qam.c

这是linux下运行的mysql软件包,可用于linux 下安装 php + mysql + apach 的网络配置

/*-
 * See the file LICENSE for redistribution information.
 *
 * Copyright (c) 1999-2002
 *	Sleepycat Software.  All rights reserved.
 */

#include "db_config.h"

#ifndef lint
static const char revid[] = "$Id: qam.c,v 11.134 2002/08/13 20:46:08 ubell Exp $";
#endif /* not lint */

#ifndef NO_SYSTEM_INCLUDES
#include <sys/types.h>

#include <string.h>
#endif

#include "db_int.h"
#include "dbinc/db_page.h"
#include "dbinc/db_shash.h"
#include "dbinc/btree.h"
#include "dbinc/lock.h"
#include "dbinc/log.h"
#include "dbinc/qam.h"

static int __qam_bulk __P((DBC *, DBT *, u_int32_t));
static int __qam_c_close __P((DBC *, db_pgno_t, int *));
static int __qam_c_del __P((DBC *));
static int __qam_c_destroy __P((DBC *));
static int __qam_c_get __P((DBC *, DBT *, DBT *, u_int32_t, db_pgno_t *));
static int __qam_c_put __P((DBC *, DBT *, DBT *, u_int32_t, db_pgno_t *));
static int __qam_consume __P((DBC *, QMETA *, db_recno_t));
static int __qam_getno __P((DB *, const DBT *, db_recno_t *));

/*
 * __qam_position --
 *	Position a queued access method cursor at a record.  This returns
 *	the page locked.  *exactp will be set if the record is valid.
 * PUBLIC: int __qam_position
 * PUBLIC:       __P((DBC *, db_recno_t *, qam_position_mode, int *));
 */
int
__qam_position(dbc, recnop, mode, exactp)
	DBC *dbc;		/* open cursor */
	db_recno_t *recnop;	/* pointer to recno to find */
	qam_position_mode mode;/* locking: read or write */
	int *exactp;		/* indicate if it was found */
{
	QUEUE_CURSOR *cp;
	DB *dbp;
	QAMDATA  *qp;
	db_pgno_t pg;
	int ret;

	dbp = dbc->dbp;
	cp = (QUEUE_CURSOR *)dbc->internal;

	/* Fetch the page for this recno. */
	pg = QAM_RECNO_PAGE(dbp, *recnop);

	if ((ret = __db_lget(dbc, 0, pg, mode == QAM_READ ?
	    DB_LOCK_READ : DB_LOCK_WRITE, 0, &cp->lock)) != 0)
		return (ret);
	cp->page = NULL;
	*exactp = 0;
	if ((ret = __qam_fget(dbp, &pg,
	    mode == QAM_WRITE ? DB_MPOOL_CREATE : 0, &cp->page)) != 0) {
		/* We did not fetch it, we can release the lock. */
		(void)__LPUT(dbc, cp->lock);
		if (mode != QAM_WRITE &&
		    (ret == DB_PAGE_NOTFOUND || ret == ENOENT))
			return (0);
		return (ret);
	}
	cp->pgno = pg;
	cp->indx = QAM_RECNO_INDEX(dbp, pg, *recnop);

	if (PGNO(cp->page) == 0) {
		if (F_ISSET(dbp, DB_AM_RDONLY)) {
			*exactp = 0;
			return (0);
		}
		PGNO(cp->page) = pg;
		TYPE(cp->page) = P_QAMDATA;
	}

	qp = QAM_GET_RECORD(dbp, cp->page, cp->indx);
	*exactp = F_ISSET(qp, QAM_VALID) ? 1 : 0;

	return (ret);
}

/*
 * __qam_pitem --
 *	Put an item on a queue page.  Copy the data to the page and set the
 *	VALID and SET bits.  If logging and the record was previously set,
 *	log that data, otherwise just log the new data.
 *
 *   pagep must be write locked
 *
 * PUBLIC: int __qam_pitem
 * PUBLIC:     __P((DBC *,  QPAGE *, u_int32_t, db_recno_t, DBT *));
 */
int
__qam_pitem(dbc, pagep, indx, recno, data)
	DBC *dbc;
	QPAGE *pagep;
	u_int32_t indx;
	db_recno_t recno;
	DBT *data;
{
	DB *dbp;
	DBT olddata, pdata, *datap;
	QAMDATA *qp;
	QUEUE *t;
	u_int32_t alloced;
	u_int8_t *dest, *p;
	int ret;

	alloced = ret = 0;

	dbp = dbc->dbp;
	t = (QUEUE *)dbp->q_internal;

	if (data->size > t->re_len)
		goto len_err;

	qp = QAM_GET_RECORD(dbp, pagep, indx);

	p = qp->data;
	datap = data;
	if (F_ISSET(data, DB_DBT_PARTIAL)) {
		if (data->doff + data->dlen > t->re_len) {
			alloced = data->dlen;
			goto len_err;
		}
		if (data->size != data->dlen) {
len_err:		__db_err(dbp->dbenv,
			    "Length improper for fixed length record %lu",
			    (u_long)(alloced ? alloced : data->size));
			return (EINVAL);
		}
		if (data->size == t->re_len)
			goto no_partial;

		/*
		 * If we are logging, then we have to build the record
		 * first, otherwise, we can simply drop the change
		 * directly on the page.  After this clause, make
		 * sure that datap and p are set up correctly so that
		 * copying datap into p does the right thing.
		 *
		 * Note, I am changing this so that if the existing
		 * record is not valid, we create a complete record
		 * to log so that both this and the recovery code is simpler.
		 */

		if (DBC_LOGGING(dbc) || !F_ISSET(qp, QAM_VALID)) {
			datap = &pdata;
			memset(datap, 0, sizeof(*datap));

			if ((ret = __os_malloc(dbp->dbenv,
			    t->re_len, &datap->data)) != 0)
				return (ret);
			alloced = 1;
			datap->size = t->re_len;

			/*
			 * Construct the record if it's valid, otherwise set it
			 * all to the pad character.
			 */
			dest = datap->data;
			if (F_ISSET(qp, QAM_VALID))
				memcpy(dest, p, t->re_len);
			else
				memset(dest, t->re_pad, t->re_len);

			dest += data->doff;
			memcpy(dest, data->data, data->size);
		} else {
			datap = data;
			p += data->doff;
		}
	}

no_partial:
	if (DBC_LOGGING(dbc)) {
		olddata.size = 0;
		if (F_ISSET(qp, QAM_SET)) {
			olddata.data = qp->data;
			olddata.size = t->re_len;
		}
		if ((ret = __qam_add_log(dbp, dbc->txn, &LSN(pagep),
		    0, &LSN(pagep), pagep->pgno,
		    indx, recno, datap, qp->flags,
		    olddata.size == 0 ? NULL : &olddata)) != 0)
			goto err;
	}

	F_SET(qp, QAM_VALID | QAM_SET);
	memcpy(p, datap->data, datap->size);
	if (!F_ISSET(data, DB_DBT_PARTIAL))
		memset(p + datap->size,  t->re_pad, t->re_len - datap->size);

err:	if (alloced)
		__os_free(dbp->dbenv, datap->data);

	return (ret);
}
/*
 * __qam_c_put
 *	Cursor put for queued access method.
 *	BEFORE and AFTER cannot be specified.
 */
static int
__qam_c_put(dbc, key, data, flags, pgnop)
	DBC *dbc;
	DBT *key, *data;
	u_int32_t flags;
	db_pgno_t *pgnop;
{
	DB *dbp;
	DB_LOCK lock;
	DB_MPOOLFILE *mpf;
	QMETA *meta;
	QUEUE_CURSOR *cp;
	db_pgno_t pg;
	db_recno_t new_cur, new_first;
	u_int32_t opcode;
	int exact, ret, t_ret;

	dbp = dbc->dbp;
	mpf = dbp->mpf;
	if (pgnop != NULL)
		*pgnop = PGNO_INVALID;

	cp = (QUEUE_CURSOR *)dbc->internal;

	switch (flags) {
	case DB_KEYFIRST:
	case DB_KEYLAST:
		if ((ret = __qam_getno(dbp, key, &cp->recno)) != 0)
			return (ret);
		/* FALLTHROUGH */
	case DB_CURRENT:
		break;
	default:
		/* The interface shouldn't let anything else through. */
		DB_ASSERT(0);
		return (__db_ferr(dbp->dbenv, "__qam_c_put", flags));
	}

	/* Write lock the record. */
	if ((ret = __db_lget(dbc,
	    0, cp->recno, DB_LOCK_WRITE, DB_LOCK_RECORD, &lock)) != 0)
		return (ret);

	if ((ret = __qam_position(dbc,
	    &cp->recno, QAM_WRITE, &exact)) != 0) {
		/* We could not get the page, we can release the record lock. */
		__LPUT(dbc, lock);
		return (ret);
	}

	/* Put the item on the page. */
	ret = __qam_pitem(dbc, (QPAGE *)cp->page, cp->indx, cp->recno, data);

	/* Doing record locking, release the page lock */
	if ((t_ret = __LPUT(dbc, cp->lock)) != 0 && ret == 0)
		ret = t_ret;
	if ((t_ret = __qam_fput(
	    dbp, cp->pgno, cp->page, DB_MPOOL_DIRTY)) != 0 && ret == 0)
		ret = t_ret;
	cp->page = NULL;
	cp->lock = lock;
	cp->lock_mode = DB_LOCK_WRITE;
	if (ret != 0)
		return (ret);

	/* We may need to reset the head or tail of the queue. */
	pg = ((QUEUE *)dbp->q_internal)->q_meta;

	/*
	 * Get the meta page first, we don't want to write lock it while
	 * trying to pin it.
	 */
	if ((ret = mpf->get(mpf, &pg, 0, &meta)) != 0)
		return (ret);
	if ((ret = __db_lget(dbc, 0, pg,  DB_LOCK_WRITE, 0, &lock)) != 0) {
		(void)mpf->put(mpf, meta, 0);
		return (ret);
	}

	opcode = 0;
	new_cur = new_first = 0;

	/*
	 * If the put address is outside the queue, adjust the head and
	 * tail of the queue.  If the order is inverted we move
	 * the one which is closer.  The first case is when the
	 * queue is empty, move first and current to where the new
	 * insert is.
	 */

	if (meta->first_recno == meta->cur_recno) {
		new_first = cp->recno;
		new_cur = cp->recno + 1;
		if (new_cur == RECNO_OOB)
			new_cur++;
		opcode |= QAM_SETFIRST;
		opcode |= QAM_SETCUR;
	} else {
		if (QAM_BEFORE_FIRST(meta, cp->recno) &&
		    (meta->first_recno <= meta->cur_recno ||
		    meta->first_recno - cp->recno <
		    cp->recno - meta->cur_recno)) {
			new_first = cp->recno;
			opcode |= QAM_SETFIRST;
		}

		if (meta->cur_recno == cp->recno ||
		    (QAM_AFTER_CURRENT(meta, cp->recno) &&
		    (meta->first_recno <= meta->cur_recno ||
		    cp->recno - meta->cur_recno <=
		    meta->first_recno - cp->recno))) {
			new_cur = cp->recno + 1;
			if (new_cur == RECNO_OOB)
				new_cur++;
			opcode |= QAM_SETCUR;
		}
	}

	if (opcode != 0 && DBC_LOGGING(dbc)) {
		ret = __qam_mvptr_log(dbp, dbc->txn, &meta->dbmeta.lsn,
		    0, opcode, meta->first_recno, new_first,
		    meta->cur_recno, new_cur, &meta->dbmeta.lsn, PGNO_BASE_MD);
		if (ret != 0)
			opcode = 0;
	}

	if (opcode & QAM_SETCUR)
		meta->cur_recno = new_cur;
	if (opcode & QAM_SETFIRST)
		meta->first_recno = new_first;

	if ((t_ret = mpf->put(
	    mpf, meta, opcode != 0 ? DB_MPOOL_DIRTY : 0)) != 0 && ret == 0)
		ret = t_ret;

	/* Don't hold the meta page long term. */
	if ((t_ret = __LPUT(dbc, lock)) != 0 && ret == 0)
		ret = t_ret;
	return (ret);
}

/*
 * __qam_append --
 *	Perform a put(DB_APPEND) in queue.
 *
 * PUBLIC: int __qam_append __P((DBC *, DBT *, DBT *));
 */
int
__qam_append(dbc, key, data)
	DBC *dbc;
	DBT *key, *data;
{
	DB *dbp;
	DB_LOCK lock;
	DB_MPOOLFILE *mpf;
	QMETA *meta;
	QPAGE *page;
	QUEUE *qp;
	QUEUE_CURSOR *cp;
	db_pgno_t pg;
	db_recno_t recno;
	int ret, t_ret;

	dbp = dbc->dbp;
	mpf = dbp->mpf;
	cp = (QUEUE_CURSOR *)dbc->internal;

	pg = ((QUEUE *)dbp->q_internal)->q_meta;
	/*
	 * Get the meta page first, we don't want to write lock it while
	 * trying to pin it.
	 */
	if ((ret = mpf->get(mpf, &pg, 0, &meta)) != 0)
		return (ret);
	/* Write lock the meta page. */
	if ((ret = __db_lget(dbc, 0, pg,  DB_LOCK_WRITE, 0, &lock)) != 0) {
		(void)mpf->put(mpf, meta, 0);
		return (ret);
	}

	/* Get the next record number. */
	recno = meta->cur_recno;
	meta->cur_recno++;
	if (meta->cur_recno == RECNO_OOB)
		meta->cur_recno++;
	if (meta->cur_recno == meta->first_recno) {
		meta->cur_recno--;
		if (meta->cur_recno == RECNO_OOB)
			meta->cur_recno--;
		(void)__LPUT(dbc, lock);
		ret = EFBIG;
		goto err;
	}

	if (QAM_BEFORE_FIRST(meta, recno))
		meta->first_recno = recno;

	/* Lock the record and release meta page lock. */
	if ((ret = __db_lget(dbc, LCK_COUPLE_ALWAYS,
	    recno, DB_LOCK_WRITE, DB_LOCK_RECORD, &lock)) != 0) {
		(void)__LPUT(dbc, lock);
		goto err;
	}

	/*
	 * The application may modify the data based on the selected record
	 * number.
	 */
	if (dbc->dbp->db_append_recno != NULL &&
	    (ret = dbc->dbp->db_append_recno(dbc->dbp, data, recno)) != 0) {
		(void)__LPUT(dbc, lock);
		goto err;
	}

	cp->lock = lock;
	cp->lock_mode = DB_LOCK_WRITE;

	pg = QAM_RECNO_PAGE(dbp, recno);

	/* Fetch and write lock the data page. */
	if ((ret = __db_lget(dbc, 0, pg,  DB_LOCK_WRITE, 0, &lock)) != 0)
		goto err;
	if ((ret = __qam_fget(dbp, &pg, DB_MPOOL_CREATE, &page)) != 0) {
		/* We did not fetch it, we can release the lock. */
		(void)__LPUT(dbc, lock);
		goto err;
	}

	/* See if this is a new page. */
	if (page->pgno == 0) {
		page->pgno = pg;
		page->type = P_QAMDATA;
	}

	/* Put the item on the page and log it. */
	ret = __qam_pitem(dbc, page,
	    QAM_RECNO_INDEX(dbp, pg, recno), recno, data);

	/* Doing record locking, release the page lock */
	if ((t_ret = __LPUT(dbc, lock)) != 0 && ret == 0)
		ret = t_ret;

	if ((t_ret
	    = __qam_fput(dbp, pg, page, DB_MPOOL_DIRTY)) != 0 && ret == 0)
		ret = t_ret;

	/* Return the record number to the user. */
	if (ret == 0)
		ret = __db_retcopy(dbp->dbenv, key,
		    &recno, sizeof(recno), &dbc->rkey->data, &dbc->rkey->ulen);

	/* Position the cursor on this record. */
	cp->recno = recno;

	/* See if we are leaving the extent. */
	qp = (QUEUE *) dbp->q_internal;
	if (qp->page_ext != 0 &&
	    (recno % (qp->page_ext * qp->rec_page) == 0 ||
	    recno == UINT32_T_MAX)) {
		if ((ret = __db_lget(dbc,
		    0, ((QUEUE *)dbp->q_internal)->q_meta,
		    DB_LOCK_WRITE, 0, &lock)) != 0)
			goto err;
		if (!QAM_AFTER_CURRENT(meta, recno))
			ret = __qam_fclose(dbp, pg);
		(void)__LPUT(dbc, lock);
	}

err:
	/* Release the meta page. */
	if ((t_ret = mpf->put(mpf, meta, DB_MPOOL_DIRTY)) != 0 && ret == 0)
		ret = t_ret;

	return (ret);
}

/*
 * __qam_c_del --
 *	Qam cursor->am_del function
 */
static int
__qam_c_del(dbc)
	DBC *dbc;
{
	DB *dbp;
	DBT data;
	DB_LOCK lock;
	DB_MPOOLFILE *mpf;
	PAGE *pagep;
	QAMDATA *qp;
	QMETA *meta;
	QUEUE_CURSOR *cp;
	db_pgno_t pg;
	db_recno_t first;
	int exact, ret, t_ret;

	dbp = dbc->dbp;
	mpf = dbp->mpf;
	cp = (QUEUE_CURSOR *)dbc->internal;

	pg = ((QUEUE *)dbp->q_internal)->q_meta;
	/*
	 * Get the meta page first, we don't want to write lock it while
	 * trying to pin it.
	 */
	if ((ret = mpf->get(mpf, &pg, 0, &meta)) != 0)
		return (ret);
	/* Write lock the meta page. */
	if ((ret = __db_lget(dbc, 0, pg,  DB_LOCK_READ, 0, &lock)) != 0) {
		(void)mpf->put(mpf, meta, 0);
		return (ret);
	}

	if (QAM_NOT_VALID(meta, cp->recno))
		ret = DB_NOTFOUND;

	first = meta->first_recno;

	/* Don't hold the meta page long term. */
	if ((t_ret = __LPUT(dbc, lock)) != 0 && ret == 0)
		ret = t_ret;

	if (ret != 0)