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;
 }