Move frame updating to screen.c

Replace screen_update() by a higher-level screen_update_frame() handling
the whole frame updating, so that scrcpy.c just call it without managing
implementation details.

app/src/scrcpy.c

@@ -46,19 +46,6 @@ static void count_frame(void) {
     }
 }
 
-static SDL_bool handle_new_frame(void) {
-    mutex_lock(frames.mutex);
-    const AVFrame *frame = frames_consume_rendered_frame(&frames);
-    if (!screen_update(&screen, frame)){
-        mutex_unlock(frames.mutex);
-        return SDL_FALSE;
-    }
-    mutex_unlock(frames.mutex);
-
-    screen_render(&screen);
-    return SDL_TRUE;
-}
-
 static void event_loop(void) {
     SDL_Event event;
     while (SDL_WaitEvent(&event)) {
@@ -70,7 +57,7 @@ static void event_loop(void) {
                 SDL_LogDebug(SDL_LOG_CATEGORY_APPLICATION, "User requested to quit");
                 return;
             case EVENT_NEW_FRAME:
-                if (!handle_new_frame()) {
+                if (!screen_update_frame(&screen, &frames)) {
                     return;
                 }
                 count_frame(); // display fps for debug

app/src/screen.c

@@ -4,6 +4,7 @@
 #include <string.h>
 
 #include "icon.xpm"
+#include "lockutil.h"
 #include "tinyxpm.h"
 
 #define DISPLAY_MARGINS 96
@@ -237,12 +238,18 @@ static void update_texture(struct screen *screen, const AVFrame *frame) {
             frame->data[2], frame->linesize[2]);
 }
 
-SDL_bool screen_update(struct screen *screen, const AVFrame *frame) {
+SDL_bool screen_update_frame(struct screen *screen, struct frames *frames) {
+    mutex_lock(frames->mutex);
+    const AVFrame *frame = frames_consume_rendered_frame(frames);
     struct size new_frame_size = {frame->width, frame->height};
     if (!prepare_for_frame(screen, new_frame_size)) {
+        mutex_unlock(frames->mutex);
         return SDL_FALSE;
     }
     update_texture(screen, frame);
+    mutex_unlock(frames->mutex);
+
+    screen_render(screen);
     return SDL_TRUE;
 }
 

app/src/screen.h

@@ -5,6 +5,7 @@
 #include <libavformat/avformat.h>
 
 #include "common.h"
+#include "frames.h"
 
 struct screen {
     SDL_Window *window;
@@ -47,8 +48,8 @@ SDL_bool screen_init_rendering(struct screen *screen,
 // destroy window, renderer and texture (if any)
 void screen_destroy(struct screen *screen);
 
-// resize if necessary and write the frame into the texture
-SDL_bool screen_update(struct screen *screen, const AVFrame *frame);
+// resize if necessary and write the rendered frame into the texture
+SDL_bool screen_update_frame(struct screen *screen, struct frames *frames);
 
 // render the texture to the renderer
 void screen_render(struct screen *screen);