text: #ifndef __TRGM_H__
  #define __TRGM_H__
  
  #include "postgres.h"
  
  #include "access/gist.h"
  #include "access/itup.h"
  #include "utils/builtins.h"
  #include "storage/bufpage.h"
  
  /* options */
  #define LPADDING		2
  #define RPADDING		1
  #define KEEPONLYALNUM
  #define IGNORECASE
  #define DIVUNION
  
  
  typedef char trgm[3];
  
  #define CMPCHAR(a,b) ( ((a)==(b)) ? 0 : ( ((a)<(b)) ? -1 : 1 ) )
  #define CMPPCHAR(a,b,i)  CMPCHAR( *(((char*)(a))+i), *(((char*)(b))+i) )
  #define CMPTRGM(a,b) ( CMPPCHAR(a,b,0) ? CMPPCHAR(a,b,0) : ( CMPPCHAR(a,b,1) ? CMPPCHAR(a,b,1) : CMPPCHAR(a,b,2) ) )
  
  #define CPTRGM(a,b) do {				\
  	*(((char*)(a))+0) = *(((char*)(b))+0);	\
  	*(((char*)(a))+1) = *(((char*)(b))+1);	\
  	*(((char*)(a))+2) = *(((char*)(b))+2);	\
  } while(0);
  
  
  typedef struct
  {
  	int4		len;
  	uint8		flag;
  	char		data[1];
  }	TRGM;
  
  #define TRGMHRDSIZE		  (sizeof(int4)+sizeof(uint8))
  
  /* gist */
  #define BITBYTE 8
  #define SIGLENINT  3			/* >122 => key will toast, so very slow!!! */
  #define SIGLEN	( sizeof(int)*SIGLENINT )
  
  #define SIGLENBIT (SIGLEN*BITBYTE - 1)	/* see makesign */
  
  typedef char BITVEC[SIGLEN];
  typedef char *BITVECP;
  
  #define LOOPBYTE(a) \
  				for(i=0;i<SIGLEN;i++) {\
  								a;\
  				}
  
  #define GETBYTE(x,i) ( *( (BITVECP)(x) + (int)( (i) / BITBYTE ) ) )
  #define GETBITBYTE(x,i) ( ((char)(x)) >> i & 0x01 )
  #define CLRBIT(x,i)   GETBYTE(x,i) &= ~( 0x01 << ( (i) % BITBYTE ) )
  #define SETBIT(x,i)   GETBYTE(x,i) |=  ( 0x01 << ( (i) % BITBYTE ) )
  #define GETBIT(x,i) ( (GETBYTE(x,i) >> ( (i) % BITBYTE )) & 0x01 )
  
  #define HASHVAL(val) (((unsigned int)(val)) % SIGLENBIT)
  #define HASH(sign, val) SETBIT((sign), HASHVAL(val))
  
  #define ARRKEY			0x01
  #define SIGNKEY			0x02
  #define ALLISTRUE		0x04
  
  #define ISARRKEY(x) ( ((TRGM*)x)->flag & ARRKEY )
  #define ISSIGNKEY(x)	( ((TRGM*)x)->flag & SIGNKEY )
  #define ISALLTRUE(x)	( ((TRGM*)x)->flag & ALLISTRUE )
  
  #define CALCGTSIZE(flag, len) ( TRGMHRDSIZE + ( ( (flag) & ARRKEY ) ? ((len)*sizeof(trgm)) : (((flag) & ALLISTRUE) ? 0 : SIGLEN) ) )
  #define GETSIGN(x)		( (BITVECP)( (char*)x+TRGMHRDSIZE ) )
  #define GETARR(x)		( (trgm*)( (char*)x+TRGMHRDSIZE ) )
  #define ARRNELEM(x) ( ( ((TRGM*)x)->len - TRGMHRDSIZE )/sizeof(trgm) )
  
  extern float4 trgm_limit;
  TRGM	   *generate_trgm(char *str, int slen);
  float4		cnt_sml(TRGM * trg1, TRGM * trg2);
  
  #endif
  