aboutsummaryrefslogtreecommitdiff
path: root/gdb/gdbserver/remote-utils.c
blob: 60403ff6bb481b305f6fef6e371b2a71aad512b2 (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
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
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
/* Remote utility routines for the remote server for GDB.
   Copyright (C) 1986, 1989, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001,
   2002, 2003, 2004, 2005, 2006
   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., 51 Franklin Street, Fifth Floor,
   Boston, MA 02110-1301, USA.  */

#include "server.h"
#include "terminal.h"
#include <stdio.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/file.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include <netdb.h>
#include <netinet/tcp.h>
#include <sys/ioctl.h>
#include <signal.h>
#include <fcntl.h>
#include <sys/time.h>
#include <unistd.h>
#include <arpa/inet.h>

#ifndef HAVE_SOCKLEN_T
typedef int socklen_t;
#endif

/* A cache entry for a successfully looked-up symbol.  */
struct sym_cache
{
  const char *name;
  CORE_ADDR addr;
  struct sym_cache *next;
};

/* The symbol cache.  */
static struct sym_cache *symbol_cache;

/* If this flag has been set, assume cache misses are
   failures.  */
int all_symbols_looked_up;

int remote_debug = 0;
struct ui_file *gdb_stdlog;

static int remote_desc;

/* FIXME headerize? */
extern int using_threads;
extern int debug_threads;

/* Open a connection to a remote debugger.
   NAME is the filename used for communication.  */

void
remote_open (char *name)
{
  int save_fcntl_flags;
  
  if (!strchr (name, ':'))
    {
      remote_desc = open (name, O_RDWR);
      if (remote_desc < 0)
	perror_with_name ("Could not open remote device");

#ifdef HAVE_TERMIOS
      {
	struct termios termios;
	tcgetattr (remote_desc, &termios);

	termios.c_iflag = 0;
	termios.c_oflag = 0;
	termios.c_lflag = 0;
	termios.c_cflag &= ~(CSIZE | PARENB);
	termios.c_cflag |= CLOCAL | CS8;
	termios.c_cc[VMIN] = 1;
	termios.c_cc[VTIME] = 0;

	tcsetattr (remote_desc, TCSANOW, &termios);
      }
#endif

#ifdef HAVE_TERMIO
      {
	struct termio termio;
	ioctl (remote_desc, TCGETA, &termio);

	termio.c_iflag = 0;
	termio.c_oflag = 0;
	termio.c_lflag = 0;
	termio.c_cflag &= ~(CSIZE | PARENB);
	termio.c_cflag |= CLOCAL | CS8;
	termio.c_cc[VMIN] = 1;
	termio.c_cc[VTIME] = 0;

	ioctl (remote_desc, TCSETA, &termio);
      }
#endif

#ifdef HAVE_SGTTY
      {
	struct sgttyb sg;

	ioctl (remote_desc, TIOCGETP, &sg);
	sg.sg_flags = RAW;
	ioctl (remote_desc, TIOCSETP, &sg);
      }
#endif

      fprintf (stderr, "Remote debugging using %s\n", name);
    }
  else
    {
      char *port_str;
      int port;
      struct sockaddr_in sockaddr;
      socklen_t tmp;
      int tmp_desc;

      port_str = strchr (name, ':');

      port = atoi (port_str + 1);

      tmp_desc = socket (PF_INET, SOCK_STREAM, 0);
      if (tmp_desc < 0)
	perror_with_name ("Can't open socket");

      /* Allow rapid reuse of this port. */
      tmp = 1;
      setsockopt (tmp_desc, SOL_SOCKET, SO_REUSEADDR, (char *) &tmp,
		  sizeof (tmp));

      sockaddr.sin_family = PF_INET;
      sockaddr.sin_port = htons (port);
      sockaddr.sin_addr.s_addr = INADDR_ANY;

      if (bind (tmp_desc, (struct sockaddr *) &sockaddr, sizeof (sockaddr))
	  || listen (tmp_desc, 1))
	perror_with_name ("Can't bind address");

      fprintf (stderr, "Listening on port %d\n", port);

      tmp = sizeof (sockaddr);
      remote_desc = accept (tmp_desc, (struct sockaddr *) &sockaddr, &tmp);
      if (remote_desc == -1)
	perror_with_name ("Accept failed");

      /* Enable TCP keep alive process. */
      tmp = 1;
      setsockopt (tmp_desc, SOL_SOCKET, SO_KEEPALIVE, (char *) &tmp, sizeof (tmp));

      /* Tell TCP not to delay small packets.  This greatly speeds up
         interactive response. */
      tmp = 1;
      setsockopt (remote_desc, IPPROTO_TCP, TCP_NODELAY,
		  (char *) &tmp, sizeof (tmp));

      close (tmp_desc);		/* No longer need this */

      signal (SIGPIPE, SIG_IGN);	/* If we don't do this, then gdbserver simply
					   exits when the remote side dies.  */

      /* Convert IP address to string.  */
      fprintf (stderr, "Remote debugging from host %s\n", 
         inet_ntoa (sockaddr.sin_addr));
    }

#if defined(F_SETFL) && defined (FASYNC)
  save_fcntl_flags = fcntl (remote_desc, F_GETFL, 0);
  fcntl (remote_desc, F_SETFL, save_fcntl_flags | FASYNC);
#if defined (F_SETOWN)
  fcntl (remote_desc, F_SETOWN, getpid ());
#endif
#endif
  disable_async_io ();
}

void
remote_close (void)
{
  close (remote_desc);
}

/* Convert hex digit A to a number.  */

static int
fromhex (int a)
{
  if (a >= '0' && a <= '9')
    return a - '0';
  else if (a >= 'a' && a <= 'f')
    return a - 'a' + 10;
  else
    error ("Reply contains invalid hex digit");
  return 0;
}

int
unhexify (char *bin, const char *hex, int count)
{
  int i;

  for (i = 0; i < count; i++)
    {
      if (hex[0] == 0 || hex[1] == 0)
        {
          /* Hex string is short, or of uneven length.
             Return the count that has been converted so far. */
          return i;
        }
      *bin++ = fromhex (hex[0]) * 16 + fromhex (hex[1]);
      hex += 2;
    }
  return i;
}

static void
decode_address (CORE_ADDR *addrp, const char *start, int len)
{
  CORE_ADDR addr;
  char ch;
  int i;

  addr = 0;
  for (i = 0; i < len; i++)
    {
      ch = start[i];
      addr = addr << 4;
      addr = addr | (fromhex (ch) & 0x0f);
    }
  *addrp = addr;
}

/* Convert number NIB to a hex digit.  */

static int
tohex (int nib)
{
  if (nib < 10)
    return '0' + nib;
  else
    return 'a' + nib - 10;
}

int
hexify (char *hex, const char *bin, int count)
{
  int i;

  /* May use a length, or a nul-terminated string as input. */
  if (count == 0)
    count = strlen (bin);

  for (i = 0; i < count; i++)
    {
      *hex++ = tohex ((*bin >> 4) & 0xf);
      *hex++ = tohex (*bin++ & 0xf);
    }
  *hex = 0;
  return i;
}

/* Send a packet to the remote machine, with error checking.
   The data of the packet is in BUF.  Returns >= 0 on success, -1 otherwise. */

int
putpkt (char *buf)
{
  int i;
  unsigned char csum = 0;
  char *buf2;
  char buf3[1];
  int cnt = strlen (buf);
  char *p;

  buf2 = malloc (PBUFSIZ);

  /* Copy the packet into buffer BUF2, encapsulating it
     and giving it a checksum.  */

  p = buf2;
  *p++ = '$';

  for (i = 0; i < cnt; i++)
    {
      csum += buf[i];
      *p++ = buf[i];
    }
  *p++ = '#';
  *p++ = tohex ((csum >> 4) & 0xf);
  *p++ = tohex (csum & 0xf);

  *p = '\0';

  /* Send it over and over until we get a positive ack.  */

  do
    {
      int cc;

      if (write (remote_desc, buf2, p - buf2) != p - buf2)
	{
	  perror ("putpkt(write)");
	  return -1;
	}

      if (remote_debug)
	{
	  fprintf (stderr, "putpkt (\"%s\"); [looking for ack]\n", buf2);
	  fflush (stderr);
	}
      cc = read (remote_desc, buf3, 1);
      if (remote_debug)
	{
	  fprintf (stderr, "[received '%c' (0x%x)]\n", buf3[0], buf3[0]);
	  fflush (stderr);
	}

      if (cc <= 0)
	{
	  if (cc == 0)
	    fprintf (stderr, "putpkt(read): Got EOF\n");
	  else
	    perror ("putpkt(read)");

	  free (buf2);
	  return -1;
	}

      /* Check for an input interrupt while we're here.  */
      if (buf3[0] == '\003')
	(*the_target->send_signal) (SIGINT);
    }
  while (buf3[0] != '+');

  free (buf2);
  return 1;			/* Success! */
}

/* Come here when we get an input interrupt from the remote side.  This
   interrupt should only be active while we are waiting for the child to do
   something.  About the only thing that should come through is a ^C, which
   will cause us to send a SIGINT to the child.  */

static void
input_interrupt (int unused)
{
  fd_set readset;
  struct timeval immediate = { 0, 0 };

  /* Protect against spurious interrupts.  This has been observed to
     be a problem under NetBSD 1.4 and 1.5.  */

  FD_ZERO (&readset);
  FD_SET (remote_desc, &readset);
  if (select (remote_desc + 1, &readset, 0, 0, &immediate) > 0)
    {
      int cc;
      char c = 0;
      
      cc = read (remote_desc, &c, 1);

      if (cc != 1 || c != '\003')
	{
	  fprintf (stderr, "input_interrupt, count = %d c = %d ('%c')\n",
		   cc, c, c);
	  return;
	}
      
      (*the_target->send_signal) (SIGINT);
    }
}

void
block_async_io (void)
{
  sigset_t sigio_set;
  sigemptyset (&sigio_set);
  sigaddset (&sigio_set, SIGIO);
  sigprocmask (SIG_BLOCK, &sigio_set, NULL);
}

void
unblock_async_io (void)
{
  sigset_t sigio_set;
  sigemptyset (&sigio_set);
  sigaddset (&sigio_set, SIGIO);
  sigprocmask (SIG_UNBLOCK, &sigio_set, NULL);
}

/* Asynchronous I/O support.  SIGIO must be enabled when waiting, in order to
   accept Control-C from the client, and must be disabled when talking to
   the client.  */

/* Current state of asynchronous I/O.  */
static int async_io_enabled;

/* Enable asynchronous I/O.  */
void
enable_async_io (void)
{
  if (async_io_enabled)
    return;

  signal (SIGIO, input_interrupt);
  async_io_enabled = 1;
}

/* Disable asynchronous I/O.  */
void
disable_async_io (void)
{
  if (!async_io_enabled)
    return;

  signal (SIGIO, SIG_IGN);
  async_io_enabled = 0;
}

/* Returns next char from remote GDB.  -1 if error.  */

static int
readchar (void)
{
  static char buf[BUFSIZ];
  static int bufcnt = 0;
  static char *bufp;

  if (bufcnt-- > 0)
    return *bufp++ & 0x7f;

  bufcnt = read (remote_desc, buf, sizeof (buf));

  if (bufcnt <= 0)
    {
      if (bufcnt == 0)
	fprintf (stderr, "readchar: Got EOF\n");
      else
	perror ("readchar");

      return -1;
    }

  bufp = buf;
  bufcnt--;
  return *bufp++ & 0x7f;
}

/* Read a packet from the remote machine, with error checking,
   and store it in BUF.  Returns length of packet, or negative if error. */

int
getpkt (char *buf)
{
  char *bp;
  unsigned char csum, c1, c2;
  int c;

  while (1)
    {
      csum = 0;

      while (1)
	{
	  c = readchar ();
	  if (c == '$')
	    break;
	  if (remote_debug)
	    {
	      fprintf (stderr, "[getpkt: discarding char '%c']\n", c);
	      fflush (stderr);
	    }

	  if (c < 0)
	    return -1;
	}

      bp = buf;
      while (1)
	{
	  c = readchar ();
	  if (c < 0)
	    return -1;
	  if (c == '#')
	    break;
	  *bp++ = c;
	  csum += c;
	}
      *bp = 0;

      c1 = fromhex (readchar ());
      c2 = fromhex (readchar ());

      if (csum == (c1 << 4) + c2)
	break;

      fprintf (stderr, "Bad checksum, sentsum=0x%x, csum=0x%x, buf=%s\n",
	       (c1 << 4) + c2, csum, buf);
      write (remote_desc, "-", 1);
    }

  if (remote_debug)
    {
      fprintf (stderr, "getpkt (\"%s\");  [sending ack] \n", buf);
      fflush (stderr);
    }

  write (remote_desc, "+", 1);

  if (remote_debug)
    {
      fprintf (stderr, "[sent ack]\n");
      fflush (stderr);
    }

  return bp - buf;
}

void
write_ok (char *buf)
{
  buf[0] = 'O';
  buf[1] = 'K';
  buf[2] = '\0';
}

void
write_enn (char *buf)
{
  /* Some day, we should define the meanings of the error codes... */
  buf[0] = 'E';
  buf[1] = '0';
  buf[2] = '1';
  buf[3] = '\0';
}

void
convert_int_to_ascii (unsigned char *from, char *to, int n)
{
  int nib;
  int ch;
  while (n--)
    {
      ch = *from++;
      nib = ((ch & 0xf0) >> 4) & 0x0f;
      *to++ = tohex (nib);
      nib = ch & 0x0f;
      *to++ = tohex (nib);
    }
  *to++ = 0;
}


void
convert_ascii_to_int (char *from, unsigned char *to, int n)
{
  int nib1, nib2;
  while (n--)
    {
      nib1 = fromhex (*from++);
      nib2 = fromhex (*from++);
      *to++ = (((nib1 & 0x0f) << 4) & 0xf0) | (nib2 & 0x0f);
    }
}

static char *
outreg (int regno, char *buf)
{
  if ((regno >> 12) != 0)
    *buf++ = tohex ((regno >> 12) & 0xf);
  if ((regno >> 8) != 0)
    *buf++ = tohex ((regno >> 8) & 0xf);
  *buf++ = tohex ((regno >> 4) & 0xf);
  *buf++ = tohex (regno & 0xf);
  *buf++ = ':';
  collect_register_as_string (regno, buf);
  buf += 2 * register_size (regno);
  *buf++ = ';';

  return buf;
}

void
new_thread_notify (int id)
{
  char own_buf[256];

  /* The `n' response is not yet part of the remote protocol.  Do nothing.  */
  if (1)
    return;

  if (server_waiting == 0)
    return;

  sprintf (own_buf, "n%x", id);
  disable_async_io ();
  putpkt (own_buf);
  enable_async_io ();
}

void
dead_thread_notify (int id)
{
  char own_buf[256];

  /* The `x' response is not yet part of the remote protocol.  Do nothing.  */
  if (1)
    return;

  sprintf (own_buf, "x%x", id);
  disable_async_io ();
  putpkt (own_buf);
  enable_async_io ();
}

void
prepare_resume_reply (char *buf, char status, unsigned char signo)
{
  int nib, sig;

  *buf++ = status;

  sig = (int)target_signal_from_host (signo);

  nib = ((sig & 0xf0) >> 4);
  *buf++ = tohex (nib);
  nib = sig & 0x0f;
  *buf++ = tohex (nib);

  if (status == 'T')
    {
      const char **regp = gdbserver_expedite_regs;

      if (the_target->stopped_by_watchpoint != NULL
	  && (*the_target->stopped_by_watchpoint) ())
	{
	  CORE_ADDR addr;
	  int i;

	  strncpy (buf, "watch:", 6);
	  buf += 6;

	  addr = (*the_target->stopped_data_address) ();

	  /* Convert each byte of the address into two hexadecimal chars.
	     Note that we take sizeof (void *) instead of sizeof (addr);
	     this is to avoid sending a 64-bit address to a 32-bit GDB.  */
	  for (i = sizeof (void *) * 2; i > 0; i--)
	    {
	      *buf++ = tohex ((addr >> (i - 1) * 4) & 0xf);
	    }
	  *buf++ = ';';
	}

      while (*regp)
	{
	  buf = outreg (find_regno (*regp), buf);
	  regp ++;
	}

      /* Formerly, if the debugger had not used any thread features we would not
	 burden it with a thread status response.  This was for the benefit of
	 GDB 4.13 and older.  However, in recent GDB versions the check
	 (``if (cont_thread != 0)'') does not have the desired effect because of
	 sillyness in the way that the remote protocol handles specifying a thread.
	 Since thread support relies on qSymbol support anyway, assume GDB can handle
	 threads.  */

      if (using_threads)
	{
	  unsigned int gdb_id_from_wait;

	  /* FIXME right place to set this? */
	  thread_from_wait = ((struct inferior_list_entry *)current_inferior)->id;
	  gdb_id_from_wait = thread_to_gdb_id (current_inferior);

	  if (debug_threads)
	    fprintf (stderr, "Writing resume reply for %ld\n\n", thread_from_wait);
	  /* This if (1) ought to be unnecessary.  But remote_wait in GDB
	     will claim this event belongs to inferior_ptid if we do not
	     specify a thread, and there's no way for gdbserver to know
	     what inferior_ptid is.  */
	  if (1 || old_thread_from_wait != thread_from_wait)
	    {
	      general_thread = thread_from_wait;
	      sprintf (buf, "thread:%x;", gdb_id_from_wait);
	      buf += strlen (buf);
	      old_thread_from_wait = thread_from_wait;
	    }
	}
    }
  /* For W and X, we're done.  */
  *buf++ = 0;
}

void
decode_m_packet (char *from, CORE_ADDR *mem_addr_ptr, unsigned int *len_ptr)
{
  int i = 0, j = 0;
  char ch;
  *mem_addr_ptr = *len_ptr = 0;

  while ((ch = from[i++]) != ',')
    {
      *mem_addr_ptr = *mem_addr_ptr << 4;
      *mem_addr_ptr |= fromhex (ch) & 0x0f;
    }

  for (j = 0; j < 4; j++)
    {
      if ((ch = from[i++]) == 0)
	break;
      *len_ptr = *len_ptr << 4;
      *len_ptr |= fromhex (ch) & 0x0f;
    }
}

void
decode_M_packet (char *from, CORE_ADDR *mem_addr_ptr, unsigned int *len_ptr,
		 unsigned char *to)
{
  int i = 0;
  char ch;
  *mem_addr_ptr = *len_ptr = 0;

  while ((ch = from[i++]) != ',')
    {
      *mem_addr_ptr = *mem_addr_ptr << 4;
      *mem_addr_ptr |= fromhex (ch) & 0x0f;
    }

  while ((ch = from[i++]) != ':')
    {
      *len_ptr = *len_ptr << 4;
      *len_ptr |= fromhex (ch) & 0x0f;
    }

  convert_ascii_to_int (&from[i++], to, *len_ptr);
}

/* Ask GDB for the address of NAME, and return it in ADDRP if found.
   Returns 1 if the symbol is found, 0 if it is not, -1 on error.  */

int
look_up_one_symbol (const char *name, CORE_ADDR *addrp)
{
  char own_buf[266], *p, *q;
  int len;
  struct sym_cache *sym;

  /* Check the cache first.  */
  for (sym = symbol_cache; sym; sym = sym->next)
    if (strcmp (name, sym->name) == 0)
      {
	*addrp = sym->addr;
	return 1;
      }

  /* If we've passed the call to thread_db_look_up_symbols, then
     anything not in the cache must not exist; we're not interested
     in any libraries loaded after that point, only in symbols in
     libpthread.so.  It might not be an appropriate time to look
     up a symbol, e.g. while we're trying to fetch registers.  */
  if (all_symbols_looked_up)
    return 0;

  /* Send the request.  */
  strcpy (own_buf, "qSymbol:");
  hexify (own_buf + strlen ("qSymbol:"), name, strlen (name));
  if (putpkt (own_buf) < 0)
    return -1;

  /* FIXME:  Eventually add buffer overflow checking (to getpkt?)  */
  len = getpkt (own_buf);
  if (len < 0)
    return -1;

  if (strncmp (own_buf, "qSymbol:", strlen ("qSymbol:")) != 0)
    {
      /* Malformed response.  */
      if (remote_debug)
	{
	  fprintf (stderr, "Malformed response to qSymbol, ignoring.\n");
	  fflush (stderr);
	}

      return -1;
    }

  p = own_buf + strlen ("qSymbol:");
  q = p;
  while (*q && *q != ':')
    q++;

  /* Make sure we found a value for the symbol.  */
  if (p == q || *q == '\0')
    return 0;

  decode_address (addrp, p, q - p);

  /* Save the symbol in our cache.  */
  sym = malloc (sizeof (*sym));
  sym->name = strdup (name);
  sym->addr = *addrp;
  sym->next = symbol_cache;
  symbol_cache = sym;

  return 1;
}