decoder: return const decoder_plugin structs

The decoder_plugin structs must never change.  Don't work with
non-const pointers.

1 files changed, 2 insertions, 1 deletions

diff --git a/src/ls.h b/src/ls.h
index da79bbbd2..ed0f0677f 100644
--- a/src/ls.h
+++ b/src/ls.h
@@ -32,7 +32,8 @@ int isValidRemoteUtf8Url(const char *utf8url);
 
 int isRemoteUrl(const char *url);
 
-struct decoder_plugin *hasMusicSuffix(const char *utf8file, unsigned int next);
+const struct decoder_plugin *
+hasMusicSuffix(const char *utf8file, unsigned int next);
 
 int printRemoteUrlHandlers(struct client *client);