rec_btree

介绍：MySQL是比较出名的数据库软件

	if ((ret = memp_fget(mpf, &argp->pgno, 0, &pagep)) != 0)
		if (DB_REDO(op)) {
			if ((ret = memp_fget(mpf,
			    &argp->pgno, DB_MPOOL_CREATE, &pagep)) != 0)
				goto out;
		} else {
			*lsnp = argp->prev_lsn;
			ret = 0;
			goto out;
		}

	modified = 0;
	cmp_n = log_compare(lsnp, &LSN(pagep));

	/*
	 * Use this when there is something like "pagelsn" in the argp
	 * structure.  Sometimes, you might need to compare meta-data
	 * lsn's instead.
	 *
	 * cmp_p = log_compare(&LSN(pagep), argp->pagelsn);
	 */
	if (cmp_p == 0 && DB_REDO(op)) {
		/* Need to redo update described. */
		modified = 1;
	} else if (cmp_n == 0 && !DB_REDO(op)) {
		/* Need to undo update described. */
		modified = 1;
	}
	if (ret = memp_fput(mpf, pagep, modified ? DB_MPOOL_DIRTY : 0))
		goto out;

	*lsnp = argp->prev_lsn;
	ret = 0;

out:	REC_CLOSE;
}

/*
 * __bam_adj_recover --
 *	Recovery function for adj.
 *
 * PUBLIC: int __bam_adj_recover
 * PUBLIC:   __P((DB_ENV *, DBT *, DB_LSN *, db_recops, void *));
 */
int
__bam_adj_recover(dbenv, dbtp, lsnp, op, info)
	DB_ENV *dbenv;
	DBT *dbtp;
	DB_LSN *lsnp;
	db_recops op;
	void *info;
{
	__bam_adj_args *argp;
	DB *file_dbp;
	DBC *dbc;
	DB_MPOOLFILE *mpf;
	PAGE *pagep;
	int cmp_n, cmp_p, modified, ret;

	REC_PRINT(__bam_adj_print);
	REC_INTRO(__bam_adj_read);

	if ((ret = memp_fget(mpf, &argp->pgno, 0, &pagep)) != 0)
		if (DB_REDO(op)) {
			if ((ret = memp_fget(mpf,
			    &argp->pgno, DB_MPOOL_CREATE, &pagep)) != 0)
				goto out;
		} else {
			*lsnp = argp->prev_lsn;
			ret = 0;
			goto out;
		}

	modified = 0;
	cmp_n = log_compare(lsnp, &LSN(pagep));

	/*
	 * Use this when there is something like "pagelsn" in the argp
	 * structure.  Sometimes, you might need to compare meta-data
	 * lsn's instead.
	 *
	 * cmp_p = log_compare(&LSN(pagep), argp->pagelsn);
	 */
	if (cmp_p == 0 && DB_REDO(op)) {
		/* Need to redo update described. */
		modified = 1;
	} else if (cmp_n == 0 && !DB_REDO(op)) {
		/* Need to undo update described. */
		modified = 1;
	}
	if (ret = memp_fput(mpf, pagep, modified ? DB_MPOOL_DIRTY : 0))
		goto out;

	*lsnp = argp->prev_lsn;
	ret = 0;

out:	REC_CLOSE;
}

/*
 * __bam_cadjust_recover --
 *	Recovery function for cadjust.
 *
 * PUBLIC: int __bam_cadjust_recover
 * PUBLIC:   __P((DB_ENV *, DBT *, DB_LSN *, db_recops, void *));
 */
int
__bam_cadjust_recover(dbenv, dbtp, lsnp, op, info)
	DB_ENV *dbenv;
	DBT *dbtp;
	DB_LSN *lsnp;
	db_recops op;
	void *info;
{
	__bam_cadjust_args *argp;
	DB *file_dbp;
	DBC *dbc;
	DB_MPOOLFILE *mpf;
	PAGE *pagep;
	int cmp_n, cmp_p, modified, ret;

	REC_PRINT(__bam_cadjust_print);
	REC_INTRO(__bam_cadjust_read);

	if ((ret = memp_fget(mpf, &argp->pgno, 0, &pagep)) != 0)
		if (DB_REDO(op)) {
			if ((ret = memp_fget(mpf,
			    &argp->pgno, DB_MPOOL_CREATE, &pagep)) != 0)
				goto out;
		} else {
			*lsnp = argp->prev_lsn;
			ret = 0;
			goto out;
		}

	modified = 0;
	cmp_n = log_compare(lsnp, &LSN(pagep));

	/*
	 * Use this when there is something like "pagelsn" in the argp
	 * structure.  Sometimes, you might need to compare meta-data
	 * lsn's instead.
	 *
	 * cmp_p = log_compare(&LSN(pagep), argp->pagelsn);
	 */
	if (cmp_p == 0 && DB_REDO(op)) {
		/* Need to redo update described. */
		modified = 1;
	} else if (cmp_n == 0 && !DB_REDO(op)) {
		/* Need to undo update described. */
		modified = 1;
	}
	if (ret = memp_fput(mpf, pagep, modified ? DB_MPOOL_DIRTY : 0))
		goto out;

	*lsnp = argp->prev_lsn;
	ret = 0;

out:	REC_CLOSE;
}

/*
 * __bam_cdel_recover --
 *	Recovery function for cdel.
 *
 * PUBLIC: int __bam_cdel_recover
 * PUBLIC:   __P((DB_ENV *, DBT *, DB_LSN *, db_recops, void *));
 */
int
__bam_cdel_recover(dbenv, dbtp, lsnp, op, info)
	DB_ENV *dbenv;
	DBT *dbtp;
	DB_LSN *lsnp;
	db_recops op;
	void *info;
{
	__bam_cdel_args *argp;
	DB *file_dbp;
	DBC *dbc;
	DB_MPOOLFILE *mpf;
	PAGE *pagep;
	int cmp_n, cmp_p, modified, ret;

	REC_PRINT(__bam_cdel_print);
	REC_INTRO(__bam_cdel_read);

	if ((ret = memp_fget(mpf, &argp->pgno, 0, &pagep)) != 0)
		if (DB_REDO(op)) {
			if ((ret = memp_fget(mpf,
			    &argp->pgno, DB_MPOOL_CREATE, &pagep)) != 0)
				goto out;
		} else {
			*lsnp = argp->prev_lsn;
			ret = 0;
			goto out;
		}

	modified = 0;
	cmp_n = log_compare(lsnp, &LSN(pagep));

	/*
	 * Use this when there is something like "pagelsn" in the argp
	 * structure.  Sometimes, you might need to compare meta-data
	 * lsn's instead.
	 *
	 * cmp_p = log_compare(&LSN(pagep), argp->pagelsn);
	 */
	if (cmp_p == 0 && DB_REDO(op)) {
		/* Need to redo update described. */
		modified = 1;
	} else if (cmp_n == 0 && !DB_REDO(op)) {
		/* Need to undo update described. */
		modified = 1;
	}
	if (ret = memp_fput(mpf, pagep, modified ? DB_MPOOL_DIRTY : 0))
		goto out;

	*lsnp = argp->prev_lsn;
	ret = 0;

out:	REC_CLOSE;
}

/*
 * __bam_repl_recover --
 *	Recovery function for repl.
 *
 * PUBLIC: int __bam_repl_recover
 * PUBLIC:   __P((DB_ENV *, DBT *, DB_LSN *, db_recops, void *));
 */
int
__bam_repl_recover(dbenv, dbtp, lsnp, op, info)
	DB_ENV *dbenv;
	DBT *dbtp;
	DB_LSN *lsnp;
	db_recops op;
	void *info;
{
	__bam_repl_args *argp;
	DB *file_dbp;
	DBC *dbc;
	DB_MPOOLFILE *mpf;
	PAGE *pagep;
	int cmp_n, cmp_p, modified, ret;

	REC_PRINT(__bam_repl_print);
	REC_INTRO(__bam_repl_read);

	if ((ret = memp_fget(mpf, &argp->pgno, 0, &pagep)) != 0)
		if (DB_REDO(op)) {
			if ((ret = memp_fget(mpf,
			    &argp->pgno, DB_MPOOL_CREATE, &pagep)) != 0)
				goto out;
		} else {
			*lsnp = argp->prev_lsn;
			ret = 0;
			goto out;
		}

	modified = 0;
	cmp_n = log_compare(lsnp, &LSN(pagep));

	/*
	 * Use this when there is something like "pagelsn" in the argp
	 * structure.  Sometimes, you might need to compare meta-data
	 * lsn's instead.
	 *
	 * cmp_p = log_compare(&LSN(pagep), argp->pagelsn);
	 */
	if (cmp_p == 0 && DB_REDO(op)) {
		/* Need to redo update described. */
		modified = 1;
	} else if (cmp_n == 0 && !DB_REDO(op)) {
		/* Need to undo update described. */
		modified = 1;
	}
	if (ret = memp_fput(mpf, pagep, modified ? DB_MPOOL_DIRTY : 0))
		goto out;

	*lsnp = argp->prev_lsn;
	ret = 0;

out:	REC_CLOSE;
}

/*
 * __bam_root_recover --
 *	Recovery function for root.
 *
 * PUBLIC: int __bam_root_recover
 * PUBLIC:   __P((DB_ENV *, DBT *, DB_LSN *, db_recops, void *));
 */
int
__bam_root_recover(dbenv, dbtp, lsnp, op, info)
	DB_ENV *dbenv;
	DBT *dbtp;
	DB_LSN *lsnp;
	db_recops op;
	void *info;
{
	__bam_root_args *argp;
	DB *file_dbp;
	DBC *dbc;
	DB_MPOOLFILE *mpf;
	PAGE *pagep;
	int cmp_n, cmp_p, modified, ret;

	REC_PRINT(__bam_root_print);
	REC_INTRO(__bam_root_read);

	if ((ret = memp_fget(mpf, &argp->pgno, 0, &pagep)) != 0)
		if (DB_REDO(op)) {
			if ((ret = memp_fget(mpf,
			    &argp->pgno, DB_MPOOL_CREATE, &pagep)) != 0)
				goto out;
		} else {
			*lsnp = argp->prev_lsn;
			ret = 0;
			goto out;
		}

	modified = 0;
	cmp_n = log_compare(lsnp, &LSN(pagep));

	/*
	 * Use this when there is something like "pagelsn" in the argp
	 * structure.  Sometimes, you might need to compare meta-data
	 * lsn's instead.
	 *
	 * cmp_p = log_compare(&LSN(pagep), argp->pagelsn);
	 */
	if (cmp_p == 0 && DB_REDO(op)) {
		/* Need to redo update described. */
		modified = 1;
	} else if (cmp_n == 0 && !DB_REDO(op)) {
		/* Need to undo update described. */
		modified = 1;
	}
	if (ret = memp_fput(mpf, pagep, modified ? DB_MPOOL_DIRTY : 0))
		goto out;

	*lsnp = argp->prev_lsn;
	ret = 0;

out:	REC_CLOSE;
}

/*
 * __bam_curadj_recover --
 *	Recovery function for curadj.
 *
 * PUBLIC: int __bam_curadj_recover
 * PUBLIC:   __P((DB_ENV *, DBT *, DB_LSN *, db_recops, void *));
 */
int
__bam_curadj_recover(dbenv, dbtp, lsnp, op, info)
	DB_ENV *dbenv;
	DBT *dbtp;
	DB_LSN *lsnp;
	db_recops op;
	void *info;
{
	__bam_curadj_args *argp;
	DB *file_dbp;
	DBC *dbc;
	DB_MPOOLFILE *mpf;
	PAGE *pagep;
	int cmp_n, cmp_p, modified, ret;

	REC_PRINT(__bam_curadj_print);
	REC_INTRO(__bam_curadj_read);

	if ((ret = memp_fget(mpf, &argp->pgno, 0, &pagep)) != 0)
		if (DB_REDO(op)) {
			if ((ret = memp_fget(mpf,
			    &argp->pgno, DB_MPOOL_CREATE, &pagep)) != 0)
				goto out;
		} else {
			*lsnp = argp->prev_lsn;
			ret = 0;
			goto out;
		}

	modified = 0;
	cmp_n = log_compare(lsnp, &LSN(pagep));

	/*
	 * Use this when there is something like "pagelsn" in the argp
	 * structure.  Sometimes, you might need to compare meta-data
	 * lsn's instead.
	 *
	 * cmp_p = log_compare(&LSN(pagep), argp->pagelsn);
	 */
	if (cmp_p == 0 && DB_REDO(op)) {
		/* Need to redo update described. */
		modified = 1;
	} else if (cmp_n == 0 && !DB_REDO(op)) {
		/* Need to undo update described. */
		modified = 1;
	}
	if (ret = memp_fput(mpf, pagep, modified ? DB_MPOOL_DIRTY : 0))
		goto out;

	*lsnp = argp->prev_lsn;
	ret = 0;

out:	REC_CLOSE;
}

/*
 * __bam_rcuradj_recover --
 *	Recovery function for rcuradj.
 *
 * PUBLIC: int __bam_rcuradj_recover
 * PUBLIC:   __P((DB_ENV *, DBT *, DB_LSN *, db_recops, void *));
 */
int
__bam_rcuradj_recover(dbenv, dbtp, lsnp, op, info)
	DB_ENV *dbenv;
	DBT *dbtp;
	DB_LSN *lsnp;
	db_recops op;
	void *info;
{
	__bam_rcuradj_args *argp;
	DB *file_dbp;
	DBC *dbc;
	DB_MPOOLFILE *mpf;
	PAGE *pagep;
	int cmp_n, cmp_p, modified, ret;

	REC_PRINT(__bam_rcuradj_print);
	REC_INTRO(__bam_rcuradj_read);

	if ((ret = memp_fget(mpf, &argp->pgno, 0, &pagep)) != 0)
		if (DB_REDO(op)) {
			if ((ret = memp_fget(mpf,
			    &argp->pgno, DB_MPOOL_CREATE, &pagep)) != 0)
				goto out;
		} else {
			*lsnp = argp->prev_lsn;
			ret = 0;
			goto out;
		}

	modified = 0;
	cmp_n = log_compare(lsnp, &LSN(pagep));

	/*
	 * Use this when there is something like "pagelsn" in the argp
	 * structure.  Sometimes, you might need to compare meta-data
	 * lsn's instead.
	 *
	 * cmp_p = log_compare(&LSN(pagep), argp->pagelsn);
	 */
	if (cmp_p == 0 && DB_REDO(op)) {
		/* Need to redo update described. */
		modified = 1;
	} else if (cmp_n == 0 && !DB_REDO(op)) {
		/* Need to undo update described. */
		modified = 1;
	}
	if (ret = memp_fput(mpf, pagep, modified ? DB_MPOOL_DIRTY : 0))
		goto out;

	*lsnp = argp->prev_lsn;
	ret = 0;

out:	REC_CLOSE;
}