Check if parameter is NULL in plugins which only works as viewer.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@22083 a1c6a512-1295-4272-9138-f99709370657

apps/plugins/iriverify.c

@@ -135,6 +135,7 @@ enum plugin_status plugin_start(const void* parameter)
     char *buf;
     int rc;
     int i;
+    if(!parameter) return PLUGIN_ERROR;
     filename = (char *)parameter;
 
     buf = rb->plugin_get_audio_buffer((size_t *)&buf_size); /* start munching memory */

apps/plugins/properties.c

@@ -275,6 +275,7 @@ enum plugin_status plugin_start(const void* parameter)
     int button;
     bool quit = false;
     char file[MAX_PATH];
+    if(!parameter) return PLUGIN_ERROR;
     rb->strcpy(file, (const char *) parameter);
 
     /* determine if it's a file or a directory */

apps/plugins/search.c

@@ -149,6 +149,7 @@ enum plugin_status plugin_start(const void* parameter)
     int ok;
     const char *filename = parameter;
     char *p;
+    if(!parameter) return PLUGIN_ERROR;
 
     DEBUGF("%s - %s\n", (char *)parameter, &filename[rb->strlen(filename)-4]);
     /* Check the extension. We only allow .m3u files. */

apps/plugins/sort.c

@@ -180,6 +180,7 @@ enum plugin_status plugin_start(const void* parameter)
 {
     char *buf;
     int rc;
+    if(!parameter) return PLUGIN_ERROR;
 
     filename = (char *)parameter;