Terminate the device process gracefully

Call shutdown() on the device socket to make the device process finish
its execution quickly and gracefully, without killing it.

app/src/net.c

@@ -71,3 +71,7 @@ ssize_t net_send_all(socket_t socket, void *buf, size_t len) {
     }
     return w;
 }
+
+SDL_bool net_shutdown(socket_t socket, int how) {
+    return !shutdown(socket, how);
+}

app/src/net.h

@@ -6,10 +6,14 @@
 
 #ifdef __WINDOWS__
 # include <winsock2.h>
+  #define SHUT_RD SD_RECEIVE
+  #define SHUT_WR SD_SEND
+  #define SHUT_RDWR SD_BOTH
   typedef SIZE_T size_t;
   typedef SSIZE_T ssize_t;
   typedef SOCKET socket_t;
 #else
+# include <sys/socket.h>
 # define INVALID_SOCKET -1
   typedef int socket_t;
 #endif
@@ -25,6 +29,8 @@ ssize_t net_recv(socket_t socket, void *buf, size_t len);
 ssize_t net_recv_all(socket_t socket, void *buf, size_t len);
 ssize_t net_send(socket_t socket, void *buf, size_t len);
 ssize_t net_send_all(socket_t socket, void *buf, size_t len);
+// how is SHUT_RD (read), SHUT_WR (write) or SHUT_RDWR (both)
+SDL_bool net_shutdown(socket_t socket, int how);
 void net_close(socket_t socket);
 
 #endif

app/src/scrcpy.c

@@ -164,7 +164,7 @@ finally_destroy_controller:
     controller_destroy(&controller);
 finally_stop_decoder:
     decoder_stop(&decoder);
-    // kill the server before decoder_join() to wake up the decoder
+    // stop the server before decoder_join() to wake up the decoder
     server_stop(&server, serial);
     decoder_join(&decoder);
 finally_destroy_frames:

app/src/server.c

@@ -7,6 +7,7 @@
 
 #include "config.h"
 #include "log.h"
+#include "net.h"
 
 #define SOCKET_NAME "scrcpy"
 
@@ -56,12 +57,6 @@ static process_t execute_server(const char *serial, Uint16 max_size, Uint32 bit_
     return adb_execute(serial, cmd, sizeof(cmd) / sizeof(cmd[0]));
 }
 
-static void terminate_server(process_t server) {
-    if (!cmd_terminate(server)) {
-        LOGE("Could not terminate server: %s", strerror(errno));
-    }
-}
-
 static socket_t listen_on_port(Uint16 port) {
 #define IPV4_LOCALHOST 0x7F000001
     return net_listen(IPV4_LOCALHOST, port, 1);
@@ -126,7 +121,15 @@ socket_t server_connect_to(struct server *server, const char *serial, Uint32 tim
 
 void server_stop(struct server *server, const char *serial) {
     SDL_assert(server->process != PROCESS_NONE);
-    terminate_server(server->process);
+
+    if (server->device_socket != INVALID_SOCKET) {
+        // shutdown the socket to finish the device process gracefully
+        net_shutdown(server->device_socket, SHUT_RDWR);
+    }
+
+    LOGD("Waiting the server to complete execution on the device...");
+    cmd_simple_wait(server->process, NULL); // ignore exit code
+    LOGD("Server terminated");
 
     if (server->adb_reverse_enabled) {
         // ignore failure

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

@@ -21,7 +21,8 @@ public final class ScrCpyServer {
                 // synchronous
                 screenEncoder.streamScreen(device, connection.getOutputStream());
             } catch (IOException e) {
-                Ln.w("Screen streaming stopped");
+                // this is expected on close
+                Ln.d("Screen streaming stopped");
             }
         }
     }
@@ -33,7 +34,8 @@ public final class ScrCpyServer {
                 try {
                     new EventController(device, connection).control();
                 } catch (IOException e) {
-                    Ln.w("Event controller stopped");
+                    // this is expected on close
+                    Ln.d("Event controller stopped");
                 }
             }
         }).start();