trivial: Add as_ref_string_debug()

This allows us to debug the reference counted string functionality.

3 files changed, 119 insertions, 0 deletions

diff --git a/client/as-util.c b/client/as-util.c
index f3f6a2c..87bd77f 100644
--- a/client/as-util.c
+++ b/client/as-util.c
@@ -1362,6 +1362,13 @@ as_util_search (AsUtilPrivate *priv, gchar **values, GError **error)
 		g_print ("%s\n", xml->str);
 	}
 
+	/* dump refcounted string debug data */
+	if (g_getenv ("AS_REF_STR_DEBUG") != NULL) {
+		g_autofree gchar *tmp = as_ref_string_debug (AS_REF_STRING_DEBUG_DEDUPED |
+							     AS_REF_STRING_DEBUG_DUPES);
+		g_print ("%s", tmp);
+	}
+
 	return TRUE;
 }
 
diff --git a/libappstream-glib/as-ref-string.c b/libappstream-glib/as-ref-string.c
index 1ee6376..a1ba129 100644
--- a/libappstream-glib/as-ref-string.c
+++ b/libappstream-glib/as-ref-string.c
@@ -261,3 +261,98 @@ as_ref_string_assign_safe (AsRefString **rstr_ptr, const gchar *str)
 	if (str != NULL)
 		*rstr_ptr = as_ref_string_new (str);
 }
+
+static gint
+as_ref_string_sort_by_refcnt_cb (gconstpointer a, gconstpointer b)
+{
+	AsRefStringHeader *hdr1 = AS_REFPTR_TO_HEADER (a);
+	AsRefStringHeader *hdr2 = AS_REFPTR_TO_HEADER (b);
+	if (hdr1->refcnt > hdr2->refcnt)
+		return -1;
+	if (hdr1->refcnt < hdr2->refcnt)
+		return 1;
+	return 0;
+}
+
+/**
+ * as_ref_string_debug:
+ * @flags: some #AsRefStringDebugFlags, e.g. %AS_REF_STRING_DEBUG_DUPES
+ *
+ * This function outputs some debugging information to a string.
+ *
+ * Returns: a string describing the current state of the dedupe hash.
+ *
+ * Since: 0.6.6
+ */
+gchar *
+as_ref_string_debug (AsRefStringDebugFlags flags)
+{
+	GHashTable *hash = as_ref_string_get_hash ();
+	GString *tmp = g_string_new (NULL);
+
+	/* overview */
+	g_string_append_printf (tmp, "Size of hash table: %u\n",
+				g_hash_table_size (hash));
+
+	/* success: deduped */
+	if (flags & AS_REF_STRING_DEBUG_DEDUPED) {
+		GList *l;
+		g_autoptr(GList) keys = g_hash_table_get_keys (hash);
+
+		/* split up sections */
+		if (tmp->len > 0)
+			g_string_append (tmp, "\n\n");
+
+		/* sort by refcount number */
+		keys = g_list_sort (keys, as_ref_string_sort_by_refcnt_cb);
+		g_string_append (tmp, "Deduplicated strings:\n");
+		for (l = keys; l != NULL; l = l->next) {
+			const gchar *str = l->data;
+			AsRefStringHeader *hdr = AS_REFPTR_TO_HEADER (str);
+			if (hdr->refcnt <= 1)
+				continue;
+			g_string_append_printf (tmp, "%i\t%s\n", hdr->refcnt, str);
+		}
+	}
+
+	/* failed: duplicate */
+	if (flags & AS_REF_STRING_DEBUG_DUPES) {
+		GList *l;
+		GList *l2;
+		g_autoptr(GHashTable) dupes = g_hash_table_new (g_direct_hash, g_direct_equal);
+		g_autoptr(GList) keys = g_hash_table_get_keys (hash);
+
+		/* split up sections */
+		if (tmp->len > 0)
+			g_string_append (tmp, "\n\n");
+
+		g_string_append (tmp, "Duplicated strings:\n");
+		for (l = keys; l != NULL; l = l->next) {
+			const gchar *str = l->data;
+			AsRefStringHeader *hdr = AS_REFPTR_TO_HEADER (str);
+			guint dupe_cnt = 0;
+
+			if (g_hash_table_contains (dupes, hdr))
+				continue;
+			g_hash_table_add (dupes, (gpointer) hdr);
+
+			for (l2 = l; l2 != NULL; l2 = l2->next) {
+				const gchar *str2 = l2->data;
+				AsRefStringHeader *hdr2 = AS_REFPTR_TO_HEADER (str2);
+				if (g_hash_table_contains (dupes, hdr2))
+					continue;
+				if (l == l2)
+					continue;
+				if (g_strcmp0 (str, str2) != 0)
+					continue;
+				g_hash_table_add (dupes, (gpointer) hdr2);
+				dupe_cnt += 1;
+			}
+			if (dupe_cnt > 0) {
+				g_string_append_printf (tmp, "%u\t%s\n",
+							dupe_cnt, str);
+			}
+		}
+	}
+	return g_string_free (tmp, FALSE);
+}
diff --git a/libappstream-glib/as-ref-string.h b/libappstream-glib/as-ref-string.h
index 2da3b08..79f26d9 100644
--- a/libappstream-glib/as-ref-string.h
+++ b/libappstream-glib/as-ref-string.h
@@ -32,6 +32,22 @@ G_BEGIN_DECLS
 
 typedef gchar AsRefString;
 
+/**
+ * AsRefStringDebugFlags:
+ * @AS_REF_STRING_DEBUG_NONE:			No detailed debugging
+ * @AS_REF_STRING_DEBUG_DEDUPED:		Show detailed dedupe stats
+ * @AS_REF_STRING_DEBUG_DUPES:			Show detailed duplication stats
+ *
+ * The debug type flags.
+ **/
+typedef enum {
+	AS_REF_STRING_DEBUG_NONE	= 0,		/* Since: 0.6.16 */
+	AS_REF_STRING_DEBUG_DEDUPED	= 1 << 0,	/* Since: 0.6.16 */
+	AS_REF_STRING_DEBUG_DUPES	= 1 << 1,	/* Since: 0.6.16 */
+	/*< private >*/
+	AS_REF_STRING_DEBUG_LAST
+} AsRefStringDebugFlags;
+
 AsRefString	*as_ref_string_new			(const gchar	*str);
 AsRefString	*as_ref_string_new_with_length		(const gchar	*str,
 							 gsize		 len);
@@ -44,6 +60,7 @@ void		 as_ref_string_assign			(AsRefString	**rstr_ptr,
 							 AsRefString	*rstr);
 void		 as_ref_string_assign_safe		(AsRefString	**rstr_ptr,
 							 const gchar	*str);
+gchar		*as_ref_string_debug			(AsRefStringDebugFlags flags);
 
 G_DEFINE_AUTOPTR_CLEANUP_FUNC(AsRefString, as_ref_string_unref)