hash_page.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

			end = (u_int8_t *)tdata.data + tdata.size;

			src = (u_int8_t *)tdata.data + dbt->doff + dbt->dlen;
			if (src < end && tdata.size > dbt->doff + dbt->dlen) {
				len = tdata.size - dbt->doff - dbt->dlen;
				dest = src + change;
				memmove(dest, src, len);
			}
			memcpy((u_int8_t *)tdata.data + dbt->doff,
			    dbt->data, dbt->size);
			tdata.size += change;

			/* Now add the pair. */
			ret = __ham_add_el(dbc, &tmp, &tdata, type);
			__os_free(dbenv, memp);
		}
		F_SET(hcp, dup_flag);
err:		return (ret);
	}

	/*
	 * Set up pointer into existing data. Do it before the log
	 * message so we can use it inside of the log setup.
	 */
	beg = HKEYDATA_DATA(H_PAIRDATA(dbp, hcp->page, hcp->indx));
	beg += dbt->doff;

	/*
	 * If we are going to have to move bytes at all, figure out
	 * all the parameters here.  Then log the call before moving
	 * anything around.
	 */
	if (DBC_LOGGING(dbc)) {
		old_dbt.data = beg;
		old_dbt.size = dbt->dlen;
		if ((ret = __ham_replace_log(dbp,
		    dbc->txn, &new_lsn, 0, PGNO(hcp->page),
		    (u_int32_t)H_DATAINDEX(hcp->indx), &LSN(hcp->page),
		    (u_int32_t)dbt->doff, &old_dbt, dbt, make_dup)) != 0)
			return (ret);

	} else
		LSN_NOT_LOGGED(new_lsn);

	LSN(hcp->page) = new_lsn;	/* Structure assignment. */

	__ham_onpage_replace(dbp, hcp->page, (u_int32_t)H_DATAINDEX(hcp->indx),
	    (int32_t)dbt->doff, change, dbt);

	return (0);
}

/*
 * Replace data on a page with new data, possibly growing or shrinking what's
 * there.  This is called on two different occasions. On one (from replpair)
 * we are interested in changing only the data.  On the other (from recovery)
 * we are replacing the entire data (header and all) with a new element.  In
 * the latter case, the off argument is negative.
 * pagep: the page that we're changing
 * ndx: page index of the element that is growing/shrinking.
 * off: Offset at which we are beginning the replacement.
 * change: the number of bytes (+ or -) that the element is growing/shrinking.
 * dbt: the new data that gets written at beg.
 *
 * PUBLIC: void __ham_onpage_replace __P((DB *, PAGE *, u_int32_t,
 * PUBLIC:     int32_t, int32_t,  DBT *));
 */
void
__ham_onpage_replace(dbp, pagep, ndx, off, change, dbt)
	DB *dbp;
	PAGE *pagep;
	u_int32_t ndx;
	int32_t off;
	int32_t change;
	DBT *dbt;
{
	db_indx_t i, *inp;
	int32_t len;
	size_t pgsize;
	u_int8_t *src, *dest;
	int zero_me;

	pgsize = dbp->pgsize;
	inp = P_INP(dbp, pagep);
	if (change != 0) {
		zero_me = 0;
		src = (u_int8_t *)(pagep) + HOFFSET(pagep);
		if (off < 0)
			len = inp[ndx] - HOFFSET(pagep);
		else if ((u_int32_t)off >=
		    LEN_HKEYDATA(dbp, pagep, pgsize, ndx)) {
			len = (int32_t)(HKEYDATA_DATA(P_ENTRY(dbp, pagep, ndx))
			    + LEN_HKEYDATA(dbp, pagep, pgsize, ndx) - src);
			zero_me = 1;
		} else
			len = (int32_t)(
			    (HKEYDATA_DATA(P_ENTRY(dbp, pagep, ndx)) + off) -
			    src);
		dest = src - change;
		memmove(dest, src, len);
		if (zero_me)
			memset(dest + len, 0, change);

		/* Now update the indices. */
		for (i = ndx; i < NUM_ENT(pagep); i++)
			inp[i] -= change;
		HOFFSET(pagep) -= change;
	}
	if (off >= 0)
		memcpy(HKEYDATA_DATA(P_ENTRY(dbp, pagep, ndx)) + off,
		    dbt->data, dbt->size);
	else
		memcpy(P_ENTRY(dbp, pagep, ndx), dbt->data, dbt->size);
}

/*
 * PUBLIC: int __ham_split_page __P((DBC *, u_int32_t, u_int32_t));
 */
int
__ham_split_page(dbc, obucket, nbucket)
	DBC *dbc;
	u_int32_t obucket, nbucket;
{
	DB *dbp;
	DBC **carray;
	DBT key, page_dbt;
	DB_ENV *dbenv;
	DB_LOCK block;
	DB_LSN new_lsn;
	DB_MPOOLFILE *mpf;
	HASH_CURSOR *hcp, *cp;
	PAGE **pp, *old_pagep, *temp_pagep, *new_pagep;
	db_indx_t n;
	db_pgno_t bucket_pgno, npgno, next_pgno;
	u_int32_t big_len, len;
	int found, i, ret, t_ret;
	void *big_buf;

	dbp = dbc->dbp;
	dbenv = dbp->dbenv;
	mpf = dbp->mpf;
	hcp = (HASH_CURSOR *)dbc->internal;
	temp_pagep = old_pagep = new_pagep = NULL;
	carray = NULL;
	LOCK_INIT(block);

	bucket_pgno = BUCKET_TO_PAGE(hcp, obucket);
	if ((ret = __db_lget(dbc,
	    0, bucket_pgno, DB_LOCK_WRITE, 0, &block)) != 0)
		goto err;
	if ((ret = mpf->get(mpf,
	    &bucket_pgno, DB_MPOOL_CREATE, &old_pagep)) != 0)
		goto err;

	/* Properly initialize the new bucket page. */
	npgno = BUCKET_TO_PAGE(hcp, nbucket);
	if ((ret = mpf->get(mpf, &npgno, DB_MPOOL_CREATE, &new_pagep)) != 0)
		goto err;
	P_INIT(new_pagep,
	    dbp->pgsize, npgno, PGNO_INVALID, PGNO_INVALID, 0, P_HASH);

	temp_pagep = hcp->split_buf;
	memcpy(temp_pagep, old_pagep, dbp->pgsize);

	if (DBC_LOGGING(dbc)) {
		page_dbt.size = dbp->pgsize;
		page_dbt.data = old_pagep;
		if ((ret = __ham_splitdata_log(dbp,
		    dbc->txn, &new_lsn, 0, SPLITOLD,
		    PGNO(old_pagep), &page_dbt, &LSN(old_pagep))) != 0)
			goto err;
	} else
		LSN_NOT_LOGGED(new_lsn);

	LSN(old_pagep) = new_lsn;	/* Structure assignment. */

	P_INIT(old_pagep, dbp->pgsize, PGNO(old_pagep), PGNO_INVALID,
	    PGNO_INVALID, 0, P_HASH);

	big_len = 0;
	big_buf = NULL;
	key.flags = 0;
	while (temp_pagep != NULL) {
		if ((ret = __ham_get_clist(dbp,
		    PGNO(temp_pagep), NDX_INVALID, &carray)) != 0)
			goto err;

		for (n = 0; n < (db_indx_t)NUM_ENT(temp_pagep); n += 2) {
			if ((ret = __db_ret(dbp, temp_pagep,
			    H_KEYINDEX(n), &key, &big_buf, &big_len)) != 0)
				goto err;

			if (__ham_call_hash(dbc, key.data, key.size) == obucket)
				pp = &old_pagep;
			else
				pp = &new_pagep;

			/*
			 * Figure out how many bytes we need on the new
			 * page to store the key/data pair.
			 */
			len = LEN_HITEM(dbp, temp_pagep, dbp->pgsize,
			    H_DATAINDEX(n)) +
			    LEN_HITEM(dbp, temp_pagep, dbp->pgsize,
			    H_KEYINDEX(n)) +
			    2 * sizeof(db_indx_t);

			if (P_FREESPACE(dbp, *pp) < len) {
				if (DBC_LOGGING(dbc)) {
					page_dbt.size = dbp->pgsize;
					page_dbt.data = *pp;
					if ((ret = __ham_splitdata_log(dbp,
					    dbc->txn, &new_lsn, 0,
					    SPLITNEW, PGNO(*pp), &page_dbt,
					    &LSN(*pp))) != 0)
						goto err;
				} else
					LSN_NOT_LOGGED(new_lsn);
				LSN(*pp) = new_lsn;
				if ((ret =
				    __ham_add_ovflpage(dbc, *pp, 1, pp)) != 0)
					goto err;
			}

			/* Check if we need to update a cursor. */
			if (carray != NULL) {
				found = 0;
				for (i = 0; carray[i] != NULL; i++) {
					cp =
					    (HASH_CURSOR *)carray[i]->internal;
					if (cp->pgno == PGNO(temp_pagep) &&
					    cp->indx == n) {
						cp->pgno = PGNO(*pp);
						cp->indx = NUM_ENT(*pp);
						found = 1;
					}
				}
				if (found && DBC_LOGGING(dbc) &&
				    IS_SUBTRANSACTION(dbc->txn)) {
					if ((ret =
					    __ham_chgpg_log(dbp,
					    dbc->txn, &new_lsn, 0,
					    DB_HAM_SPLIT, PGNO(temp_pagep),
					    PGNO(*pp), n, NUM_ENT(*pp))) != 0)
						goto err;
				}
			}
			__ham_copy_item(dbp, temp_pagep, H_KEYINDEX(n), *pp);
			__ham_copy_item(dbp, temp_pagep, H_DATAINDEX(n), *pp);
		}
		next_pgno = NEXT_PGNO(temp_pagep);

		/* Clear temp_page; if it's a link overflow page, free it. */
		if (PGNO(temp_pagep) != bucket_pgno && (ret =
		    __db_free(dbc, temp_pagep)) != 0) {
			temp_pagep = NULL;
			goto err;
		}

		if (next_pgno == PGNO_INVALID)
			temp_pagep = NULL;
		else if ((ret = mpf->get(
		    mpf, &next_pgno, DB_MPOOL_CREATE, &temp_pagep)) != 0)
			goto err;

		if (temp_pagep != NULL) {
			if (DBC_LOGGING(dbc)) {
				page_dbt.size = dbp->pgsize;
				page_dbt.data = temp_pagep;
				if ((ret = __ham_splitdata_log(dbp,
				    dbc->txn, &new_lsn, 0,
				    SPLITOLD, PGNO(temp_pagep),
				    &page_dbt, &LSN(temp_pagep))) != 0)
					goto err;
			} else
				LSN_NOT_LOGGED(new_lsn);
			LSN(temp_pagep) = new_lsn;
		}

		if (carray != NULL)	/* We never knew its size. */
			__os_free(dbenv, carray);
		carray = NULL;
	}
	if (big_buf != NULL)
		__os_free(dbenv, big_buf);

	/*
	 * If the original bucket spanned multiple pages, then we've got
	 * a pointer to a page that used to be on the bucket chain.  It
	 * should be deleted.
	 */
	if (temp_pagep != NULL && PGNO(temp_pagep) != bucket_pgno &&
	    (ret = __db_free(dbc, temp_pagep)) != 0) {
		temp_pagep = NULL;
		goto err;
	}

	/*
	 * Write new buckets out.
	 */
	if (DBC_LOGGING(dbc)) {
		page_dbt.size = dbp->pgsize;
		page_dbt.data = old_pagep;
		if ((ret = __ham_splitdata_log(dbp, dbc->txn,
		    &new_lsn, 0, SPLITNEW, PGNO(old_pagep), &page_dbt,
		    &LSN(old_pagep))) != 0)
			goto err;
		LSN(old_pagep) = new_lsn;

		page_dbt.data = new_pagep;
		if ((ret = __ham_splitdata_log(dbp, dbc->txn, &new_lsn, 0,
		    SPLITNEW, PGNO(new_pagep), &page_dbt,
		    &LSN(new_pagep))) != 0)
			goto err;
		LSN(new_pagep) = new_lsn;
	} else {
		LSN_NOT_LOGGED(LSN(old_pagep));
		LSN_NOT_LOGGED(LSN(new_pagep));
	}

	ret = mpf->put(mpf, old_pagep, DB_MPOOL_DIRTY);
	if ((t_ret =
	    mpf->put(mpf, new_pagep, DB_MPOOL_DIRTY)) != 0 && ret == 0)
		ret = t_ret;

	if (0) {
err:		if (old_pagep != NULL)
			(void)mpf->put(mpf, old_pagep, DB_MPOOL_DIRTY);
		if (new_pagep != NULL)
			(void)mpf->put(mpf, new_pagep, DB_MPOOL_DIRTY);
		if (temp_pagep != NULL && PGNO(temp_pagep) != bucket_pgno)
			(void)mpf->put(mpf, temp_pagep, DB_MPOOL_DIRTY);
	}
	if (LOCK_ISSET(block))
		__TLPUT(dbc, block);
	if (carray != NULL)		/* We never knew its size. */
		__os_free(dbenv, carray);
	return (ret);
}

/*
 * Add the given pair to the page.  The page in question may already be
 * held (i.e. it was already gotten).  If it is, then the page is passed
 * in via the pagep parameter.  On return, pagep will contain the page
 * to which we just added something.  This allows us to link overflow
 * pages and return the new page having correctly put the last page.
 *
 * PUBLIC: int __ham_add_el __P((DBC *, const DBT *, const DBT *, int));
 */
int
__ham_add_el(dbc, key, val, type)
	DBC *dbc;
	const DBT *key, *val;
	int type;
{
	const DBT *pkey, *pdata;
	DB *dbp;
	DBT key_dbt, data_dbt;
	DB_LSN new_lsn;
	DB_MPOOLFILE *mpf;
	HASH_CURSOR *hcp;
	HOFFPAGE doff, koff;
	db_pgno_t next_pgno, pgno;
	u_int32_t data_size, key_size, pairsize, rectype;
	int do_expand, is_keybig, is_databig, ret;
	int key_type, data_type;

	dbp = dbc->dbp;
	mpf = dbp->mpf;
	hcp = (HASH_CURSOR *)dbc->internal;
	do_expand = 0;

	pgno = hcp->seek_found_page != PGNO_INVALID ?
	    hcp->seek_found_page : hcp->pgno;
	if (hcp->page == NULL &&
	    (ret = mpf->get(mpf, &pgno, DB_MPOOL_CREATE, &hcp->page)) != 0)
		return (ret);

	key_size = HKEYDATA_PSIZE(key->size);
	data_size = HKEYDATA_PSIZE(val->size);
	is_keybig = ISBIG(hcp, key->size);
	is_databig = ISBIG(hcp, val->size);
	if (is_keybig)
		key_size = HOFFPAGE_PSIZE;
	if (is_databig)
		data_size = HOFFPAGE_PSIZE;

	pairsize = key_size + data_size;

	/* Advance to first page in chain with room for item. */
	while (H_NUMPAIRS(hcp->page) && NEXT_PGNO(hcp->page) != PGNO_INVALID) {
		/*
		 * This may not be the end of the chain, but the pair may fit
		 * anyway.  Check if it's a bigpair that fits or a regular
		 * pair that fits.
		 */
		if (P_FREESPACE(dbp, hcp->page) >= pairsize)
			break;
		next_pgno = NEXT_PGNO(hcp->page);
		if ((ret = __ham_next_cpage(dbc, next_pgno, 0)) != 0)
			return (ret);
	}

	/*
	 * Check if we need to allocate a new page.
	 */
	if (P_FREESPACE(dbp, hcp->page) < pairsize) {
		do_expand = 1;
		if ((ret = __ham_add_ovflpage(dbc,
		    (PAGE *)hcp->page, 1, (PAGE **)&hcp->page)) != 0)
			return (ret);
		hcp->pgno = PGNO(hcp->page);
	}

	/*
	 * Update cursor.
	 */
	hcp->indx = NUM_ENT(hcp->page);
	F_CLR(hcp, H_DELETED);
	if (is_keybig) {
		koff.type = H_OFFPAGE;
		UMRW_SET(koff.unused[0]);
		UMRW_SET(koff.unused[1]);
		UMRW_SET(koff.unused[2]);
		if ((ret = __db_poff(dbc, key, &koff.pgno)) != 0)
			return (ret);
		koff.tlen = key->size;
		key_dbt.data = &koff;
		key_dbt.size = sizeof(koff);
		pkey = &key_dbt;
		key_type = H_OFFPAGE;
	} else {
		pkey = key;
		key_type = H_KEYDATA;
	}

	if (is_databig) {
		doff.type = H_OFFPAGE;
		UMRW_SET(doff.unused[0]);
		UMRW_SET(doff.unused[1]);
		UMRW_SET(doff.unused[2]);
		if ((ret = __db_poff(dbc, val, &doff.pgno)) != 0)
			return (ret);
		doff.tlen = val->size;
		data_dbt.data = &doff;
		data_dbt.size = sizeof(doff);
		pdata = &data_dbt;
		data_type = H_OFFPAGE;
	} else {
		pdata = val;
		data_type = type;
	}

	if (DBC_LOGGING(dbc)) {
		rectype = PUTPAIR;
		if (is_databig)
			rectype |= PAIR_DATAMASK;
		if (is_keybig)
			rectype |= PAIR_KEYMASK;
		if (type == H_DUPLICATE)
			rectype |= PAIR_DUPMASK;

		if ((ret = __ham_insdel_log(dbp, dbc->txn, &new_lsn, 0,
		    rectype, PGNO(hcp->page), (u_int32_t)NUM_ENT(hcp->page),
		    &LSN(hcp->page), pkey, pdata)) != 0)
			return (ret);