Use xcb_cursor library instead of Xlib based one in Cursor

Straight forward port from XLib based XCursor library to the
xcb variant which is considerably new. The xcb variant only allows
to create xcb_cursor_t for the default theme and size. Which suits
the needs in Cursor quite well, but means it's not a replacement for
the usage in zoom effect.

REVIEW: 122290

CMakeLists.txt

@@ -173,6 +173,7 @@ find_package(XCB
         GLX
     OPTIONAL_COMPONENTS
         ICCCM
+        CURSOR
 )
 set_package_properties(XCB PROPERTIES TYPE REQUIRED)
 
@@ -181,6 +182,7 @@ if (XCB_ICCCM_VERSION VERSION_LESS "0.4")
     set(XCB_ICCCM_FOUND FALSE)
 endif()
 add_feature_info("XCB-ICCCM" XCB_ICCCM_FOUND "Required for building test applications for KWin")
+add_feature_info("XCB-CURSOR" XCB_CURSOR_FOUND "Required for XCursor support")
 
 feature_summary(WHAT ALL INCLUDE_QUIET_PACKAGES FATAL_ON_MISSING_REQUIRED_PACKAGES)
 
@@ -260,6 +262,12 @@ else()
     set(HAVE_WAYLAND_EGL FALSE)
 endif()
 
+if(XCB_CURSOR_FOUND)
+    set(HAVE_XCB_CURSOR ${XCB_CURSOR_FOUND})
+else()
+    set(HAVE_XCB_CURSOR FALSE)
+endif()
+
 include(CheckIncludeFiles)
 check_include_files(unistd.h HAVE_UNISTD_H)
 check_include_files(malloc.h HAVE_MALLOC_H)
@@ -464,7 +472,6 @@ set(kwin_KDE_LIBS
 set(kwin_XLIB_LIBS
     ${X11_X11_LIB}
     ${X11_Xext_LIB}
-    ${X11_Xcursor_LIB}
     ${X11_ICE_LIB}
     ${X11_SM_LIB}
 )
@@ -500,6 +507,10 @@ if(KWIN_BUILD_ACTIVITIES)
     set(kwin_KDE_LIBS ${kwin_KDE_LIBS} KF5::Activities)
 endif()
 
+if(HAVE_XCB_CURSOR)
+    set(kwin_XCB_LIBS ${kwin_XCB_LIBS} XCB::CURSOR)
+endif()
+
 set(kwinLibs
     ${kwin_OWN_LIBS}
     ${kwin_QT_LIBS}

config-kwin.h.cmake

@@ -13,6 +13,7 @@
 #cmakedefine01 HAVE_WAYLAND_EGL
 #cmakedefine01 HAVE_XKB
 #cmakedefine01 HAVE_INPUT
+#cmakedefine01 HAVE_XCB_CURSOR
 
 /* Define to 1 if you have the <unistd.h> header file. */
 #cmakedefine HAVE_UNISTD_H 1

cursor.cpp

@@ -33,11 +33,11 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include <QDBusConnection>
 #include <QScreen>
 #include <QTimer>
-// Xlib
-#include <X11/Xcursor/Xcursor.h>
-#include <fixx11h.h>
 // xcb
 #include <xcb/xfixes.h>
+#if HAVE_XCB_CURSOR
+#include <xcb/xcb_cursor.h>
+#endif
 
 namespace KWin
 {
@@ -353,15 +353,20 @@ xcb_cursor_t X11Cursor::createCursor(const QByteArray &name)
     if (name.isEmpty()) {
         return XCB_CURSOR_NONE;
     }
-    // XCursor is an XLib only lib
-    XcursorImage *ximg = XcursorLibraryLoadImage(name.constData(), themeName().toUtf8().constData(), themeSize());
-    if (!ximg) {
+#if HAVE_XCB_CURSOR
+    xcb_cursor_context_t *ctx;
+    if (xcb_cursor_context_new(connection(), defaultScreen(), &ctx) < 0) {
         return XCB_CURSOR_NONE;
     }
-    xcb_cursor_t cursor = XcursorImageLoadCursor(display(), ximg);
-    XcursorImageDestroy(ximg);
-    m_cursors.insert(name, cursor);
+    const xcb_cursor_t cursor = xcb_cursor_load_cursor(ctx, name.constData());
+    if (cursor != XCB_CURSOR_NONE) {
+        m_cursors.insert(name, cursor);
+    }
+    xcb_cursor_context_free(ctx);
     return cursor;
+#else
+    return XCB_CURSOR_NONE;
+#endif
 }
 
 QByteArray Cursor::cursorName(Qt::CursorShape shape) const

kcmkwin/kwinrules/CMakeLists.txt

@@ -16,7 +16,6 @@ kf5_add_kdeinit_executable( kwin_rules_dialog ${kwin_rules_dialog_KDEINIT_SRCS})
 set(kwin_kcm_rules_XCB_LIBS
     XCB::XCB
     XCB::XFIXES
-    ${X11_Xcursor_LIB}
 )
 
 set(kcm_libs
@@ -35,6 +34,10 @@ if(KWIN_BUILD_ACTIVITIES)
     set(kcm_libs ${kcm_libs} KF5::Activities)
 endif()
 
+if(HAVE_XCB_CURSOR)
+    set(kwin_kcm_rules_XCB_LIBS ${kwin_kcm_rules_XCB_LIBS} XCB::CURSOR)
+endif()
+
 target_link_libraries(kdeinit_kwin_rules_dialog ${kcm_libs} ${kwin_kcm_rules_XCB_LIBS})
 
 install(TARGETS kdeinit_kwin_rules_dialog ${INSTALL_TARGETS_DEFAULT_ARGS} )