???
git-svn-id: http://svn.eurecom.fr/openair4G/trunk@4660 818b1a75-f10b-46b9-bf7c-635c3b92a50f
This commit is contained in:
+286
@@ -0,0 +1,286 @@
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/* from: http://en.literateprograms.org/Hash_table_%28C%29#chunk%20def:node
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*
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*/
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#include <string.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include "hashtable.h"
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//-------------------------------------------------------------------------------------------------------------------------------
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char* hashtble_rc_code2string(hashtable_rc_t rcP)
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//-------------------------------------------------------------------------------------------------------------------------------
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{
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switch (rcP) {
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case HASH_TABLE_OK: return "HASH_TABLE_OK";break;
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case HASH_TABLE_INSERT_OVERWRITTEN_DATA: return "HASH_TABLE_INSERT_OVERWRITTEN_DATA";break;
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case HASH_TABLE_KEY_NOT_EXISTS: return "HASH_TABLE_KEY_NOT_EXISTS";break;
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case HASH_TABLE_KEY_ALREADY_EXISTS: return "HASH_TABLE_KEY_ALREADY_EXISTS";break;
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case HASH_TABLE_BAD_PARAMETER_HASHTABLE: return "HASH_TABLE_BAD_PARAMETER_HASHTABLE";break;
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default: return "UNKNOWN hashtable_rc_t";
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}
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}
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//-------------------------------------------------------------------------------------------------------------------------------
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/*
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* free int function
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* hash_free_int_func() is used when this hashtable is used to store int values as data (pointer = value).
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*/
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void hash_free_int_func(void* memoryP){}
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//-------------------------------------------------------------------------------------------------------------------------------
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/*
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* Default hash function
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* def_hashfunc() is the default used by hashtable_create() when the user didn't specify one.
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* This is a simple/naive hash function which adds the key's ASCII char values. It will probably generate lots of collisions on large hash tables.
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*/
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static hash_size_t def_hashfunc(const uint64_t keyP)
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{
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return (hash_size_t)keyP;
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}
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//-------------------------------------------------------------------------------------------------------------------------------
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/*
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* Initialisation
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* hashtable_create() sets up the initial structure of the hash table. The user specified size will be allocated and initialized to NULL.
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* The user can also specify a hash function. If the hashfunc argument is NULL, a default hash function is used.
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* If an error occurred, NULL is returned. All other values in the returned hash_table_t pointer should be released with hashtable_destroy().
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*/
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hash_table_t *hashtable_create(hash_size_t sizeP, hash_size_t (*hashfuncP)(const uint64_t ), void (*freefuncP)(void*))
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{
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hash_table_t *hashtbl;
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if(!(hashtbl=malloc(sizeof(hash_table_t)))) return NULL;
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if(!(hashtbl->nodes=calloc(sizeP, sizeof(hash_node_t*)))) {
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free(hashtbl);
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return NULL;
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}
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hashtbl->size=sizeP;
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if(hashfuncP) hashtbl->hashfunc=hashfuncP;
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else hashtbl->hashfunc=def_hashfunc;
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if(freefuncP) hashtbl->freefunc=freefuncP;
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else hashtbl->freefunc=free;
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return hashtbl;
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}
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//-------------------------------------------------------------------------------------------------------------------------------
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/*
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* Cleanup
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* The hashtable_destroy() walks through the linked lists for each possible hash value, and releases the elements. It also releases the nodes array and the hash_table_t.
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*/
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hashtable_rc_t hashtable_destroy(hash_table_t *hashtblP)
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{
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hash_size_t n;
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hash_node_t *node, *oldnode;
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if (hashtblP == NULL) {
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return HASH_TABLE_BAD_PARAMETER_HASHTABLE;
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}
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for(n=0; n<hashtblP->size; ++n) {
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node=hashtblP->nodes[n];
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while(node) {
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oldnode=node;
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node=node->next;
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if (oldnode->data) {
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hashtblP->freefunc(oldnode->data);
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}
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free(oldnode);
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}
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}
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free(hashtblP->nodes);
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free(hashtblP);
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return HASH_TABLE_OK;
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}
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//-------------------------------------------------------------------------------------------------------------------------------
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hashtable_rc_t hashtable_is_key_exists (hash_table_t *hashtblP, const uint64_t keyP)
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//-------------------------------------------------------------------------------------------------------------------------------
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{
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hash_node_t *node;
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hash_size_t hash;
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if (hashtblP == NULL) {
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return HASH_TABLE_BAD_PARAMETER_HASHTABLE;
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}
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hash=hashtblP->hashfunc(keyP)%hashtblP->size;
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node=hashtblP->nodes[hash];
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while(node) {
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if(node->key == keyP) {
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return HASH_TABLE_OK;
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}
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node=node->next;
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}
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return HASH_TABLE_KEY_NOT_EXISTS;
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}
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//-------------------------------------------------------------------------------------------------------------------------------
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hashtable_rc_t hashtable_apply_funct_on_elements (hash_table_t *hashtblP, void functP(uint64_t keyP, void* dataP, void* parameterP), void* parameterP)
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//-------------------------------------------------------------------------------------------------------------------------------
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{
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hash_node_t *node = NULL;
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unsigned int i = 0;
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unsigned int num_elements = 0;
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if (hashtblP == NULL) {
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return HASH_TABLE_BAD_PARAMETER_HASHTABLE;
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}
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while ((num_elements < hashtblP->num_elements) && (i < hashtblP->size)) {
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if (hashtblP->nodes[i] != NULL) {
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node=hashtblP->nodes[i];
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while(node) {
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num_elements += 1;
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functP(node->key, node->data, parameterP);
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node=node->next;
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}
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}
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i += 1;
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}
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return HASH_TABLE_OK;
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}
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//-------------------------------------------------------------------------------------------------------------------------------
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/*
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* Adding a new element
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* To make sure the hash value is not bigger than size, the result of the user provided hash function is used modulo size.
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*/
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hashtable_rc_t hashtable_insert(hash_table_t *hashtblP, const uint64_t keyP, void *dataP)
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{
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hash_node_t *node;
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hash_size_t hash;
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if (hashtblP == NULL) {
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return HASH_TABLE_BAD_PARAMETER_HASHTABLE;
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}
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hash=hashtblP->hashfunc(keyP)%hashtblP->size;
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node=hashtblP->nodes[hash];
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while(node) {
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if(node->key == keyP) {
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if (node->data) {
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hashtblP->freefunc(node->data);
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}
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node->data=dataP;
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return HASH_TABLE_INSERT_OVERWRITTEN_DATA;
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}
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node=node->next;
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}
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if(!(node=malloc(sizeof(hash_node_t)))) return -1;
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node->key=keyP;
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node->data=dataP;
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if (hashtblP->nodes[hash]) {
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node->next=hashtblP->nodes[hash];
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} else {
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node->next = NULL;
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}
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hashtblP->nodes[hash]=node;
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hashtblP->num_elements += 1;
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return HASH_TABLE_OK;
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}
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//-------------------------------------------------------------------------------------------------------------------------------
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/*
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* To remove an element from the hash table, we just search for it in the linked list for that hash value,
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* and remove it if it is found. If it was not found, it is an error and -1 is returned.
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*/
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hashtable_rc_t hashtable_remove(hash_table_t *hashtblP, const uint64_t keyP)
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{
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hash_node_t *node, *prevnode=NULL;
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hash_size_t hash;
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if (hashtblP == NULL) {
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return HASH_TABLE_BAD_PARAMETER_HASHTABLE;
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}
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hash=hashtblP->hashfunc(keyP)%hashtblP->size;
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node=hashtblP->nodes[hash];
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while(node) {
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if(node->key != keyP) {
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if(prevnode) prevnode->next=node->next;
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else hashtblP->nodes[hash]=node->next;
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if (node->data) {
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hashtblP->freefunc(node->data);
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}
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free(node);
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hashtblP->num_elements -= 1;
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return HASH_TABLE_OK;
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}
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prevnode=node;
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node=node->next;
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}
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return HASH_TABLE_KEY_NOT_EXISTS;
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}
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//-------------------------------------------------------------------------------------------------------------------------------
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/*
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* Searching for an element is easy. We just search through the linked list for the corresponding hash value.
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* NULL is returned if we didn't find it.
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*/
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hashtable_rc_t hashtable_get(hash_table_t *hashtblP, const uint64_t keyP, void** dataP)
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{
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hash_node_t *node;
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hash_size_t hash;
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if (hashtblP == NULL) {
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*dataP = NULL;
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return HASH_TABLE_BAD_PARAMETER_HASHTABLE;
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}
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hash=hashtblP->hashfunc(keyP)%hashtblP->size;
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/* fprintf(stderr, "hashtable_get() key=%s, hash=%d\n", key, hash);*/
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node=hashtblP->nodes[hash];
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while(node) {
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if(node->key == keyP) {
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*dataP = node->data;
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return HASH_TABLE_OK;
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}
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node=node->next;
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}
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*dataP = NULL;
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return HASH_TABLE_KEY_NOT_EXISTS;
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}
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//-------------------------------------------------------------------------------------------------------------------------------
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/*
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* Resizing
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* The number of elements in a hash table is not always known when creating the table.
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* If the number of elements grows too large, it will seriously reduce the performance of most hash table operations.
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* If the number of elements are reduced, the hash table will waste memory. That is why we provide a function for resizing the table.
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* Resizing a hash table is not as easy as a realloc(). All hash values must be recalculated and each element must be inserted into its new position.
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* We create a temporary hash_table_t object (newtbl) to be used while building the new hashes.
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* This allows us to reuse hashtable_insert() and hashtable_remove(), when moving the elements to the new table.
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* After that, we can just free the old table and copy the elements from newtbl to hashtbl.
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*/
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hashtable_rc_t hashtable_resize(hash_table_t *hashtblP, hash_size_t sizeP)
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{
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hash_table_t newtbl;
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hash_size_t n;
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hash_node_t *node,*next;
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if (hashtblP == NULL) {
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return HASH_TABLE_BAD_PARAMETER_HASHTABLE;
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}
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newtbl.size = sizeP;
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newtbl.hashfunc = hashtblP->hashfunc;
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if(!(newtbl.nodes=calloc(sizeP, sizeof(hash_node_t*)))) return -1;
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for(n=0; n<hashtblP->size; ++n) {
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for(node=hashtblP->nodes[n]; node; node=next) {
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next = node->next;
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hashtable_insert(&newtbl, node->key, node->data);
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// Lionel GAUTHIER: BAD CODE TO BE REWRITTEN
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hashtable_remove(hashtblP, node->key);
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}
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}
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free(hashtblP->nodes);
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hashtblP->size=newtbl.size;
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hashtblP->nodes=newtbl.nodes;
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return HASH_TABLE_OK;
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}
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+47
@@ -0,0 +1,47 @@
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#ifndef _UTILS_COLLECTION_HASH_TABLE_H_
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#define _UTILS_COLLECTION_HASH_TABLE_H_
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#include<stdlib.h>
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#include <stdint.h>
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#include <stddef.h>
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typedef size_t hash_size_t;
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typedef enum hashtable_return_code_e {
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HASH_TABLE_OK = 0,
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HASH_TABLE_INSERT_OVERWRITTEN_DATA = 1,
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HASH_TABLE_KEY_NOT_EXISTS = 2,
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HASH_TABLE_KEY_ALREADY_EXISTS = 3,
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HASH_TABLE_BAD_PARAMETER_HASHTABLE = 4,
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HASH_TABLE_CODE_MAX
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} hashtable_rc_t;
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typedef struct hash_node_s {
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uint64_t key;
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void *data;
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struct hash_node_s *next;
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} hash_node_t;
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typedef struct hash_table_s {
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hash_size_t size;
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hash_size_t num_elements;
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struct hash_node_s **nodes;
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hash_size_t (*hashfunc)(const uint64_t);
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void (*freefunc)(void*);
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} hash_table_t;
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char* hashtble_rc_code2string(hashtable_rc_t rcP);
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void hash_free_int_func(void* memoryP);
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hash_table_t *hashtable_create (hash_size_t size, hash_size_t (*hashfunc)(const uint64_t ), void (*freefunc)(void*));
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hashtable_rc_t hashtable_destroy(hash_table_t *hashtbl);
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hashtable_rc_t hashtable_is_key_exists (hash_table_t *hashtbl, const uint64_t key);
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hashtable_rc_t hashtable_apply_funct_on_elements (hash_table_t *hashtblP, void funct(uint64_t keyP, void* dataP, void* parameterP), void* parameterP);
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hashtable_rc_t hashtable_insert (hash_table_t *hashtbl, const uint64_t key, void *data);
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hashtable_rc_t hashtable_remove (hash_table_t *hashtbl, const uint64_t key);
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hashtable_rc_t hashtable_get (hash_table_t *hashtbl, const uint64_t key, void **dataP);
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hashtable_rc_t hashtable_resize (hash_table_t *hashtbl, hash_size_t size);
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#endif
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+238
@@ -0,0 +1,238 @@
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/* from: http://en.literateprograms.org/Hash_table_%28C%29#chunk%20def:node
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*
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*/
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#include <string.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include "obj_hashtable.h"
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//-------------------------------------------------------------------------------------------------------------------------------
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/*
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* Default hash function
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* def_hashfunc() is the default used by hashtable_create() when the user didn't specify one.
|
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* This is a simple/naive hash function which adds the key's ASCII char values. It will probably generate lots of collisions on large hash tables.
|
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*/
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static hash_size_t def_hashfunc(const void *keyP, int key_sizeP)
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{
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hash_size_t hash=0;
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while(key_sizeP) hash^=((unsigned char*)keyP)[key_sizeP --];
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return hash;
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}
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//-------------------------------------------------------------------------------------------------------------------------------
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/*
|
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* Initialisation
|
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* hashtable_create() sets up the initial structure of the hash table. The user specified size will be allocated and initialized to NULL.
|
||||
* The user can also specify a hash function. If the hashfunc argument is NULL, a default hash function is used.
|
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* If an error occurred, NULL is returned. All other values in the returned obj_hash_table_t pointer should be released with hashtable_destroy().
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*/
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obj_hash_table_t *obj_hashtable_create(hash_size_t sizeP, hash_size_t (*hashfuncP)(const void*, int ), void (*freekeyfuncP)(void*), void (*freedatafuncP)(void*))
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{
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obj_hash_table_t *hashtbl;
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if(!(hashtbl=malloc(sizeof(obj_hash_table_t)))) return NULL;
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if(!(hashtbl->nodes=calloc(sizeP, sizeof(obj_hash_node_t*)))) {
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free(hashtbl);
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return NULL;
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}
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hashtbl->size=sizeP;
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if(hashfuncP) hashtbl->hashfunc=hashfuncP;
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else hashtbl->hashfunc=def_hashfunc;
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if(freekeyfuncP) hashtbl->freekeyfunc=freekeyfuncP;
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else hashtbl->freekeyfunc=free;
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if(freedatafuncP) hashtbl->freedatafunc=freedatafuncP;
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else hashtbl->freedatafunc=free;
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||||
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return hashtbl;
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||||
}
|
||||
//-------------------------------------------------------------------------------------------------------------------------------
|
||||
/*
|
||||
* Cleanup
|
||||
* The hashtable_destroy() walks through the linked lists for each possible hash value, and releases the elements. It also releases the nodes array and the obj_hash_table_t.
|
||||
*/
|
||||
hashtable_rc_t obj_hashtable_destroy(obj_hash_table_t *hashtblP)
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{
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hash_size_t n;
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obj_hash_node_t *node, *oldnode;
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for(n=0; n<hashtblP->size; ++n) {
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node=hashtblP->nodes[n];
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while(node) {
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oldnode=node;
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node=node->next;
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hashtblP->freekeyfunc(oldnode->key);
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hashtblP->freedatafunc(oldnode->data);
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free(oldnode);
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}
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}
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free(hashtblP->nodes);
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free(hashtblP);
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return HASH_TABLE_OK;
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||||
}
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||||
//-------------------------------------------------------------------------------------------------------------------------------
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||||
hashtable_rc_t obj_hashtable_is_key_exists (obj_hash_table_t *hashtblP, void* keyP, int key_sizeP)
|
||||
//-------------------------------------------------------------------------------------------------------------------------------
|
||||
{
|
||||
obj_hash_node_t *node;
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||||
hash_size_t hash;
|
||||
|
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if (hashtblP == NULL) {
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||||
return HASH_TABLE_BAD_PARAMETER_HASHTABLE;
|
||||
}
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||||
hash=hashtblP->hashfunc(keyP, key_sizeP)%hashtblP->size;
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||||
node=hashtblP->nodes[hash];
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||||
while(node) {
|
||||
if(node->key == keyP) {
|
||||
return HASH_TABLE_OK;
|
||||
}
|
||||
node=node->next;
|
||||
}
|
||||
return HASH_TABLE_KEY_NOT_EXISTS;
|
||||
}
|
||||
//-------------------------------------------------------------------------------------------------------------------------------
|
||||
/*
|
||||
* Adding a new element
|
||||
* To make sure the hash value is not bigger than size, the result of the user provided hash function is used modulo size.
|
||||
*/
|
||||
hashtable_rc_t obj_hashtable_insert(obj_hash_table_t *hashtblP, void* keyP, int key_sizeP, void *dataP)
|
||||
{
|
||||
obj_hash_node_t *node;
|
||||
hash_size_t hash;
|
||||
|
||||
if (hashtblP == NULL) {
|
||||
return HASH_TABLE_BAD_PARAMETER_HASHTABLE;
|
||||
}
|
||||
hash=hashtblP->hashfunc(keyP, key_sizeP)%hashtblP->size;
|
||||
node=hashtblP->nodes[hash];
|
||||
while(node) {
|
||||
if(node->key == keyP) {
|
||||
if (node->data) {
|
||||
hashtblP->freedatafunc(node->data);
|
||||
}
|
||||
node->data=dataP;
|
||||
// waste of memory here (keyP is lost) we should free it now
|
||||
return HASH_TABLE_INSERT_OVERWRITTEN_DATA;
|
||||
}
|
||||
node=node->next;
|
||||
}
|
||||
if(!(node=malloc(sizeof(obj_hash_node_t)))) return -1;
|
||||
node->key=keyP;
|
||||
node->data=dataP;
|
||||
if (hashtblP->nodes[hash]) {
|
||||
node->next=hashtblP->nodes[hash];
|
||||
} else {
|
||||
node->next = NULL;
|
||||
}
|
||||
hashtblP->nodes[hash]=node;
|
||||
return HASH_TABLE_OK;
|
||||
}
|
||||
//-------------------------------------------------------------------------------------------------------------------------------
|
||||
/*
|
||||
* To remove an element from the hash table, we just search for it in the linked list for that hash value,
|
||||
* and remove it if it is found. If it was not found, it is an error and -1 is returned.
|
||||
*/
|
||||
hashtable_rc_t obj_hashtable_remove(obj_hash_table_t *hashtblP, const void* keyP, int key_sizeP)
|
||||
{
|
||||
obj_hash_node_t *node, *prevnode=NULL;
|
||||
hash_size_t hash;
|
||||
|
||||
if (hashtblP == NULL) {
|
||||
return HASH_TABLE_BAD_PARAMETER_HASHTABLE;
|
||||
}
|
||||
|
||||
hash=hashtblP->hashfunc(keyP, key_sizeP)%hashtblP->size;
|
||||
node=hashtblP->nodes[hash];
|
||||
while(node) {
|
||||
if(node->key == keyP) {
|
||||
if(prevnode) {
|
||||
prevnode->next=node->next;
|
||||
} else {
|
||||
hashtblP->nodes[hash]=node->next;
|
||||
}
|
||||
hashtblP->freekeyfunc(node->key);
|
||||
hashtblP->freedatafunc(node->data);
|
||||
free(node);
|
||||
return HASH_TABLE_OK;
|
||||
}
|
||||
prevnode=node;
|
||||
node=node->next;
|
||||
}
|
||||
return HASH_TABLE_KEY_NOT_EXISTS;
|
||||
}
|
||||
//-------------------------------------------------------------------------------------------------------------------------------
|
||||
/*
|
||||
* Searching for an element is easy. We just search through the linked list for the corresponding hash value.
|
||||
* NULL is returned if we didn't find it.
|
||||
*/
|
||||
hashtable_rc_t obj_hashtable_get(obj_hash_table_t *hashtblP, const void* keyP, int key_sizeP, void** dataP)
|
||||
{
|
||||
obj_hash_node_t *node;
|
||||
hash_size_t hash;
|
||||
|
||||
if (hashtblP == NULL) {
|
||||
*dataP = NULL;
|
||||
return HASH_TABLE_BAD_PARAMETER_HASHTABLE;
|
||||
}
|
||||
hash=hashtblP->hashfunc(keyP, key_sizeP)%hashtblP->size;
|
||||
node=hashtblP->nodes[hash];
|
||||
while(node) {
|
||||
if(node->key == keyP) {
|
||||
*dataP = node->data;
|
||||
return HASH_TABLE_OK;
|
||||
}
|
||||
node=node->next;
|
||||
}
|
||||
*dataP = NULL;
|
||||
return HASH_TABLE_KEY_NOT_EXISTS;
|
||||
}
|
||||
//-------------------------------------------------------------------------------------------------------------------------------
|
||||
/*
|
||||
* Resizing
|
||||
* The number of elements in a hash table is not always known when creating the table.
|
||||
* If the number of elements grows too large, it will seriously reduce the performance of most hash table operations.
|
||||
* If the number of elements are reduced, the hash table will waste memory. That is why we provide a function for resizing the table.
|
||||
* Resizing a hash table is not as easy as a realloc(). All hash values must be recalculated and each element must be inserted into its new position.
|
||||
* We create a temporary obj_hash_table_t object (newtbl) to be used while building the new hashes.
|
||||
* This allows us to reuse hashtable_insert() and hashtable_remove(), when moving the elements to the new table.
|
||||
* After that, we can just free the old table and copy the elements from newtbl to hashtbl.
|
||||
*/
|
||||
hashtable_rc_t obj_hashtable_resize(obj_hash_table_t *hashtblP, hash_size_t sizeP)
|
||||
{
|
||||
obj_hash_table_t newtbl;
|
||||
hash_size_t n;
|
||||
obj_hash_node_t *node,*next;
|
||||
|
||||
if (hashtblP == NULL) {
|
||||
return HASH_TABLE_BAD_PARAMETER_HASHTABLE;
|
||||
}
|
||||
|
||||
newtbl.size = sizeP;
|
||||
newtbl.hashfunc = hashtblP->hashfunc;
|
||||
|
||||
if(!(newtbl.nodes=calloc(sizeP, sizeof(obj_hash_node_t*)))) return -1;
|
||||
|
||||
for(n=0; n<hashtblP->size; ++n) {
|
||||
for(node=hashtblP->nodes[n]; node; node=next) {
|
||||
next = node->next;
|
||||
obj_hashtable_insert(&newtbl, node->key, node->key_size, node->data);
|
||||
//WARNING Lionel GAUTHIER: BAD CODE TO BE REWRITTEN
|
||||
obj_hashtable_remove(hashtblP, node->key, node->key_size);
|
||||
}
|
||||
}
|
||||
|
||||
free(hashtblP->nodes);
|
||||
hashtblP->size=newtbl.size;
|
||||
hashtblP->nodes=newtbl.nodes;
|
||||
|
||||
return HASH_TABLE_OK;
|
||||
}
|
||||
|
||||
|
||||
|
||||
+39
@@ -0,0 +1,39 @@
|
||||
#ifndef _OBJ_HASH_TABLE_H_
|
||||
#define _OBJ_HASH_TABLE_H_
|
||||
#include<stdlib.h>
|
||||
#include <stdint.h>
|
||||
#include <stddef.h>
|
||||
|
||||
#include "hashtable.h"
|
||||
|
||||
typedef size_t hash_size_t;
|
||||
|
||||
|
||||
typedef struct obj_hash_node_s {
|
||||
int key_size;
|
||||
void *key;
|
||||
void *data;
|
||||
struct obj_hash_node_s *next;
|
||||
} obj_hash_node_t;
|
||||
|
||||
typedef struct obj_hash_table_s {
|
||||
hash_size_t size;
|
||||
hash_size_t num_elements;
|
||||
struct obj_hash_node_s **nodes;
|
||||
hash_size_t (*hashfunc)(const void*, int);
|
||||
void (*freekeyfunc)(void*);
|
||||
void (*freedatafunc)(void*);
|
||||
} obj_hash_table_t;
|
||||
|
||||
obj_hash_table_t *obj_hashtable_create (hash_size_t size, hash_size_t (*hashfunc)(const void*, int ), void (*freekeyfunc)(void*), void (*freedatafunc)(void*));
|
||||
hashtable_rc_t obj_hashtable_destroy(obj_hash_table_t *hashtblP);
|
||||
hashtable_rc_t obj_hashtable_is_key_exists (obj_hash_table_t *hashtblP, void* keyP, int key_sizeP);
|
||||
hashtable_rc_t obj_hashtable_insert (obj_hash_table_t *hashtblP, void* keyP, int key_sizeP, void *dataP);
|
||||
hashtable_rc_t obj_hashtable_remove (obj_hash_table_t *hashtblP, const void* keyP, int key_sizeP);
|
||||
hashtable_rc_t obj_hashtable_get (obj_hash_table_t *hashtblP, const void* keyP, int key_sizeP, void ** dataP);
|
||||
hashtable_rc_t obj_hashtable_resize (obj_hash_table_t *hashtblP, hash_size_t sizeP);
|
||||
|
||||
|
||||
|
||||
#endif
|
||||
|
||||
Reference in New Issue
Block a user