Do not translate the file open flags other than read/write.

chrome/nacl/nacl_ipc_adapter.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 "chrome/nacl/nacl_ipc_adapter.h"
 
 #include <limits.h>
 #include <string.h>
 
 #include "base/basictypes.h"
@@ skipping 78 matching lines @@
   funcs.SendMsg = NaClDescCustomSendMsg;
   funcs.RecvMsg = NaClDescCustomRecvMsg;
   // NaClDescMakeCustomDesc gives us a reference on the returned NaClDesc.
   return NaClDescMakeCustomDesc(new DescThunker(adapter), &funcs);
 }
 
 void DeleteChannel(IPC::Channel* channel) {
   delete channel;
 }
 
-int TranslatePepperFileOpenFlags(int32_t pp_open_flags) {
+// Translates Pepper's read/write open flags into NaCl's ones. The other open
+// flags are discarded. If neither of the read/write flags is specified, just
+// returns NACL_ABI_O_RDONLY as a safe fallback.
+int TranslatePepperFileReadWriteOpenFlags(int32_t pp_open_flags) {
   int nacl_open_flag;
-  switch (pp_open_flags & (PP_FILEOPENFLAG_READ | PP_FILEOPENFLAG_WRITE)) {
-    case PP_FILEOPENFLAG_READ:
-      nacl_open_flag = NACL_ABI_O_RDONLY;
-      break;
-    case PP_FILEOPENFLAG_WRITE:
-      nacl_open_flag = NACL_ABI_O_WRONLY;
-      break;
-    case PP_FILEOPENFLAG_READ | PP_FILEOPENFLAG_WRITE:
-      nacl_open_flag = NACL_ABI_O_RDWR;
-      break;
-    default:
-      // NACL_ABI_O_RDONLY == 0, so make this ambiguous case readonly as a safe
-      // fallback.
-      nacl_open_flag = NACL_ABI_O_RDONLY;
-      break;
+  if ((pp_open_flags & (PP_FILEOPENFLAG_READ | PP_FILEOPENFLAG_WRITE)) ==
+      (PP_FILEOPENFLAG_READ | PP_FILEOPENFLAG_WRITE)) {
+    nacl_open_flag = NACL_ABI_O_RDWR;
+  } else if (pp_open_flags & PP_FILEOPENFLAG_READ) {
+    nacl_open_flag = NACL_ABI_O_RDONLY;
+  } else if (pp_open_flags & PP_FILEOPENFLAG_WRITE) {
+    nacl_open_flag = NACL_ABI_O_WRONLY;
+  } else {
+    DLOG(WARNING) << "PP_FILEOPENFLAG_READ and/or PP_FILEOPENFLAG_WRITE "
+                  << "should be specified.";
+    // NACL_ABI_O_RDONLY == 0, so make this ambiguous case readonly as a safe
+    // fallback.
+    nacl_open_flag = NACL_ABI_O_RDONLY;
   }
-
-  if (pp_open_flags & PP_FILEOPENFLAG_CREATE)
-    nacl_open_flag |= NACL_ABI_O_CREAT;
-  if (pp_open_flags & PP_FILEOPENFLAG_TRUNCATE)
-    nacl_open_flag |= NACL_ABI_O_TRUNC;
-  if (pp_open_flags & PP_FILEOPENFLAG_EXCLUSIVE)
-    nacl_open_flag |= NACL_ABI_O_EXCL;
   return nacl_open_flag;
 }
 
 class NaClDescWrapper {
  public:
   explicit NaClDescWrapper(NaClDesc* desc): desc_(desc) {}
   ~NaClDescWrapper() {
     NaClDescUnref(desc_);
   }
 
@@ skipping 304 matching lines @@
                          base::Passed(&response)));
           break;
         }
         case ppapi::proxy::SerializedHandle::FILE:
           nacl_desc.reset(new NaClDescWrapper(NaClDescIoDescFromHandleAllocCtor(
 #if defined(OS_WIN)
               iter->descriptor(),
 #else
               iter->descriptor().fd,
 #endif
-              TranslatePepperFileOpenFlags(iter->open_flag()))));
+              TranslatePepperFileReadWriteOpenFlags(iter->open_flag()))));
           break;
         case ppapi::proxy::SerializedHandle::INVALID: {
           // Nothing to do. TODO(dmichael): Should we log this? Or is it
           // sometimes okay to pass an INVALID handle?
           break;
         }
         // No default, so the compiler will warn us if new types get added.
       }
       if (nacl_desc.get())
         rewritten_msg->AddDescriptor(nacl_desc.release());
@@ skipping 118 matching lines @@
 
   header.payload_size = static_cast<uint32>(msg.payload_size());
   header.routing = msg.routing_id();
   header.type = msg.type();
   header.flags = msg.flags();
   header.num_fds = static_cast<int>(rewritten_msg->desc_count());
 
   rewritten_msg->SetData(header, msg.payload(), msg.payload_size());
   locked_data_.to_be_received_.push(rewritten_msg);
 }
+
+int TranslatePepperFileReadWriteOpenFlagsForTesting(int32_t pp_open_flags) {
+  return TranslatePepperFileReadWriteOpenFlags(pp_open_flags);
+}