decoder/opus: move SeekFindEOS() to OggFind.cxx

src/decoder/OggFind.cxx

@@ -20,6 +20,8 @@
 #include "config.h"
 #include "OggFind.hxx"
 #include "OggSyncState.hxx"
+#include "InputStream.hxx"
+#include "util/Error.hxx"
 
 bool
 OggFindEOS(OggSyncState &oy, ogg_stream_state &os, ogg_packet &packet)
@@ -35,3 +37,20 @@ OggFindEOS(OggSyncState &oy, ogg_stream_state &os, ogg_packet &packet)
 			return true;
 	}
 }
+
+bool
+OggSeekFindEOS(OggSyncState &oy, ogg_stream_state &os, ogg_packet &packet,
+	       InputStream &is)
+{
+	if (is.size > 0 && is.size - is.offset < 65536)
+		return OggFindEOS(oy, os, packet);
+
+	if (!is.CheapSeeking())
+		return false;
+
+	oy.Reset();
+
+	return is.LockSeek(-65536, SEEK_END, IgnoreError()) &&
+		oy.ExpectPageSeekIn(os) &&
+		OggFindEOS(oy, os, packet);
+}

src/decoder/OggFind.hxx

@@ -24,6 +24,7 @@
 
 #include <ogg/ogg.h>
 
+struct InputStream;
 class OggSyncState;
 
 /**
@@ -35,4 +36,14 @@ class OggSyncState;
 bool
 OggFindEOS(OggSyncState &oy, ogg_stream_state &os, ogg_packet &packet);
 
+/**
+ * Try to find the end-of-stream (EOS) packet.  Seek to the end of the
+ * file if necessary.
+ *
+ * @return true if the EOS packet was found
+ */
+bool
+OggSeekFindEOS(OggSyncState &oy, ogg_stream_state &os, ogg_packet &packet,
+	       InputStream &is);
+
 #endif

src/decoder/OpusDecoderPlugin.cxx

@@ -292,24 +292,6 @@ mpd_opus_stream_decode(Decoder &decoder,
 }
 
 static bool
-SeekFindEOS(OggSyncState &oy, ogg_stream_state &os, ogg_packet &packet,
-	    InputStream &is)
-{
-	if (is.size > 0 && is.size - is.offset < 65536)
-		return OggFindEOS(oy, os, packet);
-
-	if (!is.CheapSeeking())
-		return false;
-
-	oy.Reset();
-
-	Error error;
-	return is.LockSeek(-65536, SEEK_END, error) &&
-		oy.ExpectPageSeekIn(os) &&
-		OggFindEOS(oy, os, packet);
-}
-
-static bool
 mpd_opus_scan_stream(InputStream &is,
 		     const struct tag_handler *handler, void *handler_ctx)
 {
@@ -367,7 +349,7 @@ mpd_opus_scan_stream(InputStream &is,
 		}
 	}
 
-	if (packet.e_o_s || SeekFindEOS(oy, os, packet, is))
+	if (packet.e_o_s || OggSeekFindEOS(oy, os, packet, is))
 		tag_handler_invoke_duration(handler, handler_ctx,
 					    packet.granulepos / opus_sample_rate);