Provide device info directly on server connection

This avoids to retrieve them in a separate step.

app/meson.build

@@ -6,7 +6,6 @@ src = [
     'src/control_msg.c',
     'src/controller.c',
     'src/decoder.c',
-    'src/device.c',
     'src/device_msg.c',
     'src/event_converter.c',
     'src/file_handler.c',

app/src/scrcpy.c

@@ -15,7 +15,6 @@
 
 #include "controller.h"
 #include "decoder.h"
-#include "device.h"
 #include "events.h"
 #include "file_handler.h"
 #include "input_manager.h"
@@ -284,17 +283,10 @@ scrcpy(const struct scrcpy_options *options) {
         goto end;
     }
 
-    if (!server_connect_to(&server)) {
-        goto end;
-    }
-
     char device_name[DEVICE_NAME_FIELD_LENGTH];
     struct size frame_size;
 
-    // screenrecord does not send frames when the screen content does not
-    // change therefore, we transmit the screen size before the video stream,
-    // to be able to init the window immediately
-    if (!device_read_info(server.video_socket, device_name, &frame_size)) {
+    if (!server_connect_to(&server, device_name, &frame_size)) {
         goto end;
     }
 

app/src/server.c

@@ -464,8 +464,28 @@ server_start(struct server *server, const char *serial,
     return false;
 }
 
+static bool
+device_read_info(socket_t device_socket, char *device_name, struct size *size) {
+    unsigned char buf[DEVICE_NAME_FIELD_LENGTH + 4];
+    int r = net_recv_all(device_socket, buf, sizeof(buf));
+    if (r < DEVICE_NAME_FIELD_LENGTH + 4) {
+        LOGE("Could not retrieve device information");
+        return false;
+    }
+    // in case the client sends garbage
+    buf[DEVICE_NAME_FIELD_LENGTH - 1] = '\0';
+    // strcpy is safe here, since name contains at least
+    // DEVICE_NAME_FIELD_LENGTH bytes and strlen(buf) < DEVICE_NAME_FIELD_LENGTH
+    strcpy(device_name, (char *) buf);
+    size->width = (buf[DEVICE_NAME_FIELD_LENGTH] << 8)
+            | buf[DEVICE_NAME_FIELD_LENGTH + 1];
+    size->height = (buf[DEVICE_NAME_FIELD_LENGTH + 2] << 8)
+            | buf[DEVICE_NAME_FIELD_LENGTH + 3];
+    return true;
+}
+
 bool
-server_connect_to(struct server *server) {
+server_connect_to(struct server *server, char *device_name, struct size *size) {
     if (!server->tunnel_forward) {
         server->video_socket = net_accept(server->server_socket);
         if (server->video_socket == INVALID_SOCKET) {
@@ -505,7 +525,8 @@ server_connect_to(struct server *server) {
     disable_tunnel(server); // ignore failure
     server->tunnel_enabled = false;
 
-    return true;
+    // The sockets will be closed on stop if device_read_info() fails
+    return device_read_info(server->video_socket, device_name, size);
 }
 
 void

app/src/server.h

@@ -8,6 +8,7 @@
 #include <stdint.h>
 
 #include "adb.h"
+#include "coords.h"
 #include "scrcpy.h"
 #include "util/log.h"
 #include "util/net.h"
@@ -58,9 +59,11 @@ bool
 server_start(struct server *server, const char *serial,
              const struct server_params *params);
 
+#define DEVICE_NAME_FIELD_LENGTH 64
 // block until the communication with the server is established
+// device_name must point to a buffer of at least DEVICE_NAME_FIELD_LENGTH bytes
 bool
-server_connect_to(struct server *server);
+server_connect_to(struct server *server, char *device_name, struct size *size);
 
 // disconnect and kill the server process
 void