dlls/dbghelp/storage.c

   1 /*
   2  * Various storage structures (pool allocation, vector, hash table)
   3  *
   4  * Copyright (C) 1993, Eric Youngdale.
   5  *               2004, Eric Pouech
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this library; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  20  */
  21
  22
  23 #include "config.h"
  24 #include <assert.h>
  25 #include <stdlib.h>
  26 #include "wine/debug.h"
  27
  28 #include "dbghelp_private.h"
  29 #ifdef USE_STATS
  30 #include <math.h>
  31 #endif
  32
  33 WINE_DEFAULT_DEBUG_CHANNEL(dbghelp);
  34
  35 struct pool_arena
  36 {
  37     struct pool_arena*  next;
  38     char*               current;
  39 };
  40
  41 void pool_init(struct pool* a, unsigned arena_size)
  42 {
  43     a->arena_size = arena_size;
  44     a->first = NULL;
  45 }
  46
  47 void pool_destroy(struct pool* pool)
  48 {
  49     struct pool_arena*  arena;
  50     struct pool_arena*  next;
  51
  52 #ifdef USE_STATS
  53     unsigned    alloc, used, num;
  54
  55     for (alloc = used = num = 0, arena = pool->first; arena; arena = arena->next)
  56     {
  57         alloc += pool->arena_size;
  58         used += arena->current - (char*)arena;
  59         num++;
  60     }
  61     FIXME("STATS: pool %p has allocated %u kbytes, used %u kbytes in %u arenas,\n"
  62           "\t\t\t\tnon-allocation ratio: %.2f%%\n",
  63           pool, alloc >> 10, used >> 10, num, 100.0 - (float)used / (float)alloc * 100.0);
  64 #endif
  65
  66     for (arena = pool->first; arena; arena = next)
  67     {
  68         next = arena->next;
  69         HeapFree(GetProcessHeap(), 0, arena);
  70     }
  71     pool_init(pool, 0);
  72 }
  73
  74 void* pool_alloc(struct pool* pool, unsigned len)
  75 {
  76     struct pool_arena** parena;
  77     struct pool_arena*  arena;
  78     void*               ret;
  79
  80     len = (len + 3) & ~3; /* round up size on DWORD boundary */
  81     assert(sizeof(struct pool_arena) + len <= pool->arena_size && len);
  82
  83     for (parena = &pool->first; *parena; parena = &(*parena)->next)
  84     {
  85         if ((char*)(*parena) + pool->arena_size - (*parena)->current >= len)
  86         {
  87             ret = (*parena)->current;
  88             (*parena)->current += len;
  89             return ret;
  90         }
  91     }
  92
  93     arena = HeapAlloc(GetProcessHeap(), 0, pool->arena_size);
  94     if (!arena) {FIXME("OOM\n");return NULL;}
  95
  96     *parena = arena;
  97
  98     ret = (char*)arena + sizeof(*arena);
  99     arena->next = NULL;
 100     arena->current = (char*)ret + len;
 101     return ret;
 102 }
 103
 104 static struct pool_arena* pool_is_last(struct pool* pool, void* p, unsigned old_size)
 105 {
 106     struct pool_arena*  arena;
 107
 108     for (arena = pool->first; arena; arena = arena->next)
 109     {
 110         if (arena->current == (char*)p + old_size) return arena;
 111     }
 112     return NULL;
 113 }
 114
 115 static void* pool_realloc(struct pool* pool, void* p, unsigned old_size, unsigned new_size)
 116 {
 117     struct pool_arena*  arena;
 118     void*               new;
 119
 120     if ((arena = pool_is_last(pool, p, old_size)) &&
 121         (char*)p + new_size <= (char*)arena + pool->arena_size)
 122     {
 123         arena->current = (char*)p + new_size;
 124         return p;
 125     }
 126     if ((new = pool_alloc(pool, new_size)) && old_size)
 127         memcpy(new, p, min(old_size, new_size));
 128     return new;
 129 }
 130
 131 char* pool_strdup(struct pool* pool, const char* str)
 132 {
 133     char* ret;
 134     if ((ret = pool_alloc(pool, strlen(str) + 1))) strcpy(ret, str);
 135     return ret;
 136 }
 137
 138 void vector_init(struct vector* v, unsigned esz, unsigned bucket_sz)
 139 {
 140     v->buckets = NULL;
 141     /* align size on DWORD boundaries */
 142     v->elt_size = (esz + 3) & ~3;
 143     switch (bucket_sz)
 144     {
 145     case    2: v->shift =  1; break;
 146     case    4: v->shift =  2; break;
 147     case    8: v->shift =  3; break;
 148     case   16: v->shift =  4; break;
 149     case   32: v->shift =  5; break;
 150     case   64: v->shift =  6; break;
 151     case  128: v->shift =  7; break;
 152     case  256: v->shift =  8; break;
 153     case  512: v->shift =  9; break;
 154     case 1024: v->shift = 10; break;
 155     default: assert(0);
 156     }
 157     v->num_buckets = 0;
 158     v->num_elts = 0;
 159 }
 160
 161 unsigned vector_length(const struct vector* v)
 162 {
 163     return v->num_elts;
 164 }
 165
 166 void* vector_at(const struct vector* v, unsigned pos)
 167 {
 168     unsigned o;
 169
 170     if (pos >= v->num_elts) return NULL;
 171     o = pos & ((1 << v->shift) - 1);
 172     return (char*)v->buckets[pos >> v->shift] + o * v->elt_size;
 173 }
 174
 175 void* vector_add(struct vector* v, struct pool* pool)
 176 {
 177     unsigned    ncurr = v->num_elts++;
 178
 179     /* check that we don't wrap around */
 180     assert(v->num_elts > ncurr);
 181     if (ncurr == (v->num_buckets << v->shift))
 182     {
 183         v->buckets = pool_realloc(pool, v->buckets,
 184                                   v->num_buckets * sizeof(void*),
 185                                   (v->num_buckets + 1) * sizeof(void*));
 186         v->buckets[v->num_buckets] = pool_alloc(pool, v->elt_size << v->shift);
 187         return v->buckets[v->num_buckets++];
 188     }
 189     return vector_at(v, ncurr);
 190 }
 191
 192 static unsigned vector_position(const struct vector* v, const void* elt)
 193 {
 194     int i;
 195
 196     for (i = 0; i < v->num_buckets; i++)
 197     {
 198         if (v->buckets[i] <= elt &&
 199             (const char*)elt < (const char*)v->buckets[i] + (v->elt_size << v->shift))
 200         {
 201             return (i << v->shift) +
 202                 ((const char*)elt - (const char*)v->buckets[i]) / v->elt_size;
 203         }
 204     }
 205     assert(0);
 206     return 0;
 207 }
 208
 209 void* vector_iter_up(const struct vector* v, void* elt)
 210 {
 211     unsigned    pos;
 212
 213     if (!elt) return vector_at(v, 0);
 214     pos = vector_position(v, elt) + 1;
 215     if (pos >= vector_length(v)) return NULL;
 216     return vector_at(v, pos);
 217 }
 218
 219 void* vector_iter_down(const struct vector* v, void* elt)
 220 {
 221     unsigned    pos;
 222     if (!elt) return vector_at(v, vector_length(v) - 1);
 223     pos = vector_position(v, elt);
 224     if (pos == 0) return NULL;
 225     return vector_at(v, pos - 1);
 226 }
 227
 228 /* We construct the sparse array as two vectors (of equal size)
 229  * The first vector (key2index) is the lookup table between the key and
 230  * an index in the second vector (elements)
 231  * When inserting an element, it's always appended in second vector (and
 232  * never moved in memory later on), only the first vector is reordered
 233  */
 234 struct key2index
 235 {
 236     unsigned long       key;
 237     unsigned            index;
 238 };
 239
 240 void sparse_array_init(struct sparse_array* sa, unsigned elt_sz, unsigned bucket_sz)
 241 {
 242     vector_init(&sa->key2index, sizeof(struct key2index), bucket_sz);
 243     vector_init(&sa->elements, elt_sz, bucket_sz);
 244 }
 245
 246 /******************************************************************
 247  *              sparse_array_lookup
 248  *
 249  * Returns the first index which key is >= at passed key
 250  */
 251 static struct key2index* sparse_array_lookup(const struct sparse_array* sa,
 252                                              unsigned long key, unsigned* idx)
 253 {
 254     struct key2index*   pk2i;
 255     unsigned            low, high;
 256
 257     if (!sa->elements.num_elts)
 258     {
 259         *idx = 0;
 260         return NULL;
 261     }
 262     high = sa->elements.num_elts;
 263     pk2i = vector_at(&sa->key2index, high - 1);
 264     if (pk2i->key < key)
 265     {
 266         *idx = high;
 267         return NULL;
 268     }
 269     if (pk2i->key == key)
 270     {
 271         *idx = high - 1;
 272         return pk2i;
 273     }
 274     low = 0;
 275     pk2i = vector_at(&sa->key2index, low);
 276     if (pk2i->key >= key)
 277     {
 278         *idx = 0;
 279         return pk2i;
 280     }
 281     /* now we have: sa(lowest key) < key < sa(highest key) */
 282     while (low < high)
 283     {
 284         *idx = (low + high) / 2;
 285         pk2i = vector_at(&sa->key2index, *idx);
 286         if (pk2i->key > key)            high = *idx;
 287         else if (pk2i->key < key)       low = *idx + 1;
 288         else                            return pk2i;
 289     }
 290     /* binary search could return exact item, we search for highest one
 291      * below the key
 292      */
 293     if (pk2i->key < key)
 294         pk2i = vector_at(&sa->key2index, ++(*idx));
 295     return pk2i;
 296 }
 297
 298 void*   sparse_array_find(const struct sparse_array* sa, unsigned long key)
 299 {
 300     unsigned            idx;
 301     struct key2index*   pk2i;
 302
 303     if ((pk2i = sparse_array_lookup(sa, key, &idx)) && pk2i->key == key)
 304         return vector_at(&sa->elements, pk2i->index);
 305     return NULL;
 306 }
 307
 308 void*   sparse_array_add(struct sparse_array* sa, unsigned long key,
 309                          struct pool* pool)
 310 {
 311     unsigned            idx, i;
 312     struct key2index*   pk2i;
 313     struct key2index*   to;
 314
 315     pk2i = sparse_array_lookup(sa, key, &idx);
 316     if (pk2i && pk2i->key == key)
 317     {
 318         FIXME("re adding an existing key\n");
 319         return NULL;
 320     }
 321     to = vector_add(&sa->key2index, pool);
 322     if (pk2i)
 323     {
 324         /* we need to shift vector's content... */
 325         /* let's do it brute force... (FIXME) */
 326         assert(sa->key2index.num_elts >= 2);
 327         for (i = sa->key2index.num_elts - 1; i > idx; i--)
 328         {
 329             pk2i = vector_at(&sa->key2index, i - 1);
 330             *to = *pk2i;
 331             to = pk2i;
 332         }
 333     }
 334
 335     to->key = key;
 336     to->index = sa->elements.num_elts;
 337
 338     return vector_add(&sa->elements, pool);
 339 }
 340
 341 unsigned sparse_array_length(const struct sparse_array* sa)
 342 {
 343     return sa->elements.num_elts;
 344 }
 345
 346 unsigned hash_table_hash(const char* name, unsigned num_buckets)
 347 {
 348     unsigned    hash = 0;
 349     while (*name)
 350     {
 351         hash += *name++;
 352         hash += (hash << 10);
 353         hash ^= (hash >> 6);
 354     }
 355     hash += (hash << 3);
 356     hash ^= (hash >> 11);
 357     hash += (hash << 15);
 358     return hash % num_buckets;
 359 }
 360
 361 void hash_table_init(struct pool* pool, struct hash_table* ht, unsigned num_buckets)
 362 {
 363     ht->num_elts = 0;
 364     ht->buckets = pool_alloc(pool, num_buckets * sizeof(struct hash_table_elt*));
 365     assert(ht->buckets);
 366     ht->num_buckets = num_buckets;
 367     memset(ht->buckets, 0, num_buckets * sizeof(struct hash_table_elt*));
 368 }
 369
 370 void hash_table_destroy(struct hash_table* ht)
 371 {
 372 #if defined(USE_STATS)
 373     int                         i;
 374     unsigned                    len;
 375     unsigned                    min = 0xffffffff, max = 0, sq = 0;
 376     struct hash_table_elt*      elt;
 377     double                      mean, variance;
 378
 379     for (i = 0; i < ht->num_buckets; i++)
 380     {
 381         for (len = 0, elt = ht->buckets[i]; elt; elt = elt->next) len++;
 382         if (len < min) min = len;
 383         if (len > max) max = len;
 384         sq += len * len;
 385     }
 386     mean = (double)ht->num_elts / ht->num_buckets;
 387     variance = (double)sq / ht->num_buckets - mean * mean;
 388     FIXME("STATS: elts[num:%-4u size:%u mean:%f] buckets[min:%-4u variance:%+f max:%-4u]\n",
 389           ht->num_elts, ht->num_buckets, mean, min, variance, max);
 390 #if 1
 391     for (i = 0; i < ht->num_buckets; i++)
 392     {
 393         for (len = 0, elt = ht->buckets[i]; elt; elt = elt->next) len++;
 394         if (len == max)
 395         {
 396             FIXME("Longuest bucket:\n");
 397             for (elt = ht->buckets[i]; elt; elt = elt->next)
 398                 FIXME("\t%s\n", elt->name);
 399             break;
 400         }
 401
 402     }
 403 #endif
 404 #endif
 405 }
 406
 407 void hash_table_add(struct hash_table* ht, struct hash_table_elt* elt)
 408 {
 409     unsigned                    hash = hash_table_hash(elt->name, ht->num_buckets);
 410     struct hash_table_elt**     p;
 411
 412     /* in some cases, we need to get back the symbols of same name in the order
 413      * in which they've been inserted. So insert new elements at the end of the list.
 414      */
 415     for (p = &ht->buckets[hash]; *p; p = &((*p)->next));
 416     *p = elt;
 417     elt->next = NULL;
 418     ht->num_elts++;
 419 }
 420
 421 void* hash_table_find(const struct hash_table* ht, const char* name)
 422 {
 423     unsigned                    hash = hash_table_hash(name, ht->num_buckets);
 424     struct hash_table_elt*      elt;
 425
 426     for (elt = ht->buckets[hash]; elt; elt = elt->next)
 427         if (!strcmp(name, elt->name)) return elt;
 428     return NULL;
 429 }
 430
 431 void hash_table_iter_init(const struct hash_table* ht,
 432                           struct hash_table_iter* hti, const char* name)
 433 {
 434     hti->ht = ht;
 435     if (name)
 436     {
 437         hti->last = hash_table_hash(name, ht->num_buckets);
 438         hti->index = hti->last - 1;
 439     }
 440     else
 441     {
 442         hti->last = ht->num_buckets - 1;
 443         hti->index = -1;
 444     }
 445     hti->element = NULL;
 446 }
 447
 448 void* hash_table_iter_up(struct hash_table_iter* hti)
 449 {
 450     if (hti->element) hti->element = hti->element->next;
 451     while (!hti->element && hti->index < hti->last)
 452         hti->element = hti->ht->buckets[++hti->index];
 453     return hti->element;
 454 }