[gtk] Ext2AttrView: Display the compression algorithm, if available.

XAttrView: Set the compression algorithm in Ext2AttrView.

We're using Ext2AttrView because most Linux file systems that support
compression also support Ext2-style attributes.

src/gtk/xattr/Ext2AttrView.cpp

@@ -15,11 +15,15 @@
 // Ext2AttrData
 #include "librpfile/xattr/Ext2AttrData.h"
 
+// librpfile
+using LibRpFile::XAttrReader;
+
 /* Property identifiers */
 typedef enum {
 	PROP_0,
 
 	PROP_FLAGS,
+	PROP_ZALGORITHM,
 
 	PROP_LAST
 } RpExt2AttrViewPropID;
@@ -67,6 +71,7 @@ struct _RpExt2AttrView {
 	super __parent__;
 
 	int flags;
+	XAttrReader::ZAlgorithm zAlgorithm;
 
 	// Inhibit checkbox toggling while updating.
 	gboolean inhibit_checkbox_no_toggle;
@@ -74,6 +79,9 @@ struct _RpExt2AttrView {
 	// lsattr-style attributes label
 	GtkWidget *lblLsAttr;
 
+	// Compression label
+	GtkWidget *lblCompression;
+
 	// See enum CheckboxID and checkboxInfo.
 	GtkWidget *checkBoxes[EXT2_ATTR_CHECKBOX_MAX];
 };
@@ -103,6 +111,12 @@ rp_ext2_attr_view_class_init(RpExt2AttrViewClass *klass)
 		G_MININT, G_MAXINT, 0,
 		(GParamFlags)(G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY));
 
+	// TODO: Enum?
+	props[PROP_ZALGORITHM] = g_param_spec_uint(
+		"zalgorithm", "zAlgorithm", "Compression algorithm",
+		0, G_MAXUINT, 0,
+		(GParamFlags)(G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY));
+
 	// Install the properties.
 	g_object_class_install_properties(gobject_class, PROP_LAST, props);
 }
@@ -129,6 +143,10 @@ rp_ext2_attr_view_init(RpExt2AttrView *widget)
 	gtk_label_set_attributes(GTK_LABEL(widget->lblLsAttr), attr_lst);
 	pango_attr_list_unref(attr_lst);
 
+	// Compression
+	widget->lblCompression = gtk_label_new("Compression:");
+	gtk_widget_set_name(widget->lblCompression, "lblCompression");
+
 	// Checkboxes
 	int col = 0, row = 0;
 	static const int col_count = 4;
@@ -179,17 +197,26 @@ rp_ext2_attr_view_init(RpExt2AttrView *widget)
 		}
 	}
 
+	// TODO: lblCompression should be right-aligned.
 #if GTK_CHECK_VERSION(4, 0, 0)
 	gtk_box_append(GTK_BOX(hboxLsAttr), lblLsAttrDesc);
 	gtk_box_append(GTK_BOX(hboxLsAttr), widget->lblLsAttr);
+	gtk_box_append(GTK_BOX(hboxLsAttr), widget->lblCompression);
 	gtk_box_append(GTK_BOX(widget), hboxLsAttr);
 	gtk_box_append(GTK_BOX(widget), gridCheckboxes);
+
+	// Don't show lblCompression by default.
+	gtk_widget_set_visible(widget->lblCompression, false);
 #else /* !GTK_CHECK_VERSION(4, 0, 0) */
 	gtk_box_pack_start(GTK_BOX(hboxLsAttr), lblLsAttrDesc, FALSE, FALSE, 0);
 	gtk_box_pack_start(GTK_BOX(hboxLsAttr), widget->lblLsAttr, FALSE, FALSE, 0);
 	gtk_box_pack_start(GTK_BOX(widget), hboxLsAttr, FALSE, FALSE, 0);
+	gtk_box_pack_end(GTK_BOX(hboxLsAttr), widget->lblCompression, FALSE, FALSE, 0);
 	gtk_widget_show_all(hboxLsAttr);
 
+	// Don't show lblCompression by default.
+	gtk_widget_hide(widget->lblCompression);
+
 	gtk_box_pack_start(GTK_BOX(widget), gridCheckboxes, FALSE, FALSE, 0);
 	gtk_widget_show_all(gridCheckboxes);
 #endif /* GTK_CHECK_VERSION(4, 0, 0) */
@@ -317,6 +344,38 @@ rp_ext2_attr_view_update_flags_display(RpExt2AttrView *widget)
 	rp_ext2_attr_view_update_flags_checkboxes(widget);
 }
 
+/**
+ * Update the compression algorithm label.
+ */
+static void
+rp_ext2_attr_view_update_zAlgorithm_label(RpExt2AttrView *widget)
+{
+	const char *s_alg;
+	switch (widget->zAlgorithm) {
+		default:
+		case XAttrReader::ZAlgorithm::None:
+			// No compression...
+			s_alg = nullptr;
+			break;
+		case XAttrReader::ZAlgorithm::ZLIB:
+			s_alg = "zlib";
+			break;
+		case XAttrReader::ZAlgorithm::LZO:
+			s_alg = "lzo";
+			break;
+		case XAttrReader::ZAlgorithm::ZSTD:
+			s_alg = "zstd";
+			break;
+	}
+
+	if (s_alg) {
+		gtk_label_set_text(GTK_LABEL(widget->lblCompression), fmt::format(FSTR("Compression: {:s}"), s_alg).c_str());
+		gtk_widget_set_visible(widget->lblCompression, true);
+	} else {
+		gtk_widget_set_visible(widget->lblCompression, false);
+	}
+}
+
 /** Property accessors / mutators **/
 
 /**
@@ -363,6 +422,44 @@ rp_ext2_attr_view_clear_flags(RpExt2AttrView *widget)
 	}
 }
 
+/**
+ * Set the current compression algorithm.
+ * @return Compression algorithm
+ */
+void
+rp_ext2_attr_view_set_zAlgorithm(RpExt2AttrView *widget, XAttrReader::ZAlgorithm zAlgorithm)
+{
+	if (widget->zAlgorithm != zAlgorithm) {
+		widget->zAlgorithm = zAlgorithm;
+		rp_ext2_attr_view_update_zAlgorithm_label(widget);
+		g_object_notify_by_pspec(G_OBJECT(widget), props[PROP_ZALGORITHM]);
+	}
+}
+
+/**
+ * Set the current compression algorithm.
+ * @param zAlgorithm Compression algorithm
+ */
+XAttrReader::ZAlgorithm
+rp_ext2_attr_view_get_zAlgorithm(RpExt2AttrView *widget)
+{
+	g_return_val_if_fail(RP_IS_EXT2_ATTR_VIEW(widget), XAttrReader::ZAlgorithm::None);
+	return widget->zAlgorithm;
+}
+
+/**
+ * Clear the current compression algorithm.
+ */
+void
+rp_ext2_attr_view_clear_zAlgorithm(RpExt2AttrView *widget)
+{
+	if (widget->zAlgorithm != XAttrReader::ZAlgorithm::None) {
+		widget->zAlgorithm = XAttrReader::ZAlgorithm::None;
+		rp_ext2_attr_view_update_zAlgorithm_label(widget);
+		g_object_notify_by_pspec(G_OBJECT(widget), props[PROP_ZALGORITHM]);
+	}
+}
+
 /** Signal handlers **/
 
 /**

src/gtk/xattr/Ext2AttrView.hpp

@@ -10,6 +10,10 @@
 
 #include "gtk-compat.h"
 
+#ifdef __cplusplus
+#  include "librpfile/xattr/XAttrReader.hpp"
+#endif /* __cplusplus */
+
 G_BEGIN_DECLS
 
 #define RP_TYPE_EXT2_ATTR_VIEW (rp_ext2_attr_view_get_type())
@@ -34,3 +38,9 @@ int 		rp_ext2_attr_view_get_flags		(RpExt2AttrView *widget);
 void		rp_ext2_attr_view_clear_flags		(RpExt2AttrView *widget);
 
 G_END_DECLS
+
+#ifdef __cplusplus
+void					rp_ext2_attr_view_set_zAlgorithm	(RpExt2AttrView *widget, LibRpFile::XAttrReader::ZAlgorithm zAlgorithm);
+LibRpFile::XAttrReader::ZAlgorithm	rp_ext2_attr_view_get_zAlgorithm	(RpExt2AttrView *widget);
+void					rp_ext2_attr_view_clear_zAlgorithm	(RpExt2AttrView *widget);
+#endif /* __cplusplus */

src/gtk/xattr/XAttrView.cpp

@@ -308,7 +308,11 @@ rp_xattr_view_load_ext2_attrs(RpXAttrView *widget)
 	// If we do have attributes, we'll show the widgets there.
 	gtk_widget_set_visible(widget->fraExt2Attributes, false);
 
-	if (!widget->xattrReader->hasExt2Attributes()) {
+	// NOTE: Showing the compression algorithm in Ext2AttrView,
+	// since most file systems that support compression support
+	// Ext2-style attributes.
+	if (!widget->xattrReader->hasExt2Attributes() &&
+	    !widget->xattrReader->hasZAlgorithm()) {
 		// No Ext2 attributes.
 		return -ENOENT;
 	}
@@ -316,6 +320,8 @@ rp_xattr_view_load_ext2_attrs(RpXAttrView *widget)
 	// We have Ext2 attributes.
 	rp_ext2_attr_view_set_flags(RP_EXT2_ATTR_VIEW(widget->ext2AttrView),
 		widget->xattrReader->ext2Attributes());
+	rp_ext2_attr_view_set_zAlgorithm(RP_EXT2_ATTR_VIEW(widget->ext2AttrView),
+		widget->xattrReader->zAlgorithm());
 	gtk_widget_set_visible(widget->fraExt2Attributes, true);
 	return 0;
 }