uthash: a hash table for C structures

Any C structure can be stored in a hash table using uthash. Just add a UT_hash_handle to the structure and choose one or more fields in your structure to act as the key. Then use these macros to store, retrieve or delete items from the hash table.
Example 1. Adding an item to a hash.

    #include "uthash.h"

    struct my_struct {
        int id;            /* we'll use this field as the key */
        char name[10];
        UT_hash_handle hh; /* makes this structure hashable */
    };

    struct my_struct *users = NULL;

    void add_user(struct my_struct *s) {
        HASH_ADD_INT(users, id, s);
    }

Example 2. Looking up an item in a hash.

    struct my_struct *find_user(int user_id) {
        struct my_struct *s;

        HASH_FIND_INT(users, &user_id, s);
        return s;
    }

Example 3. Deleting an item from a hash.

    void delete_user(struct my_struct *user) {
        HASH_DEL(users, user);
    }

For more information and examples, please see the User Guide.