code.delx.au - pulseaudio/blob - src/polypcore/idxset.c

   1 /* $Id$ */
   2
   3 /***
   4   This file is part of polypaudio.
   5
   6   polypaudio is free software; you can redistribute it and/or modify
   7   it under the terms of the GNU Lesser General Public License as
   8   published by the Free Software Foundation; either version 2.1 of the
   9   License, or (at your option) any later version.
  10
  11   polypaudio is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   Lesser General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public
  17   License along with polypaudio; if not, write to the Free Software
  18   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  19   USA.
  20 ***/
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include <config.h>
  24 #endif
  25
  26 #include <stdio.h>
  27 #include <assert.h>
  28 #include <stdlib.h>
  29 #include <string.h>
  30
  31 #include <polyp/xmalloc.h>
  32
  33 #include "idxset.h"
  34
  35 typedef struct idxset_entry {
  36     void *data;
  37     uint32_t index;
  38     unsigned hash_value;
  39
  40     struct idxset_entry *hash_prev, *hash_next;
  41     struct idxset_entry* iterate_prev, *iterate_next;
  42 } idxset_entry;
  43
  44 struct pa_idxset {
  45     unsigned (*hash_func) (const void *p);
  46     int (*compare_func)(const void *a, const void *b);
  47
  48     unsigned hash_table_size, n_entries;
  49     idxset_entry **hash_table, **array, *iterate_list_head, *iterate_list_tail;
  50     uint32_t index, start_index, array_size;
  51 };
  52
  53 unsigned pa_idxset_string_hash_func(const void *p) {
  54     unsigned hash = 0;
  55     const char *c;
  56
  57     for (c = p; *c; c++)
  58         hash = 31 * hash + *c;
  59
  60     return hash;
  61 }
  62
  63 int pa_idxset_string_compare_func(const void *a, const void *b) {
  64     return strcmp(a, b);
  65 }
  66
  67 unsigned pa_idxset_trivial_hash_func(const void *p) {
  68     return (unsigned) (long) p;
  69 }
  70
  71 int pa_idxset_trivial_compare_func(const void *a, const void *b) {
  72     return a != b;
  73 }
  74
  75 pa_idxset* pa_idxset_new(unsigned (*hash_func) (const void *p), int (*compare_func) (const void*a, const void*b)) {
  76     pa_idxset *s;
  77
  78     s = pa_xnew(pa_idxset, 1);
  79     s->hash_func = hash_func ? hash_func : pa_idxset_trivial_hash_func;
  80     s->compare_func = compare_func ? compare_func : pa_idxset_trivial_compare_func;
  81     s->hash_table_size = 1023;
  82     s->hash_table = pa_xmalloc0(sizeof(idxset_entry*)*s->hash_table_size);
  83     s->array = NULL;
  84     s->array_size = 0;
  85     s->index = 0;
  86     s->start_index = 0;
  87     s->n_entries = 0;
  88
  89     s->iterate_list_head = s->iterate_list_tail = NULL;
  90
  91     return s;
  92 }
  93
  94 void pa_idxset_free(pa_idxset *s, void (*free_func) (void *p, void *userdata), void *userdata) {
  95     assert(s);
  96
  97     while (s->iterate_list_head) {
  98         idxset_entry *e = s->iterate_list_head;
  99         s->iterate_list_head = s->iterate_list_head->iterate_next;
 100
 101         if (free_func)
 102             free_func(e->data, userdata);
 103         pa_xfree(e);
 104     }
 105
 106     pa_xfree(s->hash_table);
 107     pa_xfree(s->array);
 108     pa_xfree(s);
 109 }
 110
 111 static idxset_entry* hash_scan(pa_idxset *s, idxset_entry* e, const void *p) {
 112     assert(p);
 113
 114     assert(s->compare_func);
 115     for (; e; e = e->hash_next)
 116         if (s->compare_func(e->data, p) == 0)
 117             return e;
 118
 119     return NULL;
 120 }
 121
 122 static void extend_array(pa_idxset *s, uint32_t idx) {
 123     uint32_t i, j, l;
 124     idxset_entry** n;
 125     assert(idx >= s->start_index);
 126
 127     if (idx < s->start_index + s->array_size)
 128         return;
 129
 130     for (i = 0; i < s->array_size; i++)
 131         if (s->array[i])
 132             break;
 133
 134     l = idx - s->start_index - i + 100;
 135     n = pa_xnew0(idxset_entry*, l);
 136
 137     for (j = 0; j < s->array_size-i; j++)
 138         n[j] = s->array[i+j];
 139
 140     pa_xfree(s->array);
 141
 142     s->array = n;
 143     s->array_size = l;
 144     s->start_index += i;
 145 }
 146
 147 static idxset_entry** array_index(pa_idxset*s, uint32_t idx) {
 148     if (idx >= s->start_index + s->array_size)
 149         return NULL;
 150
 151     if (idx < s->start_index)
 152         return NULL;
 153
 154     return s->array + (idx - s->start_index);
 155 }
 156
 157 int pa_idxset_put(pa_idxset*s, void *p, uint32_t *idx) {
 158     unsigned h;
 159     idxset_entry *e, **a;
 160     assert(s && p);
 161
 162     assert(s->hash_func);
 163     h = s->hash_func(p) % s->hash_table_size;
 164
 165     assert(s->hash_table);
 166     if ((e = hash_scan(s, s->hash_table[h], p))) {
 167         if (idx)
 168             *idx = e->index;
 169
 170         return -1;
 171     }
 172
 173     e = pa_xmalloc(sizeof(idxset_entry));
 174     e->data = p;
 175     e->index = s->index++;
 176     e->hash_value = h;
 177
 178     /* Insert into hash table */
 179     e->hash_next = s->hash_table[h];
 180     e->hash_prev = NULL;
 181     if (s->hash_table[h])
 182         s->hash_table[h]->hash_prev = e;
 183     s->hash_table[h] = e;
 184
 185     /* Insert into array */
 186     extend_array(s, e->index);
 187     a = array_index(s, e->index);
 188     assert(a && !*a);
 189     *a = e;
 190
 191     /* Insert into linked list */
 192     e->iterate_next = NULL;
 193     e->iterate_prev = s->iterate_list_tail;
 194     if (s->iterate_list_tail) {
 195         assert(s->iterate_list_head);
 196         s->iterate_list_tail->iterate_next = e;
 197     } else {
 198         assert(!s->iterate_list_head);
 199         s->iterate_list_head = e;
 200     }
 201     s->iterate_list_tail = e;
 202
 203     s->n_entries++;
 204     assert(s->n_entries >= 1);
 205
 206     if (idx)
 207         *idx = e->index;
 208
 209     return 0;
 210 }
 211
 212 void* pa_idxset_get_by_index(pa_idxset*s, uint32_t idx) {
 213     idxset_entry **a;
 214     assert(s);
 215
 216     if (!(a = array_index(s, idx)))
 217         return NULL;
 218
 219     if (!*a)
 220         return NULL;
 221
 222     return (*a)->data;
 223 }
 224
 225 void* pa_idxset_get_by_data(pa_idxset*s, const void *p, uint32_t *idx) {
 226     unsigned h;
 227     idxset_entry *e;
 228     assert(s && p);
 229
 230     assert(s->hash_func);
 231     h = s->hash_func(p) % s->hash_table_size;
 232
 233     assert(s->hash_table);
 234     if (!(e = hash_scan(s, s->hash_table[h], p)))
 235         return NULL;
 236
 237     if (idx)
 238         *idx = e->index;
 239
 240     return e->data;
 241 }
 242
 243 static void remove_entry(pa_idxset *s, idxset_entry *e) {
 244     idxset_entry **a;
 245     assert(s && e);
 246
 247     /* Remove from array */
 248     a = array_index(s, e->index);
 249     assert(a && *a && *a == e);
 250     *a = NULL;
 251
 252     /* Remove from linked list */
 253     if (e->iterate_next)
 254         e->iterate_next->iterate_prev = e->iterate_prev;
 255     else
 256         s->iterate_list_tail = e->iterate_prev;
 257
 258     if (e->iterate_prev)
 259         e->iterate_prev->iterate_next = e->iterate_next;
 260     else
 261         s->iterate_list_head = e->iterate_next;
 262
 263     /* Remove from hash table */
 264     if (e->hash_next)
 265         e->hash_next->hash_prev = e->hash_prev;
 266
 267     if (e->hash_prev)
 268         e->hash_prev->hash_next = e->hash_next;
 269     else
 270         s->hash_table[e->hash_value] = e->hash_next;
 271
 272     pa_xfree(e);
 273
 274     assert(s->n_entries >= 1);
 275     s->n_entries--;
 276 }
 277
 278 void* pa_idxset_remove_by_index(pa_idxset*s, uint32_t idx) {
 279     idxset_entry **a;
 280     void *data;
 281
 282     assert(s);
 283
 284     if (!(a = array_index(s, idx)))
 285         return NULL;
 286
 287     data = (*a)->data;
 288     remove_entry(s, *a);
 289
 290     return data;
 291 }
 292
 293 void* pa_idxset_remove_by_data(pa_idxset*s, const void *data, uint32_t *idx) {
 294     idxset_entry *e;
 295     unsigned h;
 296     void *r;
 297
 298     assert(s->hash_func);
 299     h = s->hash_func(data) % s->hash_table_size;
 300
 301     assert(s->hash_table);
 302     if (!(e = hash_scan(s, s->hash_table[h], data)))
 303         return NULL;
 304
 305     r = e->data;
 306     if (idx)
 307         *idx = e->index;
 308
 309     remove_entry(s, e);
 310
 311     return r;
 312 }
 313
 314 void* pa_idxset_rrobin(pa_idxset *s, uint32_t *idx) {
 315     idxset_entry **a, *e = NULL;
 316     assert(s && idx);
 317
 318     if ((a = array_index(s, *idx)) && *a)
 319         e = (*a)->iterate_next;
 320
 321     if (!e)
 322         e = s->iterate_list_head;
 323
 324     if (!e)
 325         return NULL;
 326
 327     *idx = e->index;
 328     return e->data;
 329 }
 330
 331 void* pa_idxset_first(pa_idxset *s, uint32_t *idx) {
 332     assert(s);
 333
 334     if (!s->iterate_list_head)
 335         return NULL;
 336
 337     if (idx)
 338         *idx = s->iterate_list_head->index;
 339     return s->iterate_list_head->data;
 340 }
 341
 342 void *pa_idxset_next(pa_idxset *s, uint32_t *idx) {
 343     idxset_entry **a, *e = NULL;
 344     assert(s && idx);
 345
 346     if ((a = array_index(s, *idx)) && *a)
 347         e = (*a)->iterate_next;
 348
 349     if (e) {
 350         *idx = e->index;
 351         return e->data;
 352     } else {
 353         *idx = PA_IDXSET_INVALID;
 354         return NULL;
 355     }
 356 }
 357
 358
 359 int pa_idxset_foreach(pa_idxset*s, int (*func)(void *p, uint32_t idx, int *del, void*userdata), void *userdata) {
 360     idxset_entry *e;
 361     assert(s && func);
 362
 363     e = s->iterate_list_head;
 364     while (e) {
 365         int del = 0, r;
 366         idxset_entry *n = e->iterate_next;
 367
 368         r = func(e->data, e->index, &del, userdata);
 369
 370         if (del)
 371             remove_entry(s, e);
 372
 373         if (r < 0)
 374             return r;
 375
 376         e = n;
 377     }
 378
 379     return 0;
 380 }
 381
 382 unsigned pa_idxset_size(pa_idxset*s) {
 383     assert(s);
 384     return s->n_entries;
 385 }
 386
 387 int pa_idxset_isempty(pa_idxset *s) {
 388     assert(s);
 389     return s->n_entries == 0;
 390 }
 391