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
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
|
/* Main code for remote server for GDB.
Copyright 1989, 1993, 1994, 1995, 1997, 1998, 1999, 2000, 2002, 2003, 2004,
2005
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., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include "server.h"
#include <unistd.h>
#include <signal.h>
#include <sys/wait.h>
unsigned long cont_thread;
unsigned long general_thread;
unsigned long step_thread;
unsigned long thread_from_wait;
unsigned long old_thread_from_wait;
int extended_protocol;
int server_waiting;
jmp_buf toplevel;
/* The PID of the originally created or attached inferior. Used to
send signals to the process when GDB sends us an asynchronous interrupt
(user hitting Control-C in the client), and to wait for the child to exit
when no longer debugging it. */
unsigned long signal_pid;
static int
start_inferior (char *argv[], char *statusptr)
{
signal (SIGTTOU, SIG_DFL);
signal (SIGTTIN, SIG_DFL);
signal_pid = create_inferior (argv[0], argv);
fprintf (stderr, "Process %s created; pid = %ld\n", argv[0],
signal_pid);
signal (SIGTTOU, SIG_IGN);
signal (SIGTTIN, SIG_IGN);
tcsetpgrp (fileno (stderr), signal_pid);
/* Wait till we are at 1st instruction in program, return signal number. */
return mywait (statusptr, 0);
}
static int
attach_inferior (int pid, char *statusptr, int *sigptr)
{
/* myattach should return -1 if attaching is unsupported,
0 if it succeeded, and call error() otherwise. */
if (myattach (pid) != 0)
return -1;
fprintf (stderr, "Attached; pid = %d\n", pid);
/* FIXME - It may be that we should get the SIGNAL_PID from the
attach function, so that it can be the main thread instead of
whichever we were told to attach to. */
signal_pid = pid;
*sigptr = mywait (statusptr, 0);
return 0;
}
extern int remote_debug;
/* Handle all of the extended 'q' packets. */
void
handle_query (char *own_buf)
{
static struct inferior_list_entry *thread_ptr;
if (strcmp ("qSymbol::", own_buf) == 0)
{
if (the_target->look_up_symbols != NULL)
(*the_target->look_up_symbols) ();
strcpy (own_buf, "OK");
return;
}
if (strcmp ("qfThreadInfo", own_buf) == 0)
{
thread_ptr = all_threads.head;
sprintf (own_buf, "m%lx", thread_ptr->id);
thread_ptr = thread_ptr->next;
return;
}
if (strcmp ("qsThreadInfo", own_buf) == 0)
{
if (thread_ptr != NULL)
{
sprintf (own_buf, "m%lx", thread_ptr->id);
thread_ptr = thread_ptr->next;
return;
}
else
{
sprintf (own_buf, "l");
return;
}
}
if (the_target->read_auxv != NULL
&& strncmp ("qPart:auxv:read::", own_buf, 17) == 0)
{
unsigned char data[(PBUFSIZ - 1) / 2];
CORE_ADDR ofs;
unsigned int len;
int n;
decode_m_packet (&own_buf[17], &ofs, &len); /* "OFS,LEN" */
if (len > sizeof data)
len = sizeof data;
n = (*the_target->read_auxv) (ofs, data, len);
if (n == 0)
write_ok (own_buf);
else if (n < 0)
write_enn (own_buf);
else
convert_int_to_ascii (data, own_buf, n);
return;
}
/* Otherwise we didn't know what packet it was. Say we didn't
understand it. */
own_buf[0] = 0;
}
/* Parse vCont packets. */
void
handle_v_cont (char *own_buf, char *status, int *signal)
{
char *p, *q;
int n = 0, i = 0;
struct thread_resume *resume_info, default_action;
/* Count the number of semicolons in the packet. There should be one
for every action. */
p = &own_buf[5];
while (p)
{
n++;
p++;
p = strchr (p, ';');
}
/* Allocate room for one extra action, for the default remain-stopped
behavior; if no default action is in the list, we'll need the extra
slot. */
resume_info = malloc ((n + 1) * sizeof (resume_info[0]));
default_action.thread = -1;
default_action.leave_stopped = 1;
default_action.step = 0;
default_action.sig = 0;
p = &own_buf[5];
i = 0;
while (*p)
{
p++;
resume_info[i].leave_stopped = 0;
if (p[0] == 's' || p[0] == 'S')
resume_info[i].step = 1;
else if (p[0] == 'c' || p[0] == 'C')
resume_info[i].step = 0;
else
goto err;
if (p[0] == 'S' || p[0] == 'C')
{
int sig;
sig = strtol (p + 1, &q, 16);
if (p == q)
goto err;
p = q;
if (!target_signal_to_host_p (sig))
goto err;
resume_info[i].sig = target_signal_to_host (sig);
}
else
{
resume_info[i].sig = 0;
p = p + 1;
}
if (p[0] == 0)
{
resume_info[i].thread = -1;
default_action = resume_info[i];
/* Note: we don't increment i here, we'll overwrite this entry
the next time through. */
}
else if (p[0] == ':')
{
resume_info[i].thread = strtoul (p + 1, &q, 16);
if (p == q)
goto err;
p = q;
if (p[0] != ';' && p[0] != 0)
goto err;
i++;
}
}
resume_info[i] = default_action;
/* Still used in occasional places in the backend. */
if (n == 1 && resume_info[0].thread != -1)
cont_thread = resume_info[0].thread;
else
cont_thread = -1;
set_desired_inferior (0);
(*the_target->resume) (resume_info);
free (resume_info);
*signal = mywait (status, 1);
prepare_resume_reply (own_buf, *status, *signal);
return;
err:
/* No other way to report an error... */
strcpy (own_buf, "");
free (resume_info);
return;
}
/* Handle all of the extended 'v' packets. */
void
handle_v_requests (char *own_buf, char *status, int *signal)
{
if (strncmp (own_buf, "vCont;", 6) == 0)
{
handle_v_cont (own_buf, status, signal);
return;
}
if (strncmp (own_buf, "vCont?", 6) == 0)
{
strcpy (own_buf, "vCont;c;C;s;S");
return;
}
/* Otherwise we didn't know what packet it was. Say we didn't
understand it. */
own_buf[0] = 0;
return;
}
void
myresume (int step, int sig)
{
struct thread_resume resume_info[2];
int n = 0;
if (step || sig || (cont_thread != 0 && cont_thread != -1))
{
resume_info[0].thread
= ((struct inferior_list_entry *) current_inferior)->id;
resume_info[0].step = step;
resume_info[0].sig = sig;
resume_info[0].leave_stopped = 0;
n++;
}
resume_info[n].thread = -1;
resume_info[n].step = 0;
resume_info[n].sig = 0;
resume_info[n].leave_stopped = (cont_thread != 0 && cont_thread != -1);
(*the_target->resume) (resume_info);
}
static int attached;
static void
gdbserver_usage (void)
{
error ("Usage:\tgdbserver COMM PROG [ARGS ...]\n"
"\tgdbserver COMM --attach PID\n"
"\n"
"COMM may either be a tty device (for serial debugging), or \n"
"HOST:PORT to listen for a TCP connection.\n");
}
int
main (int argc, char *argv[])
{
char ch, status, *own_buf;
unsigned char mem_buf[2000];
int i = 0;
int signal;
unsigned int len;
CORE_ADDR mem_addr;
int bad_attach;
int pid;
char *arg_end;
if (setjmp (toplevel))
{
fprintf (stderr, "Exiting\n");
exit (1);
}
bad_attach = 0;
pid = 0;
attached = 0;
if (argc >= 3 && strcmp (argv[2], "--attach") == 0)
{
if (argc == 4
&& argv[3] != '\0'
&& (pid = strtoul (argv[3], &arg_end, 10)) != 0
&& *arg_end == '\0')
{
;
}
else
bad_attach = 1;
}
if (argc < 3 || bad_attach)
gdbserver_usage();
initialize_low ();
own_buf = malloc (PBUFSIZ);
if (pid == 0)
{
/* Wait till we are at first instruction in program. */
signal = start_inferior (&argv[2], &status);
/* We are now stopped at the first instruction of the target process */
}
else
{
switch (attach_inferior (pid, &status, &signal))
{
case -1:
error ("Attaching not supported on this target");
break;
default:
attached = 1;
break;
}
}
while (1)
{
remote_open (argv[1]);
restart:
setjmp (toplevel);
while (getpkt (own_buf) > 0)
{
unsigned char sig;
i = 0;
ch = own_buf[i++];
switch (ch)
{
case 'q':
handle_query (own_buf);
break;
case 'd':
remote_debug = !remote_debug;
break;
case 'D':
fprintf (stderr, "Detaching from inferior\n");
detach_inferior ();
write_ok (own_buf);
putpkt (own_buf);
remote_close ();
/* If we are attached, then we can exit. Otherwise, we need to
hang around doing nothing, until the child is gone. */
if (!attached)
{
int status, ret;
do {
ret = waitpid (signal_pid, &status, 0);
if (WIFEXITED (status) || WIFSIGNALED (status))
break;
} while (ret != -1 || errno != ECHILD);
}
exit (0);
case '!':
if (attached == 0)
{
extended_protocol = 1;
prepare_resume_reply (own_buf, status, signal);
}
else
{
/* We can not use the extended protocol if we are
attached, because we can not restart the running
program. So return unrecognized. */
own_buf[0] = '\0';
}
break;
case '?':
prepare_resume_reply (own_buf, status, signal);
break;
case 'H':
switch (own_buf[1])
{
case 'g':
general_thread = strtoul (&own_buf[2], NULL, 16);
write_ok (own_buf);
set_desired_inferior (1);
break;
case 'c':
cont_thread = strtoul (&own_buf[2], NULL, 16);
write_ok (own_buf);
break;
case 's':
step_thread = strtoul (&own_buf[2], NULL, 16);
write_ok (own_buf);
break;
default:
/* Silently ignore it so that gdb can extend the protocol
without compatibility headaches. */
own_buf[0] = '\0';
break;
}
break;
case 'g':
set_desired_inferior (1);
registers_to_string (own_buf);
break;
case 'G':
set_desired_inferior (1);
registers_from_string (&own_buf[1]);
write_ok (own_buf);
break;
case 'm':
decode_m_packet (&own_buf[1], &mem_addr, &len);
if (read_inferior_memory (mem_addr, mem_buf, len) == 0)
convert_int_to_ascii (mem_buf, own_buf, len);
else
write_enn (own_buf);
break;
case 'M':
decode_M_packet (&own_buf[1], &mem_addr, &len, mem_buf);
if (write_inferior_memory (mem_addr, mem_buf, len) == 0)
write_ok (own_buf);
else
write_enn (own_buf);
break;
case 'C':
convert_ascii_to_int (own_buf + 1, &sig, 1);
if (target_signal_to_host_p (sig))
signal = target_signal_to_host (sig);
else
signal = 0;
set_desired_inferior (0);
myresume (0, signal);
signal = mywait (&status, 1);
prepare_resume_reply (own_buf, status, signal);
break;
case 'S':
convert_ascii_to_int (own_buf + 1, &sig, 1);
if (target_signal_to_host_p (sig))
signal = target_signal_to_host (sig);
else
signal = 0;
set_desired_inferior (0);
myresume (1, signal);
signal = mywait (&status, 1);
prepare_resume_reply (own_buf, status, signal);
break;
case 'c':
set_desired_inferior (0);
myresume (0, 0);
signal = mywait (&status, 1);
prepare_resume_reply (own_buf, status, signal);
break;
case 's':
set_desired_inferior (0);
myresume (1, 0);
signal = mywait (&status, 1);
prepare_resume_reply (own_buf, status, signal);
break;
case 'Z':
{
char *lenptr;
char *dataptr;
CORE_ADDR addr = strtoul (&own_buf[3], &lenptr, 16);
int len = strtol (lenptr + 1, &dataptr, 16);
char type = own_buf[1];
if (the_target->insert_watchpoint == NULL
|| (type < '2' || type > '4'))
{
/* No watchpoint support or not a watchpoint command;
unrecognized either way. */
own_buf[0] = '\0';
}
else
{
int res;
res = (*the_target->insert_watchpoint) (type, addr, len);
if (res == 0)
write_ok (own_buf);
else if (res == 1)
/* Unsupported. */
own_buf[0] = '\0';
else
write_enn (own_buf);
}
break;
}
case 'z':
{
char *lenptr;
char *dataptr;
CORE_ADDR addr = strtoul (&own_buf[3], &lenptr, 16);
int len = strtol (lenptr + 1, &dataptr, 16);
char type = own_buf[1];
if (the_target->remove_watchpoint == NULL
|| (type < '2' || type > '4'))
{
/* No watchpoint support or not a watchpoint command;
unrecognized either way. */
own_buf[0] = '\0';
}
else
{
int res;
res = (*the_target->remove_watchpoint) (type, addr, len);
if (res == 0)
write_ok (own_buf);
else if (res == 1)
/* Unsupported. */
own_buf[0] = '\0';
else
write_enn (own_buf);
}
break;
}
case 'k':
fprintf (stderr, "Killing inferior\n");
kill_inferior ();
/* When using the extended protocol, we start up a new
debugging session. The traditional protocol will
exit instead. */
if (extended_protocol)
{
write_ok (own_buf);
fprintf (stderr, "GDBserver restarting\n");
/* Wait till we are at 1st instruction in prog. */
signal = start_inferior (&argv[2], &status);
goto restart;
break;
}
else
{
exit (0);
break;
}
case 'T':
if (mythread_alive (strtoul (&own_buf[1], NULL, 16)))
write_ok (own_buf);
else
write_enn (own_buf);
break;
case 'R':
/* Restarting the inferior is only supported in the
extended protocol. */
if (extended_protocol)
{
kill_inferior ();
write_ok (own_buf);
fprintf (stderr, "GDBserver restarting\n");
/* Wait till we are at 1st instruction in prog. */
signal = start_inferior (&argv[2], &status);
goto restart;
break;
}
else
{
/* It is a request we don't understand. Respond with an
empty packet so that gdb knows that we don't support this
request. */
own_buf[0] = '\0';
break;
}
case 'v':
/* Extended (long) request. */
handle_v_requests (own_buf, &status, &signal);
break;
default:
/* It is a request we don't understand. Respond with an
empty packet so that gdb knows that we don't support this
request. */
own_buf[0] = '\0';
break;
}
putpkt (own_buf);
if (status == 'W')
fprintf (stderr,
"\nChild exited with status %d\n", signal);
if (status == 'X')
fprintf (stderr, "\nChild terminated with signal = 0x%x\n",
signal);
if (status == 'W' || status == 'X')
{
if (extended_protocol)
{
fprintf (stderr, "Killing inferior\n");
kill_inferior ();
write_ok (own_buf);
fprintf (stderr, "GDBserver restarting\n");
/* Wait till we are at 1st instruction in prog. */
signal = start_inferior (&argv[2], &status);
goto restart;
break;
}
else
{
fprintf (stderr, "GDBserver exiting\n");
exit (0);
}
}
}
/* We come here when getpkt fails.
For the extended remote protocol we exit (and this is the only
way we gracefully exit!).
For the traditional remote protocol close the connection,
and re-open it at the top of the loop. */
if (extended_protocol)
{
remote_close ();
exit (0);
}
else
{
fprintf (stderr, "Remote side has terminated connection. "
"GDBserver will reopen the connection.\n");
remote_close ();
}
}
}
|