Advance Wayland and KDE package bring-up

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

local/recipes/kde/kwin/source/src/utils/ramfile.cpp

@@ -0,0 +1,164 @@
+/*
+    KWin - the KDE window manager
+    This file is part of the KDE project.
+
+    SPDX-FileCopyrightText: 2022 MBition GmbH
+    SPDX-FileContributor: Kai Uwe Broulik <kai_uwe.broulik@mbition.io>
+
+    SPDX-License-Identifier: GPL-2.0-or-later
+*/
+
+#include "ramfile.h"
+#include "common.h" // for logging
+
+#include <QScopeGuard>
+
+#include <cerrno>
+#include <fcntl.h>
+#include <sys/mman.h>
+#include <unistd.h>
+#include <utility>
+
+namespace KWin
+{
+
+RamFile::RamFile(const char *name, const void *inData, int size, RamFile::Flags flags)
+    : m_size(size)
+    , m_flags(flags)
+{
+    auto guard = qScopeGuard([this] {
+        cleanup();
+    });
+
+#if HAVE_MEMFD
+    m_fd = FileDescriptor(memfd_create(name, MFD_CLOEXEC | MFD_ALLOW_SEALING));
+    if (!m_fd.isValid()) {
+        qCWarning(KWIN_CORE).nospace() << name << ": Can't create memfd: " << strerror(errno);
+        return;
+    }
+
+    if (ftruncate(m_fd.get(), size) < 0) {
+        qCWarning(KWIN_CORE).nospace() << name << ": Failed to ftruncate memfd: " << strerror(errno);
+        return;
+    }
+
+    void *data = mmap(nullptr, size, PROT_READ | PROT_WRITE, MAP_SHARED, m_fd.get(), 0);
+    if (data == MAP_FAILED) {
+        qCWarning(KWIN_CORE).nospace() << name << ": mmap failed: " << strerror(errno);
+        return;
+    }
+#else
+    m_tmp = std::make_unique<QTemporaryFile>();
+    if (!m_tmp->open()) {
+        qCWarning(KWIN_CORE).nospace() << name << ": Can't open temporary file";
+        return;
+    }
+
+    if (unlink(m_tmp->fileName().toUtf8().constData()) != 0) {
+        qCWarning(KWIN_CORE).nospace() << name << ": Failed to remove temporary file from filesystem: " << strerror(errno);
+    }
+
+    if (!m_tmp->resize(size)) {
+        qCWarning(KWIN_CORE).nospace() << name << ": Failed to resize temporary file";
+        return;
+    }
+
+    uchar *data = m_tmp->map(0, size);
+    if (!data) {
+        qCWarning(KWIN_CORE).nospace() << name << ": map failed";
+        return;
+    }
+#endif
+
+    memcpy(data, inData, size);
+
+#if HAVE_MEMFD
+    munmap(data, size);
+#else
+    m_tmp->unmap(data);
+#endif
+
+    int seals = F_SEAL_SHRINK | F_SEAL_GROW | F_SEAL_SEAL;
+    if (flags.testFlag(RamFile::Flag::SealWrite)) {
+        seals |= F_SEAL_WRITE;
+    }
+    // This can fail for QTemporaryFile based on the underlying file system.
+    if (fcntl(fd(), F_ADD_SEALS, seals) != 0) {
+        qCDebug(KWIN_CORE).nospace() << name << ": Failed to seal RamFile: " << strerror(errno);
+    }
+
+    guard.dismiss();
+}
+
+RamFile::RamFile(RamFile &&other) Q_DECL_NOEXCEPT
+    : m_size(std::exchange(other.m_size, 0))
+    , m_flags(std::exchange(other.m_flags, RamFile::Flags{}))
+#if HAVE_MEMFD
+    , m_fd(std::exchange(other.m_fd, KWin::FileDescriptor{}))
+#else
+    , m_tmp(std::exchange(other.m_tmp, {}))
+#endif
+{
+}
+
+RamFile &RamFile::operator=(RamFile &&other) Q_DECL_NOEXCEPT
+{
+    cleanup();
+    m_size = std::exchange(other.m_size, 0);
+    m_flags = std::exchange(other.m_flags, RamFile::Flags{});
+#if HAVE_MEMFD
+    m_fd = std::exchange(other.m_fd, KWin::FileDescriptor{});
+#else
+    m_tmp = std::exchange(other.m_tmp, {});
+#endif
+    return *this;
+}
+
+RamFile::~RamFile()
+{
+    cleanup();
+}
+
+void RamFile::cleanup()
+{
+#if HAVE_MEMFD
+    m_fd = KWin::FileDescriptor();
+#else
+    m_tmp.reset();
+#endif
+}
+
+bool RamFile::isValid() const
+{
+    return fd() != -1;
+}
+
+RamFile::Flags RamFile::effectiveFlags() const
+{
+    Flags flags = {};
+
+    const int seals = fcntl(fd(), F_GET_SEALS);
+    if (seals > 0) {
+        if (seals & F_SEAL_WRITE) {
+            flags.setFlag(Flag::SealWrite);
+        }
+    }
+
+    return flags;
+}
+
+int RamFile::fd() const
+{
+#if HAVE_MEMFD
+    return m_fd.get();
+#else
+    return m_tmp->handle();
+#endif
+}
+
+int RamFile::size() const
+{
+    return m_size;
+}
+
+} // namespace KWin