gecko-dev/modules/libpref/public/Preferences.h

396 lines
13 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Mozilla Communicator client code.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Brian Nesse <bnesse@netscape.com>
* Mats Palmgren <matspal@gmail.com>
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#ifndef mozilla_Preferences_h
#define mozilla_Preferences_h
#ifndef MOZILLA_INTERNAL_API
#error "This header is only usable from within libxul (MOZILLA_INTERNAL_API)."
#endif
#include "nsIPrefService.h"
#include "nsIPrefBranch.h"
#include "nsIPrefBranchInternal.h"
#include "nsIObserver.h"
#include "nsCOMPtr.h"
#include "nsWeakReference.h"
class nsIFile;
class nsCString;
class nsString;
class nsAdoptingString;
class nsAdoptingCString;
#ifndef have_PrefChangedFunc_typedef
typedef int (*PR_CALLBACK PrefChangedFunc)(const char *, void *);
#define have_PrefChangedFunc_typedef
#endif
namespace mozilla {
class Preferences : public nsIPrefService,
public nsIObserver,
public nsIPrefBranchInternal,
public nsSupportsWeakReference
{
public:
NS_DECL_ISUPPORTS
NS_DECL_NSIPREFSERVICE
NS_FORWARD_NSIPREFBRANCH(sRootBranch->)
NS_DECL_NSIOBSERVER
Preferences();
virtual ~Preferences();
nsresult Init();
/**
* Reset loaded user prefs then read them
*/
static nsresult ResetAndReadUserPrefs();
/**
* Returns the singleton instance which is addreffed.
*/
static Preferences* GetInstanceForService();
/**
* Finallizes global members.
*/
static void Shutdown();
/**
* Returns shared pref service instance
* NOTE: not addreffed.
*/
static nsIPrefService* GetService()
{
NS_ENSURE_TRUE(InitStaticMembers(), nsnull);
return sPreferences;
}
/**
* Returns shared pref branch instance.
* NOTE: not addreffed.
*/
static nsIPrefBranch* GetRootBranch()
{
NS_ENSURE_TRUE(InitStaticMembers(), nsnull);
return sRootBranch;
}
/**
* Returns shared default pref branch instance.
* NOTE: not addreffed.
*/
static nsIPrefBranch* GetDefaultRootBranch()
{
NS_ENSURE_TRUE(InitStaticMembers(), nsnull);
return sDefaultRootBranch;
}
/**
* Gets int or bool type pref value with default value if failed to get
* the pref.
*/
static bool GetBool(const char* aPref, bool aDefault = false)
{
bool result = aDefault;
GetBool(aPref, &result);
return result;
}
static PRInt32 GetInt(const char* aPref, PRInt32 aDefault = 0)
{
PRInt32 result = aDefault;
GetInt(aPref, &result);
return result;
}
static PRUint32 GetUint(const char* aPref, PRUint32 aDefault = 0)
{
PRUint32 result = aDefault;
GetUint(aPref, &result);
return result;
}
/**
* Gets char type pref value directly. If failed, the get() of result
* returns NULL. Even if succeeded but the result was empty string, the
* get() does NOT return NULL. So, you can check whether the method
* succeeded or not by:
*
* nsAdoptingString value = Prefereces::GetString("foo.bar");
* if (!value) {
* // failed
* }
*
* Be aware. If you wrote as:
*
* nsAutoString value = Preferences::GetString("foo.bar");
* if (!value.get()) {
* // the condition is always FALSE!!
* }
*
* The value.get() doesn't return NULL. You must use nsAdoptingString when
* you need to check whether it was failure or not.
*/
static nsAdoptingCString GetCString(const char* aPref);
static nsAdoptingString GetString(const char* aPref);
static nsAdoptingCString GetLocalizedCString(const char* aPref);
static nsAdoptingString GetLocalizedString(const char* aPref);
/**
* Gets int or bool type pref value with raw return value of nsIPrefBranch.
*
* @param aPref A pref name.
* @param aResult Must not be NULL. The value is never modified when
* these methods fail.
*/
static nsresult GetBool(const char* aPref, bool* aResult);
static nsresult GetInt(const char* aPref, PRInt32* aResult);
static nsresult GetUint(const char* aPref, PRUint32* aResult)
{
PRInt32 result;
nsresult rv = GetInt(aPref, &result);
if (NS_SUCCEEDED(rv)) {
*aResult = static_cast<PRUint32>(result);
}
return rv;
}
/**
* Gets string type pref value with raw return value of nsIPrefBranch.
*
* @param aPref A pref name.
* @param aResult Must not be NULL. The value is never modified when
* these methods fail.
*/
static nsresult GetCString(const char* aPref, nsACString* aResult);
static nsresult GetString(const char* aPref, nsAString* aResult);
static nsresult GetLocalizedCString(const char* aPref, nsACString* aResult);
static nsresult GetLocalizedString(const char* aPref, nsAString* aResult);
static nsresult GetComplex(const char* aPref, const nsIID &aType,
void** aResult);
/**
* Sets various type pref values.
*/
static nsresult SetBool(const char* aPref, bool aValue);
static nsresult SetInt(const char* aPref, PRInt32 aValue);
static nsresult SetUint(const char* aPref, PRUint32 aValue)
{
return SetInt(aPref, static_cast<PRInt32>(aValue));
}
static nsresult SetCString(const char* aPref, const char* aValue);
static nsresult SetCString(const char* aPref, const nsACString &aValue);
static nsresult SetString(const char* aPref, const PRUnichar* aValue);
static nsresult SetString(const char* aPref, const nsAString &aValue);
static nsresult SetComplex(const char* aPref, const nsIID &aType,
nsISupports* aValue);
/**
* Clears user set pref.
*/
static nsresult ClearUser(const char* aPref);
/**
* Whether the pref has a user value or not.
*/
static bool HasUserValue(const char* aPref);
/**
* Gets the type of the pref.
*/
static PRInt32 GetType(const char* aPref);
/**
* Adds/Removes the observer for the root pref branch.
* The observer is referenced strongly if AddStrongObserver is used. On the
* other hand, it is referenced weakly, if AddWeakObserver is used.
* See nsIPrefBran2.idl for the detail.
*/
static nsresult AddStrongObserver(nsIObserver* aObserver, const char* aPref);
static nsresult AddWeakObserver(nsIObserver* aObserver, const char* aPref);
static nsresult RemoveObserver(nsIObserver* aObserver, const char* aPref);
/**
* Adds/Removes two or more observers for the root pref branch.
* Pass to aPrefs an array of const char* whose last item is NULL.
*/
static nsresult AddStrongObservers(nsIObserver* aObserver,
const char** aPrefs);
static nsresult AddWeakObservers(nsIObserver* aObserver,
const char** aPrefs);
static nsresult RemoveObservers(nsIObserver* aObserver,
const char** aPrefs);
/**
* Registers/Unregisters the callback function for the aPref.
*/
static nsresult RegisterCallback(PrefChangedFunc aCallback,
const char* aPref,
void* aClosure = nsnull);
static nsresult UnregisterCallback(PrefChangedFunc aCallback,
const char* aPref,
void* aClosure = nsnull);
/**
* Adds the aVariable to cache table. aVariable must be a pointer for a
* static variable. The value will be modified when the pref value is
* changed but note that even if you modified it, the value isn't assigned to
* the pref.
*/
static nsresult AddBoolVarCache(bool* aVariable,
const char* aPref,
bool aDefault = false);
static nsresult AddIntVarCache(PRInt32* aVariable,
const char* aPref,
PRInt32 aDefault = 0);
static nsresult AddUintVarCache(PRUint32* aVariable,
const char* aPref,
PRUint32 aDefault = 0);
/**
* Gets the default bool, int or uint value of the pref.
* The result is raw result of nsIPrefBranch::Get*Pref().
* If the pref could have any value, you needed to use these methods.
* If not so, you could use below methods.
*/
static nsresult GetDefaultBool(const char* aPref, bool* aResult);
static nsresult GetDefaultInt(const char* aPref, PRInt32* aResult);
static nsresult GetDefaultUint(const char* aPref, PRUint32* aResult)
{
return GetDefaultInt(aPref, reinterpret_cast<PRInt32*>(aResult));
}
/**
* Gets the default bool, int or uint value of the pref directly.
* You can set an invalid value of the pref to aFailedResult. If these
* methods failed to get the default value, they would return the
* aFailedResult value.
*/
static bool GetDefaultBool(const char* aPref, bool aFailedResult)
{
bool result;
return NS_SUCCEEDED(GetDefaultBool(aPref, &result)) ? result :
aFailedResult;
}
static PRInt32 GetDefaultInt(const char* aPref, PRInt32 aFailedResult)
{
PRInt32 result;
return NS_SUCCEEDED(GetDefaultInt(aPref, &result)) ? result : aFailedResult;
}
static PRUint32 GetDefaultUint(const char* aPref, PRUint32 aFailedResult)
{
return static_cast<PRUint32>(
GetDefaultInt(aPref, static_cast<PRInt32>(aFailedResult)));
}
/**
* Gets the default value of the char type pref.
* If the get() of the result returned NULL, that meant the value didn't
* have default value.
*
* See the comment at definition at GetString() and GetCString() for more
* details of the result.
*/
static nsAdoptingString GetDefaultString(const char* aPref);
static nsAdoptingCString GetDefaultCString(const char* aPref);
static nsAdoptingString GetDefaultLocalizedString(const char* aPref);
static nsAdoptingCString GetDefaultLocalizedCString(const char* aPref);
static nsresult GetDefaultCString(const char* aPref, nsACString* aResult);
static nsresult GetDefaultString(const char* aPref, nsAString* aResult);
static nsresult GetDefaultLocalizedCString(const char* aPref,
nsACString* aResult);
static nsresult GetDefaultLocalizedString(const char* aPref,
nsAString* aResult);
static nsresult GetDefaultComplex(const char* aPref, const nsIID &aType,
void** aResult);
/**
* Gets the type of the pref.
*/
static PRInt32 GetDefaultType(const char* aPref);
// Used to synchronise preferences between chrome and content processes.
static void MirrorPreferences(nsTArray<PrefTuple,
nsTArrayInfallibleAllocator> *aArray);
static bool MirrorPreference(const char *aPref, PrefTuple *aTuple);
static void ClearContentPref(const char *aPref);
static void SetPreference(const PrefTuple *aTuple);
protected:
nsresult NotifyServiceObservers(const char *aSubject);
/**
* Reads the default pref file or, if that failed, try to save a new one.
*
* @return NS_OK if either action succeeded,
* or the error code related to the read attempt.
*/
nsresult UseDefaultPrefFile();
nsresult UseUserPrefFile();
nsresult ReadAndOwnUserPrefFile(nsIFile *aFile);
nsresult ReadAndOwnSharedUserPrefFile(nsIFile *aFile);
nsresult SavePrefFileInternal(nsIFile* aFile);
nsresult WritePrefFile(nsIFile* aFile);
nsresult MakeBackupPrefFile(nsIFile *aFile);
private:
nsCOMPtr<nsIFile> mCurrentFile;
static Preferences* sPreferences;
static nsIPrefBranch* sRootBranch;
static nsIPrefBranch* sDefaultRootBranch;
static bool sShutdown;
/**
* Init static members. TRUE if it succeeded. Otherwise, FALSE.
*/
static bool InitStaticMembers();
};
} // namespace mozilla
#endif // mozilla_Preferences_h