Cygwin: try a horrible hack to fix integration test with unix sockets

test/integration/CMakeLists.txt

@@ -56,3 +56,10 @@ target_include_directories(inttest PUBLIC
 	"${GMOCK_ROOT}" "${GMOCK_ROOT}/include")
 target_compile_definitions(inttest PRIVATE
 	"ZNC_BIN_DIR=\"${ZNC_BIN_DIR}\"")
+
+if(CYGWIN)
+	# This workaround contains a sizeable modified copypaste of Qt's qlocalsocket_unix.cpp, which is LGPL, so has to be in a separate shared library.
+	add_library(inttest_cygwin SHARED framework/cygwin.cpp)
+	target_link_libraries(inttest_cygwin Qt${ZNC_QT_VER}::NetworkPrivate)
+	target_link_libraries(inttest inttest_cygwin)
+endif()

test/integration/framework/cygwin.cpp

@@ -0,0 +1,99 @@
+// This file is LGPL, as it's based on Qt's qlocalsocket_unix.cpp
+// The original header follows:
+
+/****************************************************************************
+**
+** Copyright (C) 2016 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtNetwork module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "cygwin.h"
+
+#include <QFile>
+#include <QtNetwork/private/qlocalsocket_p.h>
+#include <QtNetwork/private/qnet_unix_p.h>
+#include <sys/un.h>
+
+namespace znc_inttest_cygwin {
+// https://stackoverflow.com/questions/424104/can-i-access-private-members-from-outside-the-class-without-using-friends
+template <typename Tag, typename Tag::type M>
+struct Rob {
+    friend typename Tag::type get(Tag) { return M; }
+};
+struct A_member {
+    using type = QScopedPointer<QObjectData> QObject::*;
+    friend type get(A_member);
+};
+template struct Rob<A_member, &QObject::d_ptr>;
+
+// This function is inspired by QLocalSocket::connectToServer() and QLocalSocketPrivate::_q_connectToSocket()
+void CygwinWorkaroundLocalConnect(QLocalSocket& sock) {
+    QObjectData* o = (sock.*get(A_member())).get();
+    QLocalSocketPrivate* d = reinterpret_cast<QLocalSocketPrivate*>(o);
+    d->unixSocket.setSocketState(QAbstractSocket::ConnectingState);
+    d->state = QLocalSocket::ConnectingState;
+    sock.stateChanged(d->state);
+
+    if ((d->connectingSocket = qt_safe_socket(PF_UNIX, SOCK_STREAM, 0, 0)) ==
+        -1) {
+        sock.errorOccurred(QLocalSocket::UnsupportedSocketOperationError);
+        return;
+    }
+
+    d->fullServerName = d->serverName;
+
+    const QByteArray encodedConnectingPathName =
+        QFile::encodeName(d->serverName);
+    struct sockaddr_un name;
+    name.sun_family = PF_UNIX;
+    ::memcpy(name.sun_path, encodedConnectingPathName.constData(),
+             encodedConnectingPathName.size() + 1);
+    if (qt_safe_connect(d->connectingSocket, (struct sockaddr*)&name,
+                        sizeof(name)) == -1) {
+        sock.errorOccurred(QLocalSocket::UnknownSocketError);
+        return;
+    }
+
+    ::fcntl(d->connectingSocket, F_SETFL,
+            ::fcntl(d->connectingSocket, F_GETFL) | O_NONBLOCK);
+    d->unixSocket.setSocketDescriptor(d->connectingSocket,
+                                      QAbstractSocket::ConnectedState);
+    sock.QIODevice::open(QLocalSocket::ReadWrite | QLocalSocket::Unbuffered);
+    sock.connected();
+    d->connectingSocket = -1;
+    d->connectingName.clear();
+}
+}  // namespace znc_inttest_cygwin

test/integration/framework/cygwin.h

@@ -0,0 +1,11 @@
+#pragma once
+
+#include <QLocalSocket>
+
+namespace znc_inttest_cygwin {
+// Qt uses non-blocking sockets for unix sockets, but cygwin emulates them via
+// AF_INET sockets, so connect() fails. This function connects the socket by
+// reaching into private parts of QLocalSocket, and sets it non-blocking only
+// after connect().
+void CygwinWorkaroundLocalConnect(QLocalSocket& sock);
+}

test/integration/framework/znctest.cpp

@@ -17,6 +17,7 @@
 #include <QRegularExpression>
 #include <QProcess>
 #include "znctest.h"
+#include "cygwin.h"
 
 #ifndef ZNC_BIN_DIR
 #define ZNC_BIN_DIR ""
@@ -76,7 +77,12 @@ Socket ZNCTest::ConnectIRCd() {
 Socket ZNCTest::ConnectClient() {
     m_clients.emplace_back();
     QLocalSocket& sock = m_clients.back();
-    sock.connectToServer(m_dir.path() + "/inttest.znc");
+    sock.setServerName(m_dir.path() + "/inttest.znc");
+#ifdef __CYGWIN__
+    znc_inttest_cygwin::CygwinWorkaroundLocalConnect(sock);
+#else
+    sock.connectToServer();
+#endif
     [&] {
         ASSERT_TRUE(sock.waitForConnected())
             << sock.errorString().toStdString();

test/integration/tests/modules.cpp

@@ -242,6 +242,8 @@ TEST_F(ZNCTest, KeepNickModule) {
 }
 
 TEST_F(ZNCTest, ModuleCSRFOverride) {
+    // TODO: Qt 6.8 introduced QNetworkRequest::FullLocalServerNameAttribute to
+    // let it connect to unix socket
     int port = PickPortNumber();
     auto znc = Run();
     auto ircd = ConnectIRCd();