SMF add support for type-0 files (count channels, not tracks)

2 files changed, 49 insertions, 1 deletions

diff --git a/libs/evoral/evoral/SMF.hpp b/libs/evoral/evoral/SMF.hpp
index fd7263b5c4..0cbd5bb638 100644
--- a/libs/evoral/evoral/SMF.hpp
+++ b/libs/evoral/evoral/SMF.hpp
@@ -21,6 +21,7 @@
 #define EVORAL_SMF_HPP
 
 #include <glibmm/threads.h>
+#include <set>
 
 #include "evoral/visibility.h"
 #include "evoral/types.hpp"
@@ -49,7 +50,7 @@ public:
 		std::string _file_name;
 	};
 
-	SMF() : _smf(0), _smf_track(0), _empty(true) {};
+	SMF();
 	virtual ~SMF();
 
 	static bool test(const std::string& path);
@@ -75,11 +76,17 @@ public:
 
 	double round_to_file_precision (double val) const;
 
+	bool is_type0 () const { return _type0; }
+	std::set<uint8_t> channels () const { return _type0channels; }
+
 private:
 	smf_t*       _smf;
 	smf_track_t* _smf_track;
 	bool         _empty; ///< true iff file contains(non-empty) events
 	mutable Glib::Threads::Mutex _smf_lock;
+
+	bool              _type0;
+	std::set<uint8_t> _type0channels;
 };
 
 }; /* namespace Evoral */
diff --git a/libs/evoral/src/SMF.cpp b/libs/evoral/src/SMF.cpp
index 65304c4e4d..f5dc4fa1e0 100644
--- a/libs/evoral/src/SMF.cpp
+++ b/libs/evoral/src/SMF.cpp
@@ -39,6 +39,13 @@ using namespace std;
 
 namespace Evoral {
 
+SMF::SMF()
+	: _smf (0)
+	, _smf_track (0)
+	, _empty (true)
+	, _type0 (false)
+	{};
+
 SMF::~SMF()
 {
 	close ();
@@ -107,6 +114,9 @@ SMF::open(const std::string& path, int track) THROW_FILE_ERROR
 {
 	Glib::Threads::Mutex::Lock lm (_smf_lock);
 
+	_type0 = false;
+	_type0channels.clear ();
+
 	assert(track >= 1);
 	if (_smf) {
 		smf_delete(_smf);
@@ -133,6 +143,33 @@ SMF::open(const std::string& path, int track) THROW_FILE_ERROR
 	}
 
 	fclose(f);
+
+	lm.release ();
+	if (_smf->format == 0 && _smf->number_of_tracks == 1 && !_empty) {
+		// type-0 file: scan file for # of used channels.
+		int ret;
+		uint32_t delta_t = 0;
+		uint32_t size    = 0;
+		uint8_t* buf     = NULL;
+		event_id_t event_id = 0;
+		seek_to_start();
+		while ((ret = read_event (&delta_t, &size, &buf, &event_id)) >= 0) {
+			if (ret == 0) {
+				continue;
+			}
+			if (size == 0) {
+				break;
+			}
+			uint8_t type = buf[0] & 0xf0;
+			uint8_t chan = buf[0] & 0x0f;
+			if (type < 0x80 || type > 0xE0) {
+				continue;
+			}
+			_type0channels.insert(chan);
+		}
+		_type0 = true;
+		seek_to_start();
+	}
 	return 0;
 }
 
@@ -193,6 +230,8 @@ SMF::create(const std::string& path, int track, uint16_t ppqn) THROW_FILE_ERROR
 	}
 
 	_empty = true;
+	_type0 = false;
+	_type0channels.clear ();
 
 	return 0;
 }
@@ -206,6 +245,8 @@ SMF::close() THROW_FILE_ERROR
 		smf_delete(_smf);
 		_smf = 0;
 		_smf_track = 0;
+		_type0 = false;
+		_type0channels.clear ();
 	}
 }