libnm: add nm_utils_uuid_generate_buf() util

2 files changed, 25 insertions, 7 deletions

diff --git a/libnm-core/nm-core-internal.h b/libnm-core/nm-core-internal.h
index 8fba357167..1b4c469420 100644
--- a/libnm-core/nm-core-internal.h
+++ b/libnm-core/nm-core-internal.h
@@ -194,6 +194,14 @@ char *nm_utils_uuid_generate_from_string (const char *s, gssize slen, int uuid_t
 
 char *_nm_utils_uuid_generate_from_strings (const char *string1, ...) G_GNUC_NULL_TERMINATED;
 
+char *nm_utils_uuid_generate_buf_ (char *buf);
+#define nm_utils_uuid_generate_buf(buf) \
+	({ \
+		G_STATIC_ASSERT (sizeof (buf) == G_N_ELEMENTS (buf) && sizeof (buf) >= 37); \
+		nm_utils_uuid_generate_buf_ (buf); \
+	})
+#define nm_utils_uuid_generate_a() (nm_utils_uuid_generate_buf_ (g_alloca (37)))
+
 void _nm_dbus_errors_init (void);
 
 extern gboolean _nm_utils_is_manager_process;
diff --git a/libnm-core/nm-utils.c b/libnm-core/nm-utils.c
index cfd97149ca..41b6304c82 100644
--- a/libnm-core/nm-utils.c
+++ b/libnm-core/nm-utils.c
@@ -2147,24 +2147,34 @@ next:
 /*****************************************************************************/
 
 /**
- * nm_utils_uuid_generate:
+ * nm_utils_uuid_generate_buf_:
+ * @buf: input buffer, must contain at least 37 bytes
  *
- * Returns: a newly allocated UUID suitable for use as the #NMSettingConnection
- * object's #NMSettingConnection:id: property.  Should be freed with g_free()
+ * Returns: generates a new random UUID, writes it to @buf and returns @buf.
  **/
 char *
-nm_utils_uuid_generate (void)
+nm_utils_uuid_generate_buf_ (char *buf)
 {
 	uuid_t uuid;
-	char *buf;
 
-	buf = g_malloc0 (37);
 	uuid_generate_random (uuid);
-	uuid_unparse_lower (uuid, &buf[0]);
+	uuid_unparse_lower (uuid, buf);
 	return buf;
 }
 
 /**
+ * nm_utils_uuid_generate:
+ *
+ * Returns: a newly allocated UUID suitable for use as the #NMSettingConnection
+ * object's #NMSettingConnection:id: property.  Should be freed with g_free()
+ **/
+char *
+nm_utils_uuid_generate (void)
+{
+	return nm_utils_uuid_generate_buf_ (g_malloc (37));
+}
+
+/**
  * nm_utils_uuid_generate_from_string:
  * @s: a string to use as the seed for the UUID
  * @slen: if negative, treat @s as zero terminated C string.