Add --no-kill-adb-before-otg option

Add an option not to kill the adb daemon on Windows if --otg is
specified.

Refs #4028 <https://github.com/Genymobile/scrcpy/issues/4028>
PR #4035 <https://github.com/Genymobile/scrcpy/pull/4035>

Signed-off-by: Romain Vimont <rom@rom1v.com>

app/src/cli.c

@@ -77,6 +77,7 @@ enum {
     OPT_NO_AUDIO_PLAYBACK,
     OPT_NO_VIDEO_PLAYBACK,
     OPT_AUDIO_SOURCE,
+    OPT_NO_KILL_ADB_BEFORE_OTG,
 };
 
 struct sc_option {
@@ -411,6 +412,16 @@ static const struct sc_option options[] = {
         .longopt = "no-key-repeat",
         .text = "Do not forward repeated key events when a key is held down.",
     },
+    {
+        .longopt_id = OPT_NO_KILL_ADB_BEFORE_OTG,
+        .longopt = "no-kill-adb-before-otg",
+        // with .text, the option is not documented on other platforms
+#ifdef _WIN32
+        .text = "By default, scrcpy kills the adb daemon on Windows if --otg "
+                "is specified.\n"
+                "This option avoids to kill the adb daemon.",
+#endif
+    },
     {
         .longopt_id = OPT_NO_MIPMAPS,
         .longopt = "no-mipmaps",
@@ -1944,6 +1955,14 @@ parse_args_with_getopt(struct scrcpy_cli_args *args, int argc, char *argv[],
                     return false;
                 }
                 break;
+            case OPT_NO_KILL_ADB_BEFORE_OTG:
+#ifdef _WIN32
+                opts->kill_adb_before_otg = false;
+                break;
+#else
+                LOGE("--no-kill-adb-before-otg only exists on Windows.");
+                return false;
+#endif
             default:
                 // getopt prints the error message on stderr
                 return false;

app/src/options.c

@@ -48,6 +48,9 @@ const struct scrcpy_options scrcpy_options_default = {
 #endif
 #ifdef HAVE_USB
     .otg = false,
+#endif
+#ifdef _WIN32
+    .kill_adb_before_otg = true,
 #endif
     .show_touches = false,
     .fullscreen = false,

app/src/options.h

@@ -148,6 +148,9 @@ struct scrcpy_options {
 #endif
 #ifdef HAVE_USB
     bool otg;
+#endif
+#ifdef _WIN32
+    bool kill_adb_before_otg;
 #endif
     bool show_touches;
     bool fullscreen;

app/src/usb/scrcpy_otg.c

@@ -83,10 +83,12 @@ scrcpy_otg(struct scrcpy_options *options) {
 #ifdef _WIN32
     // On Windows, only one process could open a USB device
     // <https://github.com/Genymobile/scrcpy/issues/2773>
-    LOGI("Killing adb daemon (if any)...");
-    unsigned flags = SC_ADB_NO_STDOUT | SC_ADB_NO_STDERR | SC_ADB_NO_LOGERR;
-    // uninterruptible (intr == NULL), but in practice it's very quick
-    sc_adb_kill_server(NULL, flags);
+    if (options->kill_adb_before_otg) {
+        LOGI("Killing adb daemon (if any)...");
+        unsigned flags = SC_ADB_NO_STDOUT | SC_ADB_NO_STDERR | SC_ADB_NO_LOGERR;
+        // uninterruptible (intr == NULL), but in practice it's very quick
+        sc_adb_kill_server(NULL, flags);
+    }
 #endif
 
     static const struct sc_usb_callbacks cbs = {