实现极小一部分PHP的HASHMAP

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <malloc.h>
#include <math.h>
typedef struct bucket{
    int h;  
    char* key;
    void* pData;
    struct bucket* pNext;
    struct bucket* pLast;
}Bucket;
typedef struct hashtable{
    int size;
    int elementsNum;
    int mask;
    Bucket** arBuckets; //这是一个存放buckets的array 
}HashTable;

/**
 **  这是一个计算HASH值的算法
 **/
int time33(char* arKey,int arlength){
    int h = 0;
    int i;
    for(i=0;i<arlength;i++){
        h = h*33 + (int)*arKey++;
    }
    return h;    
}

/**
 **  初始化一个大小是1的HASHTABLE 
 **/
int _init_hash_table(HashTable** ht){
    *ht = (HashTable*)malloc(sizeof(HashTable));
    (*ht)->size = 1;
    (*ht)->mask = (*ht)->size - 1;    
    (*ht)->elementsNum = 1;
    (*ht)->arBuckets = (Bucket**)malloc(sizeof(Bucket*)*(*ht)->size);
    memset((*ht)->arBuckets,0,sizeof(Bucket*)*(*ht)->size);
    return 1;        
} 

int _hash_link_bucket_to_bucket_head(Bucket** newBucket,Bucket** bucketHead){
    if(*bucketHead==NULL){
        *bucketHead = *newBucket;        
    }else{
        (*newBucket)->pNext = (*bucketHead)->pNext;
        (*newBucket)->pLast = (*bucketHead);
        if((*bucketHead)->pNext != NULL){
            (*bucketHead)->pNext->pLast = *newBucket;    
        }
        (*bucketHead)->pNext = *newBucket;    
    }
    return 1;
}

int _hash_new_bucket(Bucket** newBucket,int hash,char* arkey,void* pData){
    (*newBucket) = (Bucket*)malloc(sizeof(Bucket));
    (*newBucket)->h = hash;
    (*newBucket)->key = arkey;
    (*newBucket)->pData = pData;
    (*newBucket)->pNext = NULL;
    (*newBucket)->pLast = NULL;
    return 1;
}


int _hash_rehash(HashTable* ht){
    int i = 0;
    //由于我没定义pListNext指针，所以只能这样rehash了。 
    for( ; i<ht->size ; i++){
        if(ht->arBuckets[i] != NULL){
            int index = ht->arBuckets[i]->h & ht->mask ;
            if(i != index){
                _hash_link_bucket_to_bucket_head(&ht->arBuckets[i],&ht->arBuckets[index]);
                ht->arBuckets[i] = NULL;    
            }    
        }    
    }
    return 1;        
}

/**
 **  将HASHTABLE的大小扩容1倍 
 **/
int _hash_resize(HashTable* ht){
    if(ht != NULL){
        ht->size = ht->size << 1;
        ht->mask = ht->size - 1; 
        realloc(&ht->arBuckets,sizeof(Bucket*) * ht->size);
        int i;
        for(i=ht->size>>1;i<ht->size;i++){
            ht->arBuckets[i] = NULL;
        }
        //memset(ht->arBuckets[0],NULL,sizeof(Bucket*) * (ht->size >> 1));
        printf("resize:%i\r\n", ht->size);
        _hash_rehash(ht);
        return 1;        
    }
    return 0;
}


/**
 **  往HASHTABLE中添加元素 
 **/
int _hash_add_or_update(HashTable* ht,char* arKey,int arLength,void* pData){
    int h = time33(arKey,arLength);
    int index = h & ht->mask;
    Bucket* p = ht->arBuckets[index]; 
    while(p!=NULL){
        if(strcmp(arKey,p->key)==0){
            //这里应该执行更新操作
            free(p->pData);
            p->pData = pData; 
            return 1;
        }
        p = p->pNext;        
    }
    Bucket* newBucket;
    _hash_new_bucket(&newBucket,h,arKey,pData);
    _hash_link_bucket_to_bucket_head(&newBucket,&ht->arBuckets[index]);
    ht->elementsNum++;
    if(ht->elementsNum = ht->size){
        _hash_resize(ht);
    }
    return 0;
    
}

void* _hash_find(HashTable* ht,char* arKey,int arLength){
    int h = time33(arKey,arLength);
    int index = h & ht->mask;
    Bucket* p = ht->arBuckets[index]; 
    while(p!=NULL){
        if(strcmp(arKey,p->key)==0){
            return p->pData;
        }
        p = p->pNext;
    }
    return 0;
}

int PUT(HashTable* ht,void* key,void* value){
    char* arKey = (char*)key;
    int len = strlen(arKey);
    return _hash_add_or_update(ht,arKey,len,value);    
}

void* GET(HashTable* ht,void* key){
    char* arKey = (char*)key;
    int len = strlen(arKey);
    return _hash_find(ht,arKey,len);
}

int main(){
    printf("%s\r\n","这是一个hashtable的例子");
    HashTable* ht;
    _init_hash_table(&ht);
    PUT(ht,"1","mengjun");
    PUT(ht,"2","aaaaa");
    PUT(ht,"3","fff");
    PUT(ht,"24","eee");
    PUT(ht,"25","ddd");
    printf("%s\r\n",(char*)GET(ht,"1"));
    printf("%s\r\n",(char*)GET(ht,"2"));
    printf("%s\r\n",(char*)GET(ht,"3"));
    printf("%s\r\n",(char*)GET(ht,"24"));
    printf("%s\r\n",(char*)GET(ht,"25"));
    printf("HASHTABLE总共有元素%i个\r\n",ht->elementsNum);
    return 0;
}