aboutsummaryrefslogtreecommitdiff
path: root/libctf/ctf-hash.c
blob: 1c37d7515b43839b9d15238da8427f807d48e49f (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
/* Interface to hashtable implementations.
   Copyright (C) 2006-2020 Free Software Foundation, Inc.

   This file is part of libctf.

   libctf 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, 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; see the file COPYING.  If not see
   <http://www.gnu.org/licenses/>.  */

#include <ctf-impl.h>
#include <string.h>
#include "libiberty.h"
#include "hashtab.h"

/* We have two hashtable implementations: one, ctf_dynhash_*(), is an interface to
   a dynamically-expanding hash with unknown size that should support addition
   of large numbers of items, and removal as well, and is used only at
   type-insertion time; the other, ctf_dynhash_*(), is an interface to a
   fixed-size hash from const char * -> ctf_id_t with number of elements
   specified at creation time, that should support addition of items but need
   not support removal.  These can be implemented by the same underlying hashmap
   if you wish.  */

typedef struct ctf_helem
{
  void *key;			 /* Either a pointer, or a coerced ctf_id_t.  */
  void *value;			 /* The value (possibly a coerced int).  */
  ctf_hash_free_fun key_free;
  ctf_hash_free_fun value_free;
} ctf_helem_t;

struct ctf_dynhash
{
  struct htab *htab;
  ctf_hash_free_fun key_free;
  ctf_hash_free_fun value_free;
};

/* Hash functions. */

unsigned int
ctf_hash_integer (const void *ptr)
{
  ctf_helem_t *hep = (ctf_helem_t *) ptr;

  return htab_hash_pointer (hep->key);
}

int
ctf_hash_eq_integer (const void *a, const void *b)
{
  ctf_helem_t *hep_a = (ctf_helem_t *) a;
  ctf_helem_t *hep_b = (ctf_helem_t *) b;

  return htab_eq_pointer (hep_a->key, hep_b->key);
}

unsigned int
ctf_hash_string (const void *ptr)
{
  ctf_helem_t *hep = (ctf_helem_t *) ptr;

  return htab_hash_string (hep->key);
}

int
ctf_hash_eq_string (const void *a, const void *b)
{
  ctf_helem_t *hep_a = (ctf_helem_t *) a;
  ctf_helem_t *hep_b = (ctf_helem_t *) b;

  return !strcmp((const char *) hep_a->key, (const char *) hep_b->key);
}

/* Hash a type_mapping_key.  */
unsigned int
ctf_hash_type_mapping_key (const void *ptr)
{
  ctf_helem_t *hep = (ctf_helem_t *) ptr;
  ctf_link_type_mapping_key_t *k = (ctf_link_type_mapping_key_t *) hep->key;

  return htab_hash_pointer (k->cltm_fp) + 59 * htab_hash_pointer ((void *) k->cltm_idx);
}

int
ctf_hash_eq_type_mapping_key (const void *a, const void *b)
{
  ctf_helem_t *hep_a = (ctf_helem_t *) a;
  ctf_helem_t *hep_b = (ctf_helem_t *) b;
  ctf_link_type_mapping_key_t *key_a = (ctf_link_type_mapping_key_t *) hep_a->key;
  ctf_link_type_mapping_key_t *key_b = (ctf_link_type_mapping_key_t *) hep_b->key;

  return (key_a->cltm_fp == key_b->cltm_fp)
    && (key_a->cltm_idx == key_b->cltm_idx);
}

/* The dynhash, used for hashes whose size is not known at creation time. */

/* Free a single ctf_helem.  */

static void
ctf_dynhash_item_free (void *item)
{
  ctf_helem_t *helem = item;

  if (helem->key_free && helem->key)
    helem->key_free (helem->key);
  if (helem->value_free && helem->value)
    helem->value_free (helem->value);
  free (helem);
}

ctf_dynhash_t *
ctf_dynhash_create (ctf_hash_fun hash_fun, ctf_hash_eq_fun eq_fun,
                    ctf_hash_free_fun key_free, ctf_hash_free_fun value_free)
{
  ctf_dynhash_t *dynhash;

  dynhash = malloc (sizeof (ctf_dynhash_t));
  if (!dynhash)
    return NULL;

  /* 7 is arbitrary and untested for now..  */
  if ((dynhash->htab = htab_create_alloc (7, (htab_hash) hash_fun, eq_fun,
                                          ctf_dynhash_item_free, xcalloc, free)) == NULL)
    {
      free (dynhash);
      return NULL;
    }

  dynhash->key_free = key_free;
  dynhash->value_free = value_free;

  return dynhash;
}

static ctf_helem_t **
ctf_hashtab_lookup (struct htab *htab, const void *key, enum insert_option insert)
{
  ctf_helem_t tmp = { .key = (void *) key };
  return (ctf_helem_t **) htab_find_slot (htab, &tmp, insert);
}

static ctf_helem_t *
ctf_hashtab_insert (struct htab *htab, void *key, void *value,
		    ctf_hash_free_fun key_free,
		    ctf_hash_free_fun value_free)
{
  ctf_helem_t **slot;

  slot = ctf_hashtab_lookup (htab, key, INSERT);

  if (!slot)
    {
      errno = -ENOMEM;
      return NULL;
    }

  if (!*slot)
    {
      *slot = malloc (sizeof (ctf_helem_t));
      if (!*slot)
	return NULL;
      (*slot)->key = key;
    }
  else
    {
      if (key_free)
	  key_free (key);
      if (value_free)
	  value_free ((*slot)->value);
    }
  (*slot)->value = value;
  return *slot;
}

int
ctf_dynhash_insert (ctf_dynhash_t *hp, void *key, void *value)
{
  ctf_helem_t *slot;

  slot = ctf_hashtab_insert (hp->htab, key, value,
			     hp->key_free, hp->value_free);

  if (!slot)
    return errno;

  /* We need to keep the key_free and value_free around in each item because the
     del function has no visibility into the hash as a whole, only into the
     individual items.  */

  slot->key_free = hp->key_free;
  slot->value_free = hp->value_free;

  return 0;
}

void
ctf_dynhash_remove (ctf_dynhash_t *hp, const void *key)
{
  ctf_helem_t hep = { (void *) key, NULL, NULL, NULL };
  htab_remove_elt (hp->htab, &hep);
}

void
ctf_dynhash_empty (ctf_dynhash_t *hp)
{
  htab_empty (hp->htab);
}

size_t
ctf_dynhash_elements (ctf_dynhash_t *hp)
{
  return htab_elements (hp->htab);
}

void *
ctf_dynhash_lookup (ctf_dynhash_t *hp, const void *key)
{
  ctf_helem_t **slot;

  slot = ctf_hashtab_lookup (hp->htab, key, NO_INSERT);

  if (slot)
    return (*slot)->value;

  return NULL;
}

/* TRUE/FALSE return.  */
int
ctf_dynhash_lookup_kv (ctf_dynhash_t *hp, const void *key,
		       const void **orig_key, void **value)
{
  ctf_helem_t **slot;

  slot = ctf_hashtab_lookup (hp->htab, key, NO_INSERT);

  if (slot)
    {
      if (orig_key)
	*orig_key = (*slot)->key;
      if (value)
	*value = (*slot)->value;
      return 1;
    }
  return 0;
}

typedef struct ctf_traverse_cb_arg
{
  ctf_hash_iter_f fun;
  void *arg;
} ctf_traverse_cb_arg_t;

static int
ctf_hashtab_traverse (void **slot, void *arg_)
{
  ctf_helem_t *helem = *((ctf_helem_t **) slot);
  ctf_traverse_cb_arg_t *arg = (ctf_traverse_cb_arg_t *) arg_;

  arg->fun (helem->key, helem->value, arg->arg);
  return 1;
}

void
ctf_dynhash_iter (ctf_dynhash_t *hp, ctf_hash_iter_f fun, void *arg_)
{
  ctf_traverse_cb_arg_t arg = { fun, arg_ };
  htab_traverse (hp->htab, ctf_hashtab_traverse, &arg);
}

typedef struct ctf_traverse_find_cb_arg
{
  ctf_hash_iter_find_f fun;
  void *arg;
  void *found_key;
} ctf_traverse_find_cb_arg_t;

static int
ctf_hashtab_traverse_find (void **slot, void *arg_)
{
  ctf_helem_t *helem = *((ctf_helem_t **) slot);
  ctf_traverse_find_cb_arg_t *arg = (ctf_traverse_find_cb_arg_t *) arg_;

  if (arg->fun (helem->key, helem->value, arg->arg))
    {
      arg->found_key = helem->key;
      return 0;
    }
  return 1;
}

void *
ctf_dynhash_iter_find (ctf_dynhash_t *hp, ctf_hash_iter_find_f fun, void *arg_)
{
  ctf_traverse_find_cb_arg_t arg = { fun, arg_, NULL };
  htab_traverse (hp->htab, ctf_hashtab_traverse_find, &arg);
  return arg.found_key;
}

typedef struct ctf_traverse_remove_cb_arg
{
  struct htab *htab;
  ctf_hash_iter_remove_f fun;
  void *arg;
} ctf_traverse_remove_cb_arg_t;

static int
ctf_hashtab_traverse_remove (void **slot, void *arg_)
{
  ctf_helem_t *helem = *((ctf_helem_t **) slot);
  ctf_traverse_remove_cb_arg_t *arg = (ctf_traverse_remove_cb_arg_t *) arg_;

  if (arg->fun (helem->key, helem->value, arg->arg))
    htab_clear_slot (arg->htab, slot);
  return 1;
}

void
ctf_dynhash_iter_remove (ctf_dynhash_t *hp, ctf_hash_iter_remove_f fun,
                         void *arg_)
{
  ctf_traverse_remove_cb_arg_t arg = { hp->htab, fun, arg_ };
  htab_traverse (hp->htab, ctf_hashtab_traverse_remove, &arg);
}

void
ctf_dynhash_destroy (ctf_dynhash_t *hp)
{
  if (hp != NULL)
    htab_delete (hp->htab);
  free (hp);
}

/* ctf_hash, used for fixed-size maps from const char * -> ctf_id_t without
   removal.  This is a straight cast of a hashtab.  */

ctf_hash_t *
ctf_hash_create (unsigned long nelems, ctf_hash_fun hash_fun,
		 ctf_hash_eq_fun eq_fun)
{
  return (ctf_hash_t *) htab_create_alloc (nelems, (htab_hash) hash_fun,
					   eq_fun, free, xcalloc, free);
}

uint32_t
ctf_hash_size (const ctf_hash_t *hp)
{
  return htab_elements ((struct htab *) hp);
}

int
ctf_hash_insert_type (ctf_hash_t *hp, ctf_file_t *fp, uint32_t type,
		      uint32_t name)
{
  const char *str = ctf_strraw (fp, name);

  if (type == 0)
    return EINVAL;

  if (str == NULL
      && CTF_NAME_STID (name) == CTF_STRTAB_1
      && fp->ctf_syn_ext_strtab == NULL
      && fp->ctf_str[CTF_NAME_STID (name)].cts_strs == NULL)
    return ECTF_STRTAB;

  if (str == NULL)
    return ECTF_BADNAME;

  if (str[0] == '\0')
    return 0;		   /* Just ignore empty strings on behalf of caller.  */

  if (ctf_hashtab_insert ((struct htab *) hp, (char *) str,
			  (void *) (ptrdiff_t) type, NULL, NULL) != NULL)
    return 0;
  return errno;
}

/* if the key is already in the hash, override the previous definition with
   this new official definition. If the key is not present, then call
   ctf_hash_insert_type() and hash it in.  */
int
ctf_hash_define_type (ctf_hash_t *hp, ctf_file_t *fp, uint32_t type,
                      uint32_t name)
{
  /* This matches the semantics of ctf_hash_insert_type() in this
     implementation anyway.  */

  return ctf_hash_insert_type (hp, fp, type, name);
}

ctf_id_t
ctf_hash_lookup_type (ctf_hash_t *hp, ctf_file_t *fp __attribute__ ((__unused__)),
		      const char *key)
{
  ctf_helem_t **slot;

  slot = ctf_hashtab_lookup ((struct htab *) hp, key, NO_INSERT);

  if (slot)
    return (ctf_id_t) ((*slot)->value);

  return 0;
}

void
ctf_hash_destroy (ctf_hash_t *hp)
{
  if (hp != NULL)
    htab_delete ((struct htab *) hp);
}