[PATCH 1/4] strncmp: Add a testcase for page boundary [BZ #25933]

[H.J. Lu]

Add a strncmp testcase to cover cases where one of strings ends on the
page boundary.
---
 string/test-strncmp.c | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/string/test-strncmp.c b/string/test-strncmp.c
index d961ac4493..d0928a2864 100644
--- a/string/test-strncmp.c
+++ b/string/test-strncmp.c
@@ -403,6 +403,30 @@ check2 (void)
   free (s2);
 }
 
+static void
+check3 (void)
+{
+  size_t size = 32 * 4;
+  CHAR *s1 = (CHAR *) (buf1 + (BUF1PAGES - 1) * page_size);
+  CHAR *s2 = (CHAR *) (buf2 + (BUF1PAGES - 1) * page_size);
+  int exp_result;
+
+  memset (s1, 'a', page_size);
+  memset (s2, 'a', page_size);
+  s1[(page_size / CHARBYTES) - 1] = (CHAR) 0;
+
+  for (size_t s = 99; s <= size; s++)
+    for (size_t s1a = 31; s1a < 32; s1a++)
+      for (size_t s2a = 30; s2a < 32; s2a++)
+	{
+	  CHAR *s1p = s1 + (page_size / CHARBYTES - s) - s1a;
+	  CHAR *s2p = s2 + (page_size / CHARBYTES - s) - s2a;
+	  exp_result = SIMPLE_STRNCMP (s1p, s2p, s);
+	  FOR_EACH_IMPL (impl, 0)
+	    check_result (impl, s1p, s2p, s, exp_result);
+	}
+}
+
 int
 test_main (void)
 {
@@ -412,6 +436,7 @@ test_main (void)
 
   check1 ();
   check2 ();
+  check3 ();
 
   printf ("%23s", "");
   FOR_EACH_IMPL (impl, 0)
-- 
2.26.2