在HashTable中，用到了DList来解决冲突，我们不用重新实现其内部的DList，只需将已经实现的双向链表DList组合到HashTable中使用即可。下面给出工程的全部代码：

就不再解释其中每个文件干嘛的了，我懂的。 依次来看看：

1. Makefile

-D name: Predefine name as a macro. (man gcc可以看到)

2. typedef.h

#include <stdio.h>
#include <assert.h>
#include <stdlib.h>#ifndef TYPEDEF_H
#define TYPEDEF_Htypedef enum _Ret
{RET_OK,RET_OOM,RET_STOP,RET_INVALID_PARAMS,RET_FAIL
}Ret;typedef void     (*DataDestroyFunc)(void* ctx, void* data);
typedef int      (*DataCompareFunc)(void* ctx, void* data);
typedef Ret      (*DataVisitFunc)(void* ctx, void* data);
typedef int       (*DataHashFunc)(void* data);#ifdef __cplusplus
#define DECLS_BEGIN extern "C" {
#define DECLS_END   }
#else
#define DECLS_BEGIN
#define DECLS_END
#endif/*__cplusplus*/#define return_if_fail(p) if(!(p)) \{printf("%s:%d Warning: "#p" failed.\n", \__func__, __LINE__); return;}
#define return_val_if_fail(p, ret) if(!(p)) \{printf("%s:%d Warning: "#p" failed.\n",\__func__, __LINE__); return (ret);}#define SAFE_FREE(p) if(p != NULL) {free(p); p = NULL;}typedef Ret (*SortFunc)(void** array, size_t nr, DataCompareFunc cmp);#endif/*TYPEDEF_H*/

3. hash_table.h

#include <stdio.h>
#include "typedef.h"#ifndef HASH_TABLE_H
#define HASH_TABLE_HDECLS_BEGINstruct _HashTable;
typedef struct _HashTable HashTable;HashTable* hash_table_create(DataDestroyFunc data_destroy, void* ctx, DataHashFunc hash, int slot_nr);size_t   hash_table_length(HashTable* thiz);
Ret      hash_table_insert(HashTable* thiz, void* data);
Ret      hash_table_delete(HashTable* thiz, DataCompareFunc cmp, void* data);
Ret      hash_table_find(HashTable* thiz, DataCompareFunc cmp, void* data, void** ret_data);
Ret      hash_table_foreach(HashTable* thiz, DataVisitFunc visit, void* ctx);void hash_table_destroy(HashTable* thiz);DECLS_END#endif/*HASH_TABLE*/

4.hash_table.c

#include "dlist.h"
#include "hash_table.h"struct _HashTable
{DataHashFunc    hash;DList**         slots;size_t          slot_nr;DataDestroyFunc data_destroy;void*           data_destroy_ctx;
};HashTable* hash_table_create(DataDestroyFunc data_destroy, void* ctx, DataHashFunc hash, int slot_nr)
{HashTable* thiz = NULL;return_val_if_fail(hash != NULL && slot_nr > 1, NULL);thiz = (HashTable*)malloc(sizeof(HashTable));if(thiz != NULL){thiz->hash = hash;thiz->slot_nr  = slot_nr;thiz->data_destroy_ctx = ctx;thiz->data_destroy = data_destroy;if((thiz->slots = (DList**)calloc(sizeof(DList*)*slot_nr, 1)) == NULL){free(thiz);thiz = NULL;}}return thiz;
}Ret      hash_table_insert(HashTable* thiz, void* data)
{size_t index = 0;return_val_if_fail(thiz != NULL, RET_INVALID_PARAMS);index = thiz->hash(data)%thiz->slot_nr;if(thiz->slots[index] == NULL){thiz->slots[index] = dlist_create(thiz->data_destroy, thiz->data_destroy_ctx);}return dlist_prepend(thiz->slots[index], data);
}Ret      hash_table_delete(HashTable* thiz, DataCompareFunc cmp, void* data)
{int index = 0;DList* dlist = NULL;return_val_if_fail(thiz != NULL && cmp != NULL, RET_INVALID_PARAMS);index = thiz->hash(data)%thiz->slot_nr;dlist = thiz->slots[index];if(dlist != NULL){index = dlist_find(dlist, cmp, data);return dlist_delete(dlist, index);}return RET_FAIL;
}size_t   hash_table_length(HashTable* thiz)
{size_t i = 0;size_t nr = 0;return_val_if_fail(thiz != NULL, 0);for(i = 0; i < thiz->slot_nr; i++){if(thiz->slots[i] != NULL){nr += dlist_length(thiz->slots[i]);}}return nr;
}Ret    hash_table_find(HashTable* thiz, DataCompareFunc cmp, void* data, void** ret_data)
{int index = 0;DList* dlist = NULL;return_val_if_fail(thiz != NULL && cmp != NULL && ret_data != NULL, RET_INVALID_PARAMS);index = thiz->hash(data)%thiz->slot_nr;dlist = thiz->slots[index];if(dlist != NULL){index = dlist_find(dlist, cmp, data);return dlist_get_by_index(dlist, index, ret_data);}return RET_FAIL;
}Ret      hash_table_foreach(HashTable* thiz, DataVisitFunc visit, void* ctx)
{size_t i = 0;return_val_if_fail(thiz != NULL && visit != NULL, RET_INVALID_PARAMS);for(i = 0; i < thiz->slot_nr; i++){if(thiz->slots[i] != NULL){dlist_foreach(thiz->slots[i], visit, ctx);}}return RET_OK;
}void hash_table_destroy(HashTable* thiz)
{size_t i = 0;if(thiz != NULL){for(i = 0; i < thiz->slot_nr; i++){if(thiz->slots[i] != NULL){dlist_destroy(thiz->slots[i]);thiz->slots[i] = NULL;}}free(thiz->slots);free(thiz);}return;
}#ifdef HASH_TABLE_TEST
#include "test_helper.c"int main(int argc, char* argv[])
{int i = 0;int n = 10000;int ret_data = 0;HashTable* hash_table = hash_table_create(NULL, NULL, hash_int, 31);for(i = 0; i < n; i++){assert(hash_table_length(hash_table) == i);assert(hash_table_insert(hash_table, (void*)i) == RET_OK);assert(hash_table_length(hash_table) == (i + 1));assert(hash_table_find(hash_table, cmp_int, (void*)i, (void**)&ret_data) == RET_OK);assert(ret_data == i);}for(i = 0; i < n; i++){assert(hash_table_delete(hash_table, cmp_int, (void*)i) == RET_OK);assert(hash_table_length(hash_table) == (n - i -1));assert(hash_table_find(hash_table, cmp_int, (void*)i, (void**)&ret_data) != RET_OK);}hash_table_destroy(hash_table);return 0;
}
#endif/*HASH_TABLE_TEST*/

5. 最后来复习一下以前写的几个文件

typedef.h

#include <stdio.h>
#include <assert.h>
#include <stdlib.h>#ifndef TYPEDEF_H
#define TYPEDEF_Htypedef enum _Ret
{RET_OK,RET_OOM,RET_STOP,RET_INVALID_PARAMS,RET_FAIL
}Ret;typedef void     (*DataDestroyFunc)(void* ctx, void* data);
typedef int      (*DataCompareFunc)(void* ctx, void* data);
typedef Ret      (*DataVisitFunc)(void* ctx, void* data);
typedef int       (*DataHashFunc)(void* data);#ifdef __cplusplus
#define DECLS_BEGIN extern "C" {
#define DECLS_END   }
#else
#define DECLS_BEGIN
#define DECLS_END
#endif/*__cplusplus*/#define return_if_fail(p) if(!(p)) \{printf("%s:%d Warning: "#p" failed.\n", \__func__, __LINE__); return;}
#define return_val_if_fail(p, ret) if(!(p)) \{printf("%s:%d Warning: "#p" failed.\n",\__func__, __LINE__); return (ret);}#define SAFE_FREE(p) if(p != NULL) {free(p); p = NULL;}typedef Ret (*SortFunc)(void** array, size_t nr, DataCompareFunc cmp);#endif/*TYPEDEF_H*/

dlist.h

#include <stdio.h>
#include "typedef.h"#ifndef DLIST_H
#define DLIST_HDECLS_BEGINstruct _DList;
typedef struct _DList DList;DList* dlist_create(DataDestroyFunc data_destroy, void* ctx);Ret dlist_insert(DList* thiz, size_t index, void* data);
Ret dlist_prepend(DList* thiz, void* data);
Ret dlist_append(DList* thiz, void* data);
Ret dlist_delete(DList* thiz, size_t index);
Ret dlist_get_by_index(DList* thiz, size_t index, void** data);
Ret dlist_set_by_index(DList* thiz, size_t index, void* data);
size_t   dlist_length(DList* thiz);
int      dlist_find(DList* thiz, DataCompareFunc cmp, void* ctx);
Ret      dlist_foreach(DList* thiz, DataVisitFunc visit, void* ctx);void dlist_destroy(DList* thiz);DECLS_END#endif/*DLIST*/