39 lines
1.7 KiB
C++
39 lines
1.7 KiB
C++
#pragma once
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/* Perfect hashing function library. Contains functions to generate perfect
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hashing functions
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* (C) Mike van Emmerik
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*/
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#include <stdint.h>
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/* Prototypes */
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void hashCleanup(void); /* Frees memory allocated by hashParams() */
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void map(void); /* Part 1 of creating the tables */
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/* The application must provide these functions: */
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void getKey(int i, uint8_t **pKeys);/* Set *keys to point to the i+1th key */
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void dispKey(int i); /* Display the key */
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class PatternHasher
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{
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uint16_t *T1base, *T2base; /* Pointers to start of T1, T2 */
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int NumEntry; /* Number of entries in the hash table (# keys) */
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int EntryLen; /* Size (bytes) of each entry (size of keys) */
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int SetSize; /* Size of the char set */
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char SetMin; /* First char in the set */
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int NumVert; /* c times NumEntry */
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int *graphNode; /* The array of edges */
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int *graphNext; /* Linked list of edges */
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int *graphFirst;/* First edge at a vertex */
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public:
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uint16_t *readT1(void); /* Returns a pointer to the T1 table */
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uint16_t *readT2(void); /* Returns a pointer to the T2 table */
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uint16_t *readG(void); /* Returns a pointer to the g table */
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void init(int _NumEntry, int _EntryLen, int _SetSize, char _SetMin,int _NumVert); /* Set the parameters for the hash table */
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void cleanup();
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int hash(unsigned char *string); //!< Hash the string to an int 0 .. NUMENTRY-1
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};
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extern PatternHasher g_pattern_hasher;
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/* Macro reads a LH uint16_t from the image regardless of host convention */
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#ifndef LH
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#define LH(p) ((int)((uint8_t *)(p))[0] + ((int)((uint8_t *)(p))[1] << 8))
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#endif
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