add getcwd test from glibc

test/unistd/tst-getcwd.c

@@ -0,0 +1,161 @@
+/* Test of getcwd function.
+   Copyright (C) 2000-2018 Free Software Foundation, Inc.
+
+   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 <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/param.h>
+
+
+#define TEST_FUNCTION do_test ()
+static int
+do_test (void)
+{
+  char thepath[4096];	/* Yes, this limits the environment this test
+			   can run it but I honestly don't care about
+			   people which have this problem.  */
+  char *bufs[10];
+  size_t lens[10];
+  size_t sbs;
+  size_t len, i;
+
+  if (getcwd (thepath, sizeof thepath) == NULL)
+    {
+      if (errno == ERANGE)
+	/* The path is too long, skip all tests.  */
+	return 0;
+
+      puts ("getcwd (thepath, sizeof thepath) failed");
+      return 1;
+    }
+  len = strlen (thepath);
+
+  sbs = 1;
+  while (sbs < len + 1)
+    sbs <<= 1;
+
+  for (i = 0; i < 4; ++i)
+    {
+      lens[i] = sbs;
+      bufs[i] = (char *) malloc (sbs);
+    }
+
+  bufs[i] = getcwd (NULL, sbs);
+  lens[i] = sbs;
+  if (bufs[i] == NULL)
+    {
+      puts ("getcwd (NULL, sbs) failed");
+      return 1;
+    }
+  ++i;
+
+  for (; i < 10; sbs >>= 1, ++i)
+    {
+      bufs[i] = (char *) malloc (MAX (1, sbs));
+      lens[i] = sbs;
+    }
+
+  /* Before we test the result write something in the memory to see
+     whether the allocation went right.  */
+  for (i = 0; i < 10; ++i)
+    if (i != 4 && bufs[i] != NULL)
+      memset (bufs[i], '\xff', lens[i]);
+
+  if (strcmp (thepath, bufs[4]) != 0)
+    {
+      printf ("\
+getcwd (NULL, sbs) = \"%s\", getcwd (thepath, sizeof thepath) = \"%s\"\n",
+	      bufs[4], thepath);
+      return 1;
+    }
+
+  /* Now overwrite all buffers to see that getcwd allocated the buffer
+     of right size.  */
+  for (i = 0; i < 10; ++i)
+    memset (bufs[i], i, lens[i]);
+
+  for (i = 0; i < 10; ++i)
+    free (bufs[i]);
+
+  /* Test whether the function signals success despite the buffer
+     being too small.  */
+  if (getcwd (NULL, len) != NULL)
+    {
+      puts ("getcwd (NULL, len) didn't failed");
+      return 1;
+    }
+
+  bufs[0] = malloc (len);
+  bufs[1] = malloc (len);
+  bufs[2] = malloc (len);
+  if (bufs[1] != NULL)
+    {
+      if (getcwd (bufs[1], len) != NULL)
+	{
+	  puts ("getcwd (bufs[1], len) didn't failed");
+	  return 1;
+	}
+      free (bufs[0]);
+      free (bufs[1]);
+      free (bufs[2]);
+    }
+
+  memset (thepath, '\xfe', sizeof (thepath));
+  if (getcwd (thepath, len) != NULL)
+    {
+      puts ("getcwd (thepath, len) didn't failed");
+      return 1;
+    }
+
+  for (i = len; i < sizeof thepath; ++i)
+    if (thepath[i] != '\xfe')
+      {
+	puts ("thepath[i] != '\xfe'");
+	return 1;
+      }
+
+  /* Now test handling of correctly sized buffers.  */
+  bufs[0] = getcwd (NULL, len + 1);
+  if (bufs[0] == NULL)
+    {
+      puts ("getcwd (NULL, len + 1) failed");
+      return 1;
+    }
+  free (bufs[0]);
+
+  memset (thepath, '\xff', sizeof thepath);
+  if (getcwd (thepath, len + 1) == NULL)
+    {
+      puts ("getcwd (thepath, len + 1) failed");
+      return 1;
+    }
+
+  for (i = len + 1; i < sizeof thepath; ++i)
+    if (thepath[i] != '\xff')
+      {
+	printf ("thepath[%zd] != '\xff'\n", i);
+	return 1;
+      }
+
+  puts ("everything OK");
+
+  return 0;
+}
+
+#include "../test-skeleton.c"