From 676fa73d2c19d4828921640588e42d1911ad2147 Mon Sep 17 00:00:00 2001
From: Romain Vimont <rom@rom1v.com>
Date: Sat, 30 Oct 2021 19:07:35 +0200
Subject: [PATCH] Wrap device name and size in a struct

As a benefit, this avoids to take care of the device name length on the
caller side.
---
 app/src/scrcpy.c | 15 +++++++--------
 app/src/server.c | 21 +++++++++------------
 app/src/server.h | 11 +++++++----
 3 files changed, 23 insertions(+), 24 deletions(-)

diff --git a/app/src/scrcpy.c b/app/src/scrcpy.c
index c7033a26..c8adb5a1 100644
--- a/app/src/scrcpy.c
+++ b/app/src/scrcpy.c
@@ -331,10 +331,9 @@ scrcpy(struct scrcpy_options *options) {
 
     sdl_configure(options->display, options->disable_screensaver);
 
-    char device_name[DEVICE_NAME_FIELD_LENGTH];
-    struct sc_size frame_size;
+    struct server_info info;
 
-    if (!server_connect_to(&s->server, device_name, &frame_size)) {
+    if (!server_connect_to(&s->server, &info)) {
         goto end;
     }
 
@@ -361,7 +360,7 @@ scrcpy(struct scrcpy_options *options) {
         if (!recorder_init(&s->recorder,
                            options->record_filename,
                            options->record_format,
-                           frame_size)) {
+                           info.frame_size)) {
             goto end;
         }
         rec = &s->recorder;
@@ -407,11 +406,11 @@ scrcpy(struct scrcpy_options *options) {
 
     if (options->display) {
         const char *window_title =
-            options->window_title ? options->window_title : device_name;
+            options->window_title ? options->window_title : info.device_name;
 
         struct screen_params screen_params = {
             .window_title = window_title,
-            .frame_size = frame_size,
+            .frame_size = info.frame_size,
             .always_on_top = options->always_on_top,
             .window_x = options->window_x,
             .window_y = options->window_y,
@@ -434,8 +433,8 @@ scrcpy(struct scrcpy_options *options) {
 
 #ifdef HAVE_V4L2
     if (options->v4l2_device) {
-        if (!sc_v4l2_sink_init(&s->v4l2_sink, options->v4l2_device, frame_size,
-                               options->v4l2_buffer)) {
+        if (!sc_v4l2_sink_init(&s->v4l2_sink, options->v4l2_device,
+                               info.frame_size, options->v4l2_buffer)) {
             goto end;
         }
 
diff --git a/app/src/server.c b/app/src/server.c
index 50d7f836..4a4d3ec4 100644
--- a/app/src/server.c
+++ b/app/src/server.c
@@ -426,8 +426,7 @@ error:
 }
 
 static bool
-device_read_info(sc_socket device_socket, char *device_name,
-                 struct sc_size *size) {
+device_read_info(sc_socket device_socket, struct server_info *info) {
     unsigned char buf[DEVICE_NAME_FIELD_LENGTH + 4];
     ssize_t r = net_recv_all(device_socket, buf, sizeof(buf));
     if (r < DEVICE_NAME_FIELD_LENGTH + 4) {
@@ -436,19 +435,17 @@ device_read_info(sc_socket device_socket, char *device_name,
     }
     // 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];
+    memcpy(info->device_name, (char *) buf, sizeof(info->device_name));
+
+    info->frame_size.width = (buf[DEVICE_NAME_FIELD_LENGTH] << 8)
+                           | buf[DEVICE_NAME_FIELD_LENGTH + 1];
+    info->frame_size.height = (buf[DEVICE_NAME_FIELD_LENGTH + 2] << 8)
+                            | buf[DEVICE_NAME_FIELD_LENGTH + 3];
     return true;
 }
 
 bool
-server_connect_to(struct server *server, char *device_name,
-                  struct sc_size *size) {
+server_connect_to(struct server *server, struct server_info *info) {
     if (!server->tunnel_forward) {
         server->video_socket = net_accept(server->server_socket);
         if (server->video_socket == SC_INVALID_SOCKET) {
@@ -489,7 +486,7 @@ server_connect_to(struct server *server, char *device_name,
     server->tunnel_enabled = false;
 
     // The sockets will be closed on stop if device_read_info() fails
-    return device_read_info(server->video_socket, device_name, size);
+    return device_read_info(server->video_socket, info);
 }
 
 void
diff --git a/app/src/server.h b/app/src/server.h
index b291c0a5..242b0525 100644
--- a/app/src/server.h
+++ b/app/src/server.h
@@ -14,6 +14,12 @@
 #include "util/net.h"
 #include "util/thread.h"
 
+#define DEVICE_NAME_FIELD_LENGTH 64
+struct server_info {
+    char device_name[DEVICE_NAME_FIELD_LENGTH];
+    struct sc_size frame_size;
+};
+
 struct server {
     char *serial;
     process_t process;
@@ -58,12 +64,9 @@ server_init(struct server *server);
 bool
 server_start(struct server *server, 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, char *device_name,
-                  struct sc_size *size);
+server_connect_to(struct server *server, struct server_info *info);
 
 // disconnect and kill the server process
 void