decoder/OggFind: move to lib/xiph/

src/lib/xiph/OggFind.cxx

@@ -0,0 +1,70 @@
+/*
+ * Copyright 2003-2016 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "config.h"
+#include "OggFind.hxx"
+#include "lib/xiph/OggSyncState.hxx"
+#include "input/InputStream.hxx"
+#include "util/Error.hxx"
+
+bool
+OggFindEOS(OggSyncState &oy, ogg_stream_state &os, ogg_packet &packet)
+{
+	while (true) {
+		int r = ogg_stream_packetout(&os, &packet);
+		if (r == 0) {
+			if (!oy.ExpectPageIn(os))
+				return false;
+
+			continue;
+		} else if (r > 0 && packet.e_o_s)
+			return true;
+	}
+}
+
+bool
+OggSeekPageAtOffset(OggSyncState &oy, ogg_stream_state &os, InputStream &is,
+		    offset_type offset)
+{
+	oy.Reset();
+
+	/* reset the stream to clear any previous partial packet
+	   data */
+	ogg_stream_reset(&os);
+
+	return is.LockSeek(offset, IgnoreError()) &&
+		oy.ExpectPageSeekIn(os);
+}
+
+bool
+OggSeekFindEOS(OggSyncState &oy, ogg_stream_state &os, ogg_packet &packet,
+	       InputStream &is)
+{
+	if (!is.KnownSize())
+		return false;
+
+	if (is.GetRest() < 65536)
+		return OggFindEOS(oy, os, packet);
+
+	if (!is.CheapSeeking())
+		return false;
+
+	return OggSeekPageAtOffset(oy, os, is, is.GetSize() - 65536) &&
+		OggFindEOS(oy, os, packet);
+}

src/lib/xiph/OggFind.hxx

@@ -0,0 +1,57 @@
+/*
+ * Copyright 2003-2016 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef MPD_OGG_FIND_HXX
+#define MPD_OGG_FIND_HXX
+
+#include "check.h"
+#include "input/Offset.hxx"
+
+#include <ogg/ogg.h>
+
+class OggSyncState;
+class InputStream;
+
+/**
+ * Skip all pages/packets until an end-of-stream (EOS) packet for the
+ * specified stream is found.
+ *
+ * @return true if the EOS packet was found
+ */
+bool
+OggFindEOS(OggSyncState &oy, ogg_stream_state &os, ogg_packet &packet);
+
+/**
+ * Seek the #InputStream and find the next Ogg page.
+ */
+bool
+OggSeekPageAtOffset(OggSyncState &oy, ogg_stream_state &os, InputStream &is,
+		    offset_type offset);
+
+/**
+ * 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