Different exit codes for failure to connect and disconnect

Modify the return logic such that exit code 1 is used when the initial
connection fails, but if a session is established, and then the device
disconnects, exit code 2 is emitted.

Closes: Github:Genymobile/scrcpy#3083
Signed-off-by: martin f. krafft <madduck@madduck.net>

app/scrcpy.1

@@ -355,6 +355,12 @@ Set the initial window height.
 
 Default is 0 (automatic).
 
+.SH EXIT CODES
+.B scrcpy
+will exit with code 0 on normal program termination. If an initial
+connection cannot be established, the exit code 1 will be returned. If the
+device disconnects while a session is active, exit code 2 will be returned.
+
 .SH SHORTCUTS
 
 In the following list, MOD is the shortcut modifier. By default, it's (left)

app/src/main.c

@@ -70,13 +70,13 @@ main(int argc, char *argv[]) {
     }
 
 #ifdef HAVE_USB
-    bool ok = args.opts.otg ? scrcpy_otg(&args.opts)
+    int ret = args.opts.otg ? scrcpy_otg(&args.opts)
                             : scrcpy(&args.opts);
 #else
-    bool ok = scrcpy(&args.opts);
+    int ret = scrcpy(&args.opts);
 #endif
 
     avformat_network_deinit(); // ignore failure
 
-    return ok ? 0 : 1;
+    return ret;
 }

app/src/scrcpy.c

@@ -149,17 +149,17 @@ sdl_configure(bool display, bool disable_screensaver) {
     }
 }
 
-static bool
+static int
 event_loop(struct scrcpy *s) {
     SDL_Event event;
     while (SDL_WaitEvent(&event)) {
         switch (event.type) {
             case EVENT_STREAM_STOPPED:
                 LOGW("Device disconnected");
-                return false;
+                return EVENT_STREAM_STOPPED;
             case SDL_QUIT:
                 LOGD("User requested to quit");
-                return true;
+                return SDL_QUIT;
             default:
                 sc_screen_handle_event(&s->screen, &event);
                 break;
@@ -168,20 +168,20 @@ event_loop(struct scrcpy *s) {
     return false;
 }
 
-static bool
+static int
 await_for_server(void) {
     SDL_Event event;
     while (SDL_WaitEvent(&event)) {
         switch (event.type) {
             case SDL_QUIT:
                 LOGD("User requested to quit");
-                return false;
+                return SDL_QUIT;
             case EVENT_SERVER_CONNECTION_FAILED:
                 LOGE("Server connection failed");
-                return false;
+                return EVENT_SERVER_CONNECTION_FAILED;
             case EVENT_SERVER_CONNECTED:
                 LOGD("Server connected");
-                return true;
+                return 0;
             default:
                 break;
         }
@@ -262,7 +262,7 @@ sc_server_on_disconnected(struct sc_server *server, void *userdata) {
     // event
 }
 
-bool
+int
 scrcpy(struct scrcpy_options *options) {
     static struct scrcpy scrcpy;
     struct scrcpy *s = &scrcpy;
@@ -275,7 +275,7 @@ scrcpy(struct scrcpy_options *options) {
 
     atexit(SDL_Quit);
 
-    bool ret = false;
+    int ret = 0;
 
     bool server_started = false;
     bool file_pusher_initialized = false;
@@ -351,7 +351,8 @@ scrcpy(struct scrcpy_options *options) {
     sdl_configure(options->display, options->disable_screensaver);
 
     // Await for server without blocking Ctrl+C handling
-    if (!await_for_server()) {
+    ret = await_for_server();
+    if (ret > 0) {
         goto end;
     }
 
@@ -707,5 +708,14 @@ end:
 
     sc_server_destroy(&s->server);
 
-    return ret;
+    switch (ret) {
+      case EVENT_STREAM_STOPPED:
+        return 2;
+      case EVENT_SERVER_CONNECTION_FAILED:
+        return 1;
+      case SDL_QUIT:
+        return 0;
+      default:
+        return ret;
+    }
 }

app/src/scrcpy.h

@@ -6,7 +6,7 @@
 #include <stdbool.h>
 #include "options.h"
 
-bool
+int
 scrcpy(struct scrcpy_options *options);
 
 #endif

app/src/usb/scrcpy_otg.c

@@ -36,10 +36,10 @@ event_loop(struct scrcpy_otg *s) {
         switch (event.type) {
             case EVENT_USB_DEVICE_DISCONNECTED:
                 LOGW("Device disconnected");
-                return false;
+                return EVENT_USB_DEVICE_DISCONNECTED;
             case SDL_QUIT:
                 LOGD("User requested to quit");
-                return true;
+                return SDL_QUIT;
             default:
                 sc_screen_otg_handle_event(&s->screen_otg, &event);
                 break;
@@ -67,7 +67,7 @@ scrcpy_otg(struct scrcpy_options *options) {
         LOGW("Could not enable mouse focus clickthrough");
     }
 
-    bool ret = false;
+    int ret = 0;
 
     struct sc_hid_keyboard *keyboard = NULL;
     struct sc_hid_mouse *mouse = NULL;