[Tarantool-patches] [PATCH v4 2/5] sql: move diag setting to sql_func_by_signature()

[imeevma@tarantool.org]

After this patch, the sql_func_by_signature() function will check the
found function and set diag if something is wrong.

Needed for #4159
---
 src/box/sql/expr.c    |  2 --
 src/box/sql/func.c    | 18 +++++++++++++++---
 src/box/sql/resolve.c | 23 ++---------------------
 src/box/sql/sqlInt.h  |  7 +++++--
 4 files changed, 22 insertions(+), 28 deletions(-)

diff --git a/src/box/sql/expr.c b/src/box/sql/expr.c
index bc2182446..d0620b98c 100644
--- a/src/box/sql/expr.c
+++ b/src/box/sql/expr.c
@@ -3978,8 +3978,6 @@ sqlExprCodeTarget(Parse * pParse, Expr * pExpr, int target)
 			zId = pExpr->u.zToken;
 			struct func *func = sql_func_by_signature(zId, nFarg);
 			if (func == NULL) {
-				diag_set(ClientError, ER_NO_SUCH_FUNCTION,
-					 zId);
 				pParse->is_aborted = true;
 				break;
 			}
diff --git a/src/box/sql/func.c b/src/box/sql/func.c
index 487cdafe1..4bbe4d4b7 100644
--- a/src/box/sql/func.c
+++ b/src/box/sql/func.c
@@ -2185,11 +2185,23 @@ struct func *
 sql_func_by_signature(const char *name, int argc)
 {
 	struct func *base = func_by_name(name, strlen(name));
-	if (base == NULL || !base->def->exports.sql)
+	if (base == NULL) {
+		diag_set(ClientError, ER_NO_SUCH_FUNCTION, name);
 		return NULL;
-
-	if (base->def->param_count != -1 && base->def->param_count != argc)
+	}
+	if (!base->def->exports.sql) {
+		diag_set(ClientError, ER_SQL_PARSER_GENERIC,
+			 tt_sprintf("function %s() is not available in SQL",
+				     name));
+		return NULL;
+	}
+	int param_count = base->def->param_count;
+	if (param_count != -1 && param_count != argc) {
+		const char *err = tt_sprintf("%d", param_count);
+		diag_set(ClientError, ER_FUNC_WRONG_ARG_COUNT,
+			 base->def->name, err, argc);
 		return NULL;
+	}
 	return base;
 }
 
diff --git a/src/box/sql/resolve.c b/src/box/sql/resolve.c
index 6f625dc18..10c77c491 100644
--- a/src/box/sql/resolve.c
+++ b/src/box/sql/resolve.c
@@ -598,32 +598,13 @@ resolveExprStep(Walker * pWalker, Expr * pExpr)
 			assert(!ExprHasProperty(pExpr, EP_xIsSelect));
 			zId = pExpr->u.zToken;
 			nId = sqlStrlen30(zId);
-			struct func *func = func_by_name(zId, nId);
+			struct func *func = sql_func_by_signature(zId, n);
 			if (func == NULL) {
-				diag_set(ClientError, ER_NO_SUCH_FUNCTION, zId);
-				pParse->is_aborted = true;
-				pNC->nErr++;
-				return WRC_Abort;
-			}
-			if (!func->def->exports.sql) {
-				diag_set(ClientError, ER_SQL_PARSER_GENERIC,
-					 tt_sprintf("function %.*s() is not "
-						    "available in SQL",
-						     nId, zId));
-				pParse->is_aborted = true;
-				pNC->nErr++;
-				return WRC_Abort;
-			}
-			if (func->def->param_count != -1 &&
-			    func->def->param_count != n) {
-				uint32_t argc = func->def->param_count;
-				const char *err = tt_sprintf("%d", argc);
-				diag_set(ClientError, ER_FUNC_WRONG_ARG_COUNT,
-					 func->def->name, err, n);
 				pParse->is_aborted = true;
 				pNC->nErr++;
 				return WRC_Abort;
 			}
+			assert(func->def->exports.sql);
 			bool is_agg = func->def->aggregate ==
 				      FUNC_AGGREGATE_GROUP;
 			assert(!is_agg || func->def->language ==
diff --git a/src/box/sql/sqlInt.h b/src/box/sql/sqlInt.h
index 37283e506..58a65acc1 100644
--- a/src/box/sql/sqlInt.h
+++ b/src/box/sql/sqlInt.h
@@ -4441,8 +4441,11 @@ sql_func_flag_is_set(struct func *func, uint16_t flag)
  * export field set true and have exactly the same signature
  * are returned.
  *
- * Returns not NULL function pointer when a valid and exported
- * to SQL engine function is found and NULL otherwise.
+ * @param name Name of the function to find.
+ * @param argc Number of arguments of the function.
+ *
+ * @retval not NULL function pointer when a function is found.
+ * @retval NULL on error and sets a diag.
  */
 struct func *
 sql_func_by_signature(const char *name, int argc);
-- 
2.25.1