1 files changed, 16 insertions, 11 deletions

diff --git a/src/midifile.rs b/src/midifile.rs
index 71a861c..219a931 100644
--- a/src/midifile.rs
+++ b/src/midifile.rs
@@ -10,6 +10,7 @@ pub struct RawMidiEvent
     data: Vec<u8>
 }
 
+#[derive(Clone)]
 pub enum MidiEvent
 {
     NoteOn{ch: u8, key: u8, vel: u8},
@@ -26,6 +27,7 @@ pub enum MidiEvent
     MetaEndOfTrack
 }
 
+#[derive(Clone)]
 pub struct TimedMidiEvent
 {
     pub t: u32,
@@ -39,7 +41,7 @@ impl From<&MidiEvent> for RawMidiEvent
         match e
         {
             MidiEvent::NoteOff{ch, key, vel}
-                              if *vel == 0x40 => RawMidiEvent{ty: 0x90 | ch, p1: *key, p2: 0, data:vec![]},
+                              if *vel == 0x40 => RawMidiEvent{ty: 0x90 | ch, p1: *key, p2: 0, data: vec![]},
             MidiEvent::NoteOff{ch, key, vel} => RawMidiEvent{ty: 0x80 | ch, p1: *key, p2: *vel, data: vec![]},
             MidiEvent::NoteOn {ch, key, vel} => RawMidiEvent{ty: 0x90 | ch, p1: *key, p2: *vel, data: vec![]},
             MidiEvent::KeyAfterTouch{ch, key, val} => RawMidiEvent{ty: 0xa0 | ch, p1: *key, p2: *val, data: vec![]},
@@ -64,12 +66,12 @@ impl From<&MidiEvent> for RawMidiEvent
                     RawMidiEvent{ty: 0xff, p1: 0x03, p2: s.len() as u8, data: Vec::from(sb)}
                 }
             MidiEvent::MetaEndOfTrack =>
-                RawMidiEvent{ty: 0xff, p1: 0x2f, p2: 0xff, data: vec![]}
+                RawMidiEvent{ty: 0xff, p1: 0x2f, p2: 0, data: vec![]}
         }
     }
 }
 
-type MidiTrack = Vec<TimedMidiEvent>;
+pub type MidiTrack = Vec<TimedMidiEvent>;
 
 pub struct MidiFile
 {
@@ -77,19 +79,19 @@ pub struct MidiFile
     pub tracks: Vec<MidiTrack>
 }
 
-fn write_u16be(f: &mut File, v: u16) -> io::Result<()>
+fn write_u16be<W>(f: &mut W, v: u16) -> io::Result<()> where W: Write
 {
     let bytes = v.to_be_bytes();
     f.write_all(&bytes)
 }
 
-fn write_u32be(f: &mut File, v: u32) -> io::Result<()>
+fn write_u32be<W>(f: &mut W, v: u32) -> io::Result<()> where W: Write
 {
     let bytes = v.to_be_bytes();
     f.write_all(&bytes)
 }
 
-fn write_varlen(f: &mut File, v: u32) -> io::Result<()>
+fn write_varlen<W>(f: &mut W, v: u32) -> io::Result<()> where W: Write
 {
     if v > 0x0fffffff
     { return Err(io::Error::new(io::ErrorKind::InvalidData, "Invalid variable length value")); }
@@ -103,7 +105,7 @@ fn write_varlen(f: &mut File, v: u32) -> io::Result<()>
     f.write_all(&buf[..])
 }
 
-fn write_raw_event(f: &mut File, re: &RawMidiEvent) -> io::Result<()>
+fn write_raw_event<W>(f: &mut W, re: &RawMidiEvent) -> io::Result<()> where W: Write
 {
     let mut buf: Vec<u8> = Vec::new();
     buf.push(re.ty);
@@ -113,23 +115,26 @@ fn write_raw_event(f: &mut File, re: &RawMidiEvent) -> io::Result<()>
     f.write_all(&buf[..])
 }
 
-fn write_track(f: &mut File, trk: &MidiTrack) -> io::Result<()>
+fn write_track<W>(f: &mut W, trk: &MidiTrack) -> io::Result<()> where W: Write
 {
     let header = "MTrk".as_bytes();
     f.write_all(header)?;
+    let mut buf: Vec<u8> = Vec::new();
     let mut curt = 0u32;
     for te in trk
     {
         let TimedMidiEvent{t, e} = te;
-        write_varlen(f, t - curt)?;
+        write_varlen(&mut buf, t - curt)?;
         curt = *t;
         let re = RawMidiEvent::from(e);
-        write_raw_event(f, &re)?;
+        write_raw_event(&mut buf, &re)?;
     }
+    write_u32be(f, buf.len() as u32)?;
+    f.write_all(&buf[..])?;
     Ok(())
 }
 
-fn write_file(filename: &str, mf: &MidiFile) -> io::Result<()>
+pub fn write_file(filename: &str, mf: &MidiFile) -> io::Result<()>
 {
     let mut f = File::create(filename)?;
     let header = "MThd".as_bytes();