3 files changed, 23 insertions, 6 deletions
diff --git a/content/content.c b/content/content.c
index 87dcfa226..4641571bd 100644
--- a/content/content.c
+++ b/content/content.c
@@ -860,14 +860,17 @@ void content_search_clear(struct hlcache_handle *h)
 	}
 }
 
-
-void content_debug_dump(struct hlcache_handle *h, FILE *f)
+/* exported interface documented in content/content.h */
+nserror content_debug_dump(struct hlcache_handle *h, FILE *f, enum content_debug op)
 {
 	struct content *c = hlcache_handle_get_content(h);
 	assert(c != 0);
 
-	if (c->handler->debug_dump != NULL)
-		c->handler->debug_dump(c, f);
+	if (c->handler->debug_dump == NULL) {
+		return NSERROR_NOT_IMPLEMENTED;
+	}
+
+	return c->handler->debug_dump(c, f, op);
 }
 
 
diff --git a/content/content.h b/content/content.h
index a2d07926c..752370034 100644
--- a/content/content.h
+++ b/content/content.h
@@ -87,6 +87,12 @@ typedef enum {
 	CONTENT_MSG_GADGETCLICK/**< A gadget has been clicked on (mainly for file) */
 } content_msg;
 
+/** Debugging dump operations */
+enum content_debug {
+	CONTENT_DEBUG_RENDER, /** Debug the contents rendering. */
+	CONTENT_DEBUG_DOM     /** Debug teh contents Document Object. */
+};
+
 /** RFC5988 metadata link */
 struct content_rfc5988_link {
 	struct content_rfc5988_link *next; /**< next rfc5988_link in list */
@@ -271,7 +277,15 @@ void content_search(struct hlcache_handle *h, void *context,
 		search_flags_t flags, const char *string);
 void content_search_clear(struct hlcache_handle *h);
 
-void content_debug_dump(struct hlcache_handle *h, FILE *f);
+/**
+ * Dump debug information to file.
+ *
+ * \param h content handle to debug.
+ * \param f File to write output to.
+ * \param op Debug operation type.
+ */
+nserror content_debug_dump(struct hlcache_handle *h, FILE *f, enum content_debug op);
+
 struct content_rfc5988_link *content_find_rfc5988_link(struct hlcache_handle *c,
 		lwc_string *rel);
 
diff --git a/content/content_protected.h b/content/content_protected.h
index f5448c803..7d51e1b8c 100644
--- a/content/content_protected.h
+++ b/content/content_protected.h
@@ -76,7 +76,7 @@ struct content_handler {
 	void (*search)(struct content *c, void *context, search_flags_t flags,
 		       const char *string);
 	void (*search_clear)(struct content *c);
-	void (*debug_dump)(struct content *c, FILE *f);
+	nserror (*debug_dump)(struct content *c, FILE *f, enum content_debug op);
 	nserror (*clone)(const struct content *old, struct content **newc);
 	bool (*matches_quirks)(const struct content *c, bool quirks);
 	content_type (*type)(void);