3 files changed, 35 insertions, 8 deletions

diff --git a/drivers/windows/file_access_windows.cpp b/drivers/windows/file_access_windows.cpp
index e10f4d05e8..aa0fd34e0a 100644
--- a/drivers/windows/file_access_windows.cpp
+++ b/drivers/windows/file_access_windows.cpp
@@ -85,10 +85,31 @@ Error FileAccessWindows::_open(const String &p_path, int p_mode_flags) {
 			return ERR_FILE_CANT_OPEN;
 	};
 
+#ifdef TOOLS_ENABLED
+	// Windows is case insensitive, but all other platforms are sensitive to it
+	// To ease cross-platform development, we issue a warning if users try to access
+	// a file using the wrong case (which *works* on Windows, but won't on other
+	// platforms).
+	if (p_mode_flags == READ) {
+		WIN32_FIND_DATAW d = { 0 };
+		HANDLE f = FindFirstFileW(path.c_str(), &d);
+		if (f) {
+			String fname = d.cFileName;
+			if (fname != String()) {
+
+				String base_file = path.get_file();
+				if (base_file != fname && base_file.findn(fname) == 0) {
+					WARN_PRINTS("Case mismatch opening requested file '" + base_file + "', stored as '" + fname + "' in the filesystem. This file will not open when exported to other case-sensitive platforms.");
+				}
+			}
+			FindClose(f);
+		}
+	}
+#endif
+
 	if (is_backup_save_enabled() && p_mode_flags & WRITE && !(p_mode_flags & READ)) {
 		save_path = path;
 		path = path + ".tmp";
-		//print_line("saving instead to "+path);
 	}
 
 	f = _wfopen(path.c_str(), mode_string);
@@ -113,7 +134,7 @@ void FileAccessWindows::close() {
 	if (save_path != "") {
 
 		//unlink(save_path.utf8().get_data());
-		//print_line("renaming..");
+		//print_line("renaming...");
 		//_wunlink(save_path.c_str()); //unlink if exists
 		//int rename_error = _wrename((save_path+".tmp").c_str(),save_path.c_str());
 
@@ -139,19 +160,22 @@ void FileAccessWindows::close() {
 				//atomic replace for existing file
 				rename_error = !ReplaceFileW(save_path.c_str(), (save_path + ".tmp").c_str(), NULL, 2 | 4, NULL, NULL);
 			}
-			if (rename_error && close_fail_notify) {
-				close_fail_notify(save_path);
-			}
 			if (rename_error) {
 				attempts--;
-				OS::get_singleton()->delay_usec(1000000); //wait 100msec and try again
+				OS::get_singleton()->delay_usec(100000); // wait 100msec and try again
 			}
 		}
 
-		save_path = "";
 		if (rename_error) {
+			if (close_fail_notify) {
+				close_fail_notify(save_path);
+			}
+
 			ERR_EXPLAIN("Safe save failed. This may be a permissions problem, but also may happen because you are running a paranoid antivirus. If this is the case, please switch to Windows Defender or disable the 'safe save' option in editor settings. This makes it work, but increases the risk of file corruption in a crash.");
 		}
+
+		save_path = "";
+
 		ERR_FAIL_COND(rename_error);
 	}
 }
diff --git a/drivers/windows/stream_peer_tcp_winsock.cpp b/drivers/windows/stream_peer_tcp_winsock.cpp
index 55775fc231..cb501ce35d 100644
--- a/drivers/windows/stream_peer_tcp_winsock.cpp
+++ b/drivers/windows/stream_peer_tcp_winsock.cpp
@@ -335,7 +335,9 @@ Error StreamPeerTCPWinsock::connect_to_host(const IP_Address &p_host, uint16_t p
 void StreamPeerTCPWinsock::set_no_delay(bool p_enabled) {
 	ERR_FAIL_COND(!is_connected_to_host());
 	int flag = p_enabled ? 1 : 0;
-	setsockopt(sockfd, IPPROTO_TCP, TCP_NODELAY, (char *)&flag, sizeof(int));
+	if (setsockopt(sockfd, IPPROTO_TCP, TCP_NODELAY, (char *)&flag, sizeof(int)) != 0) {
+		ERR_PRINT("Unable to set TCP no delay option");
+	}
 }
 
 int StreamPeerTCPWinsock::get_available_bytes() const {
diff --git a/drivers/windows/tcp_server_winsock.cpp b/drivers/windows/tcp_server_winsock.cpp
index 413a0d19b5..ddb955549f 100644
--- a/drivers/windows/tcp_server_winsock.cpp
+++ b/drivers/windows/tcp_server_winsock.cpp
@@ -105,6 +105,7 @@ Error TCPServerWinsock::listen(uint16_t p_port, const IP_Address &p_bind_address
 			ERR_FAIL_V(FAILED);
 		};
 	} else {
+		closesocket(sockfd);
 		return ERR_ALREADY_IN_USE;
 	};