aboutsummaryrefslogtreecommitdiff
path: root/gdb/xml-syscall.c
blob: a43641893a60488a5ee47f70bd537cbbc6d2a108 (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
/* Functions that provide the mechanism to parse a syscall XML file
   and get its values.

   Copyright (C) 2009-2017 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 3 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, see <http://www.gnu.org/licenses/>.  */

#include "defs.h"
#include "gdbtypes.h"
#include "xml-support.h"
#include "xml-syscall.h"
#include "gdbarch.h"

/* For the struct syscall definition.  */
#include "target.h"

#include "filenames.h"

#ifndef HAVE_LIBEXPAT

/* Dummy functions to indicate that there's no support for fetching
   syscalls information.  */

static void
syscall_warn_user (void)
{
  static int have_warned = 0;
  if (!have_warned)
    {
      have_warned = 1;
      warning (_("Can not parse XML syscalls information; XML support was "
		 "disabled at compile time."));
    }
}

void
set_xml_syscall_file_name (struct gdbarch *gdbarch, const char *name)
{
  return;
}

void
get_syscall_by_number (struct gdbarch *gdbarch,
		       int syscall_number, struct syscall *s)
{
  syscall_warn_user ();
  s->number = syscall_number;
  s->name = NULL;
}

void
get_syscall_by_name (struct gdbarch *gdbarch, const char *syscall_name,
		     struct syscall *s)
{
  syscall_warn_user ();
  s->number = UNKNOWN_SYSCALL;
  s->name = syscall_name;
}

const char **
get_syscall_names (struct gdbarch *gdbarch)
{
  syscall_warn_user ();
  return NULL;
}

struct syscall *
get_syscalls_by_group (struct gdbarch *gdbarch, const char *group)
{
  syscall_warn_user ();
  return NULL;
}

const char **
get_syscall_group_names (struct gdbarch *gdbarch)
{
  syscall_warn_user ();
  return NULL;
}

#else /* ! HAVE_LIBEXPAT */

/* Structure which describes a syscall.  */
typedef struct syscall_desc
{
  /* The syscall number.  */

  int number;

  /* The syscall name.  */

  char *name;
} *syscall_desc_p;
DEF_VEC_P(syscall_desc_p);

/* Structure of a syscall group.  */
typedef struct syscall_group_desc
{
  /* The group name.  */

  char *name;

  /* The syscalls that are part of the group.  */

  VEC(syscall_desc_p) *syscalls;
} *syscall_group_desc_p;
DEF_VEC_P(syscall_group_desc_p);

/* Structure that represents syscalls information.  */
struct syscalls_info
{
  /* The syscalls.  */

  VEC(syscall_desc_p) *syscalls;

  /* The syscall groups.  */

  VEC(syscall_group_desc_p) *groups;

  /* Variable that will hold the last known data-directory.  This is
     useful to know whether we should re-read the XML info for the
     target.  */

  char *my_gdb_datadir;
};

/* Callback data for syscall information parsing.  */
struct syscall_parsing_data
{
  /* The syscalls_info we are building.  */

  struct syscalls_info *syscalls_info;
};

static struct syscalls_info *
allocate_syscalls_info (void)
{
  return XCNEW (struct syscalls_info);
}

static void
syscalls_info_free_syscalls_desc (struct syscall_desc *sd)
{
  xfree (sd->name);
}

/* Free syscall_group_desc members but not the structure itself.  */

static void
syscalls_info_free_syscall_group_desc (struct syscall_group_desc *sd)
{
  VEC_free (syscall_desc_p, sd->syscalls);
  xfree (sd->name);
}

static void
free_syscalls_info (void *arg)
{
  struct syscalls_info *syscalls_info = (struct syscalls_info *) arg;
  struct syscall_desc *sysdesc;
  struct syscall_group_desc *groupdesc;
  int i;

  xfree (syscalls_info->my_gdb_datadir);

  if (syscalls_info->syscalls != NULL)
    {
      for (i = 0;
	   VEC_iterate (syscall_desc_p, syscalls_info->syscalls, i, sysdesc);
	   i++)
	syscalls_info_free_syscalls_desc (sysdesc);
      VEC_free (syscall_desc_p, syscalls_info->syscalls);
    }

  if (syscalls_info->groups != NULL)
    {
      for (i = 0;
	   VEC_iterate (syscall_group_desc_p,
			syscalls_info->groups, i, groupdesc);
	   i++)
	syscalls_info_free_syscall_group_desc (groupdesc);

      VEC_free (syscall_group_desc_p, syscalls_info->groups);
    }

  xfree (syscalls_info);
}

static struct cleanup *
make_cleanup_free_syscalls_info (struct syscalls_info *syscalls_info)
{
  return make_cleanup (free_syscalls_info, syscalls_info);
}

/* Create a new syscall group.  Return pointer to the
   syscall_group_desc structure that represents the new group.  */

static struct syscall_group_desc *
syscall_group_create_syscall_group_desc (struct syscalls_info *syscalls_info,
					 const char *group)
{
  struct syscall_group_desc *groupdesc = XCNEW (struct syscall_group_desc);

  groupdesc->name = xstrdup (group);

  VEC_safe_push (syscall_group_desc_p, syscalls_info->groups, groupdesc);

  return groupdesc;
}

/* Add a syscall to the group.  If group doesn't exist, create it.  */

static void
syscall_group_add_syscall (struct syscalls_info *syscalls_info,
			   struct syscall_desc *syscall,
			   const char *group)
{
  struct syscall_group_desc *groupdesc = NULL;
  int i;

  /* Search for an existing group.  */
  for (i = 0;
       VEC_iterate (syscall_group_desc_p, syscalls_info->groups, i, groupdesc);
       i++)
    {
      if (strcmp (groupdesc->name, group) == 0)
	break;
    }

  if (groupdesc == NULL)
    {
      /* No group was found with this name.  We must create a new
	 one.  */
      groupdesc = syscall_group_create_syscall_group_desc (syscalls_info,
							   group);
    }

  VEC_safe_push (syscall_desc_p, groupdesc->syscalls, syscall);
}

static void
syscall_create_syscall_desc (struct syscalls_info *syscalls_info,
			     const char *name, int number,
			     char *groups)
{
  struct syscall_desc *sysdesc = XCNEW (struct syscall_desc);
  char *group;

  sysdesc->name = xstrdup (name);
  sysdesc->number = number;

  VEC_safe_push (syscall_desc_p, syscalls_info->syscalls, sysdesc);

  /*  Add syscall to its groups.  */
  if (groups != NULL)
    {
      for (group = strtok (groups, ",");
	   group != NULL;
	   group = strtok (NULL, ","))
	syscall_group_add_syscall (syscalls_info, sysdesc, group);
    }
}

/* Handle the start of a <syscall> element.  */
static void
syscall_start_syscall (struct gdb_xml_parser *parser,
                       const struct gdb_xml_element *element,
                       void *user_data, VEC(gdb_xml_value_s) *attributes)
{
  struct syscall_parsing_data *data = (struct syscall_parsing_data *) user_data;
  struct gdb_xml_value *attrs = VEC_address (gdb_xml_value_s, attributes);
  int len, i;
  /* syscall info.  */
  char *name = NULL;
  int number = 0;
  char *groups = NULL;

  len = VEC_length (gdb_xml_value_s, attributes);

  for (i = 0; i < len; i++)
    {
      if (strcmp (attrs[i].name, "name") == 0)
        name = (char *) attrs[i].value;
      else if (strcmp (attrs[i].name, "number") == 0)
        number = * (ULONGEST *) attrs[i].value;
      else if (strcmp (attrs[i].name, "groups") == 0)
        groups = (char *) attrs[i].value;
      else
        internal_error (__FILE__, __LINE__,
                        _("Unknown attribute name '%s'."), attrs[i].name);
    }

  gdb_assert (name);
  syscall_create_syscall_desc (data->syscalls_info, name, number, groups);
}


/* The elements and attributes of an XML syscall document.  */
static const struct gdb_xml_attribute syscall_attr[] = {
  { "number", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL },
  { "name", GDB_XML_AF_NONE, NULL, NULL },
  { "groups", GDB_XML_AF_OPTIONAL, NULL, NULL },
  { NULL, GDB_XML_AF_NONE, NULL, NULL }
};

static const struct gdb_xml_element syscalls_info_children[] = {
  { "syscall", syscall_attr, NULL,
    GDB_XML_EF_OPTIONAL | GDB_XML_EF_REPEATABLE,
    syscall_start_syscall, NULL },
  { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
};

static const struct gdb_xml_element syselements[] = {
  { "syscalls_info", NULL, syscalls_info_children,
    GDB_XML_EF_NONE, NULL, NULL },
  { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
};

static struct syscalls_info *
syscall_parse_xml (const char *document, xml_fetch_another fetcher,
                   void *fetcher_baton)
{
  struct cleanup *result_cleanup;
  struct syscall_parsing_data data;

  data.syscalls_info = allocate_syscalls_info ();
  result_cleanup = make_cleanup_free_syscalls_info (data.syscalls_info);

  if (gdb_xml_parse_quick (_("syscalls info"), NULL,
			   syselements, document, &data) == 0)
    {
      /* Parsed successfully.  */
      discard_cleanups (result_cleanup);
      return data.syscalls_info;
    }
  else
    {
      warning (_("Could not load XML syscalls info; ignoring"));
      do_cleanups (result_cleanup);
      return NULL;
    }
}

/* Function responsible for initializing the information
   about the syscalls.  It reads the XML file and fills the
   struct syscalls_info with the values.
   
   Returns the struct syscalls_info if the file is valid, NULL otherwise.  */
static struct syscalls_info *
xml_init_syscalls_info (const char *filename)
{
  char *full_file;
  struct syscalls_info *syscalls_info;
  struct cleanup *back_to;

  full_file = xml_fetch_content_from_file (filename, gdb_datadir);
  if (full_file == NULL)
    return NULL;

  back_to = make_cleanup (xfree, full_file);

  syscalls_info = syscall_parse_xml (full_file,
				     xml_fetch_content_from_file,
				     (void *) ldirname (filename).c_str ());
  do_cleanups (back_to);

  return syscalls_info;
}

/* Initializes the syscalls_info structure according to the
   architecture.  */
static void
init_syscalls_info (struct gdbarch *gdbarch)
{
  struct syscalls_info *syscalls_info = gdbarch_syscalls_info (gdbarch);
  const char *xml_syscall_file = gdbarch_xml_syscall_file (gdbarch);

  /* Should we re-read the XML info for this target?  */
  if (syscalls_info != NULL && syscalls_info->my_gdb_datadir != NULL
      && filename_cmp (syscalls_info->my_gdb_datadir, gdb_datadir) != 0)
    {
      /* The data-directory changed from the last time we used it.
	 It means that we have to re-read the XML info.  */
      free_syscalls_info (syscalls_info);
      syscalls_info = NULL;
      set_gdbarch_syscalls_info (gdbarch, NULL);
    }

  /* Did we succeed at initializing this?  */
  if (syscalls_info != NULL)
    return;

  syscalls_info = xml_init_syscalls_info (xml_syscall_file);

  /* If there was some error reading the XML file, we initialize
     gdbarch->syscalls_info anyway, in order to store information
     about our attempt.  */
  if (syscalls_info == NULL)
    syscalls_info = allocate_syscalls_info ();

  if (syscalls_info->syscalls == NULL)
    {
      if (xml_syscall_file != NULL)
	warning (_("Could not load the syscall XML file `%s/%s'."),
		 gdb_datadir, xml_syscall_file);
      else
	warning (_("There is no XML file to open."));

      warning (_("GDB will not be able to display "
		 "syscall names nor to verify if\n"
		 "any provided syscall numbers are valid."));
    }

  /* Saving the data-directory used to read this XML info.  */
  syscalls_info->my_gdb_datadir = xstrdup (gdb_datadir);

  set_gdbarch_syscalls_info (gdbarch, syscalls_info);
}

/* Search for a syscall group by its name.  Return syscall_group_desc
   structure for the group if found or NULL otherwise.  */

static struct syscall_group_desc *
syscall_group_get_group_by_name (const struct syscalls_info *syscalls_info,
				 const char *group)
{
  struct syscall_group_desc *groupdesc;
  int i;

  if (syscalls_info == NULL)
    return NULL;

  if (group == NULL)
    return NULL;

   /* Search for existing group.  */
  for (i = 0;
       VEC_iterate (syscall_group_desc_p, syscalls_info->groups, i, groupdesc);
       i++)
    {
      if (strcmp (groupdesc->name, group) == 0)
	return groupdesc;
    }

  return NULL;
}

static int
xml_get_syscall_number (struct gdbarch *gdbarch,
                        const char *syscall_name)
{
  struct syscalls_info *syscalls_info = gdbarch_syscalls_info (gdbarch);
  struct syscall_desc *sysdesc;
  int i;

  if (syscalls_info == NULL
      || syscall_name == NULL)
    return UNKNOWN_SYSCALL;

  for (i = 0;
       VEC_iterate(syscall_desc_p, syscalls_info->syscalls, i, sysdesc);
       i++)
    if (strcmp (sysdesc->name, syscall_name) == 0)
      return sysdesc->number;

  return UNKNOWN_SYSCALL;
}

static const char *
xml_get_syscall_name (struct gdbarch *gdbarch,
                      int syscall_number)
{
  struct syscalls_info *syscalls_info = gdbarch_syscalls_info (gdbarch);
  struct syscall_desc *sysdesc;
  int i;

  if (syscalls_info == NULL
      || syscall_number < 0)
    return NULL;

  for (i = 0;
       VEC_iterate(syscall_desc_p, syscalls_info->syscalls, i, sysdesc);
       i++)
    if (sysdesc->number == syscall_number)
      return sysdesc->name;

  return NULL;
}

static const char **
xml_list_of_syscalls (struct gdbarch *gdbarch)
{
  struct syscalls_info *syscalls_info = gdbarch_syscalls_info (gdbarch);
  struct syscall_desc *sysdesc;
  const char **names = NULL;
  int nsyscalls;
  int i;

  if (syscalls_info == NULL)
    return NULL;

  nsyscalls = VEC_length (syscall_desc_p, syscalls_info->syscalls);
  names = XNEWVEC (const char *, nsyscalls + 1);

  for (i = 0;
       VEC_iterate (syscall_desc_p, syscalls_info->syscalls, i, sysdesc);
       i++)
    names[i] = sysdesc->name;

  names[i] = NULL;

  return names;
}

/* Iterate over the syscall_group_desc element to return a list of
   syscalls that are part of the given group, terminated by an empty
   element.  If the syscall group doesn't exist, return NULL.  */

static struct syscall *
xml_list_syscalls_by_group (struct gdbarch *gdbarch, const char *group)
{
  struct syscalls_info *syscalls_info = gdbarch_syscalls_info (gdbarch);
  struct syscall_group_desc *groupdesc;
  struct syscall_desc *sysdesc;
  struct syscall *syscalls = NULL;
  int nsyscalls;
  int i;

  if (syscalls_info == NULL)
    return NULL;

  groupdesc = syscall_group_get_group_by_name (syscalls_info, group);
  if (groupdesc == NULL)
    return NULL;

  nsyscalls = VEC_length (syscall_desc_p, groupdesc->syscalls);
  syscalls = (struct syscall*) xmalloc ((nsyscalls + 1)
					* sizeof (struct syscall));

  for (i = 0;
       VEC_iterate (syscall_desc_p, groupdesc->syscalls, i, sysdesc);
       i++)
    {
      syscalls[i].name = sysdesc->name;
      syscalls[i].number = sysdesc->number;
    }

  /* Add final element marker.  */
  syscalls[i].name = NULL;
  syscalls[i].number = 0;

  return syscalls;
}

/* Return a NULL terminated list of syscall groups or an empty list, if
   no syscall group is available.  Return NULL, if there is no syscall
   information available.  */

static const char **
xml_list_of_groups (struct gdbarch *gdbarch)
{
  struct syscalls_info *syscalls_info = gdbarch_syscalls_info (gdbarch);
  struct syscall_group_desc *groupdesc;
  const char **names = NULL;
  int i;
  int ngroups;

  if (syscalls_info == NULL)
    return NULL;

  ngroups = VEC_length (syscall_group_desc_p, syscalls_info->groups);
  names = (const char**) xmalloc ((ngroups + 1) * sizeof (char *));

  for (i = 0;
       VEC_iterate (syscall_group_desc_p, syscalls_info->groups, i, groupdesc);
       i++)
    names[i] = groupdesc->name;

  names[i] = NULL;

  return names;
}

void
set_xml_syscall_file_name (struct gdbarch *gdbarch, const char *name)
{
  set_gdbarch_xml_syscall_file (gdbarch, name);
}

void
get_syscall_by_number (struct gdbarch *gdbarch,
		       int syscall_number, struct syscall *s)
{
  init_syscalls_info (gdbarch);

  s->number = syscall_number;
  s->name = xml_get_syscall_name (gdbarch, syscall_number);
}

void
get_syscall_by_name (struct gdbarch *gdbarch,
		     const char *syscall_name, struct syscall *s)
{
  init_syscalls_info (gdbarch);

  s->number = xml_get_syscall_number (gdbarch, syscall_name);
  s->name = syscall_name;
}

const char **
get_syscall_names (struct gdbarch *gdbarch)
{
  init_syscalls_info (gdbarch);

  return xml_list_of_syscalls (gdbarch);
}

/* See comment in xml-syscall.h.  */

struct syscall *
get_syscalls_by_group (struct gdbarch *gdbarch, const char *group)
{
  init_syscalls_info (gdbarch);

  return xml_list_syscalls_by_group (gdbarch, group);
}

/* See comment in xml-syscall.h.  */

const char **
get_syscall_group_names (struct gdbarch *gdbarch)
{
  init_syscalls_info (gdbarch);

  return xml_list_of_groups (gdbarch);
}

#endif /* ! HAVE_LIBEXPAT */