boot v2 progress: disks, ssh, success...

shio/shio.go

@@ -0,0 +1,118 @@
+// Shared IO
+package shio
+
+import (
+	"io"
+	"sync"
+
+	"novit.nc/direktil/initrd/colorio"
+)
+
+type ShIO struct {
+	buf       []byte
+	closed    bool
+	cond      *sync.Cond
+	hideInput bool
+}
+
+func New() *ShIO {
+	return NewWithCap(1024)
+}
+func NewWithCap(capacity int) *ShIO {
+	return NewWithBytes(make([]byte, 0, capacity))
+}
+func NewWithBytes(content []byte) *ShIO {
+	return &ShIO{
+		buf:  content,
+		cond: sync.NewCond(&sync.Mutex{}),
+	}
+}
+
+var (
+	_ io.WriteCloser = New()
+)
+
+func (s *ShIO) Write(data []byte) (n int, err error) {
+	s.cond.L.Lock()
+	defer s.cond.L.Unlock()
+
+	if s.closed {
+		err = io.EOF
+		return
+	}
+
+	if s.hideInput {
+		s.buf = append(s.buf, colorio.Reset...)
+	}
+
+	s.buf = append(s.buf, data...)
+	n = len(data)
+
+	if s.hideInput {
+		s.buf = append(s.buf, colorio.Hidden...)
+	}
+
+	s.cond.Broadcast()
+	return
+}
+
+func (s *ShIO) HideInput() {
+	s.cond.L.Lock()
+	defer s.cond.L.Unlock()
+
+	if s.closed {
+		return
+	}
+
+	s.buf = append(s.buf, colorio.Hidden...)
+	s.hideInput = true
+}
+func (s *ShIO) ShowInput() {
+	s.cond.L.Lock()
+	defer s.cond.L.Unlock()
+
+	if s.closed {
+		return
+	}
+
+	s.buf = append(s.buf, colorio.Reset...)
+	s.hideInput = false
+}
+
+func (s *ShIO) Close() (err error) {
+	s.cond.L.Lock()
+	defer s.cond.L.Unlock()
+
+	s.closed = true
+
+	s.cond.Broadcast()
+	return
+}
+
+func (s *ShIO) NewReader() io.Reader {
+	return &shioReader{s, 0}
+}
+
+type shioReader struct {
+	in  *ShIO
+	pos int
+}
+
+func (r *shioReader) Read(ba []byte) (n int, err error) {
+	r.in.cond.L.Lock()
+	defer r.in.cond.L.Unlock()
+
+	for r.pos == len(r.in.buf) && !r.in.closed {
+		r.in.cond.Wait()
+	}
+
+	if r.pos == len(r.in.buf) && r.in.closed {
+		err = io.EOF
+		return
+	}
+
+	n = copy(ba, r.in.buf[r.pos:])
+	r.pos += n
+
+	return
+}

shio/shio_test.go

@@ -0,0 +1,52 @@
+package shio
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"sync"
+	"time"
+)
+
+func ExampleOutput() {
+	done := false
+	defer func() { done = true }()
+	go func() {
+		time.Sleep(time.Second)
+		if !done {
+			panic("timeout")
+		}
+	}()
+
+	shio := NewWithCap(3)
+
+	r1 := shio.NewReader()
+
+	// read as you write
+	wg := new(sync.WaitGroup)
+	wg.Add(1)
+	go func() {
+		defer wg.Done()
+		io.Copy(os.Stdout, r1)
+		fmt.Println("-- r1 done --")
+	}()
+
+	fmt.Fprintln(shio, "hello1")
+	fmt.Fprintln(shio, "hello2")
+	shio.Close()
+
+	wg.Wait()
+
+	// read after close
+	r2 := shio.NewReader()
+	io.Copy(os.Stdout, r2)
+	fmt.Println("-- r2 done --")
+
+	// Output:
+	// hello1
+	// hello2
+	// -- r1 done --
+	// hello1
+	// hello2
+	// -- r2 done --
+}