- handle resolution switch via xrandr without restarting X (#30896)

(nb: doesn't handle dpi switch, and will ask for X restart if the resolution
switch has already been done through xrandr/krandrtray/...)

4 files changed, 22 insertions, 1 deletions

diff --git a/NEWS b/NEWS
index bf3618f..177694d 100644
--- a/NEWS
+++ b/NEWS
@@ -1,3 +1,4 @@
+- handle resolution switch via xrandr without restarting X (#30896)
 - add 1366x768, 1360x768 and 1360x765 resolutions
 - add big standard resolutions (4/3, 16/10, 16/9)
 - [bugfix] fix test message not translated (#30261)
diff --git a/lib/Xconfig/main.pm b/lib/Xconfig/main.pm
index 7fb9c8a..6a4c8cf 100644
--- a/lib/Xconfig/main.pm
+++ b/lib/Xconfig/main.pm
@@ -209,12 +209,15 @@ The current configuration is:
 sub write {
     my ($raw_X, $X) = @_;
     export_to_install_X($X) if $::isInstall;
+    my $only_resolution = $raw_X->is_only_resolution_modified;
     $raw_X->write;
     Xconfig::various::check_XF86Config_symlink();
     symlinkf "../../usr/bin/Xorg", "$::prefix/etc/X11/X";
     if ($X->{resolutions}[0]{bios}) {
 	Xconfig::various::setupFB($X->{resolutions}[0]{bios});
 	'need_reboot';
+    } elsif (my $resolution = $only_resolution && eval { $raw_X->get_resolution }) {
+	'need_xrandr' . sprintf(' --size %dx%d', @$resolution{'X', 'Y'});
     } else {
 	'need_restart';
     }
diff --git a/lib/Xconfig/xfree.pm b/lib/Xconfig/xfree.pm
index 519f2ea..a3dda06 100644
--- a/lib/Xconfig/xfree.pm
+++ b/lib/Xconfig/xfree.pm
@@ -73,6 +73,10 @@ sub is_modified {
     my ($raw_X) = @_;
     $raw_X->{before} ne $raw_X->prepare_write;
 }
+sub is_only_resolution_modified {
+    my ($raw_X) = @_;
+    ($raw_X->{after_set_resolutions} || $raw_X->{before}) eq $raw_X->prepare_write;
+}
 sub empty_config {
     my ($class) = @_;
     $class->new(Xconfig::parse::read_XF86Config_from_string(our $default_header));
@@ -198,6 +202,7 @@ sub set_resolutions {
     my ($raw_X, $resolutions, $o_Screen) = @_;
     
     my $Depth = $resolutions->[0]{Depth} eq '32' ? 24 : $resolutions->[0]{Depth};
+    my $only_resolution = $raw_X->is_only_resolution_modified;
     
     foreach my $Screen ($o_Screen ? $o_Screen : $raw_X->get_Sections('Screen')) {
 	$Screen ||= $raw_X->get_default_screen or internal_error('no screen');
@@ -209,12 +214,15 @@ sub set_resolutions {
 	my @Modes = map { sprintf($Mode_name eq 'Modes' ? '"%dx%d"' : '%d %d', @$_{'X', 'Y'}) } @l;
 	
 	delete $Screen->{DefaultDepth};
+	$only_resolution &&= $Screen->{DefaultColorDepth} && $Screen->{DefaultColorDepth}{val} eq $Depth;
 	$Screen->{DefaultColorDepth} = { val => $Depth };
 	$Screen->{Display} = [ map {
 	    { l => { Depth => { val => $_ }, $Mode_name => { val => join(' ', @Modes) } } };
 	} 8, 15, 16, 24 ];
     }
     add_gtf_ModeLines($raw_X, $resolutions);
+
+    $raw_X->{after_set_resolutions} = $only_resolution ? $raw_X->prepare_write : '';
 }
 
 
diff --git a/tools/XFdrake b/tools/XFdrake
index 19988f3..e9e2b61 100755
--- a/tools/XFdrake
+++ b/tools/XFdrake
@@ -56,7 +56,16 @@ $configure_this ||= $::auto ? 'auto_install' : 'everything';
 	}
     };
     if (!$::auto) {
-	if ($rc eq 'need_restart') {
+	if ($rc =~ /need_xrandr(.*)/) {
+	    my $opts = $1;
+	    my $before = `xrandr`;
+	    run_program::run('xrandr', split(' ', $opts));
+	    my $after = `xrandr`;
+	    if ($before eq $after) {
+		log::l("xrandr $opts failed, defaulting to ask_for_X_restart");
+		any::ask_for_X_restart($in);
+	    }
+	} elsif ($rc eq 'need_restart') {
 	    any::ask_for_X_restart($in);
 	} elsif ($rc eq 'need_reboot') {
 	    $in->ask_warn('', N("You need to reboot for changes to take effect"));