toolkit/xre/Bootstrap.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   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 /**
   7  * This file represents the only external interface exposed from libxul. It
   8  * is used by the various stub binaries (nsBrowserApp, xpcshell,
   9  * plugin-container) to initialize XPCOM and start their main loop.
  10  */
  11
  12 #ifndef mozilla_Bootstrap_h
  13 #define mozilla_Bootstrap_h
  14
  15 #include "mozilla/Maybe.h"
  16 #include "mozilla/ResultVariant.h"
  17 #include "mozilla/UniquePtr.h"
  18 #include "mozilla/UniquePtrExtensions.h"
  19 #include "mozilla/Variant.h"
  20 #include "nscore.h"
  21 #include "nsXULAppAPI.h"
  22
  23 #ifdef MOZ_WIDGET_ANDROID
  24 #  include "jni.h"
  25 #endif
  26
  27 #if defined(XP_WIN) && defined(MOZ_SANDBOX)
  28 namespace sandbox {
  29 class BrokerServices;
  30 }
  31 #endif
  32
  33 namespace mozilla {
  34
  35 struct StaticXREAppData;
  36
  37 struct BootstrapConfig {
  38 #if defined(XP_WIN) && defined(MOZ_SANDBOX)
  39   /* Chromium sandbox BrokerServices. */
  40   sandbox::BrokerServices* sandboxBrokerServices;
  41 #endif
  42   /* Pointer to static XRE AppData from application.ini.h */
  43   const StaticXREAppData* appData;
  44   /* When the pointer above is null, points to the (string) path of an
  45    * application.ini file to open and parse.
  46    * When the pointer above is non-null, may indicate the directory where
  47    * application files are, relative to the XRE. */
  48   const char* appDataPath;
  49 };
  50
  51 /**
  52  * This class is virtual abstract so that using it does not require linking
  53  * any symbols. The singleton instance of this class is obtained from the
  54  * exported method XRE_GetBootstrap.
  55  */
  56 class Bootstrap {
  57  protected:
  58   Bootstrap() {}
  59
  60   // Because of allocator mismatches, code outside libxul shouldn't delete a
  61   // Bootstrap instance. Use Dispose().
  62   virtual ~Bootstrap() {}
  63
  64   /**
  65    * Destroy and deallocate this Bootstrap instance.
  66    */
  67   virtual void Dispose() = 0;
  68
  69   /**
  70    * Helper class to use with UniquePtr.
  71    */
  72   class BootstrapDelete {
  73    public:
  74     constexpr BootstrapDelete() {}
  75     void operator()(Bootstrap* aPtr) const { aPtr->Dispose(); }
  76   };
  77
  78  public:
  79   typedef mozilla::UniquePtr<Bootstrap, BootstrapDelete> UniquePtr;
  80
  81   virtual void NS_LogInit() = 0;
  82
  83   virtual void NS_LogTerm() = 0;
  84
  85   virtual void XRE_TelemetryAccumulate(int aID, uint32_t aSample) = 0;
  86
  87   virtual void XRE_StartupTimelineRecord(int aEvent,
  88                                          mozilla::TimeStamp aWhen) = 0;
  89
  90   virtual int XRE_main(int argc, char* argv[],
  91                        const BootstrapConfig& aConfig) = 0;
  92
  93   virtual void XRE_StopLateWriteChecks() = 0;
  94
  95   virtual int XRE_XPCShellMain(int argc, char** argv, char** envp,
  96                                const XREShellData* aShellData) = 0;
  97
  98   virtual nsresult XRE_InitChildProcess(int argc, char* argv[],
  99                                         const XREChildData* aChildData) = 0;
 100
 101   virtual void XRE_EnableSameExecutableForContentProc() = 0;
 102
 103 #ifdef MOZ_WIDGET_ANDROID
 104   virtual void XRE_SetGeckoThreadEnv(JNIEnv* aEnv) = 0;
 105
 106   virtual void XRE_SetAndroidChildFds(JNIEnv* aEnv, jintArray aFds) = 0;
 107 #  ifdef MOZ_PROFILE_GENERATE
 108   virtual void XRE_WriteLLVMProfData() = 0;
 109 #  endif
 110 #endif
 111
 112 #ifdef LIBFUZZER
 113   virtual void XRE_LibFuzzerSetDriver(LibFuzzerDriver aDriver) = 0;
 114 #endif
 115
 116 #ifdef MOZ_ENABLE_FORKSERVER
 117   virtual int XRE_ForkServer(int* argc, char*** argv) = 0;
 118 #endif
 119 };
 120
 121 enum class LibLoadingStrategy {
 122   NoReadAhead,
 123   ReadAhead,
 124 };
 125
 126 #if defined(XP_WIN)
 127 using DLErrorType = unsigned long;  // (DWORD)
 128 #else
 129 using DLErrorType = UniqueFreePtr<char>;
 130 #endif
 131
 132 using BootstrapError = Variant<nsresult, DLErrorType>;
 133
 134 using BootstrapResult = ::mozilla::Result<Bootstrap::UniquePtr, BootstrapError>;
 135
 136 /**
 137  * Creates and returns the singleton instance of the bootstrap object.
 138  * @param `b` is an outparam. We use a parameter and not a return value
 139  *        because MSVC doesn't let us return a c++ class from a function with
 140  *        "C" linkage. On failure this will be null.
 141  * @note This function may only be called once and will crash if called again.
 142  */
 143 #ifdef XPCOM_GLUE
 144 typedef void (*GetBootstrapType)(Bootstrap::UniquePtr&);
 145 BootstrapResult GetBootstrap(
 146     const char* aXPCOMFile = nullptr,
 147     LibLoadingStrategy aLibLoadingStrategy = LibLoadingStrategy::NoReadAhead);
 148 #else
 149 extern "C" NS_EXPORT void NS_FROZENCALL
 150 XRE_GetBootstrap(Bootstrap::UniquePtr& b);
 151
 152 inline BootstrapResult GetBootstrap(
 153     const char* aXPCOMFile = nullptr,
 154     LibLoadingStrategy aLibLoadingStrategy = LibLoadingStrategy::NoReadAhead) {
 155   Bootstrap::UniquePtr bootstrap;
 156   XRE_GetBootstrap(bootstrap);
 157   return bootstrap;
 158 }
 159 #endif
 160
 161 #if defined(XP_WIN) && defined(_M_X64) && defined(MOZ_DIAGNOSTIC_ASSERT_ENABLED)
 162 extern "C" NS_EXPORT bool XRE_CheckBlockScopeStaticVarInit(uint32_t* aTlsIndex);
 163 #endif  // XP_WIN && _M_X64 && MOZ_DIAGNOSTIC_ASSERT_ENABLED
 164
 165 }  // namespace mozilla
 166
 167 #endif  // mozilla_Bootstrap_h