Set file tokens for NaCl main nexe if available to enable validation caching.

ppapi/native_client/src/trusted/plugin/plugin.cc

Index: ppapi/native_client/src/trusted/plugin/plugin.cc
diff --git a/ppapi/native_client/src/trusted/plugin/plugin.cc b/ppapi/native_client/src/trusted/plugin/plugin.cc
index b516879d6f5d8a2914f175d9fc1807067b87cec5..3c316feb6284a8de827725b8b6f389004725bce9 100644
--- a/ppapi/native_client/src/trusted/plugin/plugin.cc
+++ b/ppapi/native_client/src/trusted/plugin/plugin.cc
@@ -23,6 +23,7 @@
 #include "native_client/src/include/portability.h"
 #include "native_client/src/include/portability_io.h"
 #include "native_client/src/include/portability_string.h"
+#include "native_client/src/public/nacl_file_info.h"
 #include "native_client/src/shared/platform/nacl_check.h"
 #include "native_client/src/trusted/desc/nacl_desc_wrapper.h"
 #include "native_client/src/trusted/nonnacl_util/sel_ldr_launcher.h"
@@ -375,6 +376,8 @@ Plugin::Plugin(PP_Instance pp_instance)
   // We call set_exit_status() here to ensure that the 'exitStatus' property is
   // set. This can only be called when nacl_interface_ is not NULL.
   set_exit_status(-1);
+  memset(&nexe_file_info_, 0, sizeof nexe_file_info_);
+  nexe_file_info_.desc = -1;
 }
 
 
@@ -446,11 +449,17 @@ void Plugin::NexeFileDidOpen(int32_t pp_error) {
   if (pp_error != PP_OK)
     return;
 
-  int32_t desc = ConvertFileDescriptor(nexe_handle_);
+  nexe_file_info_.desc = ConvertFileDescriptor(nexe_handle_);

[teravest, 2014/05/21 16:49:42]

I'm a little confused why nexe_file_info_ needs to be a class member; it might
be simpler to just create the NaClFileInfo inline in this function, and have
Plugin class members for token_lo and token_hi.

I have a similar change for dealing with files downloaded for open_resource():
https://codereview.chromium.org/294633003/

...and ended up making a PP_NaClFileInfo type that I passed around, which seemed
to work alright.

[jvoung (off chromium), 2014/05/21 21:10:56]

It was mostly to avoid heap allocating the NaClFileInfo, but yeah I can make the
members token_lo and token_hi instead and only reconstitute the NaClFileInfo
here.
Should I leave the ppb_nacl interface having separate desc/tokens for now, and
switch to PP_NaClFileInfo later?

   nexe_handle_ = PP_kInvalidFileHandle;  // Clear out nexe handle.
 
+  NaClDesc *desc = NaClDescIoFromFileInfo(nexe_file_info_, O_RDONLY);
+  if (desc == NULL)
+    return;
+  // nexe_file_info_ is handed to desc, clear out old copy.
+  memset(&nexe_file_info_, 0, sizeof nexe_file_info_);
+  nexe_file_info_.desc = -1;
   nacl::scoped_ptr<nacl::DescWrapper>
-      wrapper(wrapper_factory()->MakeFileDesc(desc, O_RDONLY));
+      wrapper(wrapper_factory()->MakeGenericCleanup(desc));
   NaClLog(4, "NexeFileDidOpen: invoking LoadNaClModule\n");
   LoadNaClModule(
       wrapper.release(),
@@ -574,6 +583,8 @@ void Plugin::ProcessNaClManifest(const nacl::string& manifest_json) {
       nacl_interface_->DownloadNexe(pp_instance(),
                                     program_url_.c_str(),
                                     &nexe_handle_,
+                                    &nexe_file_info_.file_token.lo,
+                                    &nexe_file_info_.file_token.hi,
                                     open_callback.pp_completion_callback());
       return;
     }