251cced1f8
Various minor things done to project files Updated sample extension project file and updated makefile to the new unified version (more changes likely on the way) Updated regex project file and makefile --HG-- extra : convert_revision : svn%3A39bc706e-5318-0410-9160-8a85361fbb7c/trunk%401971
111 lines
3.8 KiB
C
111 lines
3.8 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.
|
|
**
|
|
** $Id$
|
|
*/
|
|
#ifndef _SQLITE_HASH_H_
|
|
#define _SQLITE_HASH_H_
|
|
|
|
/* Forward declarations of structures. */
|
|
typedef struct Hash Hash;
|
|
typedef struct HashElem HashElem;
|
|
|
|
/* 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 Hash {
|
|
char keyClass; /* SQLITE_HASH_INT, _POINTER, _STRING, _BINARY */
|
|
char copyKey; /* True if copy of key made on insert */
|
|
int count; /* Number of entries in this table */
|
|
int htsize; /* Number of buckets in the hash table */
|
|
HashElem *first; /* The first element of the array */
|
|
struct _ht { /* the hash table */
|
|
int count; /* Number of entries with this hash */
|
|
HashElem *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 HashElem {
|
|
HashElem *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 4 different modes of operation for a hash table:
|
|
**
|
|
** SQLITE_HASH_INT nKey is used as the key and pKey is ignored.
|
|
**
|
|
** SQLITE_HASH_POINTER pKey is used as the key and nKey is ignored.
|
|
**
|
|
** SQLITE_HASH_STRING pKey points to a string that is nKey bytes long
|
|
** (including the null-terminator, if any). Case
|
|
** is ignored in comparisons.
|
|
**
|
|
** SQLITE_HASH_BINARY pKey points to binary data nKey bytes long.
|
|
** memcmp() is used to compare keys.
|
|
**
|
|
** A copy of the key is made for SQLITE_HASH_STRING and SQLITE_HASH_BINARY
|
|
** if the copyKey parameter to HashInit is 1.
|
|
*/
|
|
/* #define SQLITE_HASH_INT 1 // NOT USED */
|
|
/* #define SQLITE_HASH_POINTER 2 // NOT USED */
|
|
#define SQLITE_HASH_STRING 3
|
|
#define SQLITE_HASH_BINARY 4
|
|
|
|
/*
|
|
** Access routines. To delete, insert a NULL pointer.
|
|
*/
|
|
void sqlite3HashInit(Hash*, int keytype, int copyKey);
|
|
void *sqlite3HashInsert(Hash*, const void *pKey, int nKey, void *pData);
|
|
void *sqlite3HashFind(const Hash*, const void *pKey, int nKey);
|
|
HashElem *sqlite3HashFindElem(const Hash*, const void *pKey, int nKey);
|
|
void sqlite3HashClear(Hash*);
|
|
|
|
/*
|
|
** Macros for looping over all elements of a hash table. The idiom is
|
|
** like this:
|
|
**
|
|
** Hash h;
|
|
** HashElem *p;
|
|
** ...
|
|
** for(p=sqliteHashFirst(&h); p; p=sqliteHashNext(p)){
|
|
** SomeStructure *pData = sqliteHashData(p);
|
|
** // do something with pData
|
|
** }
|
|
*/
|
|
#define sqliteHashFirst(H) ((H)->first)
|
|
#define sqliteHashNext(E) ((E)->next)
|
|
#define sqliteHashData(E) ((E)->data)
|
|
#define sqliteHashKey(E) ((E)->pKey)
|
|
#define sqliteHashKeysize(E) ((E)->nKey)
|
|
|
|
/*
|
|
** Number of entries in a hash table
|
|
*/
|
|
#define sqliteHashCount(H) ((H)->count)
|
|
|
|
#endif /* _SQLITE_HASH_H_ */
|