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

native_client_sdk/src/libraries/nacl_io/mount_http.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.
  */
 
 #include "nacl_io/mount_http.h"
 
 #include <assert.h>
 #include <ctype.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <stdio.h>
 #include <string.h>
 #include <sys/stat.h>
 #include <sys/types.h>
+#include <unistd.h>
 
 #include <vector>
 
 #include <ppapi/c/pp_errors.h>
 
 #include "nacl_io/mount_node_dir.h"
 #include "nacl_io/mount_node_http.h"
 #include "nacl_io/osinttypes.h"
 #include "sdk_util/auto_lock.h"
 
@@ skipping 21 matching lines @@
   bool upper = true;
   for (size_t i = 0; i < s.length(); ++i) {
     char c = s[i];
     result += upper ? toupper(c) : tolower(c);
     upper = c == '-';
   }
 
   return result;
 }
 
+Error MountHttp::Access(const Path& path, int a_mode) {
+  assert(url_root_.empty() || url_root_[url_root_.length() - 1] == '/');
+
+  NodeMap_t::iterator iter = node_cache_.find(path.Join());
+  if (iter == node_cache_.end()) {
+    // If we can't find the node in the cache, fetch it
+    std::string url = MakeUrl(path);
+    MountNodeHttp* node = new MountNodeHttp(this, url, cache_content_);
+    Error error = node->Init(O_RDONLY);
+    if (error) {
+      node->Release();
+      return error;
+    }
+
+    error = node->GetStat(NULL);
+    node->Release();
+    if (error)
+      return error;
+  }
+
+  // Don't allow write or execute access.
+  if (a_mode & (W_OK | X_OK))
+    return EACCES;
+
+  return 0;
+}
+
 Error MountHttp::Open(const Path& path, int mode, MountNode** out_node) {
   *out_node = NULL;
 
   assert(url_root_.empty() || url_root_[url_root_.length() - 1] == '/');
 
   NodeMap_t::iterator iter = node_cache_.find(path.Join());
   if (iter != node_cache_.end()) {
     *out_node = iter->second;
     return 0;
   }
 
   // If we can't find the node in the cache, create it
-  std::string url = url_root_ + (path.IsAbsolute() ? path.Range(1, path.Size())
-                                                   : path.Join());
-
+  std::string url = MakeUrl(path);
   MountNodeHttp* node = new MountNodeHttp(this, url, cache_content_);
   Error error = node->Init(mode);
   if (error) {
     node->Release();
     return error;
   }
 
   error = node->GetStat(NULL);
   if (error) {
     node->Release();
@@ skipping 248 matching lines @@
           break;
         case 'w':
           mode |= S_IWRITE;
           break;
         default:
           fprintf(stderr, "Unable to parse write %s for %s.\n", modestr, name);
           return EINVAL;
       }
 
       Path path(name);
-      std::string url =
-          url_root_ +
-          (path.IsAbsolute() ? path.Range(1, path.Size()) : path.Join());
-
+      std::string url = MakeUrl(path);
       MountNodeHttp* node = new MountNodeHttp(this, url, cache_content_);
       Error error = node->Init(mode);
       if (error) {
         node->Release();
         return error;
       }
 
       node->SetCachedSize(atoi(lenstr));
 
       MountNodeDir* dir_node;
@@ skipping 41 matching lines @@
     manifest_node->Release();
     return error;
   }
 
   manifest_node->Release();
   text[len] = 0;
 
   *out_manifest = text;
   return 0;
 }
+
+std::string MountHttp::MakeUrl(const Path& path) {
+  return url_root_ +
+         (path.IsAbsolute() ? path.Range(1, path.Size()) : path.Join());
+}