set Display.errch and use it for errors from mouse/keyboard

draw/alloc.go

@@ -86,23 +86,18 @@ func allocImage(d *Display, ai *Image, r image.Rectangle, pix Pix, repl bool, va
 	return i, nil
 }
 
-/*
-func namedimage(d *Display, name string) (*Image, nil) {
-	panic("namedimage")
-}
-
+/* implements message 'N' */
 func nameimage(i *Image, name string, in bool) error {
-	a := i.Display.bufimage(1+4+1+1+len(name))
+	a := i.Display.bufimage(1 + 4 + 1 + 1 + len(name))
 	a[0] = 'N'
-	bplong(a[1:], i.ID)
+	bplong(a[1:], i.id)
 	if in {
 		a[5] = 1
 	}
-	a[6] = len(name)
+	a[6] = byte(len(name))
 	copy(a[7:], name)
-	return d.flushimage(false)
+	return i.Display.flush(false)
 }
-*/
 
 func (i *Image) free() error {
 	if i == nil || i.Display == nil {

draw/draw.go

@@ -1,5 +1,8 @@
 // Package draw is a port of Plan 9's libdraw to Go.
-// It connects to the 'devdraw' binary built as part of Plan 9 from User Space (http://swtch.com/plan9port/).
+//
+// On Plan 9 it talks to /dev/draw and rio(4) at $wsys directly.
+// On unix, it connects to the 'devdraw' binary built as part of Plan 9 from User Space (http://swtch.com/plan9port/).
+//
 // All graphics operations are done in the remote server. The functions
 // in this package typically send a message to the server.
 //

draw/getsubfont.go

@@ -1,38 +1,10 @@
 package draw
 
 import (
-	"bytes"
-	"fmt"
 	"image"
-	"io/ioutil"
 	"log"
-	"os"
-	"strings"
 )
 
-func getsubfont(d *Display, name string) (*Subfont, error) {
-	scale, fname := parsefontscale(name)
-	data, err := ioutil.ReadFile(fname)
-	if err != nil && strings.HasPrefix(fname, "/mnt/font/") {
-		data1, err1 := fontPipe(fname[len("/mnt/font/"):])
-		if err1 == nil {
-			data, err = data1, err1
-		}
-	}
-	if err != nil {
-		fmt.Fprintf(os.Stderr, "getsubfont: %v\n", err)
-		return nil, err
-	}
-	f, err := d.readSubfont(name, bytes.NewReader(data), nil)
-	if err != nil {
-		fmt.Fprintf(os.Stderr, "getsubfont: can't read %s: %v\n", fname, err)
-	}
-	if scale > 1 {
-		scalesubfont(f, scale)
-	}
-	return f, err
-}
-
 func scalesubfont(f *Subfont, scale int) {
 	r := f.Bits.R
 	r2 := r

draw/getsubfont_devdraw.go

@@ -0,0 +1,34 @@
+// +build !plan9
+
+package draw
+
+import (
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"strings"
+)
+
+func getsubfont(d *Display, name string) (*Subfont, error) {
+	scale, fname := parsefontscale(name)
+	data, err := ioutil.ReadFile(fname)
+	if err != nil && strings.HasPrefix(fname, "/mnt/font/") {
+		data1, err1 := fontPipe(fname[len("/mnt/font/"):])
+		if err1 == nil {
+			data, err = data1, err1
+		}
+	}
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "getsubfont: %v\n", err)
+		return nil, err
+	}
+	f, err := d.readSubfont(name, bytes.NewReader(data), nil)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "getsubfont: can't read %s: %v\n", fname, err)
+	}
+	if scale > 1 {
+		scalesubfont(f, scale)
+	}
+	return f, err
+}

draw/getsubfont_plan9.go

@@ -0,0 +1,27 @@
+// +build plan9
+
+package draw
+
+import (
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"os"
+)
+
+func getsubfont(d *Display, name string) (*Subfont, error) {
+	scale, fname := parsefontscale(name)
+	data, err := ioutil.ReadFile(fname)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "getsubfont: %v\n", err)
+		return nil, err
+	}
+	f, err := d.readSubfont(name, bytes.NewReader(data), nil)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "getsubfont: can't read %s: %v\n", fname, err)
+	}
+	if scale > 1 {
+		scalesubfont(f, scale)
+	}
+	return f, err
+}

draw/init.go → draw/init_devdraw.go

@@ -1,3 +1,5 @@
+// +build !plan9
+
 package draw
 
 import (
@@ -88,6 +90,9 @@ func Init(errch chan<- error, fontname, label, winsize string) (*Display, error)
 	if err != nil {
 		return nil, err
 	}
+	if errch == nil {
+		errch = make(chan error)
+	}
 	d := &Display{
 		conn:    c,
 		errch:   errch,
@@ -361,7 +366,7 @@ func bpshort(b []byte, n uint16) {
 }
 
 func (d *Display) HiDPI() bool {
-	return d.DPI >= DefaultDPI*3/2 
+	return d.DPI >= DefaultDPI*3/2
 }
 
 func (d *Display) ScaleSize(n int) int {