--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mupdf-source/source/xps/xps-resource.c	Mon Sep 15 11:43:07 2025 +0200
@@ -0,0 +1,183 @@
+// Copyright (C) 2004-2021 Artifex Software, Inc.
+//
+// This file is part of MuPDF.
+//
+// MuPDF is free software: you can redistribute it and/or modify it under the
+// terms of the GNU Affero General Public License as published by the Free
+// Software Foundation, either version 3 of the License, or (at your option)
+// any later version.
+//
+// MuPDF is distributed in the hope that it will be useful, but WITHOUT ANY
+// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+// FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
+// details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with MuPDF. If not, see <https://www.gnu.org/licenses/agpl-3.0.en.html>
+//
+// Alternative licensing terms are available from the licensor.
+// For commercial licensing, see <https://www.artifex.com/> or contact
+// Artifex Software, Inc., 39 Mesa Street, Suite 108A, San Francisco,
+// CA 94129, USA, for further information.
+
+#include "mupdf/fitz.h"
+#include "xps-imp.h"
+
+#include <string.h>
+
+static fz_xml *
+xps_lookup_resource(fz_context *ctx, xps_document *doc, xps_resource *dict, char *name, char **urip)
+{
+	xps_resource *head, *node;
+	for (head = dict; head; head = head->parent)
+	{
+		for (node = head; node; node = node->next)
+		{
+			if (!strcmp(node->name, name))
+			{
+				if (urip && head->base_uri)
+					*urip = head->base_uri;
+				return node->data;
+			}
+		}
+	}
+	return NULL;
+}
+
+static fz_xml *
+xps_parse_resource_reference(fz_context *ctx, xps_document *doc, xps_resource *dict, char *att, char **urip)
+{
+	char name[1024];
+	char *s;
+
+	if (strstr(att, "{StaticResource ") != att)
+		return NULL;
+
+	fz_strlcpy(name, att + 16, sizeof name);
+	s = strrchr(name, '}');
+	if (s)
+		*s = 0;
+
+	return xps_lookup_resource(ctx, doc, dict, name, urip);
+}
+
+void
+xps_resolve_resource_reference(fz_context *ctx, xps_document *doc, xps_resource *dict,
+		char **attp, fz_xml **tagp, char **urip)
+{
+	if (*attp)
+	{
+		fz_xml *rsrc = xps_parse_resource_reference(ctx, doc, dict, *attp, urip);
+		if (rsrc)
+		{
+			*attp = NULL;
+			*tagp = rsrc;
+		}
+	}
+}
+
+static xps_resource *
+xps_parse_remote_resource_dictionary(fz_context *ctx, xps_document *doc, char *base_uri, char *source_att)
+{
+	char part_name[1024];
+	char part_uri[1024];
+	xps_part *part;
+	xps_resource *dict = NULL;
+	fz_xml_doc *xml = NULL;
+	char *s;
+
+	fz_var(xml);
+
+	/* External resource dictionaries MUST NOT reference other resource dictionaries */
+	xps_resolve_url(ctx, doc, part_name, base_uri, source_att, sizeof part_name);
+
+	part = xps_read_part(ctx, doc, part_name);
+	fz_try(ctx)
+	{
+		xml = fz_parse_xml(ctx, part->data, 0);
+		if (!fz_xml_is_tag(fz_xml_root(xml), "ResourceDictionary"))
+			fz_throw(ctx, FZ_ERROR_FORMAT, "expected ResourceDictionary element");
+
+		fz_strlcpy(part_uri, part_name, sizeof part_uri);
+		s = strrchr(part_uri, '/');
+		if (s)
+			s[1] = 0;
+
+		dict = xps_parse_resource_dictionary(ctx, doc, part_uri, fz_xml_root(xml));
+		if (dict)
+		{
+			dict->base_xml = xml; /* pass on ownership */
+			xml = NULL;
+		}
+	}
+	fz_always(ctx)
+	{
+		xps_drop_part(ctx, doc, part);
+		fz_drop_xml(ctx, xml);
+	}
+	fz_catch(ctx)
+	{
+		fz_rethrow(ctx);
+	}
+
+	return dict;
+}
+
+xps_resource *
+xps_parse_resource_dictionary(fz_context *ctx, xps_document *doc, char *base_uri, fz_xml *root)
+{
+	xps_resource *head;
+	xps_resource *entry;
+	fz_xml *node;
+	char *source;
+	char *key;
+
+	source = fz_xml_att(root, "Source");
+	if (source)
+		return xps_parse_remote_resource_dictionary(ctx, doc, base_uri, source);
+
+	head = NULL;
+
+	for (node = fz_xml_down(root); node; node = fz_xml_next(node))
+	{
+		key = fz_xml_att(node, "x:Key");
+		if (key)
+		{
+			entry = fz_malloc_struct(ctx, xps_resource);
+			entry->name = key;
+			entry->base_uri = NULL;
+			entry->base_xml = NULL;
+			entry->data = node;
+			entry->next = head;
+			entry->parent = NULL;
+			head = entry;
+		}
+	}
+
+	if (head)
+	{
+		fz_try(ctx)
+			head->base_uri = fz_strdup(ctx, base_uri);
+		fz_catch(ctx)
+		{
+			fz_free(ctx, entry);
+			fz_rethrow(ctx);
+		}
+	}
+
+	return head;
+}
+
+void
+xps_drop_resource_dictionary(fz_context *ctx, xps_document *doc, xps_resource *dict)
+{
+	xps_resource *next;
+	while (dict)
+	{
+		next = dict->next;
+		fz_drop_xml(ctx, dict->base_xml);
+		fz_free(ctx, dict->base_uri);
+		fz_free(ctx, dict);
+		dict = next;
+	}
+}