feat: initial version of midifi software

This CL introduces the initial version of the midifi software, via
a simplified CLI interface "playsmf".

Though it is far from complete, this version can be manually invoked
with the locations of the MIDI communications port (the `-com` flag),
and MIDI file. It will playback the MIDI file with the correct time.

Software is currently tested with an integration test, that invokes the
program with a known MIDI file and compares the output of the serial
port, standard out, and standard error. Golden files can be updated by
providing the `-test.update-golden` flag.

Change-Id: I312bc721736e2edf385ece5141133ffa6bd20a72
Signed-off-by: Terin Stock <terinjokes@gmail.com>

1 files changed, 73 insertions, 0 deletions

diff --git a/pkg/ttymididrv/driver.go b/pkg/ttymididrv/driver.go
new file mode 100644
index 0000000..cc7b1fd
--- /dev/null
+++ b/pkg/ttymididrv/driver.go
@@ -0,0 +1,73 @@
+package ttymididrv
+
+import (
+	"sync"
+
+	"gitlab.com/gomidi/midi/mid"
+)
+
+type driver struct {
+	mu     sync.RWMutex
+	outs   []mid.Out
+	opened []mid.Port
+	closed bool
+}
+
+func New(name string, baud int) mid.Driver {
+	d := &driver{}
+	d.outs = []mid.Out{
+		&out{
+			name:   name,
+			baud:   baud,
+			number: 0,
+			driver: d,
+		},
+	}
+
+	return d
+}
+
+func (d *driver) String() string {
+	return "ttymididrv"
+}
+
+func (d *driver) Close() (err error) {
+	d.mu.RLock()
+	if d.closed {
+		d.mu.RUnlock()
+		return mid.ErrClosed
+	}
+	d.mu.RUnlock()
+
+	d.mu.Lock()
+	d.closed = true
+	d.mu.Unlock()
+
+	for _, p := range d.opened {
+		err = p.Close()
+	}
+
+	return
+}
+
+func (d *driver) Ins() ([]mid.In, error) {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+
+	if d.closed {
+		return nil, mid.ErrClosed
+	}
+
+	return nil, nil
+}
+
+func (d *driver) Outs() ([]mid.Out, error) {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+
+	if d.closed {
+		return nil, mid.ErrClosed
+	}
+
+	return d.outs, nil
+}