From: Philippe Proulx <eeppeliteloop@gmail.com>
Date: Tue, 14 Jul 2015 23:36:15 +0000 (-0400)
Subject: Fix: require power of two for type alignment
X-Git-Tag: v2.0.0-pre1~1212
X-Git-Url: http://git.efficios.com/?p=babeltrace.git;a=commitdiff_plain;h=9ad2f879463a33f00793d2f8c0f27ca227aca468

Fix: require power of two for type alignment

Signed-off-by: Philippe Proulx <eeppeliteloop@gmail.com>
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
---

diff --git a/formats/ctf/ir/event-types.c b/formats/ctf/ir/event-types.c
index df117474..da0ecd6d 100644
--- a/formats/ctf/ir/event-types.c
+++ b/formats/ctf/ir/event-types.c
@@ -1780,14 +1780,20 @@ end:
 	return ret;
 }
 
+static inline
+int is_power_of_two(unsigned int value)
+{
+	return ((value & (value - 1)) == 0) && value > 0;
+}
+
 int bt_ctf_field_type_set_alignment(struct bt_ctf_field_type *type,
 		unsigned int alignment)
 {
 	int ret = 0;
 	enum ctf_type_id type_id;
 
-	/* Alignment must be bit-aligned (1) or byte aligned */
-	if (!type || type->frozen || (alignment != 1 && (alignment & 0x7))) {
+	/* Alignment must be a power of two */
+	if (!type || type->frozen || !is_power_of_two(alignment)) {
 		ret = -1;
 		goto end;
 	}