Fix screen recording when pipewire is started after kwin (#1)

This fixes screen recording when pipewire is started after kwin.
In my specific case, I use an autostart script.

Reviewed-on: #1
Co-authored-by: Tsaop <leeroy@cock.li>
Co-committed-by: Tsaop <leeroy@cock.li>

kwin/.signature

@@ -1,5 +0,0 @@
-untrusted comment: verify with /etc/ports/kde-plasma-6.pub
-RWTGxEYrvi0p3snzPSUTg02d675XCVVPO/v9sCXpPVYY87rVPpo+hdbLkN55Bkm4cocOIUNeWw+1v2EHwJAGmafTgAngZES3UQs=
-SHA256 (Pkgfile) = 292c15cc9b759b4af2f9c1a1d3ec1cd6ed3e74fbbde4f58d09aac71883176e13
-SHA256 (.footprint) = 6e68ef8832d6e6657ed43d2db545437759acef90378a8c94856f4ac0d995d180
-SHA256 (kwin-6.0.3.1.tar.xz) = f15108a993206b962a3c5835b988a0b4922c0a9bc9ab80faf6b36a334d321b33

kwin/Pkgfile

@@ -5,10 +5,15 @@
 
 name=kwin
 version=6.0.3.1
-release=1
-source=(https://download.kde.org/stable/plasma/${version::5}/$name-$version.tar.xz)
+release=2
+source=(https://download.kde.org/stable/plasma/${version::5}/$name-$version.tar.xz
+        fix-screencast-pipewire.patch)
 
 build() {
+
+    # https://bugs.kde.org/show_bug.cgi?id=483137
+    patch -Np1 -d $name-$version -i $SRC/fix-screencast-pipewire.patch
+
     cmake -S $name-$version -B build -G Ninja \
         -D CMAKE_INSTALL_PREFIX=/usr \
         -D CMAKE_INSTALL_LIBDIR=lib \

kwin/fix-screencast-pipewire.patch

@@ -0,0 +1,128 @@
+diff --git a/src/plugins/screencast/pipewirecore.cpp b/src/plugins/screencast/pipewirecore.cpp
+index 077854c65e..eabf89a852 100644
+--- a/src/plugins/screencast/pipewirecore.cpp
++++ b/src/plugins/screencast/pipewirecore.cpp
+@@ -94,6 +94,18 @@ bool PipeWireCore::init()
+     return true;
+ }
+ 
++std::shared_ptr<PipeWireCore> PipeWireCore::self()
++{
++    static std::weak_ptr<PipeWireCore> global;
++    auto ret = global.lock();
++    if (!ret) {
++        ret = std::make_shared<PipeWireCore>();
++        ret->init();
++        global = ret;
++    }
++    return ret;
++}
++
+ } // namespace KWin
+ 
+ #include "moc_pipewirecore.cpp"
+diff --git a/src/plugins/screencast/screencastmanager.cpp b/src/plugins/screencast/screencastmanager.cpp
+index 87c84e93f3..d0a2d6552d 100644
+--- a/src/plugins/screencast/screencastmanager.cpp
++++ b/src/plugins/screencast/screencastmanager.cpp
+@@ -10,7 +10,6 @@
+ #include "core/output.h"
+ #include "core/outputbackend.h"
+ #include "outputscreencastsource.h"
+-#include "pipewirecore.h"
+ #include "regionscreencastsource.h"
+ #include "screencaststream.h"
+ #include "wayland/display.h"
+@@ -27,9 +26,7 @@ namespace KWin
+ 
+ ScreencastManager::ScreencastManager()
+     : m_screencast(new ScreencastV1Interface(waylandServer()->display(), this))
+-    , m_core(new PipeWireCore)
+ {
+-    m_core->init();
+     connect(m_screencast, &ScreencastV1Interface::windowScreencastRequested, this, &ScreencastManager::streamWindow);
+     connect(m_screencast, &ScreencastV1Interface::outputScreencastRequested, this, &ScreencastManager::streamWaylandOutput);
+     connect(m_screencast, &ScreencastV1Interface::virtualOutputScreencastRequested, this, &ScreencastManager::streamVirtualOutput);
+@@ -46,7 +43,7 @@ void ScreencastManager::streamWindow(ScreencastStreamV1Interface *waylandStream,
+         return;
+     }
+ 
+-    auto stream = new ScreenCastStream(new WindowScreenCastSource(window), m_core, this);
++    auto stream = new ScreenCastStream(new WindowScreenCastSource(window), this);
+     stream->setObjectName(window->desktopFileName());
+     stream->setCursorMode(mode, 1, window->clientGeometry());
+ 
+@@ -88,7 +85,7 @@ void ScreencastManager::streamOutput(ScreencastStreamV1Interface *waylandStream,
+         return;
+     }
+ 
+-    auto stream = new ScreenCastStream(new OutputScreenCastSource(streamOutput), m_core, this);
++    auto stream = new ScreenCastStream(new OutputScreenCastSource(streamOutput), this);
+     stream->setObjectName(streamOutput->name());
+     stream->setCursorMode(mode, streamOutput->scale(), streamOutput->geometry());
+ 
+@@ -112,7 +109,7 @@ void ScreencastManager::streamRegion(ScreencastStreamV1Interface *waylandStream,
+     }
+ 
+     auto source = new RegionScreenCastSource(geometry, scale);
+-    auto stream = new ScreenCastStream(source, m_core, this);
++    auto stream = new ScreenCastStream(source, this);
+     stream->setObjectName(rectToString(geometry));
+     stream->setCursorMode(mode, scale, geometry);
+ 
+diff --git a/src/plugins/screencast/screencastmanager.h b/src/plugins/screencast/screencastmanager.h
+index 059e64b545..c4829c0bd0 100644
+--- a/src/plugins/screencast/screencastmanager.h
++++ b/src/plugins/screencast/screencastmanager.h
+@@ -16,7 +16,6 @@ namespace KWin
+ {
+ class Output;
+ class ScreenCastStream;
+-class PipeWireCore;
+ 
+ class ScreencastManager : public Plugin
+ {
+@@ -47,7 +46,6 @@ private:
+     void integrateStreams(ScreencastStreamV1Interface *waylandStream, ScreenCastStream *stream);
+ 
+     ScreencastV1Interface *m_screencast;
+-    std::shared_ptr<PipeWireCore> m_core;
+ };
+ 
+ } // namespace KWin
+diff --git a/src/plugins/screencast/screencaststream.cpp b/src/plugins/screencast/screencaststream.cpp
+index 43d5044c17..183389704b 100644
+--- a/src/plugins/screencast/screencaststream.cpp
++++ b/src/plugins/screencast/screencaststream.cpp
+@@ -321,9 +321,8 @@ void ScreenCastStream::onStreamRenegotiateFormat(uint64_t)
+     pw_stream_update_params(m_pwStream, params.data(), params.count());
+ }
+ 
+-ScreenCastStream::ScreenCastStream(ScreenCastSource *source, std::shared_ptr<PipeWireCore> pwCore, QObject *parent)
++ScreenCastStream::ScreenCastStream(ScreenCastSource *source, QObject *parent)
+     : QObject(parent)
+-    , m_pwCore(pwCore)
+     , m_source(source)
+     , m_resolution(source->textureSize())
+ {
+@@ -364,6 +363,7 @@ ScreenCastStream::~ScreenCastStream()
+ 
+ bool ScreenCastStream::init()
+ {
++    m_pwCore = PipeWireCore::self();
+     if (!m_pwCore->m_error.isEmpty()) {
+         m_error = m_pwCore->m_error;
+         return false;
+diff --git a/src/plugins/screencast/screencaststream.h b/src/plugins/screencast/screencaststream.h
+index 5abf2dd0bb..9afe32e080 100644
+--- a/src/plugins/screencast/screencaststream.h
++++ b/src/plugins/screencast/screencaststream.h
+@@ -48,7 +48,7 @@ class KWIN_EXPORT ScreenCastStream : public QObject
+ {
+     Q_OBJECT
+ public:
+-    explicit ScreenCastStream(ScreenCastSource *source, std::shared_ptr<PipeWireCore> pwCore, QObject *parent);
++    explicit ScreenCastStream(ScreenCastSource *source, QObject *parent);
+     ~ScreenCastStream();
+ 
+     bool init();