Fix bug where a few input lines are skipped

1 files changed, 22 insertions, 0 deletions

diff --git a/internal/line/line.go b/internal/line/line.go
new file mode 100644
index 0000000..02dbbcc
--- /dev/null
+++ b/internal/line/line.go
@@ -0,0 +1,22 @@
+package line
+
+import "sync"
+
+type Line struct {
+	sync.Mutex
+	num int64
+}
+
+func (l *Line) Inc() {
+	l.Lock()
+	defer l.Unlock()
+
+	l.num++
+}
+
+func (l *Line) Num() int64 {
+	l.Lock()
+	defer l.Unlock()
+
+	return l.num
+}