dom/workers/Principal.cpp

   1 /* -*- Mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; tab-width: 40 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #include "Principal.h"
   7
   8 #include "jsapi.h"
   9 #include "mozilla/Assertions.h"
  10
  11 BEGIN_WORKERS_NAMESPACE
  12
  13 JSPrincipals*
  14 GetWorkerPrincipal()
  15 {
  16   static JSPrincipals sPrincipal;
  17
  18   /*
  19    * To make sure the the principals refcount is initialized to one, atomically
  20    * increment it on every pass though this function. If we discover this wasn't
  21    * the first time, decrement it again. This avoids the need for
  22    * synchronization.
  23    */
  24   int32_t prevRefcount = sPrincipal.refcount++;
  25   if (prevRefcount > 0) {
  26     --sPrincipal.refcount;
  27   } else {
  28 #ifdef DEBUG
  29     sPrincipal.debugToken = kJSPrincipalsDebugToken;
  30 #endif
  31   }
  32
  33   return &sPrincipal;
  34 }
  35
  36 void
  37 DestroyWorkerPrincipals(JSPrincipals* aPrincipals)
  38 {
  39   MOZ_ASSERT_UNREACHABLE("Worker principals refcount should never fall below one");
  40 }
  41
  42 END_WORKERS_NAMESPACE