diff --git a/ap/libc/glibc/glibc-2.23/string/test-strcasecmp.c b/ap/libc/glibc/glibc-2.23/string/test-strcasecmp.c
new file mode 100644
index 0000000..63ae2a2
--- /dev/null
+++ b/ap/libc/glibc/glibc-2.23/string/test-strcasecmp.c
@@ -0,0 +1,270 @@
+/* Test and measure strcasecmp functions.
+   Copyright (C) 1999-2016 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Written by Jakub Jelinek <jakub@redhat.com>, 1999.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <locale.h>
+#include <ctype.h>
+#define TEST_MAIN
+#define TEST_NAME "strcasecmp"
+#include "test-string.h"
+
+typedef int (*proto_t) (const char *, const char *);
+static int simple_strcasecmp (const char *, const char *);
+static int stupid_strcasecmp (const char *, const char *);
+
+IMPL (stupid_strcasecmp, 0)
+IMPL (simple_strcasecmp, 0)
+IMPL (strcasecmp, 1)
+
+static int
+simple_strcasecmp (const char *s1, const char *s2)
+{
+  int ret;
+
+  while ((ret = ((unsigned char) tolower (*s1)
+		 - (unsigned char) tolower (*s2))) == 0
+	 && *s1++)
+    ++s2;
+  return ret;
+}
+
+static int
+stupid_strcasecmp (const char *s1, const char *s2)
+{
+  size_t ns1 = strlen (s1) + 1, ns2 = strlen (s2) + 1;
+  size_t n = ns1 < ns2 ? ns1 : ns2;
+  int ret = 0;
+
+  while (n--)
+    {
+      if ((ret = ((unsigned char) tolower (*s1)
+		  - (unsigned char) tolower (*s2))) != 0)
+	break;
+      ++s1;
+      ++s2;
+    }
+  return ret;
+}
+
+static void
+do_one_test (impl_t *impl, const char *s1, const char *s2, int exp_result)
+{
+  int result = CALL (impl, s1, s2);
+  if ((exp_result == 0 && result != 0)
+      || (exp_result < 0 && result >= 0)
+      || (exp_result > 0 && result <= 0))
+    {
+      error (0, 0, "Wrong result in function %s %d %d", impl->name,
+	     result, exp_result);
+      ret = 1;
+      return;
+    }
+}
+
+static void
+do_test (size_t align1, size_t align2, size_t len, int max_char,
+	 int exp_result)
+{
+  size_t i;
+  char *s1, *s2;
+
+  if (len == 0)
+    return;
+
+  align1 &= 7;
+  if (align1 + len + 1 >= page_size)
+    return;
+
+  align2 &= 7;
+  if (align2 + len + 1 >= page_size)
+    return;
+
+  s1 = (char *) (buf1 + align1);
+  s2 = (char *) (buf2 + align2);
+
+  for (i = 0; i < len; i++)
+    {
+      s1[i] = toupper (1 + 23 * i % max_char);
+      s2[i] = tolower (s1[i]);
+    }
+
+  s1[len] = s2[len] = 0;
+  s1[len + 1] = 23;
+  s2[len + 1] = 24 + exp_result;
+  if ((s2[len - 1] == 'z' && exp_result == -1)
+      || (s2[len - 1] == 'a' && exp_result == 1))
+    s1[len - 1] += exp_result;
+  else
+    s2[len - 1] -= exp_result;
+
+  FOR_EACH_IMPL (impl, 0)
+    do_one_test (impl, s1, s2, exp_result);
+}
+
+static void
+do_random_tests (void)
+{
+  size_t i, j, n, align1, align2, pos, len1, len2;
+  int result;
+  long r;
+  unsigned char *p1 = buf1 + page_size - 512;
+  unsigned char *p2 = buf2 + page_size - 512;
+
+  for (n = 0; n < ITERATIONS; n++)
+    {
+      align1 = random () & 31;
+      if (random () & 1)
+	align2 = random () & 31;
+      else
+	align2 = align1 + (random () & 24);
+      pos = random () & 511;
+      j = align1 > align2 ? align1 : align2;
+      if (pos + j >= 511)
+	pos = 510 - j - (random () & 7);
+      len1 = random () & 511;
+      if (pos >= len1 && (random () & 1))
+	len1 = pos + (random () & 7);
+      if (len1 + j >= 512)
+	len1 = 511 - j - (random () & 7);
+      if (pos >= len1)
+	len2 = len1;
+      else
+	len2 = len1 + (len1 != 511 - j ? random () % (511 - j - len1) : 0);
+      j = (pos > len2 ? pos : len2) + align1 + 64;
+      if (j > 512)
+	j = 512;
+      for (i = 0; i < j; ++i)
+	{
+	  p1[i] = tolower (random () & 255);
+	  if (i < len1 + align1 && !p1[i])
+	    {
+	      p1[i] = tolower (random () & 255);
+	      if (!p1[i])
+		p1[i] = tolower (1 + (random () & 127));
+	    }
+	}
+      for (i = 0; i < j; ++i)
+	{
+	  p2[i] = toupper (random () & 255);
+	  if (i < len2 + align2 && !p2[i])
+	    {
+	      p2[i] = toupper (random () & 255);
+	      if (!p2[i])
+		toupper (p2[i] = 1 + (random () & 127));
+	    }
+	}
+
+      result = 0;
+      memcpy (p2 + align2, p1 + align1, pos);
+      if (pos < len1)
+	{
+	  if (tolower (p2[align2 + pos]) == p1[align1 + pos])
+	    {
+	      p2[align2 + pos] = toupper (random () & 255);
+	      if (tolower (p2[align2 + pos]) == p1[align1 + pos])
+		p2[align2 + pos] = toupper (p1[align1 + pos]
+					    + 3 + (random () & 127));
+	    }
+
+	  if (p1[align1 + pos] < tolower (p2[align2 + pos]))
+	    result = -1;
+	  else
+	    result = 1;
+	}
+      p1[len1 + align1] = 0;
+      p2[len2 + align2] = 0;
+
+      FOR_EACH_IMPL (impl, 1)
+	{
+	  r = CALL (impl, (char *) (p1 + align1), (char *) (p2 + align2));
+	  /* Test whether on 64-bit architectures where ABI requires
+	     callee to promote has the promotion been done.  */
+	  asm ("" : "=g" (r) : "0" (r));
+	  if ((r == 0 && result)
+	      || (r < 0 && result >= 0)
+	      || (r > 0 && result <= 0))
+	    {
+	      error (0, 0, "Iteration %zd - wrong result in function %s (%zd, %zd, %zd, %zd, %zd) %ld != %d, p1 %p p2 %p",
+		     n, impl->name, align1, align2, len1, len2, pos, r, result, p1, p2);
+	      ret = 1;
+	    }
+	}
+    }
+}
+
+static void
+test_locale (const char *locale)
+{
+  size_t i;
+
+  if (setlocale (LC_CTYPE, locale) == NULL)
+    {
+      error (0, 0, "cannot set locale \"%s\"", locale);
+      ret = 1;
+    }
+
+  printf ("%-23s", locale);
+  FOR_EACH_IMPL (impl, 0)
+    printf ("\t%s", impl->name);
+  putchar ('\n');
+
+  for (i = 1; i < 16; ++i)
+    {
+      do_test (i, i, i, 127, 0);
+      do_test (i, i, i, 127, 1);
+      do_test (i, i, i, 127, -1);
+    }
+
+  for (i = 1; i < 10; ++i)
+    {
+      do_test (0, 0, 2 << i, 127, 0);
+      do_test (0, 0, 2 << i, 254, 0);
+      do_test (0, 0, 2 << i, 127, 1);
+      do_test (0, 0, 2 << i, 254, 1);
+      do_test (0, 0, 2 << i, 127, -1);
+      do_test (0, 0, 2 << i, 254, -1);
+    }
+
+  for (i = 1; i < 8; ++i)
+    {
+      do_test (i, 2 * i, 8 << i, 127, 0);
+      do_test (2 * i, i, 8 << i, 254, 0);
+      do_test (i, 2 * i, 8 << i, 127, 1);
+      do_test (2 * i, i, 8 << i, 254, 1);
+      do_test (i, 2 * i, 8 << i, 127, -1);
+      do_test (2 * i, i, 8 << i, 254, -1);
+    }
+
+  do_random_tests ();
+}
+
+int
+test_main (void)
+{
+  test_init ();
+
+  test_locale ("C");
+  test_locale ("en_US.ISO-8859-1");
+  test_locale ("en_US.UTF-8");
+  test_locale ("tr_TR.ISO-8859-9");
+  test_locale ("tr_TR.UTF-8");
+
+  return ret;
+}
+
+#include "../test-skeleton.c"