MDEV-26832: ROW_NUMBER in SIGNAL/RESIGNAL causes a syntax error

Analysis: Parser was missing ROW_NUMBER as syntax for SIGNAL and RESIGNAL.
Fix: Fix parser and fix how m_row_number is copied like other attributes
to avoid ROW_NUMBER from assuming default value.

mysql-test/main/get_diagnostics.result

@@ -1689,3 +1689,42 @@ SELECT @n, @m;
 @n	@m
 2	Out of range value for column 'f' at row 2
 DROP TABLE t;
+#
+# MDEV-26832: ROW_NUMBER in SIGNAL/RESIGNAL causes a syntax error
+#
+# using signal
+CREATE PROCEDURE signal_syntax()
+BEGIN
+DECLARE errno INT DEFAULT 0;
+DECLARE msg TEXT DEFAULT "foo";
+DECLARE row_num INT DEFAULT 0;
+DECLARE cond CONDITION FOR SQLSTATE "01234";
+DECLARE CONTINUE HANDLER for 1012
+BEGIN
+GET DIAGNOSTICS CONDITION 1 errno = MYSQL_ERRNO, msg = MESSAGE_TEXT, row_num= ROW_NUMBER;
+END;
+SIGNAL cond SET MESSAGE_TEXT = "Signal message", MYSQL_ERRNO = 1012, ROW_NUMBER= 5;
+SELECT errno, msg, row_num;
+END|
+CALL signal_syntax();
+errno	msg	row_num
+1012	Signal message	5
+DROP PROCEDURE signal_syntax;
+# using resignal
+CREATE PROCEDURE resignal_syntax()
+BEGIN
+DECLARE CONTINUE HANDLER
+FOR 1146
+BEGIN
+RESIGNAL SET
+MESSAGE_TEXT = '`temptab` does not exist', ROW_NUMBER= 105;
+END;
+SELECT `c` FROM `temptab`;
+END|
+CALL resignal_syntax();
+ERROR 42S02: `temptab` does not exist
+GET DIAGNOSTICS CONDITION 1 @row_num= ROW_NUMBER;
+SELECT @row_num;
+@row_num
+105
+DROP PROCEDURE resignal_syntax;

mysql-test/main/get_diagnostics.test

@@ -1565,3 +1565,56 @@ GET DIAGNOSTICS CONDITION 2 @n= ROW_NUMBER, @m = MESSAGE_TEXT;
 SELECT @n, @m;
 
 DROP TABLE t;
+
+--echo #
+--echo # MDEV-26832: ROW_NUMBER in SIGNAL/RESIGNAL causes a syntax error
+--echo #
+
+--echo # using signal
+
+DELIMITER |;
+CREATE PROCEDURE signal_syntax()
+BEGIN
+  DECLARE errno INT DEFAULT 0;
+  DECLARE msg TEXT DEFAULT "foo";
+  DECLARE row_num INT DEFAULT 0;
+  DECLARE cond CONDITION FOR SQLSTATE "01234";
+  DECLARE CONTINUE HANDLER for 1012
+  BEGIN
+    GET DIAGNOSTICS CONDITION 1 errno = MYSQL_ERRNO, msg = MESSAGE_TEXT, row_num= ROW_NUMBER;
+  END;
+
+  SIGNAL cond SET MESSAGE_TEXT = "Signal message", MYSQL_ERRNO = 1012, ROW_NUMBER= 5;
+
+  SELECT errno, msg, row_num;
+END|
+DELIMITER ;|
+
+CALL signal_syntax();
+
+DROP PROCEDURE signal_syntax;
+
+--echo # using resignal
+
+DELIMITER |;
+
+CREATE PROCEDURE resignal_syntax()
+BEGIN
+   DECLARE CONTINUE HANDLER
+   FOR 1146
+   BEGIN
+      RESIGNAL SET
+      MESSAGE_TEXT = '`temptab` does not exist', ROW_NUMBER= 105;
+   END;
+   SELECT `c` FROM `temptab`;
+END|
+
+DELIMITER ;|
+
+--error ER_NO_SUCH_TABLE
+CALL resignal_syntax();
+
+GET DIAGNOSTICS CONDITION 1 @row_num= ROW_NUMBER;
+SELECT @row_num;
+
+DROP PROCEDURE resignal_syntax;

sql/sql_class.h

@@ -560,7 +560,8 @@ typedef enum enum_diag_condition_item_name
   DIAG_CURSOR_NAME= 9,
   DIAG_MESSAGE_TEXT= 10,
   DIAG_MYSQL_ERRNO= 11,
-  LAST_DIAG_SET_PROPERTY= DIAG_MYSQL_ERRNO
+  DIAG_ROW_NUMBER= 12,
+  LAST_DIAG_SET_PROPERTY= DIAG_ROW_NUMBER
 } Diag_condition_item_name;
 
 /**

sql/sql_error.cc

@@ -204,6 +204,7 @@ Sql_condition::copy_opt_attributes(const Sql_condition *cond)
   copy_string(m_mem_root, & m_table_name, & cond->m_table_name);
   copy_string(m_mem_root, & m_column_name, & cond->m_column_name);
   copy_string(m_mem_root, & m_cursor_name, & cond->m_cursor_name);
+  m_row_number= cond->m_row_number;
 }
 
 

sql/sql_signal.cc

@@ -44,6 +44,7 @@ const LEX_CSTRING Diag_condition_item_names[]=
   { STRING_WITH_LEN("CURSOR_NAME") },
   { STRING_WITH_LEN("MESSAGE_TEXT") },
   { STRING_WITH_LEN("MYSQL_ERRNO") },
+  { STRING_WITH_LEN("ROW_NUMBER") },
 
   { STRING_WITH_LEN("CONDITION_IDENTIFIER") },
   { STRING_WITH_LEN("CONDITION_NUMBER") },
@@ -309,6 +310,26 @@ int Sql_cmd_common_signal::eval_signal_informations(THD *thd, Sql_condition *con
     cond->m_sql_errno= (int) code;
   }
 
+  set= m_set_signal_information.m_item[DIAG_ROW_NUMBER];
+  if (set != NULL)
+  {
+    if (set->is_null())
+    {
+      thd->raise_error_printf(ER_WRONG_VALUE_FOR_VAR,
+                              "ROW_NUMBER", "NULL");
+      goto end;
+    }
+    longlong row_number_value= set->val_int();
+    if (row_number_value < 0)
+    {
+      str= set->val_str(& str_value);
+      thd->raise_error_printf(ER_WRONG_VALUE_FOR_VAR,
+                              "ROW_NUMBER", str->c_ptr_safe());
+      goto end;
+    }
+    cond->m_row_number= (ulong) row_number_value;
+  }
+
   /*
     The various item->val_xxx() methods don't return an error code,
     but flag thd in case of failure.

sql/sql_yacc.yy

@@ -3475,6 +3475,8 @@ signal_condition_information_item_name:
           { $$= DIAG_MESSAGE_TEXT; }
         | MYSQL_ERRNO_SYM
           { $$= DIAG_MYSQL_ERRNO; }
+        | ROW_NUMBER_SYM
+          { $$= DIAG_ROW_NUMBER; }
         ;
 
 resignal_stmt: