hashtable.h

#pragma once

/**
 * @file hashtable.h
 * @brief Local hash-table implementation.
 *
 * @author Valérian Rousset
 */

#include <stddef.h> // for size_t
#include <stdint.h> // for int32_t (weeks 04 to 06)

#include "error.h" // for error_code


 
/*
 * Definition of type for local hash-tables keys
 */
 typedef const char* pps_key_t;

/*
 * Definition of type for local hash-tables values
 */
 typedef const char* pps_value_t;

/*
 * key-value pair
 */
 typedef struct 
 {
     pps_key_t key;
     pps_value_t value;
 } kv_pair_t;

/*
 * Definition of type for local hash-tables buckets
 */
 typedef struct bucket_t bucket_t;


/*
 * Definition of local hash-table type
 */
#define HTABLE_SIZE 256

struct Htable_t{
    bucket_t* elements;
    size_t size;
};

typedef struct Htable_t* Htable_t;

// Only from week 07
#define NO_HTABLE ((Htable_t) NULL)

typedef struct
{
    kv_pair_t* elems;
    size_t size;
    size_t allocated;
} kv_list_t;

/**
 * @brief create a kv list
 * @return the kv list
 */
kv_list_t* create_kv_list();

/**
 * @brief get all the pairs from the table
 * @param list the list to complete
 * @return an error code of an error occured
 */
error_code get_kv_pair(kv_list_t* list, Htable_t table);


/**
 * @brief construct a hash-table of the given size.
 *    Note: does NOTHING until week 07.
 * @param size number of buckets in the new hash-table
 * @return the newly allocated hash-table
 */
Htable_t construct_Htable(size_t size);

/**
 * @brief delete the given hash-table
 *    Note: does NOTHING until week 07.
 * @param table the hash-table to free (passed by reference)
 */
void delete_Htable_and_content(Htable_t* table);

/**
 * @brief add a key:value pair to hash-table
 * @param table the table where to add
 * @param key the key to which the value shall be associated
 * @param value the value to be added
 * @return 0 on success; error code on errror (see error.h)
 */
error_code add_Htable_value(Htable_t table, pps_key_t key, pps_value_t value);

/**
 * @brief get a value for a given in the given hash-table
 * @param table the table where to get
 * @param key the key associated to the wanted value
 * @return the associated value
 */
pps_value_t get_Htable_value(Htable_t table, pps_key_t key);

/**
 * @brief compute the hash for the given key and size of hash-table.
 *      Note: although this is a local function, it is exposed here
 *            for test/grading purposes.
 * @param key the key onto compute the hash
 * @param table_size size of the containing table
 * @return a hash value in range [0..table_size-1], or SIZE_MAX if error
 */
size_t hash_function(pps_key_t key, size_t table_size);

/**
 * @brief get the content of the table
 *    Note: does NOTHING until week 08.
 * @param table table to read from
 * @return the list of key values from the given table, NULL if a failure occured
 */
kv_list_t *get_Htable_content(Htable_t table);

/**
 * @brief delete a key:value pair from the hash-table
 *    Note: does NOTHING until week 10.
 * @param table the table where to delete
 * @param key the key which is to be delete
 * @return 0 on success; error code on errror (see error.h)
 */
error_code del_Htable_key(Htable_t table, pps_key_t key);

/**
 * @brief free a key-value pair content (both of them)
 *    Note: does NOTHING until week 07.
 * @param kv the key-value pair to free
 */
void kv_pair_free(kv_pair_t *kv);

/**
 * @brief free a kv_list and it's content
 *    Note: does NOTHING until week 08.
 * @param list the list to free
 */
void kv_list_free(kv_list_t *list);