more logs

The window state may be changed by the window manager without scrcpy
being aware of it (for example the fullscreen mode on macOS).

Check on every "size changed" event whether the fullscreen mode has
changed.

app/src/screen.c

@@ -30,10 +30,10 @@ get_rotated_size(struct size size, int rotation) {
 
 // get the window size in a struct size
 static struct size
-get_window_size(SDL_Window *window) {
+get_window_size(const struct screen *screen) {
     int width;
     int height;
-    SDL_GetWindowSize(window, &width, &height);
+    SDL_GetWindowSize(screen->window, &width, &height);
 
     struct size size;
     size.width = width;
@@ -41,31 +41,12 @@ get_window_size(SDL_Window *window) {
     return size;
 }
 
-// get the windowed window size
-static struct size
-get_windowed_window_size(const struct screen *screen) {
-    if (screen->fullscreen || screen->maximized) {
-        return screen->windowed_window_size;
-    }
-    return get_window_size(screen->window);
-}
-
-// apply the windowed window size if fullscreen and maximized are disabled
-static void
-apply_windowed_size(struct screen *screen) {
-    if (!screen->fullscreen && !screen->maximized) {
-        SDL_SetWindowSize(screen->window, screen->windowed_window_size.width,
-                                          screen->windowed_window_size.height);
-    }
-}
-
 // set the window size to be applied when fullscreen is disabled
 static void
 set_window_size(struct screen *screen, struct size new_size) {
-    // setting the window size during fullscreen is implementation defined,
+    assert(!screen->fullscreen);
-    // so apply the resize only after fullscreen is disabled
+    assert(!screen->maximized);
-    screen->windowed_window_size = new_size;
+    SDL_SetWindowSize(screen->window, new_size.width, new_size.height);
-    apply_windowed_size(screen);
 }
 
 // get the preferred display bounds (i.e. the screen bounds with some margins)
@@ -138,8 +119,8 @@ get_optimal_size(struct size current_size, struct size content_size) {
 // same as get_optimal_size(), but read the current size from the window
 static inline struct size
 get_optimal_window_size(const struct screen *screen, struct size content_size) {
-    struct size windowed_size = get_windowed_window_size(screen);
+    struct size window_size = get_window_size(screen);
-    return get_optimal_size(windowed_size, content_size);
+    return get_optimal_size(window_size, content_size);
 }
 
 // initially, there is no current size, so use the frame size as current size
@@ -308,8 +289,6 @@ screen_init_rendering(struct screen *screen, const char *window_title,
         return false;
     }
 
-    screen->windowed_window_size = window_size;
-
     return true;
 }
 
@@ -331,6 +310,45 @@ screen_destroy(struct screen *screen) {
     }
 }
 
+static void
+resize_for_content(struct screen *screen, struct size old_content_size,
+                                                 struct size new_content_size) {
+    struct size window_size = get_window_size(screen);
+    struct size target_size = {
+        .width = (uint32_t) window_size.width * new_content_size.width
+                / old_content_size.width,
+        .height = (uint32_t) window_size.height * new_content_size.height
+                / old_content_size.height,
+    };
+    target_size = get_optimal_size(target_size, new_content_size);
+    set_window_size(screen, target_size);
+}
+
+static void
+set_content_size(struct screen *screen, struct size new_content_size) {
+    if (!screen->fullscreen && !screen->maximized) {
+        resize_for_content(screen, screen->content_size, new_content_size);
+    } else if (!screen->resize_pending) {
+        // Store the windowed size to be able to compute the optimal size once
+        // fullscreen and maximized are disabled
+        screen->windowed_content_size = screen->content_size;
+        screen->resize_pending = true;
+    }
+
+    screen->content_size = new_content_size;
+}
+
+static void
+apply_pending_resize(struct screen *screen) {
+    assert(!screen->fullscreen);
+    assert(!screen->maximized);
+    if (screen->resize_pending) {
+        resize_for_content(screen, screen->windowed_content_size,
+                                   screen->content_size);
+        screen->resize_pending = false;
+    }
+}
+
 void
 screen_set_rotation(struct screen *screen, unsigned rotation) {
     assert(rotation < 4);
@@ -338,7 +356,6 @@ screen_set_rotation(struct screen *screen, unsigned rotation) {
         return;
     }
 
-    struct size old_content_size = screen->content_size;
     struct size new_content_size =
         get_rotated_size(screen->frame_size, rotation);
 
@@ -349,17 +366,7 @@ screen_set_rotation(struct screen *screen, unsigned rotation) {
         return;
     }
 
-    struct size windowed_size = get_windowed_window_size(screen);
+    set_content_size(screen, new_content_size);
-    struct size target_size = {
-        .width = (uint32_t) windowed_size.width * new_content_size.width
-                / old_content_size.width,
-        .height = (uint32_t) windowed_size.height * new_content_size.height
-                / old_content_size.height,
-    };
-    target_size = get_optimal_size(target_size, new_content_size);
-    set_window_size(screen, target_size);
-
-    screen->content_size = new_content_size;
     screen->rotation = rotation;
     LOGI("Display rotation set to %u", rotation);
 
@@ -383,19 +390,8 @@ prepare_for_frame(struct screen *screen, struct size new_frame_size) {
         // frame dimension changed, destroy texture
         SDL_DestroyTexture(screen->texture);
 
-        struct size content_size = screen->content_size;
+        set_content_size(screen, new_content_size);
-        struct size windowed_size = get_windowed_window_size(screen);
-        struct size target_size = {
-            (uint32_t) windowed_size.width * new_content_size.width
-                    / content_size.width,
-            (uint32_t) windowed_size.height * new_content_size.height
-                    / content_size.height,
-        };
-        target_size = get_optimal_size(target_size, new_content_size);
-        set_window_size(screen, target_size);
-
         screen->frame_size = new_frame_size;
-        screen->content_size = new_content_size;
 
         LOGI("New texture: %" PRIu16 "x%" PRIu16,
                      screen->frame_size.width, screen->frame_size.height);
@@ -478,7 +474,9 @@ screen_switch_fullscreen(struct screen *screen) {
     }
 
     screen->fullscreen = !screen->fullscreen;
-    apply_windowed_size(screen);
+    if (!screen->fullscreen && !screen->maximized) {
+        apply_pending_resize(screen);
+    }
 
     LOGD("Switched to %s mode", screen->fullscreen ? "fullscreen" : "windowed");
     screen_render(screen);
@@ -490,6 +488,9 @@ screen_resize_to_fit(struct screen *screen) {
         return;
     }
 
+    int flags = SDL_GetWindowFlags(screen->window);
+    LOGI("resize to fit (%d 0x%x)", screen->maximized, flags);
+
     if (screen->maximized) {
         SDL_RestoreWindow(screen->window);
         screen->maximized = false;
@@ -498,7 +499,7 @@ screen_resize_to_fit(struct screen *screen) {
     struct size optimal_size =
         get_optimal_window_size(screen, screen->content_size);
     SDL_SetWindowSize(screen->window, optimal_size.width, optimal_size.height);
-    LOGD("Resized to optimal size: %ux%u", optimal_size.width,
+    LOGI("Resized to optimal size: %ux%u", optimal_size.width,
                                            optimal_size.height);
 }
 
@@ -519,44 +520,55 @@ screen_resize_to_pixel_perfect(struct screen *screen) {
                                             content_size.height);
 }
 
+static inline bool
+is_fullscreen(const struct screen *screen) {
+    uint32_t flags = SDL_GetWindowFlags(screen->window);
+    LOGI("flags = 0x%x", flags);
+    return !!(flags & (SDL_WINDOW_FULLSCREEN | SDL_WINDOW_FULLSCREEN_DESKTOP));
+}
+
+static void
+update_fullscreen_state(struct screen *screen) {
+    // There is no SDL event to detect fullscreen changes, so store the
+    // state in a field and compare on every "size changed" event
+    bool fullscreen = is_fullscreen(screen);
+    if (fullscreen != screen->fullscreen) {
+        // Fullscreen state have changed
+        screen->fullscreen = fullscreen;
+        if (!fullscreen && !screen->maximized) {
+            apply_pending_resize(screen);
+        }
+    }
+}
+
 void
 screen_handle_window_event(struct screen *screen,
                            const SDL_WindowEvent *event) {
     switch (event->event) {
         case SDL_WINDOWEVENT_EXPOSED:
+            LOGI("EXPOSED");
             screen_render(screen);
             break;
         case SDL_WINDOWEVENT_SIZE_CHANGED:
-            if (!screen->fullscreen && !screen->maximized) {
+            LOGI("SIZE_CHANGED %dx%d", event->data1, event->data2);
-                // Backup the previous size: if we receive the MAXIMIZED event,
+            //update_fullscreen_state(screen);
-                // then the new size must be ignored (it's the maximized size).
-                // We could not rely on the window flags due to race conditions
-                // (they could be updated asynchronously, at least on X11).
-                screen->windowed_window_size_backup =
-                    screen->windowed_window_size;
-
-                // Save the windowed size, so that it is available once the
-                // window is maximized or fullscreen is enabled.
-                screen->windowed_window_size = get_window_size(screen->window);
-            }
             screen_render(screen);
             break;
         case SDL_WINDOWEVENT_MAXIMIZED:
-            // The backup size must be non-nul.
+            LOGI("MAXIMIZED");
-            assert(screen->windowed_window_size_backup.width);
-            assert(screen->windowed_window_size_backup.height);
-            // Revert the last size, it was updated while screen was maximized.
-            screen->windowed_window_size = screen->windowed_window_size_backup;
-#ifdef DEBUG
-            // Reset the backup to invalid values to detect unexpected usage
-            screen->windowed_window_size_backup.width = 0;
-            screen->windowed_window_size_backup.height = 0;
-#endif
             screen->maximized = true;
             break;
         case SDL_WINDOWEVENT_RESTORED:
+            LOGI("RESTORED");
+            if (screen->fullscreen) {
+                // On Windows, in maximized+fullscreen, disabling fullscreen
+                // mode unexpectedly triggers the "restored" then "maximized"
+                // events, leaving the window in a weird state (maximized
+                // according to the events, but not maximized visually).
+                break;
+            }
             screen->maximized = false;
-            apply_windowed_size(screen);
+            apply_pending_resize(screen);
             break;
     }
 }

app/src/screen.h

@@ -21,11 +21,12 @@ struct screen {
     struct sc_opengl gl;
     struct size frame_size;
     struct size content_size; // rotated frame_size
-    // The window size the last time it was not maximized or fullscreen.
+
-    struct size windowed_window_size;
+    bool resize_pending; // resize requested while fullscreen or maximized
-    // Since we receive the event SIZE_CHANGED before MAXIMIZED, we must be
+    // The content size the last time the window was not maximized or
-    // able to revert the size to its non-maximized value.
+    // fullscreen (meaningful only when resize_pending is true)
-    struct size windowed_window_size_backup;
+    struct size windowed_content_size;
+
     // client rotation: 0, 1, 2 or 3 (x90 degrees counterclockwise)
     unsigned rotation;
     bool has_frame;
@@ -49,11 +50,8 @@ struct screen {
         .width = 0, \
         .height = 0, \
     }, \
-    .windowed_window_size = { \
+    .resize_pending = false, \
-        .width = 0, \
+    .windowed_content_size = { \
-        .height = 0, \
-    }, \
-    .windowed_window_size_backup = { \
         .width = 0, \
         .height = 0, \
     }, \