sqlite/ext/fts1/fts1_hash.h
drh 5db455e7b5 Refactor the FTS1 module so that its name is "fts1" instead of "fulltext",
so that all symbols with external linkage begin with "sqlite3Fts1", and
so that all filenames begin with "fts1". (CVS 3377)

FossilOrigin-Name: e1891f0dc58e5498a8845d8b9b5b092d7f9c7003
2006-08-31 15:07:14 +00:00

113 lines
4.0 KiB
C

/*
** 2001 September 22
**
** The author disclaims copyright to this source code. In place of
** a legal notice, here is a blessing:
**
** May you do good and not evil.
** May you find forgiveness for yourself and forgive others.
** May you share freely, never taking more than you give.
**
*************************************************************************
** This is the header file for the generic hash-table implemenation
** used in SQLite. We've modified it slightly to serve as a standalone
** hash table implementation for the full-text indexing module.
**
*/
#ifndef _FTS1_HASH_H_
#define _FTS1_HASH_H_
/* Forward declarations of structures. */
typedef struct fts1Hash fts1Hash;
typedef struct fts1HashElem fts1HashElem;
/* A complete hash table is an instance of the following structure.
** The internals of this structure are intended to be opaque -- client
** code should not attempt to access or modify the fields of this structure
** directly. Change this structure only by using the routines below.
** However, many of the "procedures" and "functions" for modifying and
** accessing this structure are really macros, so we can't really make
** this structure opaque.
*/
struct fts1Hash {
char keyClass; /* HASH_INT, _POINTER, _STRING, _BINARY */
char copyKey; /* True if copy of key made on insert */
int count; /* Number of entries in this table */
fts1HashElem *first; /* The first element of the array */
void *(*xMalloc)(int); /* malloc() function to use */
void (*xFree)(void *); /* free() function to use */
int htsize; /* Number of buckets in the hash table */
struct _fts1ht { /* the hash table */
int count; /* Number of entries with this hash */
fts1HashElem *chain; /* Pointer to first entry with this hash */
} *ht;
};
/* Each element in the hash table is an instance of the following
** structure. All elements are stored on a single doubly-linked list.
**
** Again, this structure is intended to be opaque, but it can't really
** be opaque because it is used by macros.
*/
struct fts1HashElem {
fts1HashElem *next, *prev; /* Next and previous elements in the table */
void *data; /* Data associated with this element */
void *pKey; int nKey; /* Key associated with this element */
};
/*
** There are 2 different modes of operation for a hash table:
**
** FTS1_HASH_STRING pKey points to a string that is nKey bytes long
** (including the null-terminator, if any). Case
** is respected in comparisons.
**
** FTS1_HASH_BINARY pKey points to binary data nKey bytes long.
** memcmp() is used to compare keys.
**
** A copy of the key is made if the copyKey parameter to fts1HashInit is 1.
*/
#define FTS1_HASH_STRING 1
#define FTS1_HASH_BINARY 2
/*
** Access routines. To delete, insert a NULL pointer.
*/
void sqlite3Fts1HashInit(fts1Hash*, int keytype, int copyKey);
void *sqlite3Fts1HashInsert(fts1Hash*, const void *pKey, int nKey, void *pData);
void *sqlite3Fts1HashFind(const fts1Hash*, const void *pKey, int nKey);
void sqlite3Fts1HashClear(fts1Hash*);
/*
** Shorthand for the functions above
*/
#define fts1HashInit sqlite3Fts1HashInit
#define fts1HashInsert sqlite3Fts1HashInsert
#define fts1HashFind sqlite3Fts1HashFind
#define fts1HashClear sqlite3Fts1HashClear
/*
** Macros for looping over all elements of a hash table. The idiom is
** like this:
**
** fts1Hash h;
** fts1HashElem *p;
** ...
** for(p=fts1HashFirst(&h); p; p=fts1HashNext(p)){
** SomeStructure *pData = fts1HashData(p);
** // do something with pData
** }
*/
#define fts1HashFirst(H) ((H)->first)
#define fts1HashNext(E) ((E)->next)
#define fts1HashData(E) ((E)->data)
#define fts1HashKey(E) ((E)->pKey)
#define fts1HashKeysize(E) ((E)->nKey)
/*
** Number of entries in a hash table
*/
#define fts1HashCount(H) ((H)->count)
#endif /* _FTS1_HASH_H_ */