summaryrefslogtreecommitdiff
path: root/gdb/corefile.c
blob: 2b5a392c55728592c22a5f064f2fcecd29a6b502 (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
/* Core dump and executable file functions above target vector, for GDB.

   Copyright (C) 1986, 1987, 1989, 1991, 1992, 1993, 1994, 1996, 1997, 1998,
   1999, 2000, 2001, 2003, 2006, 2007 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 "defs.h"
#include "gdb_string.h"
#include <errno.h>
#include <signal.h>
#include <fcntl.h>
#include "inferior.h"
#include "symtab.h"
#include "command.h"
#include "gdbcmd.h"
#include "bfd.h"
#include "target.h"
#include "gdbcore.h"
#include "dis-asm.h"
#include "gdb_stat.h"
#include "completer.h"
#include "exceptions.h"

/* Local function declarations.  */

extern void _initialize_core (void);
static void call_extra_exec_file_hooks (char *filename);

/* You can have any number of hooks for `exec_file_command' command to
   call.  If there's only one hook, it is set in exec_file_display
   hook.  If there are two or more hooks, they are set in
   exec_file_extra_hooks[], and deprecated_exec_file_display_hook is
   set to a function that calls all of them.  This extra complexity is
   needed to preserve compatibility with old code that assumed that
   only one hook could be set, and which called
   deprecated_exec_file_display_hook directly.  */

typedef void (*hook_type) (char *);

hook_type deprecated_exec_file_display_hook;	/* the original hook */
static hook_type *exec_file_extra_hooks;	/* array of additional hooks */
static int exec_file_hook_count = 0;	/* size of array */

/* Binary file diddling handle for the core file.  */

bfd *core_bfd = NULL;


/* Backward compatability with old way of specifying core files.  */

void
core_file_command (char *filename, int from_tty)
{
  struct target_ops *t;

  dont_repeat ();		/* Either way, seems bogus. */

  t = find_core_target ();
  if (t == NULL)
    error (_("GDB can't read core files on this machine."));

  if (!filename)
    (t->to_detach) (filename, from_tty);
  else
    (t->to_open) (filename, from_tty);
}


/* If there are two or more functions that wish to hook into
   exec_file_command, this function will call all of the hook
   functions.  */

static void
call_extra_exec_file_hooks (char *filename)
{
  int i;

  for (i = 0; i < exec_file_hook_count; i++)
    (*exec_file_extra_hooks[i]) (filename);
}

/* Call this to specify the hook for exec_file_command to call back.
   This is called from the x-window display code.  */

void
specify_exec_file_hook (void (*hook) (char *))
{
  hook_type *new_array;

  if (deprecated_exec_file_display_hook != NULL)
    {
      /* There's already a hook installed.  Arrange to have both it
       * and the subsequent hooks called. */
      if (exec_file_hook_count == 0)
	{
	  /* If this is the first extra hook, initialize the hook array.  */
	  exec_file_extra_hooks = (hook_type *) xmalloc (sizeof (hook_type));
	  exec_file_extra_hooks[0] = deprecated_exec_file_display_hook;
	  deprecated_exec_file_display_hook = call_extra_exec_file_hooks;
	  exec_file_hook_count = 1;
	}

      /* Grow the hook array by one and add the new hook to the end.
         Yes, it's inefficient to grow it by one each time but since
         this is hardly ever called it's not a big deal.  */
      exec_file_hook_count++;
      new_array =
	(hook_type *) xrealloc (exec_file_extra_hooks,
				exec_file_hook_count * sizeof (hook_type));
      exec_file_extra_hooks = new_array;
      exec_file_extra_hooks[exec_file_hook_count - 1] = hook;
    }
  else
    deprecated_exec_file_display_hook = hook;
}

/* The exec file must be closed before running an inferior.
   If it is needed again after the inferior dies, it must
   be reopened.  */

void
close_exec_file (void)
{
#if 0				/* FIXME */
  if (exec_bfd)
    bfd_tempclose (exec_bfd);
#endif
}

void
reopen_exec_file (void)
{
#if 0				/* FIXME */
  if (exec_bfd)
    bfd_reopen (exec_bfd);
#else
  char *filename;
  int res;
  struct stat st;
  long mtime;

  /* Don't do anything if there isn't an exec file. */
  if (exec_bfd == NULL)
    return;

  /* If the timestamp of the exec file has changed, reopen it. */
  filename = xstrdup (bfd_get_filename (exec_bfd));
  make_cleanup (xfree, filename);
  mtime = bfd_get_mtime (exec_bfd);
  res = stat (filename, &st);

  if (mtime && mtime != st.st_mtime)
    exec_file_attach (filename, 0);
#endif
}

/* If we have both a core file and an exec file,
   print a warning if they don't go together.  */

void
validate_files (void)
{
  if (exec_bfd && core_bfd)
    {
      if (!core_file_matches_executable_p (core_bfd, exec_bfd))
	warning (_("core file may not match specified executable file."));
      else if (bfd_get_mtime (exec_bfd) > bfd_get_mtime (core_bfd))
	warning (_("exec file is newer than core file."));
    }
}

/* Return the name of the executable file as a string.
   ERR nonzero means get error if there is none specified;
   otherwise return 0 in that case.  */

char *
get_exec_file (int err)
{
  if (exec_bfd)
    return bfd_get_filename (exec_bfd);
  if (!err)
    return NULL;

  error (_("No executable file specified.\n\
Use the \"file\" or \"exec-file\" command."));
  return NULL;
}


/* Report a memory error with error().  */

void
memory_error (int status, CORE_ADDR memaddr)
{
  struct ui_file *tmp_stream = mem_fileopen ();
  make_cleanup_ui_file_delete (tmp_stream);

  if (status == EIO)
    {
      /* Actually, address between memaddr and memaddr + len
         was out of bounds. */
      fprintf_unfiltered (tmp_stream, "Cannot access memory at address ");
      deprecated_print_address_numeric (memaddr, 1, tmp_stream);
    }
  else
    {
      fprintf_filtered (tmp_stream, "Error accessing memory address ");
      deprecated_print_address_numeric (memaddr, 1, tmp_stream);
      fprintf_filtered (tmp_stream, ": %s.",
		       safe_strerror (status));
    }

  error_stream (tmp_stream);
}

/* Same as target_read_memory, but report an error if can't read.  */
void
read_memory (CORE_ADDR memaddr, gdb_byte *myaddr, int len)
{
  int status;
  status = target_read_memory (memaddr, myaddr, len);
  if (status != 0)
    memory_error (status, memaddr);
}

/* Argument / return result struct for use with
   do_captured_read_memory_integer().  MEMADDR and LEN are filled in
   by gdb_read_memory_integer().  RESULT is the contents that were
   successfully read from MEMADDR of length LEN.  */

struct captured_read_memory_integer_arguments
{
  CORE_ADDR memaddr;
  int len;
  LONGEST result;
};

/* Helper function for gdb_read_memory_integer().  DATA must be a
   pointer to a captured_read_memory_integer_arguments struct. 
   Return 1 if successful.  Note that the catch_errors() interface
   will return 0 if an error occurred while reading memory.  This
   choice of return code is so that we can distinguish between
   success and failure.  */

static int
do_captured_read_memory_integer (void *data)
{
  struct captured_read_memory_integer_arguments *args = (struct captured_read_memory_integer_arguments*) data;
  CORE_ADDR memaddr = args->memaddr;
  int len = args->len;

  args->result = read_memory_integer (memaddr, len);

  return 1;
}

/* Read memory at MEMADDR of length LEN and put the contents in
   RETURN_VALUE.  Return 0 if MEMADDR couldn't be read and non-zero
   if successful.  */

int
safe_read_memory_integer (CORE_ADDR memaddr, int len, LONGEST *return_value)
{
  int status;
  struct captured_read_memory_integer_arguments args;
  args.memaddr = memaddr;
  args.len = len;

  status = catch_errors (do_captured_read_memory_integer, &args,
                        "", RETURN_MASK_ALL);
  if (status)
    *return_value = args.result;

  return status;
}

LONGEST
read_memory_integer (CORE_ADDR memaddr, int len)
{
  gdb_byte buf[sizeof (LONGEST)];

  read_memory (memaddr, buf, len);
  return extract_signed_integer (buf, len);
}

ULONGEST
read_memory_unsigned_integer (CORE_ADDR memaddr, int len)
{
  gdb_byte buf[sizeof (ULONGEST)];

  read_memory (memaddr, buf, len);
  return extract_unsigned_integer (buf, len);
}

void
read_memory_string (CORE_ADDR memaddr, char *buffer, int max_len)
{
  char *cp;
  int i;
  int cnt;

  cp = buffer;
  while (1)
    {
      if (cp - buffer >= max_len)
	{
	  buffer[max_len - 1] = '\0';
	  break;
	}
      cnt = max_len - (cp - buffer);
      if (cnt > 8)
	cnt = 8;
      read_memory (memaddr + (int) (cp - buffer), cp, cnt);
      for (i = 0; i < cnt && *cp; i++, cp++)
	;			/* null body */

      if (i < cnt && !*cp)
	break;
    }
}

CORE_ADDR
read_memory_typed_address (CORE_ADDR addr, struct type *type)
{
  gdb_byte *buf = alloca (TYPE_LENGTH (type));
  read_memory (addr, buf, TYPE_LENGTH (type));
  return extract_typed_address (buf, type);
}

/* Same as target_write_memory, but report an error if can't write.  */
void
write_memory (CORE_ADDR memaddr, const bfd_byte *myaddr, int len)
{
  int status;
  gdb_byte *bytes = alloca (len);
  
  memcpy (bytes, myaddr, len);
  status = target_write_memory (memaddr, bytes, len);
  if (status != 0)
    memory_error (status, memaddr);
}

/* Store VALUE at ADDR in the inferior as a LEN-byte unsigned integer.  */
void
write_memory_unsigned_integer (CORE_ADDR addr, int len, ULONGEST value)
{
  gdb_byte *buf = alloca (len);
  store_unsigned_integer (buf, len, value);
  write_memory (addr, buf, len);
}

/* Store VALUE at ADDR in the inferior as a LEN-byte signed integer.  */
void
write_memory_signed_integer (CORE_ADDR addr, int len, LONGEST value)
{
  gdb_byte *buf = alloca (len);
  store_signed_integer (buf, len, value);
  write_memory (addr, buf, len);
}



#if 0
/* Enable after 4.12.  It is not tested.  */

/* Search code.  Targets can just make this their search function, or
   if the protocol has a less general search function, they can call this
   in the cases it can't handle.  */
void
generic_search (int len, char *data, char *mask, CORE_ADDR startaddr,
		int increment, CORE_ADDR lorange, CORE_ADDR hirange,
		CORE_ADDR *addr_found, char *data_found)
{
  int i;
  CORE_ADDR curaddr = startaddr;

  while (curaddr >= lorange && curaddr < hirange)
    {
      read_memory (curaddr, data_found, len);
      for (i = 0; i < len; ++i)
	if ((data_found[i] & mask[i]) != data[i])
	  goto try_again;
      /* It matches.  */
      *addr_found = curaddr;
      return;

    try_again:
      curaddr += increment;
    }
  *addr_found = (CORE_ADDR) 0;
  return;
}
#endif /* 0 */

/* The current default bfd target.  Points to storage allocated for
   gnutarget_string.  */
char *gnutarget;

/* Same thing, except it is "auto" not NULL for the default case.  */
static char *gnutarget_string;
static void
show_gnutarget_string (struct ui_file *file, int from_tty,
		       struct cmd_list_element *c, const char *value)
{
  fprintf_filtered (file, _("The current BFD target is \"%s\".\n"), value);
}

static void set_gnutarget_command (char *, int, struct cmd_list_element *);

static void
set_gnutarget_command (char *ignore, int from_tty, struct cmd_list_element *c)
{
  if (strcmp (gnutarget_string, "auto") == 0)
    gnutarget = NULL;
  else
    gnutarget = gnutarget_string;
}

/* Set the gnutarget.  */
void
set_gnutarget (char *newtarget)
{
  if (gnutarget_string != NULL)
    xfree (gnutarget_string);
  gnutarget_string = savestring (newtarget, strlen (newtarget));
  set_gnutarget_command (NULL, 0, NULL);
}

void
_initialize_core (void)
{
  struct cmd_list_element *c;
  c = add_cmd ("core-file", class_files, core_file_command, _("\
Use FILE as core dump for examining memory and registers.\n\
No arg means have no core file.  This command has been superseded by the\n\
`target core' and `detach' commands."), &cmdlist);
  set_cmd_completer (c, filename_completer);

  
  add_setshow_string_noescape_cmd ("gnutarget", class_files,
				   &gnutarget_string, _("(\
Set the current BFD target."), _("\
Show the current BFD target."), _("\
Use `set gnutarget auto' to specify automatic detection."),
				   set_gnutarget_command,
				   show_gnutarget_string,
				   &setlist, &showlist);

  if (getenv ("GNUTARGET"))
    set_gnutarget (getenv ("GNUTARGET"));
  else
    set_gnutarget ("auto");
}