MDEV-12501 -- set --maturity-level by default

  * Note: breaking change; since this commit, a plugin that has
    worked so far might get rejected due to plugin maturity
  * mariabackup is not affected (allows all plugins)
  * VERSION file defines SERVER_MATURITY, which defines the
    corresponding numeric value as SERVER_MATURITY_LEVEL in
    include/mysql_version.h
  * The default value for 'plugin_maturity' is SERVER_MATURITY_LEVEL - 1
  * Logs a warning if a plugin has maturity lower than
    SERVER_MATURITY_LEVEL
  * Tests suppress the plugin maturity warning
  * Tests use --plugin-maturity=unknown by default so as not to fail
    due to the stricter plugin maturity handling

1 files changed, 9 insertions, 0 deletions

diff --git a/sql/sql_plugin.cc b/sql/sql_plugin.cc
index 9478db8e6d5..462829a255b 100644
--- a/sql/sql_plugin.cc
+++ b/sql/sql_plugin.cc
@@ -1155,6 +1155,7 @@ static bool plugin_add(MEM_ROOT *tmp_root,
       report_error(report, ER_CANT_OPEN_LIBRARY, dl->str, ENOEXEC, buf);
       goto err;
     }
+
     if (plugin_maturity_map[plugin->maturity] < plugin_maturity)
     {
       char buf[256];
@@ -1167,6 +1168,14 @@ static bool plugin_add(MEM_ROOT *tmp_root,
       report_error(report, ER_CANT_OPEN_LIBRARY, dl->str, EPERM, buf);
       goto err;
     }
+    else if (plugin_maturity_map[plugin->maturity] < SERVER_MATURITY_LEVEL)
+    {
+      sql_print_warning("Plugin '%s' is of maturity level %s while the server is %s",
+        tmp.name.str,
+        plugin_maturity_names[plugin->maturity],
+        plugin_maturity_names[SERVER_MATURITY_LEVEL]);
+    }
+
     tmp.plugin= plugin;
     tmp.ref_count= 0;
     tmp.state= PLUGIN_IS_UNINITIALIZED;