branches/innodb+: row_search_index_entry(): Clean up the call interface

and add assertions to callers.  Remove the added ibool* parameter and
return enum row_search_result instead of ibool, to reflect the four
different outcomes: record found, not found, buffered, and status unknown
(record not in the buffer pool).

rb://6

include/row0row.h

@@ -261,16 +261,28 @@ row_get_clust_rec(
 	dict_index_t*	index,	/* in: secondary index */
 	dict_index_t**	clust_index,/* out: clustered index */
 	mtr_t*		mtr);	/* in: mtr */
+
+/* Result of row_search_index_entry */
+enum row_search_result {
+	ROW_FOUND = 0,		/* the record was found */
+	ROW_NOT_FOUND,		/* record not found */
+	ROW_BUFFERED,		/* one of BTR_INSERT, BTR_DELETE, or
+				BTR_DELETE_MARK was specified, the
+				secondary index leaf page was not in
+				the buffer pool, and the operation was
+				enqueued in the insert/delete buffer */
+	ROW_NOT_IN_POOL		/* BTR_WATCH_LEAF was specified and the
+				record was not in the buffer pool */
+};
+
 /*******************************************************************
 Searches an index record. */
 UNIV_INTERN
-ibool
+enum row_search_result
 row_search_index_entry(
 /*===================*/
-				/* out: TRUE if found */
-	ibool*		was_buffered,
-				/* out: TRUE if the operation was buffered
-				in the insert/delete buffer. Can be NULL. */
+				/* out: whether the record was found
+				or buffered */
 	dict_index_t*	index,	/* in: index */
 	const dtuple_t*	entry,	/* in: index entry */
 	ulint		mode,	/* in: BTR_MODIFY_LEAF, ... */

row/row0purge.c

@@ -211,30 +211,41 @@ row_purge_remove_sec_if_poss_low_nonbuffered(
 	ulint		mode)	/* in: latch mode BTR_MODIFY_LEAF or
 				BTR_MODIFY_TREE */
 {
-	btr_pcur_t	pcur;
-	btr_cur_t*	btr_cur;
-	ibool		success;
-	ibool		old_has = FALSE; /* remove warning */
-	ibool		found;
-	ulint		err;
-	mtr_t		mtr;
-	mtr_t*		mtr_vers;
+	btr_pcur_t		pcur;
+	btr_cur_t*		btr_cur;
+	ibool			success;
+	ibool			old_has = FALSE;
+	ulint			err;
+	mtr_t			mtr;
+	mtr_t*			mtr_vers;
+	enum row_search_result	search_result;
 
 	log_free_check();
 	mtr_start(&mtr);
 
-	found = row_search_index_entry(NULL, index, entry, mode, &pcur, &mtr);
+	ut_ad(mode == BTR_MODIFY_TREE || mode == BTR_MODIFY_LEAF);
 
-	if (!found) {
+	search_result = row_search_index_entry(index, entry, mode,
+					       &pcur, &mtr);
+
+	switch (search_result) {
+	case ROW_NOT_FOUND:
 		/* Not found */
 
 		/* fputs("PURGE:........sec entry not found\n", stderr); */
-		/* dtuple_print(entry); */
-
-		btr_pcur_close(&pcur);
-		mtr_commit(&mtr);
-
-		return(TRUE);
+		/* dtuple_print(stderr, entry); */
+
+		success = TRUE;
+		goto func_exit;
+	case ROW_FOUND:
+		break;
+	case ROW_BUFFERED:
+	case ROW_NOT_IN_POOL:
+		/* These are invalid outcomes, because the mode passed
+		to row_search_index_entry() did not include any of the
+		flags BTR_INSERT, BTR_DELETE, BTR_DELETE_MARK, or
+		BTR_WATCH_LEAF. */
+		ut_error;
 	}
 
 	btr_cur = btr_pcur_get_btr_cur(&pcur);
@@ -259,7 +270,7 @@ row_purge_remove_sec_if_poss_low_nonbuffered(
 
 	mem_free(mtr_vers);
 
-	if (!success || !old_has) {
+	if (!old_has) {
 		/* Remove the index record */
 
 		if (mode == BTR_MODIFY_LEAF) {
@@ -273,6 +284,7 @@ row_purge_remove_sec_if_poss_low_nonbuffered(
 		}
 	}
 
+func_exit:
 	btr_pcur_close(&pcur);
 	mtr_commit(&mtr);
 
@@ -292,65 +304,64 @@ row_purge_remove_sec_if_poss_low(
 	ulint		mode)	/* in: latch mode BTR_MODIFY_LEAF or
 				BTR_MODIFY_TREE */
 {
-	mtr_t		mtr;
-	btr_pcur_t	pcur;
-	btr_cur_t*	btr_cur;
-	ibool		found;
-	ibool		success;
-	ibool		was_buffered;
-	ibool		old_has = FALSE;
-	ibool		leaf_in_buf_pool;
-
-	ut_a((mode == BTR_MODIFY_TREE) || (mode == BTR_MODIFY_LEAF));
+	mtr_t			mtr;
+	btr_pcur_t		pcur;
+#ifdef UNIV_DEBUG
+	ibool			leaf_in_buf_pool;
+#endif /* UNIV_DEBUG */
+	ibool			old_has	= FALSE;
+	enum row_search_result	search_result;
 
 	if (mode == BTR_MODIFY_TREE) {
 		/* Can't use the insert/delete buffer if we potentially
 		need to split pages. */
-
-		return(row_purge_remove_sec_if_poss_low_nonbuffered(
-			       node, index, entry, mode));
+		goto unbuffered;
 	}
 
+	ut_ad(mode == BTR_MODIFY_LEAF);
+
 	log_free_check();
 
 	mtr_start(&mtr);
 
-	found = row_search_index_entry(
-		NULL, index, entry,
-		BTR_SEARCH_LEAF | BTR_WATCH_LEAF, &pcur, &mtr);
+	search_result = row_search_index_entry(
+		index, entry, BTR_SEARCH_LEAF | BTR_WATCH_LEAF, &pcur, &mtr);
 
-	btr_cur = btr_pcur_get_btr_cur(&pcur);
-	leaf_in_buf_pool = btr_cur->leaf_in_buf_pool;
-
-	ut_a(!found || leaf_in_buf_pool);
+	ut_d(leaf_in_buf_pool = btr_pcur_get_btr_cur(&pcur)->leaf_in_buf_pool);
 
 	btr_pcur_close(&pcur);
 	mtr_commit(&mtr);
 
-	if (leaf_in_buf_pool) {
-
-		if (found) {
-			/* Index entry exists and is in the buffer pool, no
-			need to use the insert/delete buffer. */
-
-			return(row_purge_remove_sec_if_poss_low_nonbuffered(
-				       node, index, entry, BTR_MODIFY_LEAF));
-		} else {
-			/* Index entry does not exist, nothing to do. */
+	switch (search_result) {
+	case ROW_NOT_FOUND:
+		/* Index entry does not exist, nothing to do. */
+		ut_ad(leaf_in_buf_pool);
+		return(TRUE);
 
-			return(TRUE);
-		}
+	case ROW_FOUND:
+		/* The index entry exists and is in the buffer pool;
+		no need to use the insert/delete buffer. */
+		ut_ad(leaf_in_buf_pool);
+		goto unbuffered;
+
+	case ROW_BUFFERED:
+		/* We did not pass any BTR_INSERT, BTR_DELETE, or
+		BTR_DELETE_MARK flag.  Therefore, the operation must
+		not have been buffered yet. */
+		ut_error;
+
+	case ROW_NOT_IN_POOL:
+		ut_ad(!leaf_in_buf_pool);
+		break;
 	}
 
-	/* We should remove the index record if no later version of the row,
-	which cannot be purged yet, requires its existence. If some
-	requires, we should do nothing. */
+	/* We should remove the index record if no later version of
+	the row, which cannot be purged yet, requires its existence.
+	If some requires, we should do nothing. */
 
 	mtr_start(&mtr);
 
-	success = row_purge_reposition_pcur(BTR_SEARCH_LEAF, node, &mtr);
-
-	if (success) {
+	if (row_purge_reposition_pcur(BTR_SEARCH_LEAF, node, &mtr)) {
 		old_has = row_vers_old_has_index_entry(
 			TRUE, btr_pcur_get_rec(&node->pcur),
 			&mtr, index, entry);
@@ -358,7 +369,7 @@ row_purge_remove_sec_if_poss_low(
 
 	btr_pcur_commit_specify_mtr(&node->pcur, &mtr);
 
-	if (success && old_has) {
+	if (old_has) {
 		/* Can't remove the index record yet. */
 
 		buf_pool_watch_clear();
@@ -370,26 +381,35 @@ row_purge_remove_sec_if_poss_low(
 
 	/* Set the query thread, so that ibuf_insert_low() will be
 	able to invoke thd_get_trx(). */
-	btr_cur->thr = que_node_get_parent(node);
+	btr_pcur_get_btr_cur(&pcur)->thr = que_node_get_parent(node);
 
-	row_search_index_entry(&was_buffered, index, entry,
-			       BTR_MODIFY_LEAF | BTR_DELETE, &pcur,
-			       &mtr);
+	search_result = row_search_index_entry(
+		index, entry, BTR_MODIFY_LEAF | BTR_DELETE, &pcur, &mtr);
 
 	btr_pcur_close(&pcur);
 	mtr_commit(&mtr);
 
 	buf_pool_watch_clear();
 
-	if (!was_buffered) {
-		/* Page read into buffer pool or delete-buffering failed. */
+	switch (search_result) {
+	case ROW_NOT_FOUND:
+	case ROW_FOUND:
+		break;
 
-		return(row_purge_remove_sec_if_poss_low_nonbuffered(
-			       node, index, entry, BTR_MODIFY_LEAF));
+	case ROW_BUFFERED:
+		return(TRUE);
+
+	case ROW_NOT_IN_POOL:
+		/* BTR_WATCH_LEAF was not specified,
+		so this should not occur! */
+		ut_error;
 	}
 
-	return(TRUE);
+	/* Page read into buffer pool or delete-buffering failed. */
 
+unbuffered:
+	return(row_purge_remove_sec_if_poss_low_nonbuffered(node, index,
+							    entry, mode));
 }
 
 /***************************************************************

row/row0row.c

@@ -781,13 +781,11 @@ row_get_clust_rec(
 /*******************************************************************
 Searches an index record. */
 UNIV_INTERN
-ibool
+enum row_search_result
 row_search_index_entry(
 /*===================*/
-				/* out: TRUE if found */
-	ibool*		was_buffered,
-				/* out: TRUE if the operation was buffered
-				in the insert/delete buffer. Can be NULL. */
+				/* out: whether the record was found
+				or buffered */
 	dict_index_t*	index,	/* in: index */
 	const dtuple_t*	entry,	/* in: index entry */
 	ulint		mode,	/* in: BTR_MODIFY_LEAF, ... */
@@ -798,30 +796,23 @@ row_search_index_entry(
 	ulint	n_fields;
 	ulint	low_match;
 	rec_t*	rec;
-	ibool	ret;
 
 	ut_ad(dtuple_check_typed(entry));
 
 	btr_pcur_open(index, entry, PAGE_CUR_LE, mode, pcur, mtr);
 
-	ret = btr_pcur_was_buffered(pcur);
+	if (btr_pcur_was_buffered(pcur)) {
 
-	if (was_buffered) {
-		*was_buffered = ret;
+		return(ROW_BUFFERED);
 	}
 
-	if (ret) {
-		/* Operation was buffered in the insert/delete buffer;
-		pretend that we found the record. */
-
-		return(TRUE);
-	} else if ((mode & BTR_WATCH_LEAF)
-		   && !btr_pcur_get_btr_cur(pcur)->leaf_in_buf_pool) {
+	if ((mode & BTR_WATCH_LEAF)
+	    && !btr_pcur_get_btr_cur(pcur)->leaf_in_buf_pool) {
 
 		/* We did not read in the leaf page, thus we can't have
 		found anything. */
 
-		return(FALSE);
+		return(ROW_NOT_IN_POOL);
 	}
 
 	low_match = btr_pcur_get_low_match(pcur);
@@ -832,14 +823,13 @@ row_search_index_entry(
 
 	if (page_rec_is_infimum(rec)) {
 
-		return(FALSE);
+		return(ROW_NOT_FOUND);
 	} else if (low_match != n_fields) {
-		/* Not found */
 
-		return(FALSE);
+		return(ROW_NOT_FOUND);
 	}
 
-	return(TRUE);
+	return(ROW_FOUND);
 }
 
 #ifndef UNIV_HOTBACKUP

row/row0uins.c

@@ -129,37 +129,40 @@ row_undo_ins_remove_sec_low(
 	dict_index_t*	index,	/* in: index */
 	dtuple_t*	entry)	/* in: index entry to remove */
 {
-	btr_pcur_t	pcur;
-	btr_cur_t*	btr_cur;
-	ibool		found;
-	ibool		success;
-	ulint		err;
-	mtr_t		mtr;
+	btr_pcur_t		pcur;
+	btr_cur_t*		btr_cur;
+	ulint			err;
+	mtr_t			mtr;
+	enum row_search_result	search_result;
 
 	log_free_check();
 	mtr_start(&mtr);
 
-	found = row_search_index_entry(NULL, index, entry, mode, &pcur, &mtr);
-
 	btr_cur = btr_pcur_get_btr_cur(&pcur);
 
-	if (!found) {
-		/* Not found */
-
-		btr_pcur_close(&pcur);
-		mtr_commit(&mtr);
-
-		return(DB_SUCCESS);
+	ut_ad(mode == BTR_MODIFY_TREE || mode == BTR_MODIFY_LEAF);
+
+	search_result = row_search_index_entry(index, entry, mode,
+					       &pcur, &mtr);
+
+	switch (search_result) {
+	case ROW_NOT_FOUND:
+		err = DB_SUCCESS;
+		goto func_exit;
+	case ROW_FOUND:
+		break;
+	case ROW_BUFFERED:
+	case ROW_NOT_IN_POOL:
+		/* These are invalid outcomes, because the mode passed
+		to row_search_index_entry() did not include any of the
+		flags BTR_INSERT, BTR_DELETE, BTR_DELETE_MARK, or
+		BTR_WATCH_LEAF. */
+		ut_error;
 	}
 
 	if (mode == BTR_MODIFY_LEAF) {
-		success = btr_cur_optimistic_delete(btr_cur, &mtr);
-
-		if (success) {
-			err = DB_SUCCESS;
-		} else {
-			err = DB_FAIL;
-		}
+		err = btr_cur_optimistic_delete(btr_cur, &mtr)
+			? DB_SUCCESS : DB_FAIL;
 	} else {
 		ut_ad(mode == BTR_MODIFY_TREE);
 
@@ -172,7 +175,7 @@ row_undo_ins_remove_sec_low(
 		btr_cur_pessimistic_delete(&err, FALSE, btr_cur,
 					   RB_NORMAL, &mtr);
 	}
-
+func_exit:
 	btr_pcur_close(&pcur);
 	mtr_commit(&mtr);
 

row/row0umod.c

@@ -295,29 +295,38 @@ row_undo_mod_del_mark_or_remove_sec_low(
 	ulint		mode)	/* in: latch mode BTR_MODIFY_LEAF or
 				BTR_MODIFY_TREE */
 {
-	ibool		found;
-	btr_pcur_t	pcur;
-	btr_cur_t*	btr_cur;
-	ibool		success;
-	ibool		old_has;
-	ulint		err;
-	mtr_t		mtr;
-	mtr_t		mtr_vers;
+	btr_pcur_t		pcur;
+	btr_cur_t*		btr_cur;
+	ibool			success;
+	ibool			old_has;
+	ulint			err;
+	mtr_t			mtr;
+	mtr_t			mtr_vers;
+	enum row_search_result	search_result;
 
 	log_free_check();
 	mtr_start(&mtr);
 
-	found = row_search_index_entry(NULL, index, entry, mode, &pcur, &mtr);
-
 	btr_cur = btr_pcur_get_btr_cur(&pcur);
 
-	if (!found) {
-		/* Not found */
-
-		btr_pcur_close(&pcur);
-		mtr_commit(&mtr);
-
-		return(DB_SUCCESS);
+	ut_ad(mode == BTR_MODIFY_TREE || mode == BTR_MODIFY_LEAF);
+
+	search_result = row_search_index_entry(index, entry, mode,
+					       &pcur, &mtr);
+
+	switch (search_result) {
+	case ROW_NOT_FOUND:
+		err = DB_SUCCESS;
+		goto func_exit;
+	case ROW_FOUND:
+		break;
+	case ROW_BUFFERED:
+	case ROW_NOT_IN_POOL:
+		/* These are invalid outcomes, because the mode passed
+		to row_search_index_entry() did not include any of the
+		flags BTR_INSERT, BTR_DELETE, BTR_DELETE_MARK, or
+		BTR_WATCH_LEAF. */
+		ut_error;
 	}
 
 	/* We should remove the index record if no prior version of the row,
@@ -366,6 +375,8 @@ row_undo_mod_del_mark_or_remove_sec_low(
 	}
 
 	btr_pcur_commit_specify_mtr(&(node->pcur), &mtr_vers);
+
+func_exit:
 	btr_pcur_close(&pcur);
 	mtr_commit(&mtr);
 
@@ -421,13 +432,15 @@ row_undo_mod_del_unmark_sec_and_undo_update(
 	dict_index_t*	index,	/* in: index */
 	dtuple_t*	entry)	/* in: index entry */
 {
-	mem_heap_t*	heap;
-	btr_pcur_t	pcur;
-	upd_t*		update;
-	ulint		err		= DB_SUCCESS;
-	big_rec_t*	dummy_big_rec;
-	mtr_t		mtr;
-	trx_t*		trx		= thr_get_trx(thr);
+	mem_heap_t*		heap;
+	btr_pcur_t		pcur;
+	btr_cur_t*		btr_cur;
+	upd_t*			update;
+	ulint			err		= DB_SUCCESS;
+	big_rec_t*		dummy_big_rec;
+	mtr_t			mtr;
+	trx_t*			trx		= thr_get_trx(thr);
+	enum row_search_result	search_result;
 
 	/* Ignore indexes that are being created. */
 	if (UNIV_UNLIKELY(*index->name == TEMP_INDEX_PREFIX)) {
@@ -438,8 +451,20 @@ row_undo_mod_del_unmark_sec_and_undo_update(
 	log_free_check();
 	mtr_start(&mtr);
 
-	if (UNIV_UNLIKELY(!row_search_index_entry(NULL, index, entry,
-						  mode, &pcur, &mtr))) {
+	ut_ad(mode == BTR_MODIFY_TREE || mode == BTR_MODIFY_LEAF);
+
+	search_result = row_search_index_entry(index, entry, mode,
+					       &pcur, &mtr);
+
+	switch (search_result) {
+	case ROW_BUFFERED:
+	case ROW_NOT_IN_POOL:
+		/* These are invalid outcomes, because the mode passed
+		to row_search_index_entry() did not include any of the
+		flags BTR_INSERT, BTR_DELETE, BTR_DELETE_MARK, or
+		BTR_WATCH_LEAF. */
+		ut_error;
+	case ROW_NOT_FOUND:
 		fputs("InnoDB: error in sec index entry del undo in\n"
 		      "InnoDB: ", stderr);
 		dict_index_name_print(stderr, trx, index);
@@ -454,9 +479,9 @@ row_undo_mod_del_unmark_sec_and_undo_update(
 		fputs("\n"
 		      "InnoDB: Submit a detailed bug report"
 		      " to http://bugs.mysql.com\n", stderr);
-	} else {
-		btr_cur_t*	btr_cur = btr_pcur_get_btr_cur(&pcur);
-
+		break;
+	case ROW_FOUND:
+		btr_cur = btr_pcur_get_btr_cur(&pcur);
 		err = btr_cur_del_mark_set_sec_rec(BTR_NO_LOCKING_FLAG,
 						   btr_cur, FALSE, thr, &mtr);
 		ut_a(err == DB_SUCCESS);

row/row0upd.c

@@ -1407,19 +1407,18 @@ row_upd_sec_index_entry(
 	upd_node_t*	node,	/* in: row update node */
 	que_thr_t*	thr)	/* in: query thread */
 {
-	mtr_t		mtr;
-	rec_t*		rec;
-	btr_pcur_t	pcur;
-	mem_heap_t*	heap;
-	dtuple_t*	entry;
-	dict_index_t*	index;
-	ibool		found;
-	btr_cur_t*	btr_cur;
-	ibool		referenced;
-	ibool		was_buffered;
-	ulint		err = DB_SUCCESS;
-	trx_t*		trx = thr_get_trx(thr);
-	ulint		mode = BTR_MODIFY_LEAF;
+	mtr_t			mtr;
+	const rec_t*		rec;
+	btr_pcur_t		pcur;
+	mem_heap_t*		heap;
+	dtuple_t*		entry;
+	dict_index_t*		index;
+	btr_cur_t*		btr_cur;
+	ibool			referenced;
+	ulint			err	= DB_SUCCESS;
+	trx_t*			trx	= thr_get_trx(thr);
+	ulint			mode	= BTR_MODIFY_LEAF;
+	enum row_search_result	search_result;
 
 	index = node->index;
 
@@ -1445,10 +1444,9 @@ row_upd_sec_index_entry(
 		mode |= BTR_DELETE_MARK;
 	}
 
-	found = row_search_index_entry(
-		&was_buffered, index, entry, mode, &pcur, &mtr);
-
-	if (was_buffered) {
+	search_result = row_search_index_entry(index, entry, mode,
+					       &pcur, &mtr);
+	if (search_result == ROW_BUFFERED) {
 		/* Entry was delete marked already. */
 
 		goto close_cur;
@@ -1458,7 +1456,12 @@ row_upd_sec_index_entry(
 
 	rec = btr_cur_get_rec(btr_cur);
 
-	if (UNIV_UNLIKELY(!found)) {
+	switch (search_result) {
+	case ROW_BUFFERED:	/* already handled above */
+	case ROW_NOT_IN_POOL:	/* should only occur for BTR_WATCH_LEAF */
+		ut_error;
+		break;
+	case ROW_NOT_FOUND:
 		fputs("InnoDB: error in sec index entry update in\n"
 		      "InnoDB: ", stderr);
 		dict_index_name_print(stderr, trx, index);
@@ -1475,7 +1478,8 @@ row_upd_sec_index_entry(
 		fputs("\n"
 		      "InnoDB: Submit a detailed bug report"
 		      " to http://bugs.mysql.com\n", stderr);
-	} else {
+		break;
+	case ROW_FOUND:
 		/* Delete mark the old index record; it can already be
 		delete marked if we return after a lock wait in
 		row_ins_index_entry below */
@@ -1501,6 +1505,7 @@ row_upd_sec_index_entry(
 					index, offsets, thr, &mtr);
 			}
 		}
+		break;
 	}
 
 close_cur: