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Diffstat (limited to 'gcc-4.7/libobjc/hash.c')
-rw-r--r-- | gcc-4.7/libobjc/hash.c | 295 |
1 files changed, 0 insertions, 295 deletions
diff --git a/gcc-4.7/libobjc/hash.c b/gcc-4.7/libobjc/hash.c deleted file mode 100644 index 733fc6501..000000000 --- a/gcc-4.7/libobjc/hash.c +++ /dev/null @@ -1,295 +0,0 @@ -/* Hash tables for Objective C internal structures - Copyright (C) 1993, 1996, 1997, 2004, 2009, 2010 - Free Software Foundation, Inc. - -This file is part of GCC. - -GCC 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. - -GCC 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. - -Under Section 7 of GPL version 3, you are granted additional -permissions described in the GCC Runtime Library Exception, version -3.1, as published by the Free Software Foundation. - -You should have received a copy of the GNU General Public License and -a copy of the GCC Runtime Library Exception along with this program; -see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -<http://www.gnu.org/licenses/>. */ - -#include "objc-private/common.h" -#include <assert.h> /* For assert. */ - -#include "objc/runtime.h" /* For objc_calloc. */ -#include "objc-private/hash.h" - -/* These two macros determine when a hash table is full and - by how much it should be expanded respectively. - - These equations are percentages. */ -#define FULLNESS(cache) \ - ((((cache)->size * 75) / 100) <= (cache)->used) -#define EXPANSION(cache) \ - ((cache)->size * 2) - -cache_ptr -objc_hash_new (unsigned int size, hash_func_type hash_func, - compare_func_type compare_func) -{ - cache_ptr cache; - - /* Pass me a value greater than 0 and a power of 2. */ - assert (size); - assert (! (size & (size - 1))); - - /* Allocate the cache structure. calloc insures its initialization - for default values. */ - cache = (cache_ptr) objc_calloc (1, sizeof (struct cache)); - assert (cache); - - /* Allocate the array of buckets for the cache. calloc initializes - all of the pointers to NULL. */ - cache->node_table - = (node_ptr *) objc_calloc (size, sizeof (node_ptr)); - assert (cache->node_table); - - cache->size = size; - - /* This should work for all processor architectures (?). */ - cache->mask = (size - 1); - - /* Store the hashing function so that codes can be computed. */ - cache->hash_func = hash_func; - - /* Store the function that compares hash keys to determine if they - are equal. */ - cache->compare_func = compare_func; - - return cache; -} - - -void -objc_hash_delete (cache_ptr cache) -{ - node_ptr node; - node_ptr next_node; - unsigned int i; - - /* Purge all key/value pairs from the table. */ - /* Step through the nodes one by one and remove every node WITHOUT - using objc_hash_next. this makes objc_hash_delete much more - efficient. */ - for (i = 0; i < cache->size; i++) - { - if ((node = cache->node_table[i])) - { - /* An entry in the hash table has been found. Now step - through the nodes next in the list and free them. */ - while ((next_node = node->next)) - { - objc_hash_remove (cache,node->key); - node = next_node; - } - objc_hash_remove (cache,node->key); - } - } - - /* Release the array of nodes and the cache itself. */ - objc_free(cache->node_table); - objc_free(cache); -} - - -void -objc_hash_add (cache_ptr *cachep, const void *key, void *value) -{ - size_t indx = (*(*cachep)->hash_func) (*cachep, key); - node_ptr node = (node_ptr) objc_calloc (1, sizeof (struct cache_node)); - - assert (node); - - /* Initialize the new node. */ - node->key = key; - node->value = value; - node->next = (*cachep)->node_table[indx]; - - /* Debugging. Check the list for another key. */ -#ifdef DEBUG - { - node_ptr node1 = (*cachep)->node_table[indx]; - while (node1) - { - assert (node1->key != key); - node1 = node1->next; - } - } -#endif - - /* Install the node as the first element on the list. */ - (*cachep)->node_table[indx] = node; - - /* Bump the number of entries in the cache. */ - ++(*cachep)->used; - - /* Check the hash table's fullness. We're going to expand if it is - above the fullness level. */ - if (FULLNESS (*cachep)) - { - /* The hash table has reached its fullness level. Time to - expand it. - - I'm using a slow method here but is built on other primitive - functions thereby increasing its correctness. */ - node_ptr node1 = NULL; - cache_ptr new = objc_hash_new (EXPANSION (*cachep), - (*cachep)->hash_func, - (*cachep)->compare_func); - - DEBUG_PRINTF ("Expanding cache %#x from %d to %d\n", - (int) *cachep, (*cachep)->size, new->size); - - /* Copy the nodes from the first hash table to the new one. */ - while ((node1 = objc_hash_next (*cachep, node1))) - objc_hash_add (&new, node1->key, node1->value); - - /* Trash the old cache. */ - objc_hash_delete (*cachep); - - /* Return a pointer to the new hash table. */ - *cachep = new; - } -} - -void -objc_hash_remove (cache_ptr cache, const void *key) -{ - size_t indx = (*cache->hash_func) (cache, key); - node_ptr node = cache->node_table[indx]; - - /* We assume there is an entry in the table. Error if it is - not. */ - assert (node); - - /* Special case. First element is the key/value pair to be - removed. */ - if ((*cache->compare_func) (node->key, key)) - { - cache->node_table[indx] = node->next; - objc_free(node); - } - else - { - /* Otherwise, find the hash entry. */ - node_ptr prev = node; - BOOL removed = NO; - do - { - if ((*cache->compare_func) (node->key, key)) - { - prev->next = node->next, removed = YES; - objc_free(node); - } - else - prev = node, node = node->next; - } - while (!removed && node); - assert (removed); - } - - /* Decrement the number of entries in the hash table. */ - --cache->used; -} - - -node_ptr -objc_hash_next (cache_ptr cache, node_ptr node) -{ - /* If the scan is being started then reset the last node visitied - pointer and bucket index. */ - if (!node) - cache->last_bucket = 0; - - /* If there is a node visited last then check for another entry in - the same bucket. Otherwise step to the next bucket. */ - if (node) - { - if (node->next) - { - /* There is a node which follows the last node returned. - Step to that node and retun it. */ - return node->next; - } - else - ++cache->last_bucket; - } - - /* If the list isn't exhausted then search the buckets for other - nodes. */ - if (cache->last_bucket < cache->size) - { - /* Scan the remainder of the buckets looking for an entry at - the head of the list. Return the first item found. */ - while (cache->last_bucket < cache->size) - if (cache->node_table[cache->last_bucket]) - return cache->node_table[cache->last_bucket]; - else - ++cache->last_bucket; - - /* No further nodes were found in the hash table. */ - return NULL; - } - else - return NULL; -} - - -/* Given KEY, return corresponding value for it in CACHE. Return NULL - if the KEY is not recorded. */ -void * -objc_hash_value_for_key (cache_ptr cache, const void *key) -{ - node_ptr node = cache->node_table[(*cache->hash_func) (cache, key)]; - void *retval = NULL; - - if (node) - do - { - if ((*cache->compare_func) (node->key, key)) - { - retval = node->value; - break; - } - else - node = node->next; - } - while (! retval && node); - - return retval; -} - -/* Given KEY, return YES if it exists in the CACHE. Return NO if it - does not */ -BOOL -objc_hash_is_key_in_hash (cache_ptr cache, const void *key) -{ - node_ptr node = cache->node_table[(*cache->hash_func) (cache, key)]; - - if (node) - do - { - if ((*cache->compare_func)(node->key, key)) - return YES; - else - node = node->next; - } - while (node); - - return NO; -} |