Add --tcpip feature

Expose an option to automatically configure and reconnect the device
over TCP/IP, to simplify wireless connection without using adb
explicitly.

There are two variants:
 - If a destination address is provided, then scrcpy connects to this
   address before starting. The device must listen on the given TCP port
   (default is 5555).
 - If no destination address is provided, then scrcpy attempts to find
   the IP address of the current device (typically connected over USB),
   enables TCP/IP mode, then connects to this address before starting.

app/scrcpy.1

@@ -199,6 +199,14 @@ For example, to use either LCtrl+LAlt or LSuper for scrcpy shortcuts, pass "lctr
 
 Default is "lalt,lsuper" (left-Alt or left-Super).
 
+.TP
+.BI "\-\-tcpip[=ip[:port]]
+Configure and reconnect the device over TCP/IP.
+
+If a destination address is provided, then scrcpy connects to this address before starting. The device must listen on the given TCP port (default is 5555).
+
+If no destination address is provided, then scrcpy attempts to find the IP address of the current device (typically connected over USB), enables TCP/IP mode, then connects to this address before starting.
+
 .TP
 .B \-S, \-\-turn\-screen\-off
 Turn the device screen off immediately.

app/src/adb.h

@@ -12,6 +12,8 @@
 #define SC_ADB_NO_STDERR (1 << 1)
 #define SC_ADB_NO_LOGERR (1 << 2)
 
+#define SC_ADB_SILENT (SC_ADB_NO_STDOUT | SC_ADB_NO_STDERR | SC_ADB_NO_LOGERR)
+
 sc_pid
 adb_execute(const char *serial, const char *const adb_cmd[], size_t len,
             unsigned flags);

app/src/cli.c

@@ -50,6 +50,7 @@
 #define OPT_TUNNEL_HOST            1030
 #define OPT_TUNNEL_PORT            1031
 #define OPT_NO_CLIPBOARD_AUTOSYNC  1032
+#define OPT_TCPIP                  1033
 
 struct sc_option {
     char shortopt;
@@ -404,6 +405,20 @@ static const struct sc_option options[] = {
         .text = "Keep the device on while scrcpy is running, when the device "
                 "is plugged in.",
     },
+    {
+        .longopt_id = OPT_TCPIP,
+        .longopt = "tcpip",
+        .argdesc = "ip[:port]",
+        .optional_arg = true,
+        .text = "Configure and reconnect the device over TCP/IP.\n"
+                "If a destination address is provided, then scrcpy connects to "
+                "this address before starting. The device must listen on the "
+                "given TCP port (default is 5555).\n"
+                "If no destination address is provided, then scrcpy attempts "
+                "to find the IP address of the current device (typically "
+                "connected over USB), enables TCP/IP mode, then connects to "
+                "this address before starting.\n",
+    },
     {
         .longopt_id = OPT_WINDOW_BORDERLESS,
         .longopt = "window-borderless",
@@ -1378,6 +1393,10 @@ parse_args_with_getopt(struct scrcpy_cli_args *args, int argc, char *argv[],
             case OPT_NO_CLIPBOARD_AUTOSYNC:
                 opts->clipboard_autosync = false;
                 break;
+            case OPT_TCPIP:
+                opts->tcpip = true;
+                opts->tcpip_dst = optarg;
+                break;
 #ifdef HAVE_V4L2
             case OPT_V4L2_SINK:
                 opts->v4l2_device = optarg;
@@ -1400,6 +1419,14 @@ parse_args_with_getopt(struct scrcpy_cli_args *args, int argc, char *argv[],
         return false;
     }
 
+    // If a TCP/IP address is provided, then tcpip must be enabled
+    assert(opts->tcpip || !opts->tcpip_dst);
+
+    if (opts->serial && opts->tcpip_dst) {
+        LOGE("Incompatible options: -s/--serial and --tcpip with an argument");
+        return false;
+    }
+
 #ifdef HAVE_V4L2
     if (!opts->display && !opts->record_filename && !opts->v4l2_device) {
         LOGE("-N/--no-display requires either screen recording (-r/--record)"

app/src/options.c

@@ -54,4 +54,6 @@ const struct scrcpy_options scrcpy_options_default = {
     .legacy_paste = false,
     .power_off_on_close = false,
     .clipboard_autosync = true,
+    .tcpip = false,
+    .tcpip_dst = NULL,
 };

app/src/options.h

@@ -109,6 +109,8 @@ struct scrcpy_options {
     bool legacy_paste;
     bool power_off_on_close;
     bool clipboard_autosync;
+    bool tcpip;
+    const char *tcpip_dst;
 };
 
 extern const struct scrcpy_options scrcpy_options_default;

app/src/scrcpy.c

@@ -365,6 +365,8 @@ scrcpy(struct scrcpy_options *options) {
         .force_adb_forward = options->force_adb_forward,
         .power_off_on_close = options->power_off_on_close,
         .clipboard_autosync = options->clipboard_autosync,
+        .tcpip = options->tcpip,
+        .tcpip_dst = options->tcpip_dst,
     };
 
     static const struct sc_server_callbacks cbs = {

app/src/server.c

@@ -69,6 +69,7 @@ sc_server_params_destroy(struct sc_server_params *params) {
     free((char *) params->crop);
     free((char *) params->codec_options);
     free((char *) params->encoder_name);
+    free((char *) params->tcpip_dst);
 }
 
 static bool
@@ -92,6 +93,7 @@ sc_server_params_copy(struct sc_server_params *dst,
     COPY(crop);
     COPY(codec_options);
     COPY(encoder_name);
+    COPY(tcpip_dst);
 #undef COPY
 
     return true;
@@ -494,22 +496,216 @@ sc_server_fill_serial(struct sc_server *server) {
             LOGE("Could not get device serial");
             return false;
         }
+
+        LOGD("Device serial: %s", server->params.serial);
+    }
+
+    return true;
+}
+
+static bool
+is_tcpip_mode_enabled(struct sc_server *server) {
+    struct sc_intr *intr = &server->intr;
+    const char *serial = server->params.serial;
+
+    char *current_port =
+        adb_getprop(intr, serial, "service.adb.tcp.port", SC_ADB_SILENT);
+    if (!current_port) {
+        return false;
+    }
+
+    // Is the device is listening on TCP on port 5555
+    bool enabled = !strcmp("5555", current_port);
+    free(current_port);
+    return enabled;
+}
+
+static bool
+wait_tcpip_mode_enabled(struct sc_server *server, unsigned attempts,
+                        sc_tick delay) {
+    if (is_tcpip_mode_enabled(server)) {
+        LOGI("TCP/IP mode enabled");
+        return true;
+    }
+
+    // Only print this log if TCP/IP is not enabled
+    LOGI("Waiting for TCP/IP mode enabled...");
+
+    do {
+        sc_tick deadline = sc_tick_now() + delay;
+        if (!sc_server_sleep(server, deadline)) {
+            LOGI("TCP/IP mode waiting interrupted");
+            return false;
+        }
+
+        if (is_tcpip_mode_enabled(server)) {
+            LOGI("TCP/IP mode enabled");
+            return true;
+        }
+    } while (--attempts);
+    return false;
+}
+
+char *
+append_port_5555(const char *ip) {
+    size_t len = strlen(ip);
+
+    // sizeof counts the final '\0'
+    char *ip_port = malloc(len + sizeof(":5555"));
+    if (!ip_port) {
+        LOG_OOM();
+        return NULL;
+    }
+
+    memcpy(ip_port, ip, len);
+    memcpy(ip_port + len, ":5555", sizeof(":5555"));
+
+    return ip_port;
+}
+
+static bool
+sc_server_switch_to_tcpip(struct sc_server *server, char **out_ip_port) {
+    const char *serial = server->params.serial;
+    assert(serial);
+
+    struct sc_intr *intr = &server->intr;
+
+    char *ip = adb_get_device_ip(intr, serial, 0);
+    if (!ip) {
+        LOGE("Device IP not found");
+        return false;
+    }
+
+    char *ip_port = append_port_5555(ip);
+    free(ip);
+    if (!ip_port) {
+        return false;
+    }
+
+    bool tcp_mode = is_tcpip_mode_enabled(server);
+
+    if (!tcp_mode) {
+        bool ok = adb_tcpip(intr, serial, 5555, SC_ADB_NO_STDOUT);
+        if (!ok) {
+            LOGE("Could not restart adbd in TCP/IP mode");
+            goto error;
+        }
+
+        unsigned attempts = 40;
+        sc_tick delay = SC_TICK_FROM_MS(250);
+        ok = wait_tcpip_mode_enabled(server, attempts, delay);
+        if (!ok) {
+            goto error;
+        }
+    }
+
+    *out_ip_port = ip_port;
+
+    return true;
+
+error:
+    free(ip_port);
+    return false;
+}
+
+static bool
+sc_server_connect_to_tcpip(struct sc_server *server, const char *ip_port) {
+    struct sc_intr *intr = &server->intr;
+
+    // Error expected if not connected, do not report any error
+    adb_disconnect(intr, ip_port, SC_ADB_SILENT);
+
+    bool ok = adb_connect(intr, ip_port, 0);
+    if (!ok) {
+        LOGE("Could not connect to %s", ip_port);
+        return false;
     }
 
+    // Override the serial, owned by the sc_server_params
+    free((void *) server->params.serial);
+    server->params.serial = strdup(ip_port);
+    if (!server->params.serial) {
+        LOG_OOM();
+        return false;
+    }
+
+    LOGI("Connected to %s", ip_port);
     return true;
 }
 
+
+static bool
+sc_server_configure_tcpip(struct sc_server *server) {
+    char *ip_port;
+
+    const struct sc_server_params *params = &server->params;
+
+    // If tcpip parameter is given, then it must connect to this address.
+    // Therefore, the device is unknown, so serial is meaningless at this point.
+    assert(!params->serial || !params->tcpip_dst);
+
+    if (params->tcpip_dst) {
+        // Append ":5555" if no port is present
+        bool contains_port = strchr(params->tcpip_dst, ':');
+        ip_port = contains_port ? strdup(params->tcpip_dst)
+                                : append_port_5555(params->tcpip_dst);
+        if (!ip_port) {
+            LOG_OOM();
+            return false;
+        }
+    } else {
+        // The device IP address must be retrieved from the current
+        // connected device
+        if (!sc_server_fill_serial(server)) {
+            return false;
+        }
+
+        // The serial is either the real serial when connected via USB, or
+        // the IP:PORT when connected over TCP/IP. Only the latter contains
+        // a colon.
+        bool is_already_tcpip = strchr(params->serial, ':');
+        if (is_already_tcpip) {
+            // Nothing to do
+            LOGI("Device is already connected via TCP/IP: %s",
+                 params->serial);
+            return true;
+        }
+
+        bool ok = sc_server_switch_to_tcpip(server, &ip_port);
+        if (!ok) {
+            return false;
+        }
+    }
+
+    // On success, this call changes params->serial
+    bool ok = sc_server_connect_to_tcpip(server, ip_port);
+    free(ip_port);
+    return ok;
+}
+
 static int
 run_server(void *data) {
     struct sc_server *server = data;
 
-    if (!sc_server_fill_serial(server)) {
-        goto error_connection_failed;
+    const struct sc_server_params *params = &server->params;
+
+    if (params->serial) {
+        LOGD("Device serial: %s", params->serial);
     }
 
-    const struct sc_server_params *params = &server->params;
+    if (params->tcpip) {
+        // params->serial may be changed after this call
+        bool ok = sc_server_configure_tcpip(server);
+        if (!ok) {
+            goto error_connection_failed;
+        }
+    }
 
-    LOGD("Device serial: %s", params->serial);
+    // It is ok to call this function even if the device serial has been
+    // changed to switch over TCP/IP
+    if (!sc_server_fill_serial(server)) {
+        goto error_connection_failed;
+    }
 
     bool ok = push_server(&server->intr, params->serial);
     if (!ok) {

app/src/server.h

@@ -42,6 +42,8 @@ struct sc_server_params {
     bool force_adb_forward;
     bool power_off_on_close;
     bool clipboard_autosync;
+    bool tcpip;
+    const char *tcpip_dst;
 };
 
 struct sc_server {