From 192ac21a3c057c5dedca4cdd1bf700f38992030c Mon Sep 17 00:00:00 2001

Message-Id: <192ac21a3c057c5dedca4cdd1bf700f38992030c.1496667760.git.jstancek@redhat.com>

From: Jan Stancek <jstancek@redhat.com>

Date: Thu, 1 Jun 2017 09:48:41 +0200

Subject: [PATCH v2 1/2] testutils: fix range_is_mapped()

It doesn't return correct value when tested region is

completely inside existing mapping:

  +--------------------------------------+

  ^ start                                ^ end

           +----------------+

           ^ low            ^ high

Rather than testing for all combinations of 2 regions overlapping,

flip the condition and test if they don't overlap.

Signed-off-by: Jan Stancek <jstancek@redhat.com>

---

 tests/testutils.c | 22 ++++++++++++++++------

 1 file changed, 16 insertions(+), 6 deletions(-)

This is a v2 series for:

  https://groups.google.com/forum/#!topic/libhugetlbfs/tAsWjuJ7x8k

diff --git a/tests/testutils.c b/tests/testutils.c

index 629837045465..f42852e1938b 100644

--- a/tests/testutils.c

+++ b/tests/testutils.c

@@ -190,19 +190,29 @@ int range_is_mapped(unsigned long low, unsigned long high)

 			return -1;

 		}

-		if ((start >= low) && (start < high)) {

+		/*

+		 * (existing mapping)    (tested region)

+		 * +----------------+      +.......+

+		 * ^start           ^end   ^ low   ^high

+		 */

+		if (low >= end) {

 			fclose(f);

-			return 1;

+			return 0;

 		}

-		if ((end >= low) && (end < high)) {

+

+		/*

+		 * (tested region)  (existing mapping)

+		 *     +.....+      +----------------+

+		 *     ^low  ^high  ^ start          ^end

+		 */

+		if (high <= start) {

 			fclose(f);

-			return 1;

+			return 0;

 		}

-

 	}

 	fclose(f);

-	return 0;

+	return 1;

 }

 /*

-- 

1.8.3.1