Merging #5409 from 1.2.x branch

CHANGELOG

@@ -136,6 +136,7 @@ Cacti CHANGELOG
 -issue#5390: Fix SQL error when saving DS template
 -issue#5392: Template import should not end with php error
 -issue#5403: Cacti Log regular expression filters can not calculate 'does not match' properly
+-issue#5409: Enabling a plugin can have no response
 -issue#5413: Rows Per Page - Not all options are available
 -issue#5414: Plugins are unable to modify fields in the setting 'Change Device Settings'
 -issue#5417: Cacti mailer log message misses 'bcc' addresses in log notification

lib/plugins.php

@@ -737,6 +737,12 @@ function api_plugin_install($plugin) {
 
 		$author  = $info['author'];
 		$version = $info['version'];
+	} elseif (strpos($plugin, 'plugin_') !== false) {
+		raise_message('directory_error', __('The Plugin directory \'%s\' needs to be renamed to remove \'plugin_\' from the name before it can be installed.', $plugin), MESSAGE_LEVEL_ERROR);
+		return false;
+	} else {
+		raise_message('version_error', __('The Plugin in the directory \'%s\' does not include an version function \'%s()\'.  This function must exist for the plugin to be installed.', $plugin, $function), MESSAGE_LEVEL_ERROR);
+		return false;
 	}
 
 	db_execute_prepared('INSERT INTO plugin_config
@@ -763,6 +769,9 @@ function api_plugin_install($plugin) {
 				WHERE directory = ?',
 				array($plugin));
 		}
+	} else {
+		raise_message('install_error', __('The Plugin in the directory \'%s\' does not include an install function \'%s()\'.  This function must exist for the plugin to be installed.', $plugin, $function), MESSAGE_LEVEL_ERROR);
+		return false;
 	}
 
 	api_plugin_replicate_config();