htop源码中的Hashtable

来源：互联网发布：java中的md5怎么解密编辑：程序博客网时间：2024/05/22 10:35
这里的Hashtable其实是hashmap，实现的是int型到void*的映射。
Hashtable结构的简单演示如下图：
代码片段如下：
typedef struct HashtableItem {   unsigned int key;   void* value;   struct HashtableItem* next;} HashtableItem;typedef struct Hashtable_ {   int size;   HashtableItem** buckets;   int items;   bool owner;}Hashtable;static HashtableItem* HashtableItem_new(unsigned int key, void* value) {   HashtableItem* this;   this = (HashtableItem*) malloc(sizeof(HashtableItem));   this->key = key;   this->value = value;   this->next = NULL;   return this;}Hashtable* Hashtable_new(int size, bool owner) {   Hashtable* this;   this = (Hashtable*) malloc(sizeof(Hashtable));   this->items = 0;   this->size = size;   this->buckets = (HashtableItem**) calloc(sizeof(HashtableItem*), size);   this->owner = owner;   assert(Hashtable_isConsistent(this));   return this;}void Hashtable_delete(Hashtable* this) {   assert(Hashtable_isConsistent(this));   for (int i = 0; i < this->size; i++) {      HashtableItem* walk = this->buckets[i];      while (walk != NULL) {         if (this->owner)            free(walk->value);         HashtableItem* savedWalk = walk;         walk = savedWalk->next;         free(savedWalk);      }   }   free(this->buckets);   free(this);}void Hashtable_put(Hashtable* this, unsigned int key, void* value) {   unsigned int index = key % this->size;   HashtableItem** bucketPtr = &(this->buckets[index]);   while (true)      if (*bucketPtr == NULL) {         *bucketPtr = HashtableItem_new(key, value);         this->items++;         break;      } else if ((*bucketPtr)->key == key) {         if (this->owner)            free((*bucketPtr)->value);         (*bucketPtr)->value = value;         break;      } else         bucketPtr = &((*bucketPtr)->next);   assert(Hashtable_isConsistent(this));}void* Hashtable_remove(Hashtable* this, unsigned int key) {   unsigned int index = key % this->size;   assert(Hashtable_isConsistent(this));   HashtableItem** bucket;   for (bucket = &(this->buckets[index]); *bucket; bucket = &((*bucket)->next) ) {      if ((*bucket)->key == key) {         void* value = (*bucket)->value;         HashtableItem* next = (*bucket)->next;         free(*bucket);         (*bucket) = next;         this->items--;         if (this->owner) {            free(value);            assert(Hashtable_isConsistent(this));            return NULL;         } else {            assert(Hashtable_isConsistent(this));            return value;         }      }   }   assert(Hashtable_isConsistent(this));   return NULL;}inline void* Hashtable_get(Hashtable* this, unsigned int key) {   unsigned int index = key % this->size;   HashtableItem* bucketPtr = this->buckets[index];   while (true) {      if (bucketPtr == NULL) {         assert(Hashtable_isConsistent(this));         return NULL;      } else if (bucketPtr->key == key) {         assert(Hashtable_isConsistent(this));         return bucketPtr->value;      } else         bucketPtr = bucketPtr->next;   }}void Hashtable_foreach(Hashtable* this, Hashtable_PairFunction f, void* userData) {   assert(Hashtable_isConsistent(this));   for (int i = 0; i < this->size; i++) {      HashtableItem* walk = this->buckets[i];      while (walk != NULL) {         f(walk->key, walk->value, userData);         walk = walk->next;      }   }   assert(Hashtable_isConsistent(this));}
htop源码获取：http://download.csdn.net/detail/u014495327/7142007
0 0