Nikhil Patel / Mbed 2 deprecated rpg_game

ECE 2035 final project

Dependencies:   mbed wave_player 4DGL-uLCD-SE MMA8452

hash_table.h@2:22d36e7740f1, 2019-04-15 (annotated)

Committer:
npatel387
Date:
Mon Apr 15 12:25:08 2019 +0000
Revision:
2:22d36e7740f1
Parent:
0:35660d7952f7 
final;

Who changed what in which revision?

UserRevisionLine numberNew contents of line
rconnorlawson 0:35660d7952f7 1 /****************************************************************************
rconnorlawson 0:35660d7952f7 2 * Include guards
rconnorlawson 0:35660d7952f7 3 *
rconnorlawson 0:35660d7952f7 4 * By using a preprecessor include guard like this one (along with the #endif
rconnorlawson 0:35660d7952f7 5 * at the bottom of the file), we can guarantee that the public interface for
rconnorlawson 0:35660d7952f7 6 * this module is only included once in each compilation unit. This prevents
rconnorlawson 0:35660d7952f7 7 * transitive dependencies from mistakenly including headers many times, and
rconnorlawson 0:35660d7952f7 8 * can also prevent infinite #include loops due to circular dependencies.
rconnorlawson 0:35660d7952f7 9 ***************************************************************************/
rconnorlawson 0:35660d7952f7 10 #ifndef HASHTABLE_H
rconnorlawson 0:35660d7952f7 11 #define HASHTABLE_H
rconnorlawson 0:35660d7952f7 12
rconnorlawson 0:35660d7952f7 13 /****************************************************************************
rconnorlawson 0:35660d7952f7 14 * Forward Declarations
rconnorlawson 0:35660d7952f7 15 *
rconnorlawson 0:35660d7952f7 16 * These declarations are for interface types that are private to the module,
rconnorlawson 0:35660d7952f7 17 * but are needed for external interfaces. Without a definition, the compiler
rconnorlawson 0:35660d7952f7 18 * (and therefore the user) does not have access to information about the
rconnorlawson 0:35660d7952f7 19 * member variables, and so the members cannot be used directly from modules
rconnorlawson 0:35660d7952f7 20 * that include this header. However, we do know that these structures are
rconnorlawson 0:35660d7952f7 21 * valid, and we can use pointers to them. This technique allows hiding the
rconnorlawson 0:35660d7952f7 22 * implementation details of the hash table module behind a clean public
rconnorlawson 0:35660d7952f7 23 * interface.
rconnorlawson 0:35660d7952f7 24 ***************************************************************************/
rconnorlawson 0:35660d7952f7 25 /**
rconnorlawson 0:35660d7952f7 26 * This defines a type that is a pointer to a function which takes
rconnorlawson 0:35660d7952f7 27 * an unsigned int argument and returns an unsigned int value.
rconnorlawson 0:35660d7952f7 28 * The name of the type is "HashFunction".
rconnorlawson 0:35660d7952f7 29 */
rconnorlawson 0:35660d7952f7 30 typedef unsigned int (*HashFunction)(unsigned int key);
rconnorlawson 0:35660d7952f7 31
rconnorlawson 0:35660d7952f7 32 /**
rconnorlawson 0:35660d7952f7 33 * This defines a type that is a _HashTable struct. The definition for
rconnorlawson 0:35660d7952f7 34 * _HashTable is implemented in hash_table.c.
rconnorlawson 0:35660d7952f7 35 *
rconnorlawson 0:35660d7952f7 36 * In other words, "HashTable" is an alternative name for "struct _HashTable".
rconnorlawson 0:35660d7952f7 37 * "HashTable" can be used to create a new struct variable.
rconnorlawson 0:35660d7952f7 38 */
rconnorlawson 0:35660d7952f7 39 typedef struct _HashTable HashTable;
rconnorlawson 0:35660d7952f7 40
rconnorlawson 0:35660d7952f7 41 /**
rconnorlawson 0:35660d7952f7 42 * This defines a type that is a _HashTableEntry struct. The definition for
rconnorlawson 0:35660d7952f7 43 * _HashTableEntry is implemented in hash_table.c.
rconnorlawson 0:35660d7952f7 44 *
rconnorlawson 0:35660d7952f7 45 * In other words, "HashTableEntry" is an alternative name for "struct _HashTableEntry".
rconnorlawson 0:35660d7952f7 46 * "HashTableEntry" can be used to create a new struct variable.
rconnorlawson 0:35660d7952f7 47 */
rconnorlawson 0:35660d7952f7 48 typedef struct _HashTableEntry HashTableEntry;
rconnorlawson 0:35660d7952f7 49
rconnorlawson 0:35660d7952f7 50 /**
rconnorlawson 0:35660d7952f7 51 * createHashTable
rconnorlawson 0:35660d7952f7 52 *
rconnorlawson 0:35660d7952f7 53 * Creates a hash table by allocating memory for it on the heap. Initialize num_buckets
rconnorlawson 0:35660d7952f7 54 * and hash based on function arguments. Allocate memory for buckets as an array of
rconnorlawson 0:35660d7952f7 55 * pointers to HashTableEntry objects based on the number of buckets available.
rconnorlawson 0:35660d7952f7 56 * Each bucket contains a singly linked list, whose nodes are HashTableEntry objects.
rconnorlawson 0:35660d7952f7 57 *
rconnorlawson 0:35660d7952f7 58 * @param myHashFunc The pointer to the custom hash function.
rconnorlawson 0:35660d7952f7 59 * @param numBuckets The number of buckets available in the hash table.
rconnorlawson 0:35660d7952f7 60 * @return a pointer to the new hash table
rconnorlawson 0:35660d7952f7 61 */
rconnorlawson 0:35660d7952f7 62 HashTable* createHashTable(HashFunction myHashFunc, unsigned int numBuckets);
rconnorlawson 0:35660d7952f7 63
rconnorlawson 0:35660d7952f7 64 /**
rconnorlawson 0:35660d7952f7 65 * destroyHashTable
rconnorlawson 0:35660d7952f7 66 *
rconnorlawson 0:35660d7952f7 67 * Destroy the hash table. The nodes (HashTableEntry objects) of singly linked
rconnorlawson 0:35660d7952f7 68 * list, the values stored on the linked list, the buckets, and the hashtable
rconnorlawson 0:35660d7952f7 69 * itself are freed from the heap. In other words, free all the allocated memory
rconnorlawson 0:35660d7952f7 70 * on heap that is associated with heap, including the values that users store in
rconnorlawson 0:35660d7952f7 71 * the hash table.
rconnorlawson 0:35660d7952f7 72 *
rconnorlawson 0:35660d7952f7 73 * @param myHashTable The pointer to the hash table.
rconnorlawson 0:35660d7952f7 74 *
rconnorlawson 0:35660d7952f7 75 */
rconnorlawson 0:35660d7952f7 76 void destroyHashTable(HashTable* myHashTable);
rconnorlawson 0:35660d7952f7 77
rconnorlawson 0:35660d7952f7 78 /**
rconnorlawson 0:35660d7952f7 79 * insertItem
rconnorlawson 0:35660d7952f7 80 *
rconnorlawson 0:35660d7952f7 81 * Insert the value into the hash table based on the key.
rconnorlawson 0:35660d7952f7 82 * In other words, create a new hash table entry and add it to a specific bucket.
rconnorlawson 0:35660d7952f7 83 *
rconnorlawson 0:35660d7952f7 84 * @param myHashTable The pointer to the hash table.
rconnorlawson 0:35660d7952f7 85 * @param key The key that corresponds to the value.
rconnorlawson 0:35660d7952f7 86 * @param value The value to be stored in the hash table.
rconnorlawson 0:35660d7952f7 87 * @return old value if it is overwritten, or NULL if not replaced
rconnorlawson 0:35660d7952f7 88 */
rconnorlawson 0:35660d7952f7 89 void* insertItem(HashTable* myHashTable, unsigned int key, void* value);
rconnorlawson 0:35660d7952f7 90
rconnorlawson 0:35660d7952f7 91 /**
rconnorlawson 0:35660d7952f7 92 * getItem
rconnorlawson 0:35660d7952f7 93 *
rconnorlawson 0:35660d7952f7 94 * Get the value that corresponds to the key in the hash table.
rconnorlawson 0:35660d7952f7 95 *
rconnorlawson 0:35660d7952f7 96 * @param myHashTable The pointer to the hash table.
rconnorlawson 0:35660d7952f7 97 * @param key The key that corresponds to the item.
rconnorlawson 0:35660d7952f7 98 * @return the value corresponding to the key, or NULL if the key is not present
rconnorlawson 0:35660d7952f7 99 */
rconnorlawson 0:35660d7952f7 100 void* getItem(HashTable* myHashTable, unsigned int key);
rconnorlawson 0:35660d7952f7 101
rconnorlawson 0:35660d7952f7 102 /**
rconnorlawson 0:35660d7952f7 103 * removeItem
rconnorlawson 0:35660d7952f7 104 *
rconnorlawson 0:35660d7952f7 105 * Remove the item in hash table based on the key and return the value stored in it.
rconnorlawson 0:35660d7952f7 106 * In other words, return the value and free the hash table entry from heap.
rconnorlawson 0:35660d7952f7 107 *
rconnorlawson 0:35660d7952f7 108 * @param myHashTable The pointer to the hash table.
rconnorlawson 0:35660d7952f7 109 * @param key The key that corresponds to the item.
rconnorlawson 0:35660d7952f7 110 * @return the pointer of the value corresponding to the key, or NULL if the key is not present
rconnorlawson 0:35660d7952f7 111 */
rconnorlawson 0:35660d7952f7 112 void* removeItem(HashTable* myHashTable, unsigned int key);
rconnorlawson 0:35660d7952f7 113
rconnorlawson 0:35660d7952f7 114 /**
rconnorlawson 0:35660d7952f7 115 * deleteItem
rconnorlawson 0:35660d7952f7 116 *
rconnorlawson 0:35660d7952f7 117 * Delete the item in the hash table based on the key. In other words, free the
rconnorlawson 0:35660d7952f7 118 * value stored in the hash table entry and the hash table entry itself from
rconnorlawson 0:35660d7952f7 119 * the heap.
rconnorlawson 0:35660d7952f7 120 *
rconnorlawson 0:35660d7952f7 121 * @param myHashTable The pointer to the hash table.
rconnorlawson 0:35660d7952f7 122 * @param key The key that corresponds to the item.
rconnorlawson 0:35660d7952f7 123 *
rconnorlawson 0:35660d7952f7 124 */
rconnorlawson 0:35660d7952f7 125 void deleteItem(HashTable* myHashTable, unsigned int key);
rconnorlawson 0:35660d7952f7 126
npatel387 2:22d36e7740f1 127 #endif