Expose function to test if a serial is TCP/IP

In practice, it just tests if the serial contains a ':', which is
sufficient to distinguish ip:port from a real USB serial.

PR #3005 <https://github.com/Genymobile/scrcpy/pull/3005>

app/src/adb/adb.c

@@ -482,3 +482,8 @@ sc_adb_get_device_ip(struct sc_intr *intr, const char *serial, unsigned flags) {
 
     return sc_adb_parse_device_ip_from_output(buf);
 }
+
+bool
+sc_adb_is_serial_tcpip(const char *serial) {
+    return strchr(serial, ':');
+}

app/src/adb/adb.h

@@ -93,4 +93,13 @@ sc_adb_get_serialno(struct sc_intr *intr, unsigned flags);
 char *
 sc_adb_get_device_ip(struct sc_intr *intr, const char *serial, unsigned flags);
 
+/**
+ * Indicate if the serial represents an IP address
+ *
+ * In practice, it just returns true if and only if it contains a ':', which is
+ * sufficient to distinguish an ip:port from a real USB serial.
+ */
+bool
+sc_adb_is_serial_tcpip(const char *serial);
+
 #endif

app/src/server.c

@@ -659,10 +659,7 @@ sc_server_configure_tcpip_known_address(struct sc_server *server,
 static bool
 sc_server_configure_tcpip_unknown_address(struct sc_server *server,
                                           const char *serial) {
-    // The serial is either the real serial when connected via USB, or
+    bool is_already_tcpip = sc_adb_is_serial_tcpip(serial);
-    // the IP:PORT when connected over TCP/IP. Only the latter contains
-    // a colon.
-    bool is_already_tcpip = strchr(serial, ':');
     if (is_already_tcpip) {
         // Nothing to do
         LOGI("Device already connected via TCP/IP: %s", serial);