[tarantool-patches] Re: [PATCH v2 0/7] sql: store regular identifiers in case-normal form

[Kirill Shcherbatov <kshcherbatov@tarantool.org>]

>> +idlist(A) ::= nm(Y). {
>> +  /* A-overwrites-Y. */
>> +  A = sql_id_list_append(pParse->db,0,&Y);
>> +  if (A == NULL)
>> +    sql_parser_error(pParse);
> 
> 1. Why do not you return after an error?
Same as in previous patches. I don't mind return here.

>> +/**
>> + * Append a new element to the given IdList. Create a new IdList
>> + * if need be.
>> + *
>> + * @param db The database connection.
>> + * @param list The pointer to existent Id list if exists.
>> + * @param name_token The token containing name.
>> + * @retval Not NULL IdList pointer is returned on success.
>> + * @retval NULL otherwise. Diag message is set.
>> + */
>> +struct IdList *
>> +sql_id_list_append(struct sql *db, struct IdList *pList, struct Token *pToken);
> 
> 2. The arg names are old, and do not match the implementation
> and the comment.
Fixed.

====================================================

Refactored sqlSrcListAppend routine as sql_src_list_append and
reworked it to use diag_set in case of memory allocation error.
This change is necessary because the sql_src_list_append body has
a sqlNameFromToken call that will be changed in subsequent
patches.

This patch refers to a series of preparatory patches that provide
the use of Tarantool errors in the call tree that includes
sqlNormalizeName, since this call can later return errors.

This patch is not self-sufficient, its sqlNameFromToken call
remained to be non-Tarantool (for now). It means, that if
sqlNameFromToken fails in sql_src_list_append there is no
diag message created.

Part of #3931
---
 src/box/sql/build.c         | 70 +++++++++----------------------------
 src/box/sql/delete.c        | 16 +++++----
 src/box/sql/fk_constraint.c | 19 +++++-----
 src/box/sql/parse.y         | 24 ++++++++++---
 src/box/sql/select.c        |  8 ++---
 src/box/sql/sqlInt.h        | 20 ++++++++++-
 src/box/sql/trigger.c       | 11 +++---
 7 files changed, 85 insertions(+), 83 deletions(-)

diff --git a/src/box/sql/build.c b/src/box/sql/build.c
index 9f065e7b4..ef38503da 100644
--- a/src/box/sql/build.c
+++ b/src/box/sql/build.c
@@ -2630,64 +2630,26 @@ sql_src_list_new(struct sql *db)
 	return src_list;
 }
 
-/*
- * Append a new table name to the given SrcList.  Create a new SrcList if
- * need be.  A new entry is created in the SrcList even if pTable is NULL.
- *
- * A SrcList is returned, or NULL if there is an OOM error.  The returned
- * SrcList might be the same as the SrcList that was input or it might be
- * a new one.  If an OOM error does occurs, then the prior value of pList
- * that is input to this routine is automatically freed.
- *
- * If pDatabase is not null, it means that the table has an optional
- * database name prefix.  Like this:  "database.table".  The pDatabase
- * points to the table name and the pTable points to the database name.
- * The SrcList.a[].zName field is filled with the table name which might
- * come from pTable (if pDatabase is NULL) or from pDatabase.
- * SrcList.a[].zDatabase is filled with the database name from pTable,
- * or with NULL if no database is specified.
- *
- * In other words, if call like this:
- *
- *         sqlSrcListAppend(D,A,B,0);
- *
- * Then B is a table name and the database name is unspecified.  If called
- * like this:
- *
- *         sqlSrcListAppend(D,A,B,C);
- *
- * Then C is the table name and B is the database name.  If C is defined
- * then so is B.  In other words, we never have a case where:
- *
- *         sqlSrcListAppend(D,A,0,C);
- *
- * Both pTable and pDatabase are assumed to be quoted.  They are dequoted
- * before being added to the SrcList.
- */
-SrcList *
-sqlSrcListAppend(sql * db,	/* Connection to notify of malloc failures */
-		     SrcList * pList,	/* Append to this SrcList. NULL creates a new SrcList */
-		     Token * pTable	/* Table to append */
-    )
+struct SrcList *
+sql_src_list_append(struct sql *db, struct SrcList *list,
+		    struct Token *name_token)
 {
-	struct SrcList_item *pItem;
-	assert(db != 0);
-	if (pList == 0) {
-		pList = sql_src_list_new(db);
-		if (pList == 0)
-			return 0;
+	if (list == NULL) {
+		list = sql_src_list_new(db);
+		if (list == NULL)
+			return NULL;
 	} else {
 		struct SrcList *new_list =
-			sql_src_list_enlarge(db, pList, 1, pList->nSrc);
+			sql_src_list_enlarge(db, list, 1, list->nSrc);
 		if (new_list == NULL) {
-			sqlSrcListDelete(db, pList);
+			sqlSrcListDelete(db, list);
 			return NULL;
 		}
-		pList = new_list;
+		list = new_list;
 	}
-	pItem = &pList->a[pList->nSrc - 1];
-	pItem->zName = sqlNameFromToken(db, pTable);
-	return pList;
+	struct SrcList_item *item = &list->a[list->nSrc - 1];
+	item->zName = sqlNameFromToken(db, name_token);
+	return list;
 }
 
 /*
@@ -2779,10 +2741,12 @@ sqlSrcListAppendFromTerm(Parse * pParse,	/* Parsing context */
 		pParse->is_aborted = true;
 		goto append_from_error;
 	}
-	p = sqlSrcListAppend(db, p, pTable);
-	if (p == 0 || NEVER(p->nSrc == 0)) {
+	p = sql_src_list_append(db, p, pTable);
+	if (p == NULL) {
+		pParse->is_aborted = true;
 		goto append_from_error;
 	}
+	assert(p->nSrc != 0);
 	pItem = &p->a[p->nSrc - 1];
 	assert(pAlias != 0);
 	if (pAlias->n) {
diff --git a/src/box/sql/delete.c b/src/box/sql/delete.c
index f4d0334f4..4bc63346c 100644
--- a/src/box/sql/delete.c
+++ b/src/box/sql/delete.c
@@ -70,14 +70,16 @@ sql_materialize_view(struct Parse *parse, const char *name, struct Expr *where,
 		     int cursor)
 {
 	struct sql *db = parse->db;
-	where = sqlExprDup(db, where, 0);
-	struct SrcList *from = sqlSrcListAppend(db, NULL, NULL);
-	if (from != NULL) {
-		assert(from->nSrc == 1);
-		from->a[0].zName = sqlDbStrDup(db, name);
-		assert(from->a[0].pOn == NULL);
-		assert(from->a[0].pUsing == NULL);
+	struct SrcList *from = sql_src_list_append(db, NULL, NULL);
+	if (from == NULL) {
+		parse->is_aborted = true;
+		return;
 	}
+	where = sqlExprDup(db, where, 0);
+	assert(from->nSrc == 1);
+	from->a[0].zName = sqlDbStrDup(db, name);
+	assert(from->a[0].pOn == NULL);
+	assert(from->a[0].pUsing == NULL);
 	struct Select *select = sqlSelectNew(parse, NULL, from, where, NULL,
 						 NULL, NULL, 0, NULL, NULL);
 	struct SelectDest dest;
diff --git a/src/box/sql/fk_constraint.c b/src/box/sql/fk_constraint.c
index 4066b1cf1..cc4dc6448 100644
--- a/src/box/sql/fk_constraint.c
+++ b/src/box/sql/fk_constraint.c
@@ -618,9 +618,11 @@ fk_constraint_emit_check(struct Parse *parser, struct space *space, int reg_old,
 		 * table. We need the child table as a SrcList for
 		 * sqlWhereBegin().
 		 */
-		struct SrcList *src = sqlSrcListAppend(db, NULL, NULL);
-		if (src == NULL)
-			continue;
+		struct SrcList *src = sql_src_list_append(db, NULL, NULL);
+		if (src == NULL) {
+			parser->is_aborted = true;
+			return;
+		}
 		struct SrcList_item *item = src->a;
 		struct space *child = space_by_id(fk->def->child_id);
 		assert(child != NULL);
@@ -866,11 +868,12 @@ fk_constraint_action_trigger(struct Parse *pParse, struct space_def *def,
 					     "constraint failed");
 		if (r != NULL)
 			r->on_conflict_action = ON_CONFLICT_ACTION_ABORT;
-		select = sqlSelectNew(pParse,
-					  sql_expr_list_append(db, NULL, r),
-					  sqlSrcListAppend(db, NULL, &err),
-					  where, NULL, NULL, NULL, 0, NULL,
-					  NULL);
+		struct SrcList *src_list = sql_src_list_append(db, NULL, &err);
+		if (src_list == NULL)
+			pParse->is_aborted = true;
+		select = sqlSelectNew(pParse, sql_expr_list_append(db, NULL, r),
+				      src_list, where, NULL, NULL, NULL, 0,
+				      NULL, NULL);
 		where = NULL;
 	}
 
diff --git a/src/box/sql/parse.y b/src/box/sql/parse.y
index b27651c3b..ead71dfc0 100644
--- a/src/box/sql/parse.y
+++ b/src/box/sql/parse.y
@@ -616,8 +616,14 @@ seltablist(A) ::= stl_prefix(A) LP seltablist(F) RP
 
 %type fullname {SrcList*}
 %destructor fullname {sqlSrcListDelete(pParse->db, $$);}
-fullname(A) ::= nm(X).  
-   {A = sqlSrcListAppend(pParse->db,0,&X); /*A-overwrites-X*/}
+fullname(A) ::= nm(X). {
+  /*A-overwrites-X. */
+  A = sql_src_list_append(pParse->db,0,&X);
+  if (A == NULL) {
+    pParse->is_aborted = true;
+    return;
+  }
+}
 
 %type joinop {int}
 join_nm(A) ::= id(A).
@@ -1160,7 +1166,11 @@ expr(A) ::= expr(A) in_op(N) LP select(Y) RP(E).  [IN] {
   A.zEnd = &E.z[E.n];
 }
 expr(A) ::= expr(A) in_op(N) nm(Y) paren_exprlist(E). [IN] {
-  SrcList *pSrc = sqlSrcListAppend(pParse->db, 0,&Y);
+  struct SrcList *pSrc = sql_src_list_append(pParse->db, 0,&Y);
+  if (pSrc == NULL) {
+    pParse->is_aborted = true;
+    return;
+  }
   Select *pSelect = sqlSelectNew(pParse, 0,pSrc,0,0,0,0,0,0,0);
   if( E )  sqlSrcListFuncArgs(pParse, pSelect ? pSrc : 0, E);
   A.pExpr = sqlPExpr(pParse, TK_IN, A.pExpr, 0);
@@ -1230,8 +1240,12 @@ paren_exprlist(A) ::= LP exprlist(X) RP.  {A = X;}
 //
 cmd ::= createkw(S) uniqueflag(U) INDEX ifnotexists(NE) nm(X)
         ON nm(Y) LP sortlist(Z) RP. {
-  sql_create_index(pParse, &X, sqlSrcListAppend(pParse->db,0,&Y), Z, &S,
-                   SORT_ORDER_ASC, NE, U);
+  struct SrcList *src_list = sql_src_list_append(pParse->db,0,&Y);
+  if (src_list == NULL) {
+    pParse->is_aborted = true;
+    return;
+  }
+  sql_create_index(pParse, &X, src_list, Z, &S, SORT_ORDER_ASC, NE, U);
 }
 
 %type uniqueflag {int}
diff --git a/src/box/sql/select.c b/src/box/sql/select.c
index 9ebd65bad..1b7d52b68 100644
--- a/src/box/sql/select.c
+++ b/src/box/sql/select.c
@@ -256,7 +256,7 @@ findRightmost(Select * p)
 
 
 /**
- * Work the same as sqlSrcListAppend(), but before adding to
+ * Work the same as sql_src_list_append(), but before adding to
  * list provide check on name duplicates: only values with unique
  * names are appended. Moreover, names of tables are not
  * normalized: it is parser's business and in struct Select they
@@ -4118,9 +4118,9 @@ flattenSubquery(Parse * pParse,		/* Parsing context */
 		} else {
 			assert(pParent != p);	/* 2nd and subsequent times through the loop */
 			pSrc = pParent->pSrc =
-			    sqlSrcListAppend(db, 0, 0);
-			if (pSrc == 0) {
-				assert(db->mallocFailed);
+			    sql_src_list_append(db, 0, 0);
+			if (pSrc == NULL) {
+				pParse->is_aborted = true;
 				break;
 			}
 		}
diff --git a/src/box/sql/sqlInt.h b/src/box/sql/sqlInt.h
index 2b31f8b19..b6c89893a 100644
--- a/src/box/sql/sqlInt.h
+++ b/src/box/sql/sqlInt.h
@@ -3451,7 +3451,25 @@ sql_src_list_enlarge(struct sql *db, struct SrcList *src_list, int new_slots,
 struct SrcList *
 sql_src_list_new(struct sql *db);
 
-SrcList *sqlSrcListAppend(sql *, SrcList *, Token *);
+/**
+ * Append a new table name to the given list. Create a new
+ * SrcList if need be. A new entry is created in the list even
+ * if name_token is NULL.
+ *
+ * @param db The database connection.
+ * @param list Append to this SrcList. NULL creates a new SrcList.
+ * @param name_token Token representing table name.
+ * @retval Not NULL SrcList pointer is returned. The returned
+ *         SrcList might be the same as the list that was input
+ *         or it might be a new one.
+ * @retval NULL Otherwise. The diag message is set. The prior
+ *         value of list that is input to this routine is
+ *         automatically freed.
+ */
+struct SrcList *
+sql_src_list_append(struct sql *db, struct SrcList *list,
+		    struct Token *name_token);
+
 SrcList *sqlSrcListAppendFromTerm(Parse *, SrcList *, Token *,
 				      Token *, Select *, Expr *, IdList *);
 void sqlSrcListIndexedBy(Parse *, SrcList *, Token *);
diff --git a/src/box/sql/trigger.c b/src/box/sql/trigger.c
index 7eacd33d4..b1f5033c4 100644
--- a/src/box/sql/trigger.c
+++ b/src/box/sql/trigger.c
@@ -587,12 +587,13 @@ targetSrcList(Parse * pParse,	/* The parsing context */
 	sql *db = pParse->db;
 	SrcList *pSrc;		/* SrcList to be returned */
 
-	pSrc = sqlSrcListAppend(db, 0, 0);
-	if (pSrc) {
-		assert(pSrc->nSrc > 0);
-		pSrc->a[pSrc->nSrc - 1].zName =
-		    sqlDbStrDup(db, pStep->zTarget);
+	pSrc = sql_src_list_append(db, 0, 0);
+	if (pSrc == NULL) {
+		pParse->is_aborted = true;
+		return NULL;
 	}
+	assert(pSrc->nSrc > 0);
+	pSrc->a[pSrc->nSrc - 1].zName = sqlDbStrDup(db, pStep->zTarget);
 	return pSrc;
 }
 
-- 
2.21.0