dom/quota/ScopedLogExtraInfo.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
   5  * You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef DOM_QUOTA_SCOPEDLOGEXTRAINFO_H_
   8 #define DOM_QUOTA_SCOPEDLOGEXTRAINFO_H_
   9
  10 #include "mozilla/dom/quota/Config.h"
  11
  12 #include <map>
  13 #include "mozilla/Assertions.h"
  14 #include "mozilla/Attributes.h"
  15 #include "mozilla/ThreadLocal.h"
  16 #include "nsString.h"
  17 #include "nsXULAppAPI.h"
  18
  19 namespace mozilla::dom::quota {
  20
  21 struct MOZ_STACK_CLASS ScopedLogExtraInfo {
  22   static constexpr const char kTagQuery[] = "query";
  23   static constexpr const char kTagContext[] = "context";
  24
  25 #ifdef QM_SCOPED_LOG_EXTRA_INFO_ENABLED
  26  private:
  27   static auto FindSlot(const char* aTag);
  28
  29  public:
  30   template <size_t N>
  31   ScopedLogExtraInfo(const char (&aTag)[N], const nsACString& aExtraInfo)
  32       : mTag{aTag}, mCurrentValue{aExtraInfo} {
  33     // Initialize is currently only called in the parent process, we could call
  34     // it directly from nsLayoutStatics::Initialize in the content process to
  35     // allow use of ScopedLogExtraInfo in that too. The check in GetExtraInfoMap
  36     // must be removed then.
  37     MOZ_ASSERT(XRE_IsParentProcess());
  38
  39     AddInfo();
  40   }
  41
  42   ~ScopedLogExtraInfo();
  43
  44   ScopedLogExtraInfo(ScopedLogExtraInfo&& aOther);
  45   ScopedLogExtraInfo& operator=(ScopedLogExtraInfo&& aOther) = delete;
  46
  47   ScopedLogExtraInfo(const ScopedLogExtraInfo&) = delete;
  48   ScopedLogExtraInfo& operator=(const ScopedLogExtraInfo&) = delete;
  49
  50   using ScopedLogExtraInfoMap = std::map<const char*, const nsACString*>;
  51   static ScopedLogExtraInfoMap GetExtraInfoMap();
  52
  53   static void Initialize();
  54
  55  private:
  56   const char* mTag;
  57   const nsACString* mPreviousValue;
  58   nsCString mCurrentValue;
  59
  60   static MOZ_THREAD_LOCAL(const nsACString*) sQueryValue;
  61   static MOZ_THREAD_LOCAL(const nsACString*) sContextValue;
  62
  63   void AddInfo();
  64 #else
  65   template <size_t N>
  66   ScopedLogExtraInfo(const char (&aTag)[N], const nsACString& aExtraInfo) {}
  67
  68   // user-defined to silence unused variable warnings
  69   ~ScopedLogExtraInfo() {}
  70 #endif
  71 };
  72
  73 }  // namespace mozilla::dom::quota
  74
  75 #endif  // DOM_QUOTA_SCOPEDLOGEXTRAINFO_H_