[NaCl SDK] nacl_io: Added support for access() syscall.

native_client_sdk/src/libraries/nacl_io/mount_dev.cc

 /* Copyright (c) 2012 The Chromium Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 #if defined(WIN32)
 #define _CRT_RAND_S
 #endif
 
 #include <errno.h>
 #include <fcntl.h>
 #include <string.h>
+#include <unistd.h>
 #include "nacl_io/kernel_wrap_real.h"
 #include "nacl_io/mount_dev.h"
 #include "nacl_io/mount_node.h"
 #include "nacl_io/mount_node_dir.h"
 #include "nacl_io/pepper_interface.h"
 #include "sdk_util/auto_lock.h"
 
 #if defined(__native_client__)
 #include <irt.h>
 #elif defined(WIN32)
@@ skipping 240 matching lines @@
 Error UrandomNode::Write(size_t offs,
                          const void* buf,
                          size_t count,
                          int* out_bytes) {
   *out_bytes = count;
   return 0;
 }
 
 }  // namespace
 
+Error MountDev::Access(const Path& path, int a_mode) {
+  MountNode* node = NULL;
+
+  AutoLock lock(&lock_);
+
+  int error = root_->FindChild(path.Join(), &node);
+  if (error)
+    return error;
+
+  // Don't allow execute access.
+  if (a_mode & X_OK)
+    return EACCES;
+
+  return 0;
+}
+
 Error MountDev::Open(const Path& path, int mode, MountNode** out_node) {
   *out_node = NULL;
 
   AutoLock lock(&lock_);
 
   // Don't allow creating any files.
   if (mode & O_CREAT)
     return EINVAL;
 
   MountNode* node = NULL;
@@ skipping 46 matching lines @@
   INITIALIZE_DEV_NODE_1("/stderr", RealNode, 2);
 
   return 0;
 }
 
 void MountDev::Destroy() {
   if (root_)
     root_->Release();
   root_ = NULL;
 }