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/* $OpenBSD: hash.c,v 1.3 2016/10/12 15:51:44 millert Exp $ */ |
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/* |
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* Copyright (c) 2008 Joris Vink <joris@openbsd.org> |
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* |
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* Permission to use, copy, modify, and distribute this software for any |
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* purpose with or without fee is hereby granted, provided that the above |
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* copyright notice and this permission notice appear in all copies. |
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* |
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* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES |
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* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF |
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* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR |
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* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
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* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN |
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* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF |
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* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. |
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*/ |
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#include <sys/types.h> |
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#include <sys/queue.h> |
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#include <stdio.h> |
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#include <stdlib.h> |
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#include <string.h> |
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#include "cvs.h" |
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#include "hash.h" |
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#include "xmalloc.h" |
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void |
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hash_table_init(struct hash_table *htable, size_t hsize) |
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{ |
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size_t i; |
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u_int power; |
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if (hsize < MIN_HASH_SIZE) |
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hsize = MIN_HASH_SIZE; |
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if (hsize > MAX_HASH_SIZE) |
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hsize = MAX_HASH_SIZE; |
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if ((hsize & (hsize - 1)) != 0) { |
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for (power = 0; hsize != 0; power++) |
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hsize >>= 1; |
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hsize = 1 << power; |
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} |
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htable->h_table = xcalloc(hsize, sizeof(struct hash_head)); |
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htable->h_size = hsize; |
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for (i = 0; i < htable->h_size; i++) |
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SLIST_INIT(&(htable->h_table[i])); |
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} |
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void |
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hash_table_enter(struct hash_table *htable, struct hash_data *e) |
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{ |
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uint32_t hashv; |
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struct hash_head *tableh; |
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struct hash_table_entry *entry; |
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hashv = hash4(e->h_key, strlen(e->h_key)); |
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tableh = &(htable->h_table[(hashv & (htable->h_size - 1))]); |
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entry = xmalloc(sizeof(*entry)); |
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entry->h_data.h_key = e->h_key; |
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entry->h_data.h_data = e->h_data; |
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SLIST_INSERT_HEAD(tableh, entry, h_list); |
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} |
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struct hash_data * |
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hash_table_find(struct hash_table *htable, const char *key, size_t len) |
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{ |
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uint32_t hashv; |
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struct hash_head *tableh; |
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struct hash_table_entry *entry; |
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hashv = hash4(key, len); |
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tableh = &(htable->h_table[(hashv & (htable->h_size - 1))]); |
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SLIST_FOREACH(entry, tableh, h_list) { |
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if (!strcmp(entry->h_data.h_key, key)) |
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return (&(entry->h_data)); |
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} |
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return (NULL); |
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} |