Add device clipboard set acknowledgement

Add a device message type so that the device could send acknowledgements
for SET_CLIPBOARD requests.

PR #2814 <https://github.com/Genymobile/scrcpy/pull/2814>

app/src/device_msg.c

@@ -1,5 +1,6 @@
 #include "device_msg.h"
 
+#include <stdint.h>
 #include <stdlib.h>
 #include <string.h>
 
@@ -34,6 +35,11 @@ device_msg_deserialize(const unsigned char *buf, size_t len,
             msg->clipboard.text = text;
             return 5 + clipboard_len;
         }
+        case DEVICE_MSG_TYPE_ACK_CLIPBOARD: {
+            uint64_t sequence = buffer_read64be(&buf[1]);
+            msg->ack_clipboard.sequence = sequence;
+            return 9;
+        }
         default:
             LOGW("Unknown device message type: %d", (int) msg->type);
             return -1; // error, we cannot recover

app/src/device_msg.h

@@ -13,6 +13,7 @@
 
 enum device_msg_type {
     DEVICE_MSG_TYPE_CLIPBOARD,
+    DEVICE_MSG_TYPE_ACK_CLIPBOARD,
 };
 
 struct device_msg {
@@ -21,6 +22,9 @@ struct device_msg {
         struct {
             char *text; // owned, to be freed by free()
         } clipboard;
+        struct {
+            uint64_t sequence;
+        } ack_clipboard;
     };
 };
 

app/src/receiver.c

@@ -37,6 +37,9 @@ process_msg(struct device_msg *msg) {
             SDL_SetClipboardText(msg->clipboard.text);
             break;
         }
+        case DEVICE_MSG_TYPE_ACK_CLIPBOARD:
+            // TODO
+            break;
     }
 }
 

app/tests/test_device_msg_deserialize.c

@@ -47,11 +47,26 @@ static void test_deserialize_clipboard_big(void) {
     device_msg_destroy(&msg);
 }
 
+static void test_deserialize_ack_set_clipboard(void) {
+    const unsigned char input[] = {
+        DEVICE_MSG_TYPE_ACK_CLIPBOARD,
+        0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, // sequence
+    };
+
+    struct device_msg msg;
+    ssize_t r = device_msg_deserialize(input, sizeof(input), &msg);
+    assert(r == 9);
+
+    assert(msg.type == DEVICE_MSG_TYPE_ACK_CLIPBOARD);
+    assert(msg.ack_clipboard.sequence == UINT64_C(0x0102030405060708));
+}
+
 int main(int argc, char *argv[]) {
     (void) argc;
     (void) argv;
 
     test_deserialize_clipboard();
     test_deserialize_clipboard_big();
+    test_deserialize_ack_set_clipboard();
     return 0;
 }

server/src/main/java/com/genymobile/scrcpy/DeviceMessage.java

@@ -3,9 +3,11 @@ package com.genymobile.scrcpy;
 public final class DeviceMessage {
 
     public static final int TYPE_CLIPBOARD = 0;
+    public static final int TYPE_ACK_CLIPBOARD = 1;
 
     private int type;
     private String text;
+    private long sequence;
 
     private DeviceMessage() {
     }
@@ -17,6 +19,13 @@ public final class DeviceMessage {
         return event;
     }
 
+    public static DeviceMessage createAckClipboard(long sequence) {
+        DeviceMessage event = new DeviceMessage();
+        event.type = TYPE_ACK_CLIPBOARD;
+        event.sequence = sequence;
+        return event;
+    }
+
     public int getType() {
         return type;
     }
@@ -24,4 +33,8 @@ public final class DeviceMessage {
     public String getText() {
         return text;
     }
+
+    public long getSequence() {
+        return sequence;
+    }
 }

server/src/main/java/com/genymobile/scrcpy/DeviceMessageWriter.java

@@ -15,7 +15,7 @@ public class DeviceMessageWriter {
 
     public void writeTo(DeviceMessage msg, OutputStream output) throws IOException {
         buffer.clear();
-        buffer.put((byte) DeviceMessage.TYPE_CLIPBOARD);
+        buffer.put((byte) msg.getType());
         switch (msg.getType()) {
             case DeviceMessage.TYPE_CLIPBOARD:
                 String text = msg.getText();
@@ -25,6 +25,10 @@ public class DeviceMessageWriter {
                 buffer.put(raw, 0, len);
                 output.write(rawBuffer, 0, buffer.position());
                 break;
+            case DeviceMessage.TYPE_ACK_CLIPBOARD:
+                buffer.putLong(msg.getSequence());
+                output.write(rawBuffer, 0, buffer.position());
+                break;
             default:
                 Ln.w("Unknown device message: " + msg.getType());
                 break;

server/src/test/java/com/genymobile/scrcpy/DeviceMessageWriterTest.java

@@ -32,4 +32,24 @@ public class DeviceMessageWriterTest {
 
         Assert.assertArrayEquals(expected, actual);
     }
+
+    @Test
+    public void testSerializeAckSetClipboard() throws IOException {
+        DeviceMessageWriter writer = new DeviceMessageWriter();
+
+        ByteArrayOutputStream bos = new ByteArrayOutputStream();
+        DataOutputStream dos = new DataOutputStream(bos);
+        dos.writeByte(DeviceMessage.TYPE_ACK_CLIPBOARD);
+        dos.writeLong(0x0102030405060708L);
+
+        byte[] expected = bos.toByteArray();
+
+        DeviceMessage msg = DeviceMessage.createAckClipboard(0x0102030405060708L);
+        bos = new ByteArrayOutputStream();
+        writer.writeTo(msg, bos);
+
+        byte[] actual = bos.toByteArray();
+
+        Assert.assertArrayEquals(expected, actual);
+    }
 }