From ca06c6fb9d1fbe02082946adec7a1389cd0f7f7d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Fr=C3=A9d=C3=A9ric=20Mangano-Tarumi?= <fmang@mg0.fr>
Date: Sat, 8 Dec 2018 12:55:58 -0500
Subject: [PATCH] detect muxed streams

---
 src/cli.cc   |  8 ++++++++
 t/opustags.t | 14 +++++++++++++-
 2 files changed, 21 insertions(+), 1 deletion(-)
 mode change 100644 => 100755 t/opustags.t

diff --git a/src/cli.cc b/src/cli.cc
index b19604e..b4ec54a 100644
--- a/src/cli.cc
+++ b/src/cli.cc
@@ -184,6 +184,8 @@ static ot::status edit_tags(ot::opus_tags& tags, const ot::options& opt)
  */
 static ot::status process(ot::ogg_reader& reader, ot::ogg_writer* writer, const ot::options &opt)
 {
+	bool focused = false; /*< the stream on which we operate is defined */
+	int focused_serialno; /*< when focused, the serialno of the focused stream */
 	/** \todo Become stream-aware instead of counting the pages of all streams together. */
 	int absolute_page_no = -1; /*< page number in the physical stream, not logical */
 	for (;;) {
@@ -197,6 +199,12 @@ static ot::status process(ot::ogg_reader& reader, ot::ogg_writer* writer, const
 		++absolute_page_no;
 		auto serialno = ogg_page_serialno(&reader.page);
 		auto pageno = ogg_page_pageno(&reader.page);
+		if (!focused) {
+			focused = true;
+			focused_serialno = serialno;
+		} else if (serialno != focused_serialno) {
+			return {ot::st::error, "Muxed streams are not supported yet."};
+		}
 		if (absolute_page_no == 0) { // Identification header
 			if (!ot::is_opus_stream(reader.page))
 				return {ot::st::error, "Not an Opus stream."};
diff --git a/t/opustags.t b/t/opustags.t
old mode 100644
new mode 100755
index bf9f6a2..7a3205e
--- a/t/opustags.t
+++ b/t/opustags.t
@@ -4,7 +4,7 @@ use strict;
 use warnings;
 use utf8;
 
-use Test::More tests => 28;
+use Test::More tests => 29;
 
 use Digest::MD5;
 use File::Basename;
@@ -190,3 +190,15 @@ my $data = slurp 'out.opus';
 is_deeply(opustags('-', '-o', '-', {in => $data, mode => ':raw'}), [$data, '', 0], 'read opus from stdin and write to stdout');
 
 unlink('out.opus');
+
+####################################################################################################
+# Test muxed streams
+
+system('ffmpeg -loglevel error -y -i gobble.opus -c copy -map 0:0 -map 0:0 -shortest muxed.ogg') == 0
+	or BAIL_OUT('could not create a muxed stream');
+
+is_deeply(opustags('muxed.ogg'), ['', <<'END_ERR', 256], 'muxed streams detection');
+error: Muxed streams are not supported yet.
+END_ERR
+
+unlink('muxed.ogg');