feat: add an own lock screen with the bubble and your wallpaper

tests/test_lockscreen.cpp

@@ -0,0 +1,85 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+//
+// The password on face-unlock's own lock screen, through real PAM but with
+// PAM files of its own (FU_PAM_CONFDIR), so no test ever counts as a wrong
+// password for the real account.
+
+#include "lockscreencontroller.h"
+
+#include <QCoreApplication>
+#include <QDir>
+#include <QFile>
+#include <QTemporaryDir>
+#include <QTimer>
+
+#include <cstdio>
+
+namespace
+{
+int failures = 0;
+
+void check(bool ok, const char *what)
+{
+    std::printf("%s  %s\n", ok ? "ok  " : "FAIL", what);
+    if (!ok) {
+        ++failures;
+    }
+}
+
+// Types the password into a fresh controller and waits for the verdict:
+// 1 let in, 0 refused, -1 no answer.
+int attempt(const QString &stack, const QString &password, QString *message = nullptr)
+{
+    QTemporaryDir dir;
+    QFile file(dir.filePath(QStringLiteral("face-unlock-lock")));
+    if (!file.open(QIODevice::WriteOnly)) {
+        return -1;
+    }
+    file.write(stack.toUtf8());
+    file.close();
+    qputenv("FU_PAM_CONFDIR", dir.path().toLocal8Bit());
+
+    LockScreenController lock;
+    int verdict = -1;
+    QObject::connect(&lock, &LockScreenController::authenticated, [&] {
+        verdict = 1;
+        QCoreApplication::quit();
+    });
+    QObject::connect(&lock, &LockScreenController::rejected, [&] {
+        verdict = 0;
+        QCoreApplication::quit();
+    });
+    QTimer::singleShot(5000, &QCoreApplication::quit);
+    lock.setPassword(password);
+    lock.submit();
+    QCoreApplication::exec();
+    if (message) {
+        *message = lock.message();
+    }
+    check(lock.password().isEmpty(), "the password is gone once it was checked");
+    return verdict;
+}
+} // namespace
+
+int main(int argc, char **argv)
+{
+    QCoreApplication app(argc, argv);
+
+    check(attempt(QStringLiteral("auth required pam_permit.so\n"), QStringLiteral("secret")) == 1, "a stack that says yes unlocks");
+
+    QString message;
+    check(attempt(QStringLiteral("auth required pam_deny.so\n"), QStringLiteral("secret"), &message) == 0, "a stack that says no does not");
+    check(!message.isEmpty(), "and the screen says so");
+
+    // Nothing typed: nothing to check, and nothing happens.
+    LockScreenController empty;
+    bool answered = false;
+    QObject::connect(&empty, &LockScreenController::authenticated, [&] {
+        answered = true;
+    });
+    empty.submit();
+    check(!empty.busy() && !answered, "an empty password is not sent");
+
+    std::printf("\n%s\n", failures ? "SOME CHECKS FAILED" : "all checks passed");
+    return failures ? 1 : 0;
+}