mirror of https://gerrit.osmocom.org/asn1c
812 lines
19 KiB
C
812 lines
19 KiB
C
/*
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* Copyright (c) 2002-2005 Lev Walkin <vlm@lionet.info>. All rights reserved.
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* Copyright (c) 2001-2004 Netli, Inc. All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* $Id: genhash.c 447 2005-06-07 06:51:10Z vlm $
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*/
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/*
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* Implementation of a hash data structure.
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* This particular implementation is supposed to be space-efficient
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* particularly in the case of tiny number of hash elements.
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* It also has an aggressive hash buckets expanding technique, which allows
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* to deal with increasing number of elements without a loss of search speed.
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*
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* Generally, one structure of type genhash_t is allocated per hash set.
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* This structure is supposed to hold all information related to the current
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* set, and also holds a tiny number of hash elements, when hash hasn't yet
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* grown up. When the number of elements reaches some point, part of the
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* genhash_t structure is reused to contain the pointers to the actual
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* hash buckets and LRU (Least Recently Used) list's head and tail.
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* Elements which were held inside genhash_t will be moved to the hash buckets.
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*
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* Said above effectively means two modes of operation: TINY and NORMAL.
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* They can be distinguished by examining the h->numbuckets value, which
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* is 0 for TINY and greater for NORMAL mode.
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*
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* In the TINY mode we use a lower part of the genhash_t structure
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* (lower 32 bytes from 64 bytes of genhash_t) to hold up to IH_VALUE (4)
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* key/value pairs.
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*
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* In the NORMAL mode we use the lower part of the genhash_t structure
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* to hold a set of pointers, including a pointer to the hash buckets.
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* We agressively expand hash buckets size when adding new elements
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* to lower the number of key comparisons.
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*/
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#include <sys/types.h>
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#include <stdlib.h>
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#include <string.h>
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#include <assert.h>
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#include <errno.h>
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#include "genhash.h"
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/* 1M entries, 4M RAM */
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#define DEFAULT_MAXIMUM_HASH_BUCKETS_NUMBER (1024 * 1024)
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static int maximum_hash_buckets_number = DEFAULT_MAXIMUM_HASH_BUCKETS_NUMBER;
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/*
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* A single hash element structure which binds a value to its key.
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*/
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typedef struct genhash_el_s {
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unsigned int key_hash; /* Saved hash of the key */
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void *key;
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void *value;
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struct genhash_el_s *hash_next; /* Collision list inside the bucket */
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struct genhash_el_s *hash_prev;
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struct genhash_el_s *lru_prev; /* Per-hash LRU list */
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struct genhash_el_s *lru_next;
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} genhash_el;
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/*
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* A hash structure with buckets etc.
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*/
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struct genhash_s {
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int (*keycmpf) (const void *lkey1, const void *rkey2);
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unsigned int (*keyhashf) (const void *key); /* hash function */
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void (*keydestroyf) (void *key); /* key destructor */
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void (*valuedestroyf) (void *value); /* value destructor */
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int numelements; /* Total number of hash elements */
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int numbuckets; /* 0 means "use _TINY" */
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int lru_limit; /* Must be initialized explicitly */
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genhash_iter_t *iters; /* Active iterators */
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/* 32-byte boundary here */
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union {
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#define IH_VALUES 4 /* Internally held key/value pairs for TINY mode */
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struct _internal_tiny_s {
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void *keys[IH_VALUES];
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void *values[IH_VALUES];
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} _TINY; /* 32-byte structure */
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struct _internal_normal_s {
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genhash_el *lru_head; /* LRU list head */
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genhash_el *lru_tail; /* LRU list tail */
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genhash_el **buckets; /* Hash buckets */
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/* void *unused; */
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} _NORMAL;
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} un;
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#define tiny_keys un._TINY.keys
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#define tiny_values un._TINY.values
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#define lru_head un._NORMAL.lru_head
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#define lru_tail un._NORMAL.lru_tail
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#define buckets un._NORMAL.buckets
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};
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static int
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_genhash_normal_add(genhash_t *h, genhash_el *el, void *key, void *value);
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genhash_t *
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genhash_new(
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int (*keycmpf) (const void *key1, const void *key2),
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unsigned int (*keyhashf) (const void *key),
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void (*keydestroyf) (void *key),
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void (*valuedestroyf) (void *value)
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) {
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genhash_t *h;
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h = (genhash_t *)malloc(sizeof(genhash_t));
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if (!h)
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return NULL;
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memset(h, 0, sizeof(genhash_t));
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genhash_reinit(h, keycmpf, keyhashf, keydestroyf, valuedestroyf);
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return h;
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}
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int
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genhash_reinit(
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genhash_t *h,
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int (*keycmpf) (const void *key1, const void *key2),
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unsigned int (*keyhashf) (const void *key),
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void (*keydestroyf) (void *key),
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void (*valuedestroyf) (void *value)
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) {
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assert(keycmpf && keyhashf);
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h->keycmpf = keycmpf;
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h->keyhashf = keyhashf;
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h->keydestroyf = keydestroyf;
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h->valuedestroyf = valuedestroyf;
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return 0;
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}
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int
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genhash_count(genhash_t *h) {
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if(h) {
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return h->numelements;
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} else {
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return 0;
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}
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}
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static void
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_remove_normal_hash_el(genhash_t *h, genhash_el *el) {
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genhash_iter_t *iter;
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void *kd_arg;
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void *vd_arg;
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/* Remove from the collision list */
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if (el->hash_prev) {
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if((el->hash_prev->hash_next = el->hash_next))
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el->hash_next->hash_prev = el->hash_prev;
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} else {
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if((h->buckets[el->key_hash % h->numbuckets] = el->hash_next))
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el->hash_next->hash_prev = NULL;
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}
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/* Remove from LRU list */
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if(el->lru_prev) {
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if((el->lru_prev->lru_next = el->lru_next))
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el->lru_next->lru_prev = el->lru_prev;
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else
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h->lru_tail = el->lru_prev;
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} else {
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if(h->lru_head == el) {
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if((h->lru_head = el->lru_next) == NULL)
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h->lru_tail = NULL;
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else
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h->lru_head->lru_prev = NULL;
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}
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}
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/* Remember key and value */
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kd_arg = el->key;
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vd_arg = el->value;
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/* Move iterators off the element being deleted */
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for(iter = h->iters; iter; iter = iter->iter_next) {
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assert(iter->hash_ptr == h);
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if(iter->un.location == el) {
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iter->un.location = iter->order_lru_first
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? el->lru_prev : el->lru_next;
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}
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}
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free(el);
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h->numelements--;
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/* Remove key and value */
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if (h->keydestroyf) h->keydestroyf(kd_arg);
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if (h->valuedestroyf) h->valuedestroyf(vd_arg);
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}
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static inline void
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_genhash_normal_el_move2top(genhash_t *h, genhash_el *el) {
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/* Disable sorting if iterators are running */
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if(h->iters) return;
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/* Move to the top of the hash bucket */
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if(el->hash_prev) {
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int bucket = el->key_hash % h->numbuckets;
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/* Remove from the current location */
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if((el->hash_prev->hash_next = el->hash_next))
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el->hash_next->hash_prev = el->hash_prev;
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/* Move to the top of the hash bucket */
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if((el->hash_next = h->buckets[bucket]))
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el->hash_next->hash_prev = el;
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h->buckets[bucket] = el;
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el->hash_prev = NULL;
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}
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/* Move to the top of LRU list */
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if(h->lru_limit && el->lru_prev) {
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/* Remove from current location */
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if((el->lru_prev->lru_next = el->lru_next))
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el->lru_next->lru_prev = el->lru_prev;
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else
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h->lru_tail = el->lru_prev;
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/* Append to the head */
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el->lru_prev = NULL;
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h->lru_head->lru_prev = el;
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el->lru_next = h->lru_head;
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h->lru_head = el;
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}
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}
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static int
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_expand_hash(genhash_t *h) {
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int newbuckets_count;
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genhash_el **newbuckets;
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/*
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* Compute a new number of buckets value.
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*/
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if(h->numbuckets) {
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newbuckets_count = h->numbuckets << 2;
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/* Too big hash table */
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if(newbuckets_count > maximum_hash_buckets_number) {
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if(h->numbuckets < maximum_hash_buckets_number) {
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newbuckets_count = maximum_hash_buckets_number;
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} else {
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/* No need to set errno here. */
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return -1;
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}
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}
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} else {
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/* 8 buckets -> 32 bytes of memory */
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newbuckets_count = IH_VALUES << 1;
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if(newbuckets_count > maximum_hash_buckets_number) {
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if(maximum_hash_buckets_number) {
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newbuckets_count = maximum_hash_buckets_number;
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} else {
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/* Allowed to store only IH_VALUES elements */
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errno = EPERM;
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return -1;
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}
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}
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}
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/*
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* Allocate a new storage for buckets.
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*/
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newbuckets = malloc(newbuckets_count * sizeof(*newbuckets));
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if(newbuckets) {
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memset(newbuckets, 0, newbuckets_count * sizeof(*newbuckets));
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} else {
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return -1;
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}
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if(h->numbuckets) {
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genhash_el *el;
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int bucket;
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/*
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* Rehash elements from old h->buckets to newbuckets.
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* No need to touch LRU pointers and other stuff - it is okay.
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*/
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for(el = h->lru_tail; el; el = el->lru_prev) {
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bucket = el->key_hash % newbuckets_count;
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el->hash_prev = NULL;
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if((el->hash_next = newbuckets[bucket]))
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el->hash_next->hash_prev = el;
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newbuckets[bucket] = el;
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}
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free(h->buckets);
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h->buckets = newbuckets;
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h->numbuckets = newbuckets_count;
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} else {
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/*
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* Moving from inline tiny storage into buckets.
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*/
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genhash_el *els[IH_VALUES] = { NULL };
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struct _internal_tiny_s tiny_substruct;
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int i;
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int saved_numelements;
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int saved_lru_limit;
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genhash_iter_t *iter;
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/* Pre-allocate hash elements (for "undo") */
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for(i = 0; i < h->numelements; i++) {
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els[i] = (genhash_el *)malloc(sizeof(genhash_el));
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if(els[i] == NULL) {
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for(i = 0; i < h->numelements; i++)
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if(els[i])
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free(els[i]);
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free(newbuckets);
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return -1;
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}
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}
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/* Save part of the union */
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tiny_substruct = h->un._TINY;
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/* Re-initialize this part in NORMAL model */
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memset(&h->un._NORMAL, 0, sizeof(h->un._NORMAL));
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/* There was no allocated buckets, when in tiny hash mode. */
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h->buckets = newbuckets;
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h->numbuckets = newbuckets_count;
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saved_numelements = h->numelements;
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saved_lru_limit = h->lru_limit;
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h->numelements = 0;
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h->lru_limit = 0; /* Disable LRU expiration for a while */
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for(i = saved_numelements - 1; i >= 0; --i) {
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/*
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* genhash_normal_add won't fail, if we supply
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* an already allocated genhash_el *.
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*/
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(void)_genhash_normal_add(h, els[i],
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tiny_substruct.keys[i],
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tiny_substruct.values[i]);
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}
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/* Now, scan through iterators and convert them TINY->NORMAL */
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for(iter = h->iters; iter; iter = iter->iter_next) {
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assert(iter->hash_ptr == h);
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if(iter->un.item_number < 0
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|| iter->un.item_number >= saved_numelements) {
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iter->un.location = 0;
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} else {
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iter->un.location = els[iter->un.item_number];
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}
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}
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h->lru_limit = saved_lru_limit;
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}
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return 0;
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}
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/*
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* Won't return with error if el is provided.
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*/
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static int
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_genhash_normal_add(genhash_t *h, genhash_el *el, void *key, void *value) {
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genhash_el **bucket;
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if(el == NULL) {
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el = malloc(sizeof (*el));
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if(el == NULL) {
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/* Errno will be set by malloc() */
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return -1;
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}
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}
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/* Maintain maximum number of entries */
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if(h->lru_limit) {
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while(h->numelements >= h->lru_limit)
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_remove_normal_hash_el(h, h->lru_tail);
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}
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memset(el, 0, sizeof(genhash_el));
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/* Compute the index of the collision list */
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el->key_hash = h->keyhashf(key);
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bucket = &h->buckets[el->key_hash % h->numbuckets];
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el->key = key;
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el->value = value;
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/*
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* Add to the collision list
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*/
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el->hash_prev = NULL;
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if((el->hash_next = *bucket))
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(*bucket)->hash_prev = el;
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*bucket = el;
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/*
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* Add to the LRU list.
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*/
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if(h->lru_head) {
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el->lru_next = h->lru_head;
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el->lru_next->lru_prev = el;
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h->lru_head = el;
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} else {
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h->lru_head = el;
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h->lru_tail = el;
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}
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h->numelements++;
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return 0;
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}
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int
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genhash_add(genhash_t *h, void *key, void *value) {
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if(key == NULL) {
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errno = EINVAL;
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return -1;
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}
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if(h->numbuckets == 0) {
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/* We have a tiny internally-held set of elements */
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if(h->numelements < IH_VALUES) {
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h->tiny_keys[h->numelements] = key;
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h->tiny_values[h->numelements] = value;
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h->numelements++;
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return 0;
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}
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if(_expand_hash(h) == -1)
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return -1;
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} else {
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if((h->numelements / h->numbuckets) > 2)
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(void)_expand_hash(h);
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}
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return _genhash_normal_add(h, NULL, key, value);
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}
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int
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genhash_addunique(genhash_t *h, void *key, void *value) {
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if(genhash_get(h, key)) {
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errno = EEXIST;
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return -1;
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}
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return genhash_add(h, key, value);
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}
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void *
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genhash_get(genhash_t *h, const void *key) {
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if(h->numbuckets) {
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genhash_el *walk;
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int bucket = h->keyhashf(key) % h->numbuckets;
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for(walk = h->buckets[bucket];
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walk; walk = walk->hash_next) {
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if (h->keycmpf(walk->key, key) == 0) {
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_genhash_normal_el_move2top(h, walk);
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return walk->value;
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}
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}
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} else {
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/* TINY mode */
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int i;
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assert(h->numelements <= IH_VALUES);
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for(i = 0; i < h->numelements; i++) {
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if(h->keycmpf(h->tiny_keys[i], key) == 0)
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/* Don't reorder in TINY mode */
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return h->tiny_values[i];
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}
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}
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errno = ESRCH;
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return NULL;
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}
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int
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genhash_del(genhash_t *h, void *key) {
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if(h->numbuckets) {
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/* NORMAL mode */
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genhash_el *walk;
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int bucket;
|
|
|
|
if(h->numelements == 0) {
|
|
errno = ESRCH;
|
|
return -1; /* not found */
|
|
}
|
|
|
|
bucket = h->keyhashf(key) % h->numbuckets;
|
|
|
|
for(walk = h->buckets[bucket]; walk; walk = walk->hash_next)
|
|
if(h->keycmpf(walk->key, key) == 0)
|
|
break;
|
|
|
|
if(walk) {
|
|
_remove_normal_hash_el(h, walk);
|
|
return 0;
|
|
}
|
|
} else {
|
|
/* TINY mode */
|
|
int i;
|
|
|
|
/* Look for matching key */
|
|
for(i = 0; i < h->numelements; i++)
|
|
if(h->keycmpf(h->tiny_keys[i], key) == 0)
|
|
break;
|
|
|
|
if(i < h->numelements) {
|
|
/* Remember values */
|
|
void *kd_arg = h->tiny_keys[i];
|
|
void *vd_arg = h->tiny_values[i];
|
|
|
|
h->numelements--;
|
|
|
|
if(h->iters) {
|
|
/* If iterators are involved, we have to
|
|
* shift elements to maintain iteration order
|
|
* and avoid duplications */
|
|
genhash_iter_t *iter;
|
|
memmove(&h->tiny_keys[i],
|
|
&h->tiny_keys[i+1],
|
|
(h->numelements - i)
|
|
* sizeof(h->tiny_keys[0]));
|
|
memmove(&h->tiny_values[i],
|
|
&h->tiny_values[i+1],
|
|
(h->numelements - i)
|
|
* sizeof(h->tiny_values[0]));
|
|
/* Shift the iterator's indexes */
|
|
for(iter = h->iters; iter;
|
|
iter = iter->iter_next) {
|
|
int in = iter->un.item_number;
|
|
if(iter->order_lru_first) {
|
|
if(in > i)
|
|
iter->un.item_number--;
|
|
} else {
|
|
if(in >= i)
|
|
iter->un.item_number--;
|
|
}
|
|
}
|
|
} else {
|
|
/* Substitute it with the last one */
|
|
/* No harm if overwriting itself */
|
|
h->tiny_keys[i] = h->tiny_keys[h->numelements];
|
|
h->tiny_values[i] = h->tiny_values[h->numelements];
|
|
}
|
|
h->tiny_keys[h->numelements] = 0;
|
|
h->tiny_values[h->numelements] = 0;
|
|
/* Delete for real */
|
|
if(h->keydestroyf) h->keydestroyf(kd_arg);
|
|
if(h->valuedestroyf) h->valuedestroyf(vd_arg);
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
errno = ESRCH;
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* Initialize a hash iterator.
|
|
*/
|
|
int
|
|
genhash_iter_init(genhash_iter_t *iter, genhash_t *h, int reverse_order) {
|
|
|
|
iter->hash_ptr = h;
|
|
iter->iter_prev = 0; /* Add itself to the iterators list */
|
|
iter->iter_next = h->iters;
|
|
h->iters = iter;
|
|
iter->order_lru_first = reverse_order;
|
|
|
|
if(h->numbuckets) {
|
|
/* NORMAL mode */
|
|
if(reverse_order) {
|
|
/* Least recent first order */
|
|
iter->un.location = h->lru_tail;
|
|
} else {
|
|
/* Most recent first order */
|
|
iter->un.location = h->lru_head;
|
|
}
|
|
} else {
|
|
/* TINY mode */
|
|
if(reverse_order) {
|
|
iter->un.item_number = 0;
|
|
} else {
|
|
iter->un.item_number = h->numelements - 1;
|
|
}
|
|
}
|
|
|
|
return h->numelements;
|
|
}
|
|
|
|
int
|
|
genhash_iter(genhash_iter_t *iter, void *key_p, void *val_p) {
|
|
void **key = key_p;
|
|
void **val = val_p;
|
|
genhash_t *h = iter->hash_ptr;
|
|
|
|
if(h->numbuckets) {
|
|
/* NORMAL mode */
|
|
genhash_el *cur_el = iter->un.location;
|
|
if(!cur_el)
|
|
/* Already finished */
|
|
return 0;
|
|
|
|
if(key) *key = cur_el->key;
|
|
if(val) *val = cur_el->value;
|
|
|
|
/* Move pointer to the next hash element */
|
|
iter->un.location = iter->order_lru_first
|
|
? cur_el->lru_prev : cur_el->lru_next;
|
|
} else {
|
|
/* TINY mode */
|
|
if(iter->un.item_number < 0
|
|
|| iter->un.item_number >= h->numelements
|
|
|| h->tiny_keys[iter->un.item_number] == 0)
|
|
return 0;
|
|
|
|
if(key) *key = h->tiny_keys[iter->un.item_number];
|
|
if(val) *val = h->tiny_values[iter->un.item_number];
|
|
|
|
/* Advance to the next element */
|
|
if(iter->order_lru_first)
|
|
iter->un.item_number++;
|
|
else
|
|
iter->un.item_number--;
|
|
}
|
|
|
|
|
|
return 1;
|
|
}
|
|
|
|
void
|
|
genhash_iter_done(genhash_iter_t *iter) {
|
|
assert(iter->hash_ptr->iters);
|
|
/* Remove itself from the iterators list */
|
|
if(iter->iter_next)
|
|
iter->iter_next->iter_prev = iter->iter_prev;
|
|
if(iter->iter_prev)
|
|
iter->iter_prev->iter_next = iter->iter_next;
|
|
else
|
|
iter->hash_ptr->iters = iter->iter_next; /* Shift the head */
|
|
iter->hash_ptr = (void *)0xdeadbeef;
|
|
}
|
|
|
|
int
|
|
genhash_set_lru_limit(genhash_t *h, int value) {
|
|
if(h) {
|
|
int prev_limit = h->lru_limit;
|
|
if(value >= 0)
|
|
h->lru_limit = value;
|
|
return prev_limit;
|
|
} else {
|
|
errno = EINVAL;
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
int
|
|
genhash_set_buckets_limit(int value) {
|
|
int prev_limit = maximum_hash_buckets_number;
|
|
if(value > 0) {
|
|
maximum_hash_buckets_number = value;
|
|
}
|
|
return prev_limit;
|
|
}
|
|
|
|
void
|
|
genhash_destroy(genhash_t *h) {
|
|
if(h) {
|
|
assert(h->iters == 0); /* All iterators MUST be _done(). */
|
|
genhash_empty(h, 1, 1);
|
|
free(h);
|
|
}
|
|
}
|
|
|
|
void
|
|
genhash_empty(genhash_t *h, int freekeys, int freevalues) {
|
|
genhash_iter_t *iter;
|
|
|
|
if(h == NULL) return;
|
|
|
|
/*
|
|
* Don't free what could not be freed.
|
|
*/
|
|
if(h->keydestroyf == NULL) freekeys = 0;
|
|
if(h->valuedestroyf == NULL) freevalues = 0;
|
|
|
|
if(h->numbuckets == 0) {
|
|
while(h->numelements > 0) {
|
|
int n = --h->numelements;
|
|
void *kd_arg = h->tiny_keys[n];
|
|
void *vd_arg = h->tiny_values[n];
|
|
|
|
if (freekeys) h->keydestroyf(kd_arg);
|
|
if (freevalues) h->valuedestroyf(vd_arg);
|
|
}
|
|
} else {
|
|
genhash_el *el, *el_next;
|
|
|
|
for(el = h->lru_head; el; el = el_next) {
|
|
void *kd_arg = el->key;
|
|
void *vd_arg = el->value;
|
|
el_next = el->lru_next;
|
|
free(el);
|
|
|
|
h->numelements --;
|
|
|
|
if (freekeys) h->keydestroyf(kd_arg);
|
|
if (freevalues) h->valuedestroyf(vd_arg);
|
|
}
|
|
free(h->buckets);
|
|
h->numbuckets = 0; /* Move back to TINY model */
|
|
}
|
|
memset(&h->un, 0, sizeof(h->un));
|
|
|
|
/* Invalidate iterators in TINY model */
|
|
for(iter = h->iters; iter; iter = iter->iter_next) {
|
|
assert(iter->hash_ptr == h);
|
|
iter->un.item_number = -1;
|
|
}
|
|
|
|
assert(h->numelements == 0);
|
|
}
|
|
|
|
|
|
/*----- Simple hash and compare functions for common data types ------*/
|
|
|
|
unsigned int
|
|
hashf_int (const void *key) {
|
|
return (*(const int *)key ^ (*(const int *)key >> 16));
|
|
}
|
|
|
|
int
|
|
cmpf_int (const void *key1, const void *key2) {
|
|
return (*(const int *)key1 != *(const int *)key2);
|
|
}
|
|
|
|
unsigned int
|
|
hashf_void (const void *key) {
|
|
return ((int)key ^ ((int)key >> 16));
|
|
}
|
|
|
|
int
|
|
cmpf_void (const void *key1, const void *key2) {
|
|
return (key1 != key2);
|
|
}
|
|
|
|
|
|
/*
|
|
* Phong's linear congruential hash
|
|
*/
|
|
#define dcharhash(h, c) ((h) = 0x63c63cd9*(h) + 0x9c39c33d + (c))
|
|
|
|
unsigned int
|
|
hashf_string(const void *keyarg) {
|
|
register const unsigned char *key;
|
|
register unsigned int h;
|
|
register unsigned char c;
|
|
|
|
key = keyarg;
|
|
for (h = 0; (c = *key++);)
|
|
dcharhash(h, c);
|
|
|
|
return (h);
|
|
}
|
|
|
|
int
|
|
cmpf_string(const void *key1, const void *key2) {
|
|
return strcmp((const char *)key1, (const char *)key2);
|
|
}
|
|
|