refs #5431, put some defensive checks in for mysql 5.6 alter table in tokudb storage engine

git-svn-id: file:///svn/mysql/tokudb-engine/tokudb-engine@47650 c7de825b-a66e-492c-adef-691d508d4ae1

storage/tokudb/ha_tokudb_alter_56.cc

@@ -299,13 +299,19 @@ ha_tokudb::check_if_supported_inplace_alter(TABLE *altered_table, Alter_inplace_
         HA_CREATE_INFO *create_info = ha_alter_info->create_info;
         // alter auto_increment
         if (only_flags(create_info->used_fields, HA_CREATE_USED_AUTO)) {
+            // do a sanity check that the table is what we think it is
+            if (tables_have_same_keys_and_columns(table, altered_table, true)) {
                 result = HA_ALTER_INPLACE_EXCLUSIVE_LOCK;
             }
+        }
 #ifndef MARIADB_BASE_VERSION
         // alter row_format
         else if (only_flags(create_info->used_fields, HA_CREATE_USED_ROW_FORMAT)) {
+            // do a sanity check that the table is what we think it is
+            if (tables_have_same_keys_and_columns(table, altered_table, true)) {
                 result = HA_ALTER_INPLACE_EXCLUSIVE_LOCK;
             }
+        }
 #endif
     }
 

storage/tokudb/ha_tokudb_alter_common.cc

@@ -677,3 +677,50 @@ find_changed_columns(
 cleanup:
     return retval;
 }
+
+static bool
+tables_have_same_keys_and_columns(TABLE* first_table, TABLE* second_table, bool print_error) {
+    bool retval;
+    if (first_table->s->null_bytes != second_table->s->null_bytes) {
+        retval = false;
+        if (print_error) {
+            sql_print_error(
+                "tables have different number of null bytes, %d, %d", 
+                first_table->s->null_bytes, 
+                second_table->s->null_bytes
+                );
+        }
+        goto exit;
+    }
+    if (first_table->s->fields != second_table->s->fields) {
+        retval = false;
+        if (print_error) {
+            sql_print_error(
+                "tables have different number of fields, %d, %d", 
+                first_table->s->fields, 
+                second_table->s->fields
+                );
+        }
+        goto exit;
+    }
+    for (uint i = 0; i < first_table->s->fields; i++) {
+        Field* a = first_table->field[i];
+        Field* b = second_table->field[i];
+        if (!are_two_fields_same(a,b)) {
+            retval = false;
+            sql_print_error(
+                "tables have different fields at position %d", 
+                i
+                );
+            goto exit;
+        }
+    }
+    if (!tables_have_same_keys(first_table, second_table, print_error, true)) {
+        retval = false;
+        goto exit;
+    }
+
+    retval = true;
+exit:
+    return retval;
+}