/****************************************************************************** * Declarations, global to other of the GIF-HASH.C module. * * * * Written by Gershon Elber, Jun 1989 * ******************************************************************************* * History: * * 14 Jun 89 - Version 1.0 by Gershon Elber. * ******************************************************************************/ #define HT_SIZE 8192 /* 12bits = 4096 or twice as big! */ #define HT_KEY_MASK 0x1FFF /* 13bits keys */ #define HT_KEY_NUM_BITS 13 /* 13bits keys */ #define HT_MAX_KEY 8191 /* 13bits - 1, maximal code possible */ #define HT_MAX_CODE 4095 /* Biggest code possible in 12 bits. */ /* The 32 bits of the long are divided into two parts for the key & code: */ /* 1. The code is 12 bits as our compression algorithm is limited to 12bits */ /* 2. The key is 12 bits Prefix code + 8 bit new char or 20 bits. */ #define HT_GET_KEY(l) (l >> 12) #define HT_GET_CODE(l) (l & 0x0FFF) #define HT_PUT_KEY(l) (l << 12) #define HT_PUT_CODE(l) (l & 0x0FFF) typedef struct GifHashTableType { unsigned long HTable[HT_SIZE]; } GifHashTableType; GifHashTableType *_InitHashTable(void); void _ClearHashTable(GifHashTableType *HashTable); void _InsertHashTable(GifHashTableType *HashTable, unsigned long Key, int Code); int _ExistsHashTable(GifHashTableType *HashTable, unsigned long Key); G