gecko-dev/xpcom/components/nsComponentManager.h

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef nsComponentManager_h__
#define nsComponentManager_h__

#include "nsXPCOM.h"

#include "xpcom-private.h"
#include "nsIComponentManager.h"
#include "nsIComponentRegistrar.h"
#include "nsIServiceManager.h"
#include "nsIFile.h"
#include "mozilla/MemoryReporting.h"
#include "mozilla/Module.h"
#include "mozilla/ModuleLoader.h"
#include "mozilla/Mutex.h"
#include "nsXULAppAPI.h"
#include "nsNativeComponentLoader.h"
#include "nsIFactory.h"
#include "nsIInterfaceRequestor.h"
#include "nsIInterfaceRequestorUtils.h"
#include "pldhash.h"
#include "prtime.h"
#include "nsCOMPtr.h"
#include "nsAutoPtr.h"
#include "nsWeakReference.h"
#include "plarena.h"
#include "nsCOMArray.h"
#include "nsDataHashtable.h"
#include "nsInterfaceHashtable.h"
#include "nsClassHashtable.h"
#include "nsTArray.h"

#include "mozilla/Omnijar.h"
#include "mozilla/Attributes.h"

struct nsFactoryEntry;
class nsIMemoryReporter;
class nsIServiceManager;
struct PRThread;

#define NS_COMPONENTMANAGER_CID                      \
{ /* 91775d60-d5dc-11d2-92fb-00e09805570f */         \
    0x91775d60,                                      \
    0xd5dc,                                          \
    0x11d2,                                          \
    {0x92, 0xfb, 0x00, 0xe0, 0x98, 0x05, 0x57, 0x0f} \
}

/* keys for registry use */
extern const char xpcomKeyName[];
extern const char xpcomComponentsKeyName[];
extern const char lastModValueName[];
extern const char fileSizeValueName[];
extern const char nativeComponentType[];
extern const char staticComponentType[];

#ifdef DEBUG
#define XPCOM_CHECK_PENDING_CIDS
#endif
////////////////////////////////////////////////////////////////////////////////

extern const mozilla::Module kXPCOMModule;

/**
 * This is a wrapper around mozilla::Mutex which provides runtime
 * checking for a deadlock where the same thread tries to lock a mutex while
 * it is already locked. This checking is present in both debug and release
 * builds.
 */
class SafeMutex
{
public:
    SafeMutex(const char* name)
        : mMutex(name)
        , mOwnerThread(nullptr)
    { }
    ~SafeMutex()
    { }

    void Lock()
    {
        AssertNotCurrentThreadOwns();
        mMutex.Lock();
        MOZ_ASSERT(mOwnerThread == nullptr);
        mOwnerThread = PR_GetCurrentThread();
    }

    void Unlock()
    {
        MOZ_ASSERT(mOwnerThread == PR_GetCurrentThread());
        mOwnerThread = nullptr;
        mMutex.Unlock();
    }

    void AssertCurrentThreadOwns() const
    {
        // This method is a debug-only check
        MOZ_ASSERT(mOwnerThread == PR_GetCurrentThread());
    }

    MOZ_NEVER_INLINE void AssertNotCurrentThreadOwns() const
    {
        // This method is a release-mode check
        if (PR_GetCurrentThread() == mOwnerThread) {
            MOZ_CRASH();
        }
    }

private:
    mozilla::Mutex mMutex;
    volatile PRThread* mOwnerThread;
};

typedef mozilla::BaseAutoLock<SafeMutex> SafeMutexAutoLock;
typedef mozilla::BaseAutoUnlock<SafeMutex> SafeMutexAutoUnlock;

class nsComponentManagerImpl MOZ_FINAL
    : public nsIComponentManager
    , public nsIServiceManager
    , public nsSupportsWeakReference
    , public nsIComponentRegistrar
    , public nsIInterfaceRequestor
{
public:
    NS_DECL_THREADSAFE_ISUPPORTS
    NS_DECL_NSIINTERFACEREQUESTOR
    NS_DECL_NSICOMPONENTMANAGER
    NS_DECL_NSICOMPONENTREGISTRAR

    static nsresult Create(nsISupports* aOuter, REFNSIID aIID, void** aResult);

    nsresult RegistryLocationForFile(nsIFile* aFile,
                                     nsCString& aResult);
    nsresult FileForRegistryLocation(const nsCString &aLocation,
                                     nsIFile **aSpec);

    NS_DECL_NSISERVICEMANAGER

    // nsComponentManagerImpl methods:
    nsComponentManagerImpl();

    static nsComponentManagerImpl* gComponentManager;
    nsresult Init();

    nsresult Shutdown(void);

    nsresult FreeServices();

    already_AddRefed<mozilla::ModuleLoader> LoaderForExtension(const nsACString& aExt);
    nsInterfaceHashtable<nsCStringHashKey, mozilla::ModuleLoader> mLoaderMap;

    already_AddRefed<nsIFactory> FindFactory(const nsCID& aClass);
    already_AddRefed<nsIFactory> FindFactory(const char *contractID,
                                             uint32_t aContractIDLen);

    already_AddRefed<nsIFactory> LoadFactory(nsFactoryEntry *aEntry);

    nsFactoryEntry *GetFactoryEntry(const char *aContractID,
                                    uint32_t aContractIDLen);
    nsFactoryEntry *GetFactoryEntry(const nsCID &aClass);

    nsDataHashtable<nsIDHashKey, nsFactoryEntry*> mFactories;
    nsDataHashtable<nsCStringHashKey, nsFactoryEntry*> mContractIDs;

    SafeMutex mLock;

    static void InitializeStaticModules();
    static void InitializeModuleLocations();

    struct ComponentLocation
    {
        NSLocationType type;
        mozilla::FileLocation location;
    };

    class ComponentLocationComparator
    {
    public:
      bool Equals(const ComponentLocation& a, const ComponentLocation& b) const
      {
        return (a.type == b.type && a.location.Equals(b.location));
      }
    };

    static nsTArray<const mozilla::Module*>* sStaticModules;
    static nsTArray<ComponentLocation>* sModuleLocations;

    nsNativeModuleLoader mNativeModuleLoader;

    class KnownModule
    {
    public:
        /**
         * Static or binary module.
         */
        KnownModule(const mozilla::Module* aModule, mozilla::FileLocation &aFile)
            : mModule(aModule)
            , mFile(aFile)
            , mLoaded(false)
            , mFailed(false)
        { }

        KnownModule(const mozilla::Module* aModule)
            : mModule(aModule)
            , mLoaded(false)
            , mFailed(false)
        { }

        KnownModule(mozilla::FileLocation &aFile)
            : mModule(NULL)
            , mFile(aFile)
            , mLoader(NULL)
            , mLoaded(false)
            , mFailed(false)
        { }

        ~KnownModule()
        {
            if (mLoaded && mModule->unloadProc)
                mModule->unloadProc();
        }

        bool EnsureLoader();
        bool Load();

        const mozilla::Module* Module() const
        {
            return mModule;
        }

        /**
         * For error logging, get a description of this module, either the
         * file path, or <static module>.
         */
        nsCString Description() const;

    private:
        const mozilla::Module* mModule;
        mozilla::FileLocation mFile;
        nsCOMPtr<mozilla::ModuleLoader> mLoader;
        bool mLoaded;
        bool mFailed;
    };

    // The KnownModule is kept alive by these members, it is
    // referenced by pointer from the factory entries.
    nsTArray< nsAutoPtr<KnownModule> > mKnownStaticModules;
    // The key is the URI string of the module
    nsClassHashtable<nsCStringHashKey, KnownModule> mKnownModules;

    // Mutex not held
    void RegisterModule(const mozilla::Module* aModule,
                        mozilla::FileLocation* aFile);


    // Mutex held
    void RegisterCIDEntryLocked(const mozilla::Module::CIDEntry* aEntry,
                          KnownModule* aModule);
    void RegisterContractIDLocked(const mozilla::Module::ContractIDEntry* aEntry);

    // Mutex not held
    void RegisterManifest(NSLocationType aType, mozilla::FileLocation &aFile,
                          bool aChromeOnly);

    struct ManifestProcessingContext
    {
        ManifestProcessingContext(NSLocationType aType, mozilla::FileLocation &aFile, bool aChromeOnly)
            : mType(aType)
            , mFile(aFile)
            , mChromeOnly(aChromeOnly)
        { }

        ~ManifestProcessingContext() { }

        NSLocationType mType;
        mozilla::FileLocation mFile;
        bool mChromeOnly;
    };

    void ManifestManifest(ManifestProcessingContext& cx, int lineno, char *const * argv);
    void ManifestBinaryComponent(ManifestProcessingContext& cx, int lineno, char *const * argv);
    void ManifestXPT(ManifestProcessingContext& cx, int lineno, char *const * argv);
    void ManifestComponent(ManifestProcessingContext& cx, int lineno, char *const * argv);
    void ManifestContract(ManifestProcessingContext& cx, int lineno, char* const * argv);
    void ManifestCategory(ManifestProcessingContext& cx, int lineno, char* const * argv);

    void RereadChromeManifests(bool aChromeOnly = true);

    // Shutdown
    enum {
        NOT_INITIALIZED,
        NORMAL,
        SHUTDOWN_IN_PROGRESS,
        SHUTDOWN_COMPLETE
    } mStatus;

    PLArenaPool   mArena;

    struct PendingServiceInfo {
      const nsCID* cid;
      PRThread* thread;
    };

    inline PendingServiceInfo* AddPendingService(const nsCID& aServiceCID,
                                                 PRThread* aThread);
    inline void RemovePendingService(const nsCID& aServiceCID);
    inline PRThread* GetPendingServiceThread(const nsCID& aServiceCID) const;

    nsTArray<PendingServiceInfo> mPendingServices;

    size_t SizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf);

private:
    ~nsComponentManagerImpl();

    nsCOMPtr<nsIMemoryReporter> mReporter;
};


#define NS_MAX_FILENAME_LEN     1024

#define NS_ERROR_IS_DIR NS_ERROR_GENERATE_FAILURE(NS_ERROR_MODULE_XPCOM, 24)

struct nsFactoryEntry
{
    nsFactoryEntry(const mozilla::Module::CIDEntry* entry,
                   nsComponentManagerImpl::KnownModule* module);

    // nsIComponentRegistrar.registerFactory support
    nsFactoryEntry(const nsCID& aClass, nsIFactory* factory);

    ~nsFactoryEntry();

    already_AddRefed<nsIFactory> GetFactory();

    size_t SizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf);

    const mozilla::Module::CIDEntry* mCIDEntry;
    nsComponentManagerImpl::KnownModule* mModule;

    nsCOMPtr<nsIFactory>   mFactory;
    nsCOMPtr<nsISupports>  mServiceObject;
};

#endif // nsComponentManager_h__