Multi clipboard format support for Windows

clipboard.go

@@ -10,11 +10,28 @@ func ReadAll() (string, error) {
 	return readAll()
 }
 
+func ReadAllWithFormat(cf uintptr) (string, error) {
+	return readAllWithFormat(cf)
+}
+
 // WriteAll write string to clipboard
 func WriteAll(text string) error {
 	return writeAll(text)
 }
 
+// WriteAllWithFormat write string to clipboard with format
+func WriteAllWithFormat(text string, cf uintptr) error {
+	return writeAllWithFormat(text, cf)
+}
+
+func ClearClipboard() error {
+	return clearClipboard()
+}
+
+func GetClipboardFormat(format string) (uintptr, error) {
+	return getClipboardFormat(format)
+}
+
 // Unsupported might be set true during clipboard init, to help callers decide
 // whether or not to offer clipboard options.
 var Unsupported bool

clipboard_darwin.go

@@ -32,6 +32,10 @@ func readAll() (string, error) {
 	return string(out), nil
 }
 
+func readAllWithFormat(_ uintptr) (string, error) {
+	return readAll()
+}
+
 func writeAll(text string) error {
 	copyCmd := getCopyCommand()
 	in, err := copyCmd.StdinPipe()
@@ -50,3 +54,15 @@ func writeAll(text string) error {
 	}
 	return copyCmd.Wait()
 }
+
+func writeAllWithFormat(text string, _ uintptr) error {
+	return writeAll(text)
+}
+
+func clearClipboard() error {
+	return nil
+}
+
+func getClipboardFormat(_ string) (uintptr, error) {
+	return 0, nil
+}

clipboard_test.go

@@ -2,16 +2,14 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package clipboard_test
+package clipboard
 
 import (
 	"testing"
-
-	. "github.com/atotto/clipboard"
 )
 
 func TestCopyAndPaste(t *testing.T) {
-	expected := "日本語"
+	expected := "日本語\n"
 
 	err := WriteAll(expected)
 	if err != nil {

clipboard_unix.go

@@ -75,6 +75,10 @@ func readAll() (string, error) {
 	return string(out), nil
 }
 
+func readAllWithFormat(_ uintptr) (string, error) {
+	return readAll()
+}
+
 func writeAll(text string) error {
 	if Unsupported {
 		return missingCommands
@@ -96,3 +100,15 @@ func writeAll(text string) error {
 	}
 	return copyCmd.Wait()
 }
+
+func writeAllWithFormat(text string, _ uintptr) error {
+	return writeAll(text)
+}
+
+func clearClipboard() error {
+	return nil
+}
+
+func getClipboardFormat(_ string) (uintptr, error) {
+	return 0, nil
+}

clipboard_windows.go

@@ -14,23 +14,26 @@ import (
 
 const (
 	cfUnicodetext = 13
+	cfText        = 1
 	gmemMoveable  = 0x0002
 )
 
 var (
-	user32           = syscall.MustLoadDLL("user32")
-	openClipboard    = user32.MustFindProc("OpenClipboard")
-	closeClipboard   = user32.MustFindProc("CloseClipboard")
-	emptyClipboard   = user32.MustFindProc("EmptyClipboard")
-	getClipboardData = user32.MustFindProc("GetClipboardData")
-	setClipboardData = user32.MustFindProc("SetClipboardData")
+	user32                  = syscall.MustLoadDLL("user32")
+	openClipboard           = user32.MustFindProc("OpenClipboard")
+	closeClipboard          = user32.MustFindProc("CloseClipboard")
+	emptyClipboard          = user32.MustFindProc("EmptyClipboard")
+	getClipboardData        = user32.MustFindProc("GetClipboardData")
+	setClipboardData        = user32.MustFindProc("SetClipboardData")
+	registerClipboardFormat = user32.MustFindProc("RegisterClipboardFormatW")
 
 	kernel32     = syscall.NewLazyDLL("kernel32")
 	globalAlloc  = kernel32.NewProc("GlobalAlloc")
 	globalFree   = kernel32.NewProc("GlobalFree")
+	globalSize   = kernel32.NewProc("GlobalSize")
 	globalLock   = kernel32.NewProc("GlobalLock")
 	globalUnlock = kernel32.NewProc("GlobalUnlock")
-	lstrcpy      = kernel32.NewProc("lstrcpyW")
+	memcpy       = kernel32.NewProc("RtlCopyMemory")
 )
 
 // waitOpenClipboard opens the clipboard, waiting for up to a second to do so.
@@ -50,14 +53,27 @@ func waitOpenClipboard() error {
 }
 
 func readAll() (string, error) {
+	return readAllWithFormat(cfText)
+}
+
+func readAllWithFormat(cf uintptr) (string, error) {
 	err := waitOpenClipboard()
 	if err != nil {
 		return "", err
 	}
 	defer closeClipboard.Call()
 
-	h, _, err := getClipboardData.Call(cfUnicodetext)
+	h, _, err := getClipboardData.Call(cf)
 	if h == 0 {
+		if err != syscall.Errno(0) {
+			return "", err
+		}
+
+		return "", nil
+	}
+
+	size, _, err := globalSize.Call(h)
+	if size == 0 {
 		return "", err
 	}
 
@@ -66,7 +82,7 @@ func readAll() (string, error) {
 		return "", err
 	}
 
-	text := syscall.UTF16ToString((*[1 << 20]uint16)(unsafe.Pointer(l))[:])
+	text := string((*[1 << 20]byte)(unsafe.Pointer(l))[:(size - 1)])
 
 	r, _, err := globalUnlock.Call(h)
 	if r == 0 {
@@ -77,25 +93,25 @@ func readAll() (string, error) {
 }
 
 func writeAll(text string) error {
+	return writeAllWithFormat(text, cfText)
+}
+
+func writeAllWithFormat(text string, cf uintptr) error {
 	err := waitOpenClipboard()
 	if err != nil {
 		return err
 	}
 	defer closeClipboard.Call()
 
-	r, _, err := emptyClipboard.Call(0)
-	if r == 0 {
-		return err
-	}
-
-	data := syscall.StringToUTF16(text)
+	data := syscall.StringByteSlice(text)
 
 	// "If the hMem parameter identifies a memory object, the object must have
 	// been allocated using the function with the GMEM_MOVEABLE flag."
-	h, _, err := globalAlloc.Call(gmemMoveable, uintptr(len(data)*int(unsafe.Sizeof(data[0]))))
+	h, _, err := globalAlloc.Call(gmemMoveable, uintptr(len(data)))
 	if h == 0 {
 		return err
 	}
+
 	defer func() {
 		if h != 0 {
 			globalFree.Call(h)
@@ -107,7 +123,7 @@ func writeAll(text string) error {
 		return err
 	}
 
-	r, _, err = lstrcpy.Call(l, uintptr(unsafe.Pointer(&data[0])))
+	r, _, err := memcpy.Call(l, uintptr(unsafe.Pointer(&data[0])), uintptr(len(data)))
 	if r == 0 {
 		return err
 	}
@@ -119,10 +135,40 @@ func writeAll(text string) error {
 		}
 	}
 
-	r, _, err = setClipboardData.Call(cfUnicodetext, h)
+	r, _, err = setClipboardData.Call(cf, h)
 	if r == 0 {
 		return err
 	}
+
 	h = 0 // suppress deferred cleanup
 	return nil
 }
+
+func getClipboardFormat(text string) (uintptr, error) {
+	ptr, err := syscall.UTF16PtrFromString(text)
+	if err != nil {
+		return 0, err
+	}
+
+	cf, _, err := registerClipboardFormat.Call(uintptr(unsafe.Pointer(ptr)))
+	if cf == 0 {
+		return 0, err
+	}
+
+	return cf, nil
+}
+
+func clearClipboard() error {
+	err := waitOpenClipboard()
+	if err != nil {
+		return err
+	}
+	defer closeClipboard.Call()
+
+	r, _, err := emptyClipboard.Call()
+	if r == 0 {
+		return err
+	}
+
+	return nil
+}

cmd/goclip/.gitignore

@@ -0,0 +1,3 @@
+bin
+goclip
+goclip.exe