Add option to mirror in read-only

Add an option to disable device control: -n/--no-control.

README.md

@@ -247,6 +247,17 @@ _scrcpy_ window.
 There is no visual feedback, a log is printed to the console.
 
 
+### Read-only
+
+To disable controls (everything which can interact with the device: input keys,
+mouse events, drag&drop files):
+
+```bash
+scrcpy --no-control
+scrcpy -n
+```
+
+
 ### Forward audio
 
 Audio is not forwarded by _scrcpy_.

app/src/input_manager.c

@@ -202,6 +202,9 @@ input_manager_process_key(struct input_manager *input_manager,
         return;
     }
 
+    // false if the user requested not to interact with the device
+    SDL_bool control = input_manager->control;
+
     // capture all Ctrl events
     if (ctrl | meta) {
         SDL_Keycode keycode = event->keysym.sym;
@@ -210,36 +213,36 @@ input_manager_process_key(struct input_manager *input_manager,
         SDL_bool shift = event->keysym.mod & (KMOD_LSHIFT | KMOD_RSHIFT);
         switch (keycode) {
             case SDLK_h:
-                if (ctrl && !meta && !shift && !repeat) {
+                if (control && ctrl && !meta && !shift && !repeat) {
                     action_home(input_manager->controller, action);
                 }
                 return;
             case SDLK_b: // fall-through
             case SDLK_BACKSPACE:
-                if (ctrl && !meta && !shift && !repeat) {
+                if (control && ctrl && !meta && !shift && !repeat) {
                     action_back(input_manager->controller, action);
                 }
                 return;
             case SDLK_s:
-                if (ctrl && !meta && !shift && !repeat) {
+                if (control && ctrl && !meta && !shift && !repeat) {
                     action_app_switch(input_manager->controller, action);
                 }
                 return;
             case SDLK_m:
-                if (ctrl && !meta && !shift && !repeat) {
+                if (control && ctrl && !meta && !shift && !repeat) {
                     action_menu(input_manager->controller, action);
                 }
                 return;
             case SDLK_p:
-                if (ctrl && !meta && !shift && !repeat) {
+                if (control && ctrl && !meta && !shift && !repeat) {
                     action_power(input_manager->controller, action);
                 }
                 return;
             case SDLK_DOWN:
 #ifdef __APPLE__
-                if (!ctrl && meta && !shift) {
+                if (control && !ctrl && meta && !shift) {
 #else
-                if (ctrl && !meta && !shift) {
+                if (control && ctrl && !meta && !shift) {
 #endif
                     // forward repeated events
                     action_volume_down(input_manager->controller, action);
@@ -247,16 +250,16 @@ input_manager_process_key(struct input_manager *input_manager,
                 return;
             case SDLK_UP:
 #ifdef __APPLE__
-                if (!ctrl && meta && !shift) {
+                if (control && !ctrl && meta && !shift) {
 #else
-                if (ctrl && !meta && !shift) {
+                if (control && ctrl && !meta && !shift) {
 #endif
                     // forward repeated events
                     action_volume_up(input_manager->controller, action);
                 }
                 return;
             case SDLK_v:
-                if (ctrl && !meta && !shift && !repeat
+                if (control && ctrl && !meta && !shift && !repeat
                         && event->type == SDL_KEYDOWN) {
                     clipboard_paste(input_manager->controller);
                 }
@@ -286,7 +289,8 @@ input_manager_process_key(struct input_manager *input_manager,
                 }
                 return;
             case SDLK_n:
-                if (ctrl && !meta && !repeat && event->type == SDL_KEYDOWN) {
+                if (control && ctrl && !meta
+                        && !repeat && event->type == SDL_KEYDOWN) {
                     if (shift) {
                         collapse_notification_panel(input_manager->controller);
                     } else {
@@ -299,6 +303,10 @@ input_manager_process_key(struct input_manager *input_manager,
         return;
     }
 
+    if (!control) {
+        return;
+    }
+
     struct control_event control_event;
     if (input_key_from_sdl_to_android(event, &control_event)) {
         if (!controller_push_event(input_manager->controller, &control_event)) {
@@ -334,18 +342,21 @@ is_outside_device_screen(struct input_manager *input_manager, int x, int y)
 void
 input_manager_process_mouse_button(struct input_manager *input_manager,
                                    const SDL_MouseButtonEvent *event) {
+    // false if the user requested not to interact with the device
+    SDL_bool control = input_manager->control;
+
     if (event->type == SDL_MOUSEBUTTONDOWN) {
-        if (event->button == SDL_BUTTON_RIGHT) {
+        if (control && event->button == SDL_BUTTON_RIGHT) {
             press_back_or_turn_screen_on(input_manager->controller);
             return;
         }
-        if (event->button == SDL_BUTTON_MIDDLE) {
+        if (control && event->button == SDL_BUTTON_MIDDLE) {
             action_home(input_manager->controller, ACTION_DOWN | ACTION_UP);
             return;
         }
         // double-click on black borders resize to fit the device screen
         if (event->button == SDL_BUTTON_LEFT && event->clicks == 2) {
-            SDL_bool outside= is_outside_device_screen(input_manager,
+            SDL_bool outside = is_outside_device_screen(input_manager,
                                                         event->x,
                                                         event->y);
             if (outside) {
@@ -356,6 +367,10 @@ input_manager_process_mouse_button(struct input_manager *input_manager,
         // otherwise, send the click event to the device
     }
 
+    if (!control) {
+        return;
+    }
+
     struct control_event control_event;
     if (mouse_button_from_sdl_to_android(event,
                                          input_manager->screen->frame_size,

app/src/input_manager.h

@@ -11,6 +11,7 @@ struct input_manager {
     struct controller *controller;
     struct video_buffer *video_buffer;
     struct screen *screen;
+    SDL_bool control;
 };
 
 void

app/src/main.c

@@ -16,6 +16,7 @@ struct args {
     const char *record_filename;
     enum recorder_format record_format;
     SDL_bool fullscreen;
+    SDL_bool no_control;
     SDL_bool no_display;
     SDL_bool help;
     SDL_bool version;
@@ -58,6 +59,9 @@ static void usage(const char *arg0) {
         "        is preserved.\n"
         "        Default is %d%s.\n"
         "\n"
+        "    -n, --no-control\n"
+        "        Disable device control (mirror the device in read-only).\n"
+        "\n"
         "    -N, --no-display\n"
         "        Do not display device (only when screen recording is\n"
         "        enabled).\n"
@@ -277,6 +281,7 @@ parse_args(struct args *args, int argc, char *argv[]) {
         {"fullscreen",    no_argument,       NULL, 'f'},
         {"help",          no_argument,       NULL, 'h'},
         {"max-size",      required_argument, NULL, 'm'},
+        {"no-control",    no_argument,       NULL, 'n'},
         {"no-display",    no_argument,       NULL, 'N'},
         {"port",          required_argument, NULL, 'p'},
         {"record",        required_argument, NULL, 'r'},
@@ -287,7 +292,7 @@ parse_args(struct args *args, int argc, char *argv[]) {
         {NULL,            0,                 NULL, 0  },
     };
     int c;
-    while ((c = getopt_long(argc, argv, "b:c:fF:hm:Np:r:s:tTv", long_options,
+    while ((c = getopt_long(argc, argv, "b:c:fF:hm:nNp:r:s:tTv", long_options,
                             NULL)) != -1) {
         switch (c) {
             case 'b':
@@ -314,6 +319,9 @@ parse_args(struct args *args, int argc, char *argv[]) {
                     return SDL_FALSE;
                 }
                 break;
+            case 'n':
+                args->no_control = SDL_TRUE;
+                break;
             case 'N':
                 args->no_display = SDL_TRUE;
                 break;
@@ -396,6 +404,7 @@ main(int argc, char *argv[]) {
         .max_size = DEFAULT_MAX_SIZE,
         .bit_rate = DEFAULT_BIT_RATE,
         .always_on_top = SDL_FALSE,
+        .no_control = SDL_FALSE,
         .no_display = SDL_FALSE,
     };
     if (!parse_args(&args, argc, argv)) {
@@ -435,6 +444,7 @@ main(int argc, char *argv[]) {
         .show_touches = args.show_touches,
         .fullscreen = args.fullscreen,
         .always_on_top = args.always_on_top,
+        .no_control = args.no_control,
         .no_display = args.no_display,
     };
     int res = scrcpy(&options) ? 0 : 1;

app/src/scrcpy.c

@@ -39,6 +39,7 @@ static struct input_manager input_manager = {
     .controller = &controller,
     .video_buffer = &video_buffer,
     .screen = &screen,
+    .control = SDL_TRUE,
 };
 
 #if defined(__APPLE__) || defined(__WINDOWS__)
@@ -75,7 +76,7 @@ enum event_result {
 };
 
 static enum event_result
-handle_event(SDL_Event *event) {
+handle_event(SDL_Event *event, SDL_bool control) {
     switch (event->type) {
         case EVENT_STREAM_STOPPED:
             LOGD("Video stream stopped");
@@ -102,23 +103,39 @@ handle_event(SDL_Event *event) {
             }
             break;
         case SDL_TEXTINPUT:
+            if (!control) {
+                break;
+            }
             input_manager_process_text_input(&input_manager, &event->text);
             break;
         case SDL_KEYDOWN:
         case SDL_KEYUP:
+            // some key events do not interact with the device, so process the
+            // event even if control is disabled
             input_manager_process_key(&input_manager, &event->key);
             break;
         case SDL_MOUSEMOTION:
+            if (!control) {
+                break;
+            }
             input_manager_process_mouse_motion(&input_manager, &event->motion);
             break;
         case SDL_MOUSEWHEEL:
+            if (!control) {
+                break;
+            }
             input_manager_process_mouse_wheel(&input_manager, &event->wheel);
             break;
         case SDL_MOUSEBUTTONDOWN:
         case SDL_MOUSEBUTTONUP:
+            // some mouse events do not interact with the device, so process
+            // the event even if control is disabled
             input_manager_process_mouse_button(&input_manager, &event->button);
             break;
         case SDL_DROPFILE: {
+            if (!control) {
+                break;
+            }
             file_handler_action_t action;
             if (is_apk(event->drop.file)) {
                 action = ACTION_INSTALL_APK;
@@ -133,7 +150,7 @@ handle_event(SDL_Event *event) {
 }
 
 static SDL_bool
-event_loop(SDL_bool display) {
+event_loop(SDL_bool display, SDL_bool control) {
 #ifdef CONTINUOUS_RESIZING_WORKAROUND
     if (display) {
         SDL_AddEventWatch(event_watcher, NULL);
@@ -141,7 +158,7 @@ event_loop(SDL_bool display) {
 #endif
     SDL_Event event;
     while (SDL_WaitEvent(&event)) {
-        enum event_result result = handle_event(&event);
+        enum event_result result = handle_event(&event, control);
         switch (result) {
             case EVENT_RESULT_STOPPED_BY_USER:
                 return SDL_TRUE;
@@ -248,6 +265,9 @@ scrcpy(const struct scrcpy_options *options) {
     }
 
     SDL_bool display = !options->no_display;
+    SDL_bool control = !options->no_control;
+
+    input_manager.control = control;
 
     struct decoder *dec = NULL;
     if (display) {
@@ -257,7 +277,7 @@ scrcpy(const struct scrcpy_options *options) {
             goto finally_destroy_server;
         }
 
-        if (!file_handler_init(&file_handler, server.serial)) {
+        if (control && !file_handler_init(&file_handler, server.serial)) {
             ret = SDL_FALSE;
             server_stop(&server);
             goto finally_destroy_video_buffer;
@@ -293,6 +313,7 @@ scrcpy(const struct scrcpy_options *options) {
     }
 
     if (display) {
+        if (control) {
             if (!controller_init(&controller, device_socket)) {
                 ret = SDL_FALSE;
                 goto finally_stop_stream;
@@ -302,6 +323,7 @@ scrcpy(const struct scrcpy_options *options) {
                 ret = SDL_FALSE;
                 goto finally_destroy_controller;
             }
+        }
 
         if (!screen_init_rendering(&screen, device_name, frame_size,
                                    options->always_on_top)) {
@@ -319,18 +341,18 @@ scrcpy(const struct scrcpy_options *options) {
         show_touches_waited = SDL_TRUE;
     }
 
-    ret = event_loop(display);
+    ret = event_loop(display, control);
     LOGD("quit...");
 
     screen_destroy(&screen);
 
 finally_stop_and_join_controller:
-    if (display) {
+    if (display && control) {
         controller_stop(&controller);
         controller_join(&controller);
     }
 finally_destroy_controller:
-    if (display) {
+    if (display && control) {
         controller_destroy(&controller);
     }
 finally_stop_stream:
@@ -343,7 +365,7 @@ finally_destroy_recorder:
         recorder_destroy(&recorder);
     }
 finally_destroy_file_handler:
-    if (display) {
+    if (display && control) {
         file_handler_stop(&file_handler);
         file_handler_join(&file_handler);
         file_handler_destroy(&file_handler);

app/src/scrcpy.h

@@ -15,6 +15,7 @@ struct scrcpy_options {
     SDL_bool show_touches;
     SDL_bool fullscreen;
     SDL_bool always_on_top;
+    SDL_bool no_control;
     SDL_bool no_display;
 };