diff --git a/src/input/CurlInputPlugin.cxx b/src/input/CurlInputPlugin.cxx
index 29d8266ce..cc9987a19 100644
--- a/src/input/CurlInputPlugin.cxx
+++ b/src/input/CurlInputPlugin.cxx
@@ -24,11 +24,7 @@
 #include "tag.h"
 #include "IcyMetaDataParser.hxx"
 #include "event/MultiSocketMonitor.hxx"
-
-extern "C" {
 #include "input_internal.h"
-}
-
 #include "event/Loop.hxx"
 #include "IOThread.hxx"
 #include "glib_compat.h"
diff --git a/src/input/SoupInputPlugin.cxx b/src/input/SoupInputPlugin.cxx
index 5a60fa725..fb446136c 100644
--- a/src/input/SoupInputPlugin.cxx
+++ b/src/input/SoupInputPlugin.cxx
@@ -20,11 +20,7 @@
 #include "config.h"
 #include "SoupInputPlugin.hxx"
 #include "input_plugin.h"
-
-extern "C" {
 #include "input_internal.h"
-}
-
 #include "IOThread.hxx"
 #include "event/Loop.hxx"
 #include "conf.h"
diff --git a/src/input_internal.h b/src/input_internal.h
index d95142e46..688afaa6e 100644
--- a/src/input_internal.h
+++ b/src/input_internal.h
@@ -27,6 +27,10 @@
 struct input_stream;
 struct input_plugin;
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 void
 input_stream_init(struct input_stream *is, const struct input_plugin *plugin,
 		  const char *uri, GMutex *mutex, GCond *cond);
@@ -40,4 +44,8 @@ input_stream_signal_client(struct input_stream *is);
 void
 input_stream_set_ready(struct input_stream *is);
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif