Refactor XML serializer such that passing context is easier

Author: nielsdos

ext/dom/xml_serializer.c

@@ -66,9 +66,13 @@ typedef struct {
 	const xmlChar *prefix, *name;
 } dom_qname_pair;
 
+typedef struct dom_xml_serialize_ctx {
+	xmlSaveCtxtPtr ctxt;
+	xmlOutputBufferPtr out;
+} dom_xml_serialize_ctx;
+
 static int dom_xml_serialization_algorithm(
-	xmlSaveCtxtPtr ctxt,
-	xmlOutputBufferPtr out,
+	dom_xml_serialize_ctx *ctx,
 	dom_xml_ns_prefix_map *namespace_prefix_map,
 	xmlNodePtr node,
 	const xmlChar *namespace,
@@ -895,8 +899,7 @@ static int dom_xml_output_indents(xmlOutputBufferPtr out, int indent)
 
 /* https://w3c.github.io/DOM-Parsing/#dfn-xml-serializing-an-element-node */
 static int dom_xml_serialize_element_node(
-	xmlSaveCtxtPtr ctxt,
-	xmlOutputBufferPtr out,
+	dom_xml_serialize_ctx *ctx,
 	const xmlChar *namespace,
 	dom_xml_ns_prefix_map *namespace_prefix_map,
 	xmlNodePtr element,
@@ -916,7 +919,7 @@ static int dom_xml_serialize_element_node(
 	bool should_format = indent >= 0 && element->children != NULL && dom_xml_should_format_element(element);
 
 	/* 2. Let markup be the string "<" (U+003C LESS-THAN SIGN). */
-	TRY(xmlOutputBufferWriteLit(out, "<"));
+	TRY(xmlOutputBufferWriteLit(ctx->out, "<"));
 
 	/* 3. Let qualified name be an empty string.
 	 *    => We're going to do it a bit differently.
@@ -966,7 +969,7 @@ static int dom_xml_serialize_element_node(
 		}
 
 		/* 11.4. Append the value of qualified name to markup. */
-		TRY_OR_CLEANUP(dom_xml_output_qname(out, &qualified_name));
+		TRY_OR_CLEANUP(dom_xml_output_qname(ctx->out, &qualified_name));
 	}
 	/* 12. Otherwise, inherited ns is not equal to ns */
 	else {
@@ -1011,7 +1014,7 @@ static int dom_xml_serialize_element_node(
 			}
 
 			/* 12.4.3. Append the value of qualified name to markup. */
-			TRY_OR_CLEANUP(dom_xml_output_qname(out, &qualified_name));
+			TRY_OR_CLEANUP(dom_xml_output_qname(ctx->out, &qualified_name));
 		}
 		/* 12.5. Otherwise, if prefix is not null, then: */
 		else if (prefix != NULL) {
@@ -1033,14 +1036,14 @@ static int dom_xml_serialize_element_node(
 			qualified_name.name = element->name;
 
 			/* 12.5.4. Append the value of qualified name to markup. */
-			TRY_OR_CLEANUP(dom_xml_output_qname(out, &qualified_name));
+			TRY_OR_CLEANUP(dom_xml_output_qname(ctx->out, &qualified_name));
 
 			/* 12.5.5. Append the following to markup, in the order listed: ... */
-			TRY_OR_CLEANUP(xmlOutputBufferWriteLit(out, " xmlns:")); /* 12.5.5.1 - 12.5.5.2 */
-			TRY_OR_CLEANUP(xmlOutputBufferWriteString(out, (const char *) prefix));
-			TRY_OR_CLEANUP(xmlOutputBufferWriteLit(out, "=\""));
-			TRY_OR_CLEANUP(dom_xml_common_text_serialization(out, (const char *) ns, true));
-			TRY_OR_CLEANUP(xmlOutputBufferWriteLit(out, "\""));
+			TRY_OR_CLEANUP(xmlOutputBufferWriteLit(ctx->out, " xmlns:")); /* 12.5.5.1 - 12.5.5.2 */
+			TRY_OR_CLEANUP(xmlOutputBufferWriteString(ctx->out, (const char *) prefix));
+			TRY_OR_CLEANUP(xmlOutputBufferWriteLit(ctx->out, "=\""));
+			TRY_OR_CLEANUP(dom_xml_common_text_serialization(ctx->out, (const char *) ns, true));
+			TRY_OR_CLEANUP(xmlOutputBufferWriteLit(ctx->out, "\""));
 
 			/* 12.5.6. If local default namespace is not null ... (editorial numbering error: https://github.com/w3c/DOM-Parsing/issues/43) */
 			if (local_default_namespace != NULL) {
@@ -1064,24 +1067,24 @@ static int dom_xml_serialize_element_node(
 			inherited_ns = ns;
 
 			/* 12.6.4. Append the value of qualified name to markup. */
-			TRY_OR_CLEANUP(dom_xml_output_qname(out, &qualified_name));
+			TRY_OR_CLEANUP(dom_xml_output_qname(ctx->out, &qualified_name));
 
 			/* 12.6.5. Append the following to markup, in the order listed: ... */
-			TRY_OR_CLEANUP(xmlOutputBufferWriteLit(out, " xmlns=\"")); /* 12.6.5.1 - 12.6.5.2 */
-			TRY_OR_CLEANUP(dom_xml_common_text_serialization(out, (const char *) ns, true));
-			TRY_OR_CLEANUP(xmlOutputBufferWriteLit(out, "\""));
+			TRY_OR_CLEANUP(xmlOutputBufferWriteLit(ctx->out, " xmlns=\"")); /* 12.6.5.1 - 12.6.5.2 */
+			TRY_OR_CLEANUP(dom_xml_common_text_serialization(ctx->out, (const char *) ns, true));
+			TRY_OR_CLEANUP(xmlOutputBufferWriteLit(ctx->out, "\""));
 		}
 		/* 12.7. Otherwise, the node has a local default namespace that matches ns ... */
 		else {
 			qualified_name.name = element->name;
 			inherited_ns = ns;
-			TRY_OR_CLEANUP(dom_xml_output_qname(out, &qualified_name));
+			TRY_OR_CLEANUP(dom_xml_output_qname(ctx->out, &qualified_name));
 		}
 	}
 
 	/* 13. Append to markup the result of the XML serialization of node's attributes given map, prefix index,
 	 *     local prefixes map, ignore namespace definition attribute flag, and require well-formed flag. */
-	TRY_OR_CLEANUP(dom_xml_serialize_attributes(out, element, &map, &local_prefixes_map, prefix_index, ignore_namespace_definition_attribute, require_well_formed));
+	TRY_OR_CLEANUP(dom_xml_serialize_attributes(ctx->out, element, &map, &local_prefixes_map, prefix_index, ignore_namespace_definition_attribute, require_well_formed));
 
 	/* 14. If ns is the HTML namespace, and the node's list of children is empty, and the node's localName matches
 	 *     any one of the following void elements: ... */
@@ -1109,19 +1112,19 @@ static int dom_xml_serialize_element_node(
 				|| dom_local_name_compare_ex(element, "source", strlen("source"), name_length)
 				|| dom_local_name_compare_ex(element, "track", strlen("track"), name_length)
 				|| dom_local_name_compare_ex(element, "wbr", strlen("wbr"), name_length)) {
-				TRY_OR_CLEANUP(xmlOutputBufferWriteLit(out, " /"));
+				TRY_OR_CLEANUP(xmlOutputBufferWriteLit(ctx->out, " /"));
 				skip_end_tag = true;
 			}
 		} else {
 			/* 15. If ns is not the HTML namespace, and the node's list of children is empty,
 			 *     then append "/" (U+002F SOLIDUS) to markup and set the skip end tag flag to true. */
-			TRY_OR_CLEANUP(xmlOutputBufferWriteLit(out, "/"));
+			TRY_OR_CLEANUP(xmlOutputBufferWriteLit(ctx->out, "/"));
 			skip_end_tag = true;
 		}
 	}
 
 	/* 16. Append ">" (U+003E GREATER-THAN SIGN) to markup. */
-	TRY_OR_CLEANUP(xmlOutputBufferWriteLit(out, ">"));
+	TRY_OR_CLEANUP(xmlOutputBufferWriteLit(ctx->out, ">"));
 
 	/* 17. If the value of skip end tag is true, then return the value of markup and skip the remaining steps. */
 	if (!skip_end_tag) {
@@ -1136,20 +1139,20 @@ static int dom_xml_serialize_element_node(
 		/* 19. Otherwise, append to markup the result of running the XML serialization algorithm on each of node's children. */
 		for (xmlNodePtr child = element->children; child != NULL; child = child->next) {
 			if (should_format) {
-				TRY_OR_CLEANUP(dom_xml_output_indents(out, indent));
+				TRY_OR_CLEANUP(dom_xml_output_indents(ctx->out, indent));
 			}
-			TRY_OR_CLEANUP(dom_xml_serialization_algorithm(ctxt, out, &map, child, inherited_ns, prefix_index, indent, require_well_formed));
+			TRY_OR_CLEANUP(dom_xml_serialization_algorithm(ctx, &map, child, inherited_ns, prefix_index, indent, require_well_formed));
 		}
 
 		if (should_format) {
 			indent--;
-			TRY_OR_CLEANUP(dom_xml_output_indents(out, indent));
+			TRY_OR_CLEANUP(dom_xml_output_indents(ctx->out, indent));
 		}
 
 		/* 20. Append the following to markup, in the order listed: */
-		TRY_OR_CLEANUP(xmlOutputBufferWriteLit(out, "</"));
-		TRY_OR_CLEANUP(dom_xml_output_qname(out, &qualified_name));
-		TRY_OR_CLEANUP(xmlOutputBufferWriteLit(out, ">"));
+		TRY_OR_CLEANUP(xmlOutputBufferWriteLit(ctx->out, "</"));
+		TRY_OR_CLEANUP(dom_xml_output_qname(ctx->out, &qualified_name));
+		TRY_OR_CLEANUP(xmlOutputBufferWriteLit(ctx->out, ">"));
 	}
 
 	/* 21. Return the value of markup.
@@ -1166,8 +1169,7 @@ static int dom_xml_serialize_element_node(
 
 /* https://w3c.github.io/DOM-Parsing/#xml-serializing-a-documentfragment-node */
 static int dom_xml_serializing_a_document_fragment_node(
-	xmlSaveCtxtPtr ctxt,
-	xmlOutputBufferPtr out,
+	dom_xml_serialize_ctx *ctx,
 	dom_xml_ns_prefix_map *namespace_prefix_map,
 	xmlNodePtr node,
 	const xmlChar *namespace,
@@ -1182,7 +1184,7 @@ static int dom_xml_serializing_a_document_fragment_node(
 	/* 2. For each child child of node, in tree order, run the XML serialization algorithm on the child ... */
 	xmlNodePtr child = node->children;
 	while (child != NULL) {
-		TRY(dom_xml_serialization_algorithm(ctxt, out, namespace_prefix_map, child, namespace, prefix_index, indent, require_well_formed));
+		TRY(dom_xml_serialization_algorithm(ctx, namespace_prefix_map, child, namespace, prefix_index, indent, require_well_formed));
 		child = child->next;
 	}
 
@@ -1193,8 +1195,7 @@ static int dom_xml_serializing_a_document_fragment_node(
 
 /* https://w3c.github.io/DOM-Parsing/#dfn-xml-serializing-a-document-node */
 static int dom_xml_serializing_a_document_node(
-	xmlSaveCtxtPtr ctxt,
-	xmlOutputBufferPtr out,
+	dom_xml_serialize_ctx *ctx,
 	dom_xml_ns_prefix_map *namespace_prefix_map,
 	xmlNodePtr node,
 	const xmlChar *namespace,
@@ -1210,16 +1211,16 @@ static int dom_xml_serializing_a_document_node(
 	node->children = NULL;
 
 	/* https://github.com/w3c/DOM-Parsing/issues/50 */
-	TRY(xmlOutputBufferFlush(out));
-	TRY(xmlSaveDoc(ctxt, (xmlDocPtr) node));
-	TRY(xmlSaveFlush(ctxt));
+	TRY(xmlOutputBufferFlush(ctx->out));
+	TRY(xmlSaveDoc(ctx->ctxt, (xmlDocPtr) node));
+	TRY(xmlSaveFlush(ctx->ctxt));
 
 	node->children = child;
 
 	/* 2. For each child child of node, in tree order, run the XML serialization algorithm on the child passing along the provided arguments,
 	 *    and append the result to serialized document. */
 	while (child != NULL) {
-		TRY(dom_xml_serialization_algorithm(ctxt, out, namespace_prefix_map, child, namespace, prefix_index, indent, require_well_formed));
+		TRY(dom_xml_serialization_algorithm(ctx, namespace_prefix_map, child, namespace, prefix_index, indent, require_well_formed));
 		child = child->next;
 	}
 
@@ -1230,8 +1231,7 @@ static int dom_xml_serializing_a_document_node(
 
 /* https://w3c.github.io/DOM-Parsing/#dfn-xml-serialization-algorithm */
 static int dom_xml_serialization_algorithm(
-	xmlSaveCtxtPtr ctxt,
-	xmlOutputBufferPtr out,
+	dom_xml_serialize_ctx *ctx,
 	dom_xml_ns_prefix_map *namespace_prefix_map,
 	xmlNodePtr node,
 	const xmlChar *namespace,
@@ -1243,36 +1243,36 @@ static int dom_xml_serialization_algorithm(
 	/* If node's interface is: */
 	switch (node->type) {
 		case XML_ELEMENT_NODE:
-			return dom_xml_serialize_element_node(ctxt, out, namespace, namespace_prefix_map, node, prefix_index, indent, require_well_formed);
+			return dom_xml_serialize_element_node(ctx, namespace, namespace_prefix_map, node, prefix_index, indent, require_well_formed);
 
 		case XML_DOCUMENT_FRAG_NODE:
-			return dom_xml_serializing_a_document_fragment_node(ctxt, out, namespace_prefix_map, node, namespace, prefix_index, indent, require_well_formed);
+			return dom_xml_serializing_a_document_fragment_node(ctx, namespace_prefix_map, node, namespace, prefix_index, indent, require_well_formed);
 
 		case XML_HTML_DOCUMENT_NODE:
 		case XML_DOCUMENT_NODE:
-			return dom_xml_serializing_a_document_node(ctxt, out, namespace_prefix_map, node, namespace, prefix_index, indent, require_well_formed);
+			return dom_xml_serializing_a_document_node(ctx, namespace_prefix_map, node, namespace, prefix_index, indent, require_well_formed);
 
 		case XML_TEXT_NODE:
-			return dom_xml_serialize_text_node(out, node, require_well_formed);
+			return dom_xml_serialize_text_node(ctx->out, node, require_well_formed);
 
 		case XML_COMMENT_NODE:
-			return dom_xml_serialize_comment_node(out, node, require_well_formed);
+			return dom_xml_serialize_comment_node(ctx->out, node, require_well_formed);
 
 		case XML_PI_NODE:
-			return dom_xml_serialize_processing_instruction(out, node, require_well_formed);
+			return dom_xml_serialize_processing_instruction(ctx->out, node, require_well_formed);
 
 		case XML_CDATA_SECTION_NODE:
-			return dom_xml_serialize_cdata_section_node(out, node);
+			return dom_xml_serialize_cdata_section_node(ctx->out, node);
 
 		case XML_ATTRIBUTE_NODE:
-			return dom_xml_serialize_attribute_node(out, node);
+			return dom_xml_serialize_attribute_node(ctx->out, node);
 
 		default:
-			TRY(xmlOutputBufferFlush(out));
-			TRY(xmlSaveTree(ctxt, node));
-			TRY(xmlSaveFlush(ctxt));
+			TRY(xmlOutputBufferFlush(ctx->out));
+			TRY(xmlSaveTree(ctx->ctxt, node));
+			TRY(xmlSaveFlush(ctx->ctxt));
 			if (node->type == XML_DTD_NODE) {
-				return xmlOutputBufferWriteLit(out, "\n");
+				return xmlOutputBufferWriteLit(ctx->out, "\n");
 			}
 			return 0;
 	}
@@ -1297,8 +1297,11 @@ int dom_xml_serialize(xmlSaveCtxtPtr ctxt, xmlOutputBufferPtr out, xmlNodePtr no
 	unsigned int prefix_index = 1;
 
 	/* 5. Return the result of running the XML serialization algorithm ... */
+	dom_xml_serialize_ctx ctx;
+	ctx.out = out;
+	ctx.ctxt = ctxt;
 	int indent = format ? 0 : -1;
-	int result = dom_xml_serialization_algorithm(ctxt, out, &namespace_prefix_map, node, namespace, &prefix_index, indent, require_well_formed);
+	int result = dom_xml_serialization_algorithm(&ctx, &namespace_prefix_map, node, namespace, &prefix_index, indent, require_well_formed);
 
 	dom_xml_ns_prefix_map_dtor(&namespace_prefix_map);