Enable syscall_test on windows.

tests/syscalls/syscalls.cc

 /*
  * Copyright (c) 2011 The Native Client Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 /*
  * NaCl tests for simple syscalls
  */
 
@@ skipping 156 matching lines @@
   char dirname[PATH_MAX] = { '\0' };
   char newdir[PATH_MAX] = { '\0' };
   char parent[PATH_MAX] = { '\0' };
 
   char *rtn = getcwd(dirname, PATH_MAX);
   ASSERT_EQ_MSG(rtn, dirname, "getcwd() failed to return dirname");
   ASSERT_NE_MSG(strlen(dirname), 0, "getcwd() failed to set valid dirname");
 
   // Calculate parent folder.
   strncpy(parent, dirname, PATH_MAX);
-  strrchr(parent, '/')[0] = '\0';
+  char *basename_start = strrchr(parent, '/');
+  if (basename_start == NULL) {
+    basename_start = strrchr(parent, '\\');
+    ASSERT_NE_MSG(basename_start, NULL, "test_file contains no dir seperator");
+  }
+  basename_start[0] = '\0';
 
   int retcode = chdir("..");
   ASSERT_EQ_MSG(retcode, 0, "chdir() failed");
 
   rtn = getcwd(newdir, PATH_MAX);
   ASSERT_EQ_MSG(rtn, newdir, "getcwd() failed");
 
   ASSERT_MSG(strcmp(newdir, parent) == 0, "getcwd() failed after chdir");
   retcode = chdir(dirname);
   ASSERT_EQ_MSG(retcode, 0, "chdir() failed");
@@ skipping 482 matching lines @@
   passed = testSuite(argv[1]);
 
   if (passed) {
     printf("All tests PASSED\n");
     exit(0);
   } else {
     printf("One or more tests FAILED\n");
     exit(-1);
   }
 }