inferior_pid, thread);
	  add_thread (inferior_pid);
	}

      pid = BUILDPID (pid, thread);

      return pid;
    }
}

/* Convert a Lynx process ID to a string.  Returns the string in a static
   buffer.  */

char *
lynx_pid_to_str (pid)
     int pid;
{
  static char buf[40];

  sprintf (buf, "process %d thread %d", PIDGET (pid), TIDGET (pid));

  return buf;
}

/* Extract the register values out of the core file and store
   them where `read_register' will find them.

   CORE_REG_SECT points to the register values themselves, read into memory.
   CORE_REG_SIZE is the size of that area.
   WHICH says which set of registers we are handling (0 = int, 2 = float
         on machines where they are discontiguous).
   REG_ADDR is the offset from u.u_ar0 to the register values relative to
            core_reg_sect.  This is used with old-fashioned core files to
	    locate the registers in a large upage-plus-stack ".reg" section.
	    Original upage address X is at location core_reg_sect+x+reg_addr.
 */

void
fetch_core_registers (core_reg_sect, core_reg_size, which, reg_addr)
     char *core_reg_sect;
     unsigned core_reg_size;
     int which;
     unsigned reg_addr;
{
  struct st_entry s;
  unsigned int regno;

  for (regno = 0; regno < NUM_REGS; regno++)
    supply_register (regno, core_reg_sect + offsetof (st_t, ec)
		     + regmap[regno]);
}