Adding upstream version 3.38.1.upstream/3.38.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 305 insertions, 0 deletions

diff --git a/src/gs-css.c b/src/gs-css.c
new file mode 100644
index 0000000..923ac1a
--- /dev/null
+++ b/src/gs-css.c
@@ -0,0 +1,305 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2017 Richard Hughes <richard@hughsie.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/**
+ * SECTION:gs-css
+ * @title: GsCss
+ * @stability: Unstable
+ * @short_description: Parse, validate and rewrite CSS resources
+ */
+
+#include "config.h"
+
+#include <gtk/gtk.h>
+#include <appstream-glib.h>
+
+#include "gs-css.h"
+
+struct _GsCss
+{
+	GObject			 parent_instance;
+	GHashTable		*ids;
+	GsCssRewriteFunc	 rewrite_func;
+	gpointer		 rewrite_func_data;
+};
+
+G_DEFINE_TYPE (GsCss, gs_css, G_TYPE_OBJECT)
+
+static void
+_cleanup_string (GString *str)
+{
+	/* remove leading newlines */
+	while (g_str_has_prefix (str->str, "\n") || g_str_has_prefix (str->str, " "))
+		g_string_erase (str, 0, 1);
+
+	/* remove trailing newlines */
+	while (g_str_has_suffix (str->str, "\n") || g_str_has_suffix (str->str, " "))
+		g_string_truncate (str, str->len - 1);
+}
+
+/**
+ * gs_css_parse:
+ * @self: a #GsCss
+ * @markup: come CSS, or %NULL
+ * @error: a #GError or %NULL
+ *
+ * Parses the CSS markup and does some basic validation checks on the input.
+ *
+ * Returns: %TRUE for success
+ */
+gboolean
+gs_css_parse (GsCss *self, const gchar *markup, GError **error)
+{
+	g_auto(GStrv) parts = NULL;
+	g_autoptr(GString) markup_str = NULL;
+
+	/* no data */
+	if (markup == NULL || markup[0] == '\0')
+		return TRUE;
+
+	/* old style, no IDs */
+	markup_str = g_string_new (markup);
+	as_utils_string_replace (markup_str, "@datadir@", DATADIR);
+	if (!g_str_has_prefix (markup_str->str, "#")) {
+		g_hash_table_insert (self->ids,
+				     g_strdup ("tile"),
+				     g_string_free (g_steal_pointer (&markup_str), FALSE));
+		return TRUE;
+	}
+
+	/* split up CSS into ID chunks, e.g.
+	 *
+	 *    #tile {border-radius: 0;}
+	 *    #name {color: white;}
+	 */
+	parts = g_strsplit (markup_str->str + 1, "\n#", -1);
+	for (guint i = 0; parts[i] != NULL; i++) {
+		g_autoptr(GString) current_css = NULL;
+		g_autoptr(GString) current_key = NULL;
+		for (guint j = 1; parts[i][j] != '\0'; j++) {
+			const gchar ch = parts[i][j];
+			if (ch == '{') {
+				if (current_key != NULL || current_css != NULL) {
+					g_set_error_literal (error,
+							     G_IO_ERROR,
+							     G_IO_ERROR_INVALID_DATA,
+							     "invalid '{'");
+					return FALSE;
+				}
+				current_key = g_string_new_len (parts[i], j);
+				current_css = g_string_new (NULL);
+				_cleanup_string (current_key);
+
+				/* already added */
+				if (g_hash_table_lookup (self->ids, current_key->str) != NULL) {
+					g_set_error (error,
+						     G_IO_ERROR,
+						     G_IO_ERROR_INVALID_DATA,
+						     "duplicate ID '%s'",
+						     current_key->str);
+					return FALSE;
+				}
+				continue;
+			}
+			if (ch == '}') {
+				if (current_key == NULL || current_css == NULL) {
+					g_set_error_literal (error,
+							     G_IO_ERROR,
+							     G_IO_ERROR_INVALID_DATA,
+							     "invalid '}'");
+					return FALSE;
+				}
+				_cleanup_string (current_css);
+				g_hash_table_insert (self->ids,
+						     g_string_free (current_key, FALSE),
+						     g_string_free (current_css, FALSE));
+				current_key = NULL;
+				current_css = NULL;
+				continue;
+			}
+			if (current_css != NULL)
+				g_string_append_c (current_css, ch);
+		}
+		if (current_key != NULL || current_css != NULL) {
+			g_set_error_literal (error,
+					     G_IO_ERROR,
+					     G_IO_ERROR_INVALID_DATA,
+					     "missing '}'");
+			return FALSE;
+		}
+	}
+
+	/* success */
+	return TRUE;
+}
+
+/**
+ * gs_css_get_markup_for_id:
+ * @self: a #GsCss
+ * @id: an ID, or %NULL for the default
+ *
+ * Gets the CSS markup for a specific ID.
+ *
+ * Returns: %TRUE for success
+ */
+const gchar *
+gs_css_get_markup_for_id (GsCss *self, const gchar *id)
+{
+	if (id == NULL)
+		id = "tile";
+	return g_hash_table_lookup (self->ids, id);
+}
+
+static void
+_css_parsing_error_cb (GtkCssProvider *provider,
+		       GtkCssSection *section,
+		       GError *error,
+		       gpointer user_data)
+{
+	GError **error_parse = (GError **) user_data;
+	if (*error_parse != NULL) {
+		g_warning ("ignoring parse error %u:%u: %s",
+			   gtk_css_section_get_start_line (section),
+			   gtk_css_section_get_start_position (section),
+			   error->message);
+		return;
+	}
+	*error_parse = g_error_copy (error);
+}
+
+static gboolean
+gs_css_validate_part (GsCss *self, const gchar *markup, GError **error)
+{
+	g_autofree gchar *markup_new = NULL;
+	g_autoptr(GError) error_parse = NULL;
+	g_autoptr(GString) str = NULL;
+	g_autoptr(GtkCssProvider) provider = NULL;
+
+	/* nothing set */
+	if (markup == NULL)
+		return TRUE;
+
+	/* remove custom class if NULL */
+	str = g_string_new (NULL);
+	g_string_append (str, ".themed-widget {");
+	if (self->rewrite_func != NULL) {
+		markup_new = self->rewrite_func (self->rewrite_func_data,
+						 markup,
+						 error);
+		if (markup_new == NULL)
+			return FALSE;
+	} else {
+		markup_new = g_strdup (markup);
+	}
+	g_string_append (str, markup_new);
+	g_string_append (str, "}");
+
+	/* set up custom provider */
+	provider = gtk_css_provider_new ();
+	g_signal_connect (provider, "parsing-error",
+			  G_CALLBACK (_css_parsing_error_cb), &error_parse);
+	gtk_style_context_add_provider_for_screen (gdk_screen_get_default (),
+						   GTK_STYLE_PROVIDER (provider),
+						   GTK_STYLE_PROVIDER_PRIORITY_APPLICATION);
+	gtk_css_provider_load_from_data (provider, str->str, -1, NULL);
+	if (error_parse != NULL) {
+		if (error != NULL)
+			*error = g_error_copy (error_parse);
+		return FALSE;
+	}
+	return TRUE;
+}
+
+/**
+ * gs_css_validate:
+ * @self: a #GsCss
+ * @error: a #GError or %NULL
+ *
+ * Validates each part of the CSS markup.
+ *
+ * Returns: %TRUE for success
+ */
+gboolean
+gs_css_validate (GsCss *self, GError **error)
+{
+	g_autoptr(GList) keys = NULL;
+
+	/* check each CSS ID */
+	keys = g_hash_table_get_keys (self->ids);
+	for (GList *l = keys; l != NULL; l = l->next) {
+		const gchar *tmp;
+		const gchar *id = l->data;
+		if (g_strcmp0 (id, "tile") != 0 &&
+		    g_strcmp0 (id, "name") != 0 &&
+		    g_strcmp0 (id, "summary") != 0) {
+			g_set_error (error,
+				     G_IO_ERROR,
+				     G_IO_ERROR_INVALID_DATA,
+				     "Invalid CSS ID '%s'",
+				     id);
+			return FALSE;
+		}
+		tmp = g_hash_table_lookup (self->ids, id);
+		if (!gs_css_validate_part (self, tmp, error))
+			return FALSE;
+	}
+
+	/* success */
+	return TRUE;
+}
+
+/**
+ * gs_css_set_rewrite_func:
+ * @self: a #GsCss
+ * @func: a #GsCssRewriteFunc or %NULL
+ * @user_data: user data to pass to @func
+ *
+ * Sets a function to be used when rewriting CSS before it is parsed.
+ *
+ * Returns: %TRUE for success
+ */
+void
+gs_css_set_rewrite_func (GsCss *self, GsCssRewriteFunc func, gpointer user_data)
+{
+	self->rewrite_func = func;
+	self->rewrite_func_data = user_data;
+}
+
+static void
+gs_css_finalize (GObject *object)
+{
+	GsCss *self = GS_CSS (object);
+	g_hash_table_unref (self->ids);
+	G_OBJECT_CLASS (gs_css_parent_class)->finalize (object);
+}
+
+static void
+gs_css_class_init (GsCssClass *klass)
+{
+	GObjectClass *object_class = G_OBJECT_CLASS (klass);
+	object_class->finalize = gs_css_finalize;
+}
+
+static void
+gs_css_init (GsCss *self)
+{
+	self->ids = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, g_free);
+}
+
+/**
+ * gs_css_new:
+ *
+ * Return value: a new #GsCss object.
+ **/
+GsCss *
+gs_css_new (void)
+{
+	GsCss *self;
+	self = g_object_new (GS_TYPE_CSS, NULL);
+	return GS_CSS (self);
+}