db.h

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	 */
	struct __cq_fq {
		struct __dbc *tqh_first;
		struct __dbc **tqh_last;
	} free_queue;
	struct __cq_aq {
		struct __dbc *tqh_first;
		struct __dbc **tqh_last;
	} active_queue;
	struct __cq_jq {
		struct __dbc *tqh_first;
		struct __dbc **tqh_last;
	} join_queue;

	/*
	 * Secondary index support.
	 *
	 * Linked list of secondary indices -- set in the primary.
	 *
	 * !!!
	 * Explicit representations of structures from queue.h.
	 * LIST_HEAD(s_secondaries, __db);
	 */
	struct {
		struct __db *lh_first;
	} s_secondaries;

	/*
	 * List entries for secondaries, and reference count of how
	 * many threads are updating this secondary (see __db_c_put).
	 *
	 * !!!
	 * Note that these are synchronized by the primary's mutex, but
	 * filled in in the secondaries.
	 *
	 * !!!
	 * Explicit representations of structures from queue.h.
	 * LIST_ENTRY(__db) s_links;
	 */
	struct {
		struct __db *le_next;
		struct __db **le_prev;
	} s_links;
	u_int32_t s_refcnt;

	/* Secondary callback and free functions -- set in the secondary. */
	int	(*s_callback) __P((DB *, const DBT *, const DBT *, DBT *));

	/* Reference to primary -- set in the secondary. */
	DB	*s_primary;

	/* API-private structure: used by DB 1.85, C++, Java, Perl and Tcl */
	void	*api_internal;

	/* Subsystem-private structure. */
	void	*bt_internal;		/* Btree/Recno access method. */
	void	*h_internal;		/* Hash access method. */
	void	*q_internal;		/* Queue access method. */
	void	*xa_internal;		/* XA. */

					/* Methods. */
	int  (*associate) __P((DB *, DB_TXN *, DB *, int (*)(DB *, const DBT *,
		const DBT *, DBT *), u_int32_t));
	int  (*close) __P((DB *, u_int32_t));
	int  (*cursor) __P((DB *, DB_TXN *, DBC **, u_int32_t));
	int  (*del) __P((DB *, DB_TXN *, DBT *, u_int32_t));
	int  (*dump) __P((DB *,
		const char *, int (*)(void *, const void *), void *, int, int));
	void (*err) __P((DB *, int, const char *, ...));
	void (*errx) __P((DB *, const char *, ...));
	int  (*fd) __P((DB *, int *));
	int  (*get) __P((DB *, DB_TXN *, DBT *, DBT *, u_int32_t));
	int  (*pget) __P((DB *, DB_TXN *, DBT *, DBT *, DBT *, u_int32_t));
	int  (*get_byteswapped) __P((DB *, int *));
	int  (*get_cachesize) __P((DB *, u_int32_t *, u_int32_t *, int *));
	int  (*get_dbname) __P((DB *, const char **, const char **));
	int  (*get_encrypt_flags) __P((DB *, u_int32_t *));
	DB_ENV *(*get_env) __P((DB *));
	void (*get_errfile) __P((DB *, FILE **));
	void (*get_errpfx) __P((DB *, const char **));
	int  (*get_flags) __P((DB *, u_int32_t *));
	int  (*get_lorder) __P((DB *, int *));
	int  (*get_open_flags) __P((DB *, u_int32_t *));
	int  (*get_pagesize) __P((DB *, u_int32_t *));
	int  (*get_transactional) __P((DB *));
	int  (*get_type) __P((DB *, DBTYPE *));
	int  (*join) __P((DB *, DBC **, DBC **, u_int32_t));
	int  (*key_range) __P((DB *,
		DB_TXN *, DBT *, DB_KEY_RANGE *, u_int32_t));
	int  (*open) __P((DB *, DB_TXN *,
		const char *, const char *, DBTYPE, u_int32_t, int));
	int  (*put) __P((DB *, DB_TXN *, DBT *, DBT *, u_int32_t));
	int  (*remove) __P((DB *, const char *, const char *, u_int32_t));
	int  (*rename) __P((DB *,
	    const char *, const char *, const char *, u_int32_t));
	int  (*truncate) __P((DB *, DB_TXN *, u_int32_t *, u_int32_t));
	int  (*set_append_recno) __P((DB *, int (*)(DB *, DBT *, db_recno_t)));
	int  (*set_alloc) __P((DB *, void *(*)(size_t),
		void *(*)(void *, size_t), void (*)(void *)));
	int  (*set_cachesize) __P((DB *, u_int32_t, u_int32_t, int));
	int  (*set_dup_compare) __P((DB *,
	    int (*)(DB *, const DBT *, const DBT *)));
	int  (*set_encrypt) __P((DB *, const char *, u_int32_t));
	void (*set_errcall) __P((DB *,
	    void (*)(const DB_ENV *, const char *, const char *)));
	void (*set_errfile) __P((DB *, FILE *));
	void (*set_errpfx) __P((DB *, const char *));
	int  (*set_feedback) __P((DB *, void (*)(DB *, int, int)));
	int  (*set_flags) __P((DB *, u_int32_t));
	int  (*set_lorder) __P((DB *, int));
	void (*set_msgcall) __P((DB *, void (*)(const DB_ENV *, const char *)));
	void (*get_msgfile) __P((DB *, FILE **));
	void (*set_msgfile) __P((DB *, FILE *));
	int  (*set_pagesize) __P((DB *, u_int32_t));
	int  (*set_paniccall) __P((DB *, void (*)(DB_ENV *, int)));
	int  (*stat) __P((DB *, DB_TXN *, void *, u_int32_t));
	int  (*stat_print) __P((DB *, u_int32_t));
	int  (*sync) __P((DB *, u_int32_t));
	int  (*upgrade) __P((DB *, const char *, u_int32_t));
	int  (*verify) __P((DB *,
	    const char *, const char *, FILE *, u_int32_t));

	int  (*get_bt_minkey) __P((DB *, u_int32_t *));
	int  (*set_bt_compare) __P((DB *,
	    int (*)(DB *, const DBT *, const DBT *)));
	int  (*set_bt_maxkey) __P((DB *, u_int32_t));
	int  (*set_bt_minkey) __P((DB *, u_int32_t));
	int  (*set_bt_prefix) __P((DB *,
	    size_t (*)(DB *, const DBT *, const DBT *)));

	int  (*get_h_ffactor) __P((DB *, u_int32_t *));
	int  (*get_h_nelem) __P((DB *, u_int32_t *));
	int  (*set_h_ffactor) __P((DB *, u_int32_t));
	int  (*set_h_hash) __P((DB *,
	    u_int32_t (*)(DB *, const void *, u_int32_t)));
	int  (*set_h_nelem) __P((DB *, u_int32_t));

	int  (*get_re_delim) __P((DB *, int *));
	int  (*get_re_len) __P((DB *, u_int32_t *));
	int  (*get_re_pad) __P((DB *, int *));
	int  (*get_re_source) __P((DB *, const char **));
	int  (*set_re_delim) __P((DB *, int));
	int  (*set_re_len) __P((DB *, u_int32_t));
	int  (*set_re_pad) __P((DB *, int));
	int  (*set_re_source) __P((DB *, const char *));

	int  (*get_q_extentsize) __P((DB *, u_int32_t *));
	int  (*set_q_extentsize) __P((DB *, u_int32_t));

	int  (*db_am_remove) __P((DB *, DB_TXN *, const char *, const char *));
	int  (*db_am_rename) __P((DB *, DB_TXN *,
	    const char *, const char *, const char *));

	/*
	 * Never called; these are a place to save function pointers
	 * so that we can undo an associate.
	 */
	int  (*stored_get) __P((DB *, DB_TXN *, DBT *, DBT *, u_int32_t));
	int  (*stored_close) __P((DB *, u_int32_t));

#define	DB_OK_BTREE	0x01
#define	DB_OK_HASH	0x02
#define	DB_OK_QUEUE	0x04
#define	DB_OK_RECNO	0x08
	u_int32_t	am_ok;		/* Legal AM choices. */

#define	DB_AM_CHKSUM		0x00000001 /* Checksumming. */
#define	DB_AM_CL_WRITER		0x00000002 /* Allow writes in client replica. */
#define	DB_AM_COMPENSATE	0x00000004 /* Created by compensating txn. */
#define	DB_AM_CREATED		0x00000008 /* Database was created upon open. */
#define	DB_AM_CREATED_MSTR	0x00000010 /* Encompassing file was created. */
#define	DB_AM_DBM_ERROR		0x00000020 /* Error in DBM/NDBM database. */
#define	DB_AM_DELIMITER		0x00000040 /* Variable length delimiter set. */
#define	DB_AM_DIRTY		0x00000080 /* Support Dirty Reads. */
#define	DB_AM_DISCARD		0x00000100 /* Discard any cached pages. */
#define	DB_AM_DUP		0x00000200 /* DB_DUP. */
#define	DB_AM_DUPSORT		0x00000400 /* DB_DUPSORT. */
#define	DB_AM_ENCRYPT		0x00000800 /* Encryption. */
#define	DB_AM_FIXEDLEN		0x00001000 /* Fixed-length records. */
#define	DB_AM_INMEM		0x00002000 /* In-memory; no sync on close. */
#define	DB_AM_INORDER		0x00004000 /* DB_INORDER. */
#define	DB_AM_IN_RENAME		0x00008000 /* File is being renamed. */
#define	DB_AM_NOT_DURABLE	0x00010000 /* Do not log changes. */
#define	DB_AM_OPEN_CALLED	0x00020000 /* DB->open called. */
#define	DB_AM_PAD		0x00040000 /* Fixed-length record pad. */
#define	DB_AM_PGDEF		0x00080000 /* Page size was defaulted. */
#define	DB_AM_RDONLY		0x00100000 /* Database is readonly. */
#define	DB_AM_RECNUM		0x00200000 /* DB_RECNUM. */
#define	DB_AM_RECOVER		0x00400000 /* DB opened by recovery routine. */
#define	DB_AM_RENUMBER		0x00800000 /* DB_RENUMBER. */
#define	DB_AM_REPLICATION	0x01000000 /* An internal replication file. */
#define	DB_AM_REVSPLITOFF	0x02000000 /* DB_REVSPLITOFF. */
#define	DB_AM_SECONDARY		0x04000000 /* Database is a secondary index. */
#define	DB_AM_SNAPSHOT		0x08000000 /* DB_SNAPSHOT. */
#define	DB_AM_SUBDB		0x10000000 /* Subdatabases supported. */
#define	DB_AM_SWAP		0x20000000 /* Pages need to be byte-swapped. */
#define	DB_AM_TXN		0x40000000 /* Opened in a transaction. */
#define	DB_AM_VERIFYING		0x80000000 /* DB handle is in the verifier. */
	u_int32_t orig_flags;		   /* Flags at  open, for refresh. */
	u_int32_t flags;
};

/*
 * Macros for bulk get.  These are only intended for the C API.
 * For C++, use DbMultiple*Iterator.
 */
#define	DB_MULTIPLE_INIT(pointer, dbt)					\
	(pointer = (u_int8_t *)(dbt)->data +				\
	    (dbt)->ulen - sizeof(u_int32_t))
#define	DB_MULTIPLE_NEXT(pointer, dbt, retdata, retdlen)		\
	do {								\
		if (*((u_int32_t *)(pointer)) == (u_int32_t)-1) {	\
			retdata = NULL;					\
			pointer = NULL;					\
			break;						\
		}							\
		retdata = (u_int8_t *)					\
		    (dbt)->data + *(u_int32_t *)(pointer);		\
		(pointer) = (u_int32_t *)(pointer) - 1;			\
		retdlen = *(u_int32_t *)(pointer);			\
		(pointer) = (u_int32_t *)(pointer) - 1;			\
		if (retdlen == 0 &&					\
		    retdata == (u_int8_t *)(dbt)->data)			\
			retdata = NULL;					\
	} while (0)
#define	DB_MULTIPLE_KEY_NEXT(pointer, dbt, retkey, retklen, retdata, retdlen) \
	do {								\
		if (*((u_int32_t *)(pointer)) == (u_int32_t)-1) {	\
			retdata = NULL;					\
			retkey = NULL;					\
			pointer = NULL;					\
			break;						\
		}							\
		retkey = (u_int8_t *)					\
		    (dbt)->data + *(u_int32_t *)(pointer);		\
		(pointer) = (u_int32_t *)(pointer) - 1;			\
		retklen = *(u_int32_t *)(pointer);			\
		(pointer) = (u_int32_t *)(pointer) - 1;			\
		retdata = (u_int8_t *)					\
		    (dbt)->data + *(u_int32_t *)(pointer);		\
		(pointer) = (u_int32_t *)(pointer) - 1;			\
		retdlen = *(u_int32_t *)(pointer);			\
		(pointer) = (u_int32_t *)(pointer) - 1;			\
	} while (0)

#define	DB_MULTIPLE_RECNO_NEXT(pointer, dbt, recno, retdata, retdlen)   \
	do {								\
		if (*((u_int32_t *)(pointer)) == (u_int32_t)0) {	\
			recno = 0;					\
			retdata = NULL;					\
			pointer = NULL;					\
			break;						\
		}							\
		recno = *(u_int32_t *)(pointer);			\
		(pointer) = (u_int32_t *)(pointer) - 1;			\
		retdata = (u_int8_t *)					\
		    (dbt)->data + *(u_int32_t *)(pointer);		\
		(pointer) = (u_int32_t *)(pointer) - 1;			\
		retdlen = *(u_int32_t *)(pointer);			\
		(pointer) = (u_int32_t *)(pointer) - 1;			\
	} while (0)

/*******************************************************
 * Access method cursors.
 *******************************************************/
struct __dbc {
	DB *dbp;			/* Related DB access method. */
	DB_TXN	 *txn;			/* Associated transaction. */

	/*
	 * Active/free cursor queues.
	 *
	 * !!!
	 * Explicit representations of structures from queue.h.
	 * TAILQ_ENTRY(__dbc) links;
	 */
	struct {
		DBC *tqe_next;
		DBC **tqe_prev;
	} links;

	/*
	 * The DBT *'s below are used by the cursor routines to return
	 * data to the user when DBT flags indicate that DB should manage
	 * the returned memory.  They point at a DBT containing the buffer
	 * and length that will be used, and "belonging" to the handle that
	 * should "own" this memory.  This may be a "my_*" field of this
	 * cursor--the default--or it may be the corresponding field of
	 * another cursor, a DB handle, a join cursor, etc.  In general, it
	 * will be whatever handle the user originally used for the current
	 * DB interface call.
	 */
	DBT	 *rskey;		/* Returned secondary key. */
	DBT	 *rkey;			/* Returned [primary] key. */
	DBT	 *rdata;		/* Returned data. */

	DBT	  my_rskey;		/* Space for returned secondary key. */
	DBT	  my_rkey;		/* Space for returned [primary] key. */
	DBT	  my_rdata;		/* Space for returned data. */

	u_int32_t lid;			/* Default process' locker id. */
	u_int32_t locker;		/* Locker for this operation. */
	DBT	  lock_dbt;		/* DBT referencing lock. */
	DB_LOCK_ILOCK lock;		/* Object to be locked. */
	DB_LOCK	  mylock;		/* CDB lock held on this cursor. */

	u_int	  cl_id;		/* Remote client id. */

	DBTYPE	  dbtype;		/* Cursor type. */

	DBC_INTERNAL *internal;		/* Access method private. */

	int (*c_close) __P((DBC *));	/* Methods: public. */
	int (*c_count) __P((DBC *, db_recno_t *, u_int32_t));
	int (*c_del) __P((DBC *, u_int32_t));
	int (*c_dup) __P((DBC *, DBC **, u_int32_t));
	int (*c_get) __P((DBC *, DBT *, DBT *, u_int32_t));
	int (*c_pget) __P((DBC *, DBT *, DBT *, DBT *, u_int32_t));
	int (*c_put) __P((DBC *, DBT *, DBT *, u_int32_t));

					/* Methods: private. */
	int (*c_am_bulk) __P((DBC *, DBT *, u_int32_t));
	int (*c_am_close) __P((DBC *, db_pgno_t, int *));
	int (*c_am_del) __P((DBC *));
	int (*c_am_destroy) __P((DBC *));
	int (*c_am_get) __P((DBC *, DBT *, DBT *, u_int32_t, db_pgno_t *));
	int (*c_am_put) __P((DBC *, DBT *, DBT *, u_int32_t, db_pgno_t *));
	int (*c_am_writelock) __P((DBC *));

#define	DBC_ACTIVE	 0x0001		/* Cursor in use. */
#define	DBC_COMPENSATE	 0x0002		/* Cursor compensating, don't lock. */
#define