Terminate on controller error

This is particularly important to react to server socket disconnection
since video and audio may be disabled.

PR #4868 <https://github.com/Genymobile/scrcpy/pull/4868>

app/src/cli.c

@@ -2585,6 +2585,11 @@ parse_args_with_getopt(struct scrcpy_cli_args *args, int argc, char *argv[],
 
 #ifdef HAVE_V4L2
     if (v4l2) {
+        if (!opts->video) {
+            LOGE("V4L2 sink requires video capture, but --no-video was set.");
+            return false;
+        }
+
         if (opts->lock_video_orientation ==
                 SC_LOCK_VIDEO_ORIENTATION_UNLOCKED) {
             LOGI("Video orientation is locked for v4l2 sink. "
@@ -2613,9 +2618,8 @@ parse_args_with_getopt(struct scrcpy_cli_args *args, int argc, char *argv[],
             if (otg) {
                 opts->mouse_input_mode = SC_MOUSE_INPUT_MODE_AOA;
             } else if (!opts->video_playback) {
-                LOGI("No video mirroring, SDK mouse disabled (you might want "
-                     "--mouse=uhid)");
-                opts->mouse_input_mode = SC_MOUSE_INPUT_MODE_DISABLED;
+                LOGI("No video mirroring, mouse mode switched to UHID");
+                opts->mouse_input_mode = SC_MOUSE_INPUT_MODE_UHID;
             } else {
                 opts->mouse_input_mode = SC_MOUSE_INPUT_MODE_SDK;
             }

app/src/controller.c

@@ -6,8 +6,19 @@
 
 #define SC_CONTROL_MSG_QUEUE_MAX 64
 
+static void
+sc_controller_receiver_on_error(struct sc_receiver *receiver, void *userdata) {
+    (void) receiver;
+
+    struct sc_controller *controller = userdata;
+    // Forward the event to the controller listener
+    controller->cbs->on_error(controller, controller->cbs_userdata);
+}
+
 bool
-sc_controller_init(struct sc_controller *controller, sc_socket control_socket) {
+sc_controller_init(struct sc_controller *controller, sc_socket control_socket,
+                   const struct sc_controller_callbacks *cbs,
+                   void *cbs_userdata) {
     sc_vecdeque_init(&controller->queue);
 
     bool ok = sc_vecdeque_reserve(&controller->queue, SC_CONTROL_MSG_QUEUE_MAX);
@@ -15,7 +26,12 @@ sc_controller_init(struct sc_controller *controller, sc_socket control_socket) {
         return false;
     }
 
-    ok = sc_receiver_init(&controller->receiver, control_socket);
+    static const struct sc_receiver_callbacks receiver_cbs = {
+        .on_error = sc_controller_receiver_on_error,
+    };
+
+    ok = sc_receiver_init(&controller->receiver, control_socket, &receiver_cbs,
+                          controller);
     if (!ok) {
         sc_vecdeque_destroy(&controller->queue);
         return false;
@@ -39,6 +55,10 @@ sc_controller_init(struct sc_controller *controller, sc_socket control_socket) {
     controller->control_socket = control_socket;
     controller->stopped = false;
 
+    assert(cbs && cbs->on_error);
+    controller->cbs = cbs;
+    controller->cbs_userdata = cbs_userdata;
+
     return true;
 }
 
@@ -125,10 +145,16 @@ run_controller(void *data) {
         sc_control_msg_destroy(&msg);
         if (!ok) {
             LOGD("Could not write msg to socket");
-            break;
+            goto error;
         }
     }
+
     return 0;
+
+error:
+    controller->cbs->on_error(controller, controller->cbs_userdata);
+
+    return 1; // ignored
 }
 
 bool

app/src/controller.h

@@ -22,10 +22,19 @@ struct sc_controller {
     bool stopped;
     struct sc_control_msg_queue queue;
     struct sc_receiver receiver;
+
+    const struct sc_controller_callbacks *cbs;
+    void *cbs_userdata;
+};
+
+struct sc_controller_callbacks {
+    void (*on_error)(struct sc_controller *controller, void *userdata);
 };
 
 bool
-sc_controller_init(struct sc_controller *controller, sc_socket control_socket);
+sc_controller_init(struct sc_controller *controller, sc_socket control_socket,
+                   const struct sc_controller_callbacks *cbs,
+                   void *cbs_userdata);
 
 void
 sc_controller_configure(struct sc_controller *controller,

app/src/display.c

@@ -23,12 +23,6 @@ sc_display_init_novideo_icon(struct sc_display *display,
         return false;
     }
 
-    SDL_RenderClear(display->renderer);
-    if (display->texture) {
-        SDL_RenderCopy(display->renderer, display->texture, NULL, NULL);
-    }
-    SDL_RenderPresent(display->renderer);
-
     return true;
 }
 

app/src/events.h

@@ -7,3 +7,4 @@
 #define SC_EVENT_RECORDER_ERROR           (SDL_USEREVENT + 6)
 #define SC_EVENT_SCREEN_INIT_SIZE         (SDL_USEREVENT + 7)
 #define SC_EVENT_TIME_LIMIT_REACHED       (SDL_USEREVENT + 8)
+#define SC_EVENT_CONTROLLER_ERROR         (SDL_USEREVENT + 9)

app/src/input_manager.c

@@ -748,7 +748,8 @@ sc_input_manager_process_mouse_button(struct sc_input_manager *im,
         }
 
         // double-click on black borders resize to fit the device screen
-        if (event->button == SDL_BUTTON_LEFT && event->clicks == 2) {
+        bool video = im->screen->video;
+        if (video && event->button == SDL_BUTTON_LEFT && event->clicks == 2) {
             int32_t x = event->x;
             int32_t y = event->y;
             sc_screen_hidpi_scale_coords(im->screen, &x, &y);

app/src/receiver.c

@@ -10,7 +10,8 @@
 #include "util/str.h"
 
 bool
-sc_receiver_init(struct sc_receiver *receiver, sc_socket control_socket) {
+sc_receiver_init(struct sc_receiver *receiver, sc_socket control_socket,
+                 const struct sc_receiver_callbacks *cbs, void *cbs_userdata) {
     bool ok = sc_mutex_init(&receiver->mutex);
     if (!ok) {
         return false;
@@ -20,6 +21,10 @@ sc_receiver_init(struct sc_receiver *receiver, sc_socket control_socket) {
     receiver->acksync = NULL;
     receiver->uhid_devices = NULL;
 
+    assert(cbs && cbs->on_error);
+    receiver->cbs = cbs;
+    receiver->cbs_userdata = cbs_userdata;
+
     return true;
 }
 
@@ -152,6 +157,8 @@ run_receiver(void *data) {
         }
     }
 
+    receiver->cbs->on_error(receiver, receiver->cbs_userdata);
+
     return 0;
 }
 

app/src/receiver.h

@@ -19,10 +19,18 @@ struct sc_receiver {
 
     struct sc_acksync *acksync;
     struct sc_uhid_devices *uhid_devices;
+
+    const struct sc_receiver_callbacks *cbs;
+    void *cbs_userdata;
+};
+
+struct sc_receiver_callbacks {
+    void (*on_error)(struct sc_receiver *receiver, void *userdata);
 };
 
 bool
-sc_receiver_init(struct sc_receiver *receiver, sc_socket control_socket);
+sc_receiver_init(struct sc_receiver *receiver, sc_socket control_socket,
+                 const struct sc_receiver_callbacks *cbs, void *cbs_userdata);
 
 void
 sc_receiver_destroy(struct sc_receiver *receiver);

app/src/scrcpy.c

@@ -174,6 +174,9 @@ event_loop(struct scrcpy *s) {
             case SC_EVENT_DEMUXER_ERROR:
                 LOGE("Demuxer error");
                 return SCRCPY_EXIT_FAILURE;
+            case SC_EVENT_CONTROLLER_ERROR:
+                LOGE("Controller error");
+                return SCRCPY_EXIT_FAILURE;
             case SC_EVENT_RECORDER_ERROR:
                 LOGE("Recorder error");
                 return SCRCPY_EXIT_FAILURE;
@@ -265,6 +268,16 @@ sc_audio_demuxer_on_ended(struct sc_demuxer *demuxer,
     }
 }
 
+static void
+sc_controller_on_error(struct sc_controller *controller, void *userdata) {
+    // Note: this function may be called twice, once from the controller thread
+    // and once from the receiver thread
+    (void) controller;
+    (void) userdata;
+
+    PUSH_EVENT(SC_EVENT_CONTROLLER_ERROR);
+}
+
 static void
 sc_server_on_connection_failed(struct sc_server *server, void *userdata) {
     (void) server;
@@ -408,7 +421,7 @@ scrcpy(struct scrcpy_options *options) {
         return SCRCPY_EXIT_FAILURE;
     }
 
-    if (options->video_playback) {
+    if (options->window) {
         // Set hints before starting the server thread to avoid race conditions
         // in SDL
         sdl_set_hints(options->render_driver);
@@ -553,7 +566,12 @@ scrcpy(struct scrcpy_options *options) {
     struct sc_mouse_processor *mp = NULL;
 
     if (options->control) {
-        if (!sc_controller_init(&s->controller, s->server.control_socket)) {
+        static const struct sc_controller_callbacks controller_cbs = {
+            .on_error = sc_controller_on_error,
+        };
+
+        if (!sc_controller_init(&s->controller, s->server.control_socket,
+            &controller_cbs, NULL)) {
             goto end;
         }
         controller_initialized = true;

app/src/screen.c

@@ -259,6 +259,13 @@ sc_screen_render(struct sc_screen *screen, bool update_content_rect) {
     (void) res; // any error already logged
 }
 
+static void
+sc_screen_render_novideo(struct sc_screen *screen) {
+    enum sc_display_result res =
+        sc_display_render(&screen->display, NULL, SC_ORIENTATION_0);
+    (void) res; // any error already logged
+}
+
 #if defined(__APPLE__) || defined(__WINDOWS__)
 # define CONTINUOUS_RESIZING_WORKAROUND
 #endif
@@ -371,6 +378,7 @@ sc_screen_init(struct sc_screen *screen,
     screen->mouse_capture_key_pressed = 0;
     screen->paused = false;
     screen->resume_frame = NULL;
+    screen->orientation = SC_ORIENTATION_0;
 
     screen->video = params->video;
 
@@ -390,10 +398,12 @@ sc_screen_init(struct sc_screen *screen,
         goto error_destroy_frame_buffer;
     }
 
-    screen->orientation = params->orientation;
-    if (screen->orientation != SC_ORIENTATION_0) {
-        LOGI("Initial display orientation set to %s",
-             sc_orientation_get_name(screen->orientation));
+    if (screen->video) {
+        screen->orientation = params->orientation;
+        if (screen->orientation != SC_ORIENTATION_0) {
+            LOGI("Initial display orientation set to %s",
+                 sc_orientation_get_name(screen->orientation));
+        }
     }
 
     uint32_t window_flags = SDL_WINDOW_ALLOW_HIGHDPI;
@@ -403,6 +413,11 @@ sc_screen_init(struct sc_screen *screen,
     if (params->window_borderless) {
         window_flags |= SDL_WINDOW_BORDERLESS;
     }
+    if (params->video) {
+        // The window will be shown on first frame
+        window_flags |= SDL_WINDOW_HIDDEN
+                      | SDL_WINDOW_RESIZABLE;
+    }
 
     const char *title = params->window_title;
     assert(title);
@@ -411,22 +426,17 @@ sc_screen_init(struct sc_screen *screen,
     int y = SDL_WINDOWPOS_UNDEFINED;
     int width = 256;
     int height = 256;
-    if (params->video) {
-        // The window will be shown on first frame
-        window_flags |= SDL_WINDOW_HIDDEN
-                      | SDL_WINDOW_RESIZABLE;
-        if (params->window_x != SC_WINDOW_POSITION_UNDEFINED) {
-            x = params->window_x;
-        }
-        if (params->window_y != SC_WINDOW_POSITION_UNDEFINED) {
-            y = params->window_y;
-        }
-        if (params->window_width) {
-            width = params->window_width;
-        }
-        if (params->window_height) {
-            height = params->window_height;
-        }
+    if (params->window_x != SC_WINDOW_POSITION_UNDEFINED) {
+        x = params->window_x;
+    }
+    if (params->window_y != SC_WINDOW_POSITION_UNDEFINED) {
+        y = params->window_y;
+    }
+    if (params->window_width) {
+        width = params->window_width;
+    }
+    if (params->window_height) {
+        height = params->window_height;
     }
 
     // The window will be positioned and sized on first video frame
@@ -449,8 +459,9 @@ sc_screen_init(struct sc_screen *screen,
     }
 
     SDL_Surface *icon_novideo = params->video ? NULL : icon;
+    bool mipmaps = params->video && params->mipmaps;
     ok = sc_display_init(&screen->display, screen->window, icon_novideo,
-                         params->mipmaps);
+                         mipmaps);
     if (icon) {
         scrcpy_icon_destroy(icon);
     }
@@ -857,6 +868,11 @@ sc_screen_handle_event(struct sc_screen *screen, const SDL_Event *event) {
             return true;
         }
         case SDL_WINDOWEVENT:
+            if (!screen->video
+                    && event->window.event == SDL_WINDOWEVENT_EXPOSED) {
+                sc_screen_render_novideo(screen);
+            }
+
             // !video implies !has_frame
             assert(screen->video || !screen->has_frame);
             if (!screen->has_frame) {

doc/control.md

@@ -17,11 +17,20 @@ Read [keyboard](keyboard.md) and [mouse](mouse.md).
 
 ## Control only
 
-To control only with UHID mouse and keyboard:
+To control the device without mirroring:
 
 ```bash
-scrcpy --no-video --no-audio --keyboard=uhid --mouse=uhid
-scrcpy --no-video --no-audio -KM  # short version
+scrcpy --no-video --no-audio
+```
+
+By default, mouse mode is switched to UHID if video mirroring is disabled (a
+relative mouse mode is required).
+
+To also use a UHID keyboard, set it explicitly:
+
+```bash
+scrcpy --no-video --no-audio --keyboard=uhid
+scrcpy --no-video --no-audio -K  # short version
 ```
 
 

doc/otg.md

@@ -44,8 +44,8 @@ See [FAQ](/FAQ.md#otg-issues-on-windows).
 Note that the purpose of OTG is to control the device without USB debugging
 (adb).
 
-If you want to only control the device without mirroring while USB debugging is
-enabled, then OTG mode is not necessary.
+If you want to solely control the device without mirroring while USB debugging
+is enabled, then OTG mode is not necessary.
 
 Instead, disable video and audio, and select UHID (or AOA):