From 72ee195693a030990e9965ac93922c9aae32988d Mon Sep 17 00:00:00 2001
From: Romain Vimont <rom@rom1v.com>
Date: Fri, 6 Sep 2024 23:08:08 +0200
Subject: [PATCH] Set clipboard from the main thread

The clipboard changes from the device are received from a separate
thread, but they must be handled from the main thread.

PR #5270 <https://github.com/Genymobile/scrcpy/pull/5270>
---
 app/src/receiver.c | 41 +++++++++++++++++++++++++++++++++--------
 1 file changed, 33 insertions(+), 8 deletions(-)

diff --git a/app/src/receiver.c b/app/src/receiver.c
index 3e572067..2911f8b9 100644
--- a/app/src/receiver.c
+++ b/app/src/receiver.c
@@ -6,8 +6,10 @@
 #include <SDL2/SDL_clipboard.h>
 
 #include "device_msg.h"
+#include "events.h"
 #include "util/log.h"
 #include "util/str.h"
+#include "util/thread.h"
 
 bool
 sc_receiver_init(struct sc_receiver *receiver, sc_socket control_socket,
@@ -33,20 +35,39 @@ sc_receiver_destroy(struct sc_receiver *receiver) {
     sc_mutex_destroy(&receiver->mutex);
 }
 
+static void
+task_set_clipboard(void *userdata) {
+    assert(sc_thread_get_id() == SC_MAIN_THREAD_ID);
+
+    char *text = userdata;
+
+    char *current = SDL_GetClipboardText();
+    bool same = current && !strcmp(current, text);
+    SDL_free(current);
+    if (same) {
+        LOGD("Computer clipboard unchanged");
+    } else {
+        LOGI("Device clipboard copied");
+        SDL_SetClipboardText(text);
+    }
+
+    free(text);
+}
+
 static void
 process_msg(struct sc_receiver *receiver, struct sc_device_msg *msg) {
     switch (msg->type) {
         case DEVICE_MSG_TYPE_CLIPBOARD: {
-            char *current = SDL_GetClipboardText();
-            bool same = current && !strcmp(current, msg->clipboard.text);
-            SDL_free(current);
-            if (same) {
-                LOGD("Computer clipboard unchanged");
+            // Take ownership of the text (do not destroy the msg)
+            char *text = msg->clipboard.text;
+
+            bool ok = sc_post_to_main_thread(task_set_clipboard, text);
+            if (!ok) {
+                LOGW("Could not post clipboard to main thread");
+                free(text);
                 return;
             }
 
-            LOGI("Device clipboard copied");
-            SDL_SetClipboardText(msg->clipboard.text);
             break;
         }
         case DEVICE_MSG_TYPE_ACK_CLIPBOARD:
@@ -64,6 +85,7 @@ process_msg(struct sc_receiver *receiver, struct sc_device_msg *msg) {
             }
 
             sc_acksync_ack(receiver->acksync, msg->ack_clipboard.sequence);
+            // No allocation to free in the msg
             break;
         case DEVICE_MSG_TYPE_UHID_OUTPUT:
             if (sc_get_log_level() <= SC_LOG_LEVEL_VERBOSE) {
@@ -86,6 +108,7 @@ process_msg(struct sc_receiver *receiver, struct sc_device_msg *msg) {
             // Also check at runtime (do not trust the server)
             if (!receiver->uhid_devices) {
                 LOGE("Received unexpected HID output message");
+                sc_device_msg_destroy(msg);
                 return;
             }
 
@@ -99,6 +122,8 @@ process_msg(struct sc_receiver *receiver, struct sc_device_msg *msg) {
             } else {
                 LOGW("No UHID receiver for id %" PRIu16, msg->uhid_output.id);
             }
+
+            sc_device_msg_destroy(msg);
             break;
     }
 }
@@ -117,7 +142,7 @@ process_msgs(struct sc_receiver *receiver, const uint8_t *buf, size_t len) {
         }
 
         process_msg(receiver, &msg);
-        sc_device_msg_destroy(&msg);
+        // the device msg must be destroyed by process_msg()
 
         head += r;
         assert(head <= len);