Make a NaClDesc ctor for creating descs from NaClFileInfo.

src/trusted/desc/nacl_desc_wrapper.cc

 // Copyright (c) 2012 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.
 
 #include <limits>
 #include <new>
 #include "native_client/src/include/portability.h"
 #include "native_client/src/include/portability_string.h"
 #include "native_client/src/public/imc_types.h"
 #include "native_client/src/shared/imc/nacl_imc_c.h"
@@ skipping 297 matching lines @@
 }
 
 DescWrapper* DescWrapperFactory::MakeFileDesc(int host_os_desc, int mode) {
   struct NaClDesc* desc = ImportHostDescCommon(host_os_desc, mode);
   if (NULL == desc) {
     return NULL;
   }
   return MakeGenericCleanup(desc);
 }
 
+DescWrapper* DescWrapperFactory::MakeFileDescMetadata(struct NaClFileInfo info,
+                                                      int mode) {
+  int error;
+  struct NaClDesc* desc = ImportHostDescCommon(info.desc, mode);
+  if (NULL == desc) {
+    return NULL;
+  }
+  if (info.file_token.lo != 0 || info.file_token.hi != 0) {

[Nick Bray (chromium), 2014/05/02 19:44:35]

See previous CLs for comments on this check.

[jvoung (off chromium), 2014/05/02 20:38:23]

Done.

+    error = (*NACL_VTBL(NaClDesc, desc)->

[Nick Bray (chromium), 2014/05/02 19:44:35]

Why no NaClDescSetFileToken?

[jvoung (off chromium), 2014/05/02 20:38:23]

That's part of desc_cacheabiilty/ and desc_cacheability/ depends on desc/, so I
didn't want to make desc/ depend on desc_cacheability too.

I've moved those helpers over to desc/ and reused them.

+             SetMetadata)(desc,
+                          NACL_DESC_METADATA_FILE_TOKEN_TYPE,
+                          sizeof info.file_token,
+                          (uint8_t const *) &info.file_token);
+    if (0 != error) {
+      NaClDescSafeUnref(desc);
+      return NULL;
+    }
+  }
+  return MakeGenericCleanup(desc);
+}
+
 DescWrapper* DescWrapperFactory::MakeFileDescQuota(int host_os_desc,
                                                    int mode,
                                                    const uint8_t* file_id) {
   struct NaClDesc* desc = ImportHostDescCommon(host_os_desc, mode);
   if (NULL == desc) {
     return NULL;
   }
   struct NaClDesc* desc_quota = MakeQuotaCommon(file_id, desc);
   if (desc_quota == NULL) {
     NaClDescSafeUnref(desc);
@@ skipping 302 matching lines @@
   return reinterpret_cast<struct NaClDescVtbl const *>(desc_->base.vtbl)->
       SemWait(desc_);
 }
 
 int DescWrapper::GetValue() {
   return reinterpret_cast<struct NaClDescVtbl const *>(desc_->base.vtbl)->
       GetValue(desc_);
 }
 
 }  // namespace nacl