include/svl/poolitem.hxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  *
   9  * This file incorporates work covered by the following license notice:
  10  *
  11  *   Licensed to the Apache Software Foundation (ASF) under one or more
  12  *   contributor license agreements. See the NOTICE file distributed
  13  *   with this work for additional information regarding copyright
  14  *   ownership. The ASF licenses this file to you under the Apache
  15  *   License, Version 2.0 (the "License"); you may not use this file
  16  *   except in compliance with the License. You may obtain a copy of
  17  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  18  */
  19
  20 #ifndef INCLUDED_SVL_POOLITEM_HXX
  21 #define INCLUDED_SVL_POOLITEM_HXX
  22
  23 #include <sal/config.h>
  24
  25 #include <memory>
  26 #include <vector>
  27
  28 #include <com/sun/star/uno/Any.hxx>
  29 #include <svl/hint.hxx>
  30 #include <svl/svldllapi.h>
  31 #include <svl/typedwhich.hxx>
  32 #include <tools/mapunit.hxx>
  33 #include <tools/long.hxx>
  34 #include <boost/property_tree/ptree_fwd.hpp>
  35
  36 class IntlWrapper;
  37
  38 enum class SfxItemKind : sal_Int8
  39 {
  40    NONE,
  41    DeleteOnIdle,
  42    StaticDefault,
  43    PoolDefault
  44 };
  45
  46 #define SFX_ITEMS_OLD_MAXREF                0xffef
  47 #define SFX_ITEMS_MAXREF                    0xfffffffe
  48 #define SFX_ITEMS_SPECIAL                   0xffffffff
  49
  50 #define CONVERT_TWIPS                       0x80    // Uno conversion for measurement (for MemberId)
  51
  52 // warning, if there is no boolean inside the any this will always return the value false
  53 inline bool Any2Bool( const css::uno::Any&rValue )
  54 {
  55     bool bValue = false;
  56     if( !(rValue >>= bValue) )
  57     {
  58         sal_Int32 nNum = 0;
  59         if( rValue >>= nNum )
  60             bValue = nNum != 0;
  61     }
  62
  63     return bValue;
  64 }
  65
  66 /*
  67  * The values of this enum describe the degree of textual
  68  * representation of an item after calling the virtual
  69  * method <SfxPoolItem::GetPresentation()const>.
  70  */
  71 enum class SfxItemPresentation
  72 {
  73     Nameless,
  74     Complete
  75 };
  76
  77 /**
  78  * These values have to match the values in the
  79  * css::frame::status::ItemState IDL
  80  * to be found at offapi/com/sun/star/frame/status/ItemState.idl
  81 */
  82 enum class SfxItemState {
  83
  84     /** Specifies an unknown state. */
  85     UNKNOWN  = 0,
  86
  87     /** Specifies that the property is currently disabled. */
  88     DISABLED = 0x0001,
  89
  90     /** Specifies that the property is currently in a don't care state.
  91      * <br/>
  92      * This is normally used if a selection provides more than one state
  93      * for a property at the same time.
  94      */
  95     DONTCARE = 0x0010,
  96
  97     /** Specifies that the property is currently in a default state. */
  98     DEFAULT  = 0x0020,
  99
 100     /** The property has been explicitly set to a given value hence we know
 101      * we are not taking the default value.
 102      * <br/>
 103      * For example, you may want to get the font color and it might either
 104      * be the default one or one that has been explicitly set.
 105     */
 106     SET      = 0x0040
 107 };
 108
 109 #define INVALID_POOL_ITEM reinterpret_cast<SfxPoolItem*>(-1)
 110
 111 class SfxItemPool;
 112 class SfxItemSet;
 113 typedef struct _xmlTextWriter* xmlTextWriterPtr;
 114
 115 class SVL_DLLPUBLIC SfxPoolItem
 116 {
 117 friend class SfxItemPool;
 118 friend class SfxItemDisruptor_Impl;
 119 friend class SfxItemPoolCache;
 120 friend class SfxItemSet;
 121 friend class SfxVoidItem;
 122
 123     mutable sal_uInt32 m_nRefCount;
 124     sal_uInt16  m_nWhich;
 125     SfxItemKind  m_nKind;
 126
 127 private:
 128     inline void              SetRefCount(sal_uInt32 n);
 129     inline void              SetKind( SfxItemKind n );
 130 public:
 131     inline void              AddRef(sal_uInt32 n = 1) const;
 132 private:
 133     inline sal_uInt32        ReleaseRef(sal_uInt32 n = 1) const;
 134
 135 protected:
 136                              explicit SfxPoolItem( sal_uInt16 nWhich = 0 );
 137                              SfxPoolItem( const SfxPoolItem& rCopy)
 138                                  : SfxPoolItem(rCopy.m_nWhich) {}
 139
 140 public:
 141     virtual                  ~SfxPoolItem();
 142
 143     void                     SetWhich( sal_uInt16 nId )
 144                              {
 145                                  // can only change the Which before we are in a set
 146                                  assert(m_nRefCount==0);
 147                                  m_nWhich = nId;
 148                              }
 149     sal_uInt16               Which() const { return m_nWhich; }
 150     // StaticWhichCast asserts if the TypedWhichId is not matching its type, otherwise it returns a reference.
 151     // You can use StaticWhichCast when you are sure about the type at compile time -- like a static_cast.
 152     template<class T> T& StaticWhichCast(TypedWhichId<T> nId)
 153     {
 154         (void)nId;
 155         assert(nId == m_nWhich);
 156         assert(dynamic_cast<T*>(this));
 157         return *static_cast<T*>(this);
 158     }
 159     template<class T> const T& StaticWhichCast(TypedWhichId<T> nId) const
 160     {
 161         (void)nId;
 162         assert(nId == m_nWhich);
 163         assert(dynamic_cast<const T*>(this));
 164         return *static_cast<const T*>(this);
 165     }
 166     // DynamicWhichCast returns nullptr if the TypedWhichId is not matching its type, otherwise it returns a typed pointer.
 167     // it asserts if the TypedWhichId matches its Which, but not the RTTI type.
 168     // You can use DynamicWhichCast when you are not sure about the type at compile time -- like a dynamic_cast.
 169     template<class T> T* DynamicWhichCast(TypedWhichId<T> nId)
 170     {
 171         if(m_nWhich != nId)
 172             return nullptr;
 173         assert(dynamic_cast<T*>(this));
 174         return static_cast<T*>(this);
 175     }
 176     template<class T> const T* DynamicWhichCast(TypedWhichId<T> nId) const
 177     {
 178         if(m_nWhich != nId)
 179             return nullptr;
 180         assert(dynamic_cast<const T*>(this));
 181         return static_cast<const T*>(this);
 182     }
 183     virtual bool             operator==( const SfxPoolItem& ) const = 0;
 184     bool                     operator!=( const SfxPoolItem& rItem ) const
 185                              { return !(*this == rItem); }
 186
 187     // Sorting is only used for faster searching in a pool which contains large quantities
 188     // of a single kind of pool item.
 189     virtual bool             operator<( const SfxPoolItem& ) const { assert(false); return false; }
 190     virtual bool             IsSortable() const { return false; }
 191
 192     // Some item types cannot be IsSortable() (such as because they are modified while stored
 193     // in a pool, which would change the ordering position, see e.g. 585e0ac43b9bd8a2f714903034).
 194     // To improve performance in such cases it is possible to reimplement Lookup() to do a linear
 195     // lookup optimized for the specific class (avoiding virtual functions may allow the compiler
 196     // to generate better code and class-specific optimizations such as hashing or caching may
 197     // be used.)
 198     // If reimplemented, the Lookup() function should search [begin,end) for an item matching
 199     // this object and return an iterator pointing to the item or the end iterator.
 200     virtual bool             HasLookup() const { return false; }
 201     typedef std::vector<SfxPoolItem*>::const_iterator lookup_iterator;
 202     virtual lookup_iterator  Lookup(lookup_iterator /*begin*/, lookup_iterator end ) const
 203                              { assert( false ); return end; }
 204
 205     /**  @return true if it has a valid string representation */
 206     virtual bool             GetPresentation( SfxItemPresentation ePresentation,
 207                                     MapUnit eCoreMetric,
 208                                     MapUnit ePresentationMetric,
 209                                     OUString &rText,
 210                                     const IntlWrapper& rIntlWrapper ) const;
 211
 212     virtual void             ScaleMetrics( tools::Long lMult, tools::Long lDiv );
 213     virtual bool             HasMetrics() const;
 214
 215     virtual bool             QueryValue( css::uno::Any& rVal, sal_uInt8 nMemberId = 0 ) const;
 216     virtual bool             PutValue( const css::uno::Any& rVal, sal_uInt8 nMemberId );
 217
 218     virtual SfxPoolItem*     Clone( SfxItemPool *pPool = nullptr ) const = 0;
 219     // clone and call SetWhich
 220     std::unique_ptr<SfxPoolItem> CloneSetWhich( sal_uInt16 nNewWhich ) const;
 221     template<class T> std::unique_ptr<T> CloneSetWhich( TypedWhichId<T> nId ) const
 222     {
 223         return std::unique_ptr<T>(static_cast<T*>(CloneSetWhich(sal_uInt16(nId)).release()));
 224     }
 225
 226     sal_uInt32               GetRefCount() const { return m_nRefCount; }
 227     SfxItemKind       GetKind() const { return m_nKind; }
 228     virtual void dumpAsXml(xmlTextWriterPtr pWriter) const;
 229     virtual boost::property_tree::ptree dumpAsJSON() const;
 230
 231     /** Only SfxVoidItem shall and must return true for this.
 232
 233         This avoids costly calls to dynamic_cast<const SfxVoidItem*>()
 234         specifically in SfxItemSet::GetItemState()
 235      */
 236     virtual bool             IsVoidItem() const;
 237
 238 private:
 239     SfxPoolItem&             operator=( const SfxPoolItem& ) = delete;
 240 };
 241
 242 inline void SfxPoolItem::SetRefCount(sal_uInt32 n)
 243 {
 244     m_nRefCount = n;
 245     m_nKind = SfxItemKind::NONE;
 246 }
 247
 248 inline void SfxPoolItem::SetKind( SfxItemKind n )
 249 {
 250     m_nRefCount = SFX_ITEMS_SPECIAL;
 251     m_nKind = n;
 252 }
 253
 254 inline void SfxPoolItem::AddRef(sal_uInt32 n) const
 255 {
 256     assert(m_nRefCount <= SFX_ITEMS_MAXREF && "AddRef with non-Pool-Item");
 257     assert(n <= SFX_ITEMS_MAXREF - m_nRefCount && "AddRef: refcount overflow");
 258     m_nRefCount += n;
 259 }
 260
 261 inline sal_uInt32 SfxPoolItem::ReleaseRef(sal_uInt32 n) const
 262 {
 263     assert(m_nRefCount <= SFX_ITEMS_MAXREF && "ReleaseRef with non-Pool-Item");
 264     assert(n <= m_nRefCount);
 265     m_nRefCount -= n;
 266     return m_nRefCount;
 267 }
 268
 269 inline bool IsPoolDefaultItem(const SfxPoolItem *pItem )
 270 {
 271     return pItem && pItem->GetKind() == SfxItemKind::PoolDefault;
 272 }
 273
 274 inline bool IsStaticDefaultItem(const SfxPoolItem *pItem )
 275 {
 276     return pItem && pItem->GetKind() == SfxItemKind::StaticDefault;
 277 }
 278
 279 inline bool IsDefaultItem( const SfxPoolItem *pItem )
 280 {
 281     return pItem && (pItem->GetKind() == SfxItemKind::StaticDefault || pItem->GetKind() == SfxItemKind::PoolDefault);
 282 }
 283
 284 inline bool IsPooledItem( const SfxPoolItem *pItem )
 285 {
 286     return pItem && pItem->GetRefCount() > 0 && pItem->GetRefCount() <= SFX_ITEMS_MAXREF;
 287 }
 288
 289 inline bool IsInvalidItem(const SfxPoolItem *pItem)
 290 {
 291     return pItem == INVALID_POOL_ITEM;
 292 }
 293
 294 class SVL_DLLPUBLIC SfxVoidItem final: public SfxPoolItem
 295 {
 296 public:
 297                             static SfxPoolItem* CreateDefault();
 298                             explicit SfxVoidItem( sal_uInt16 nWhich );
 299                             virtual ~SfxVoidItem() override;
 300
 301     SfxVoidItem(SfxVoidItem const &) = default;
 302     SfxVoidItem(SfxVoidItem &&) = default;
 303     SfxVoidItem & operator =(SfxVoidItem const &) = delete; // due to SfxPoolItem
 304     SfxVoidItem & operator =(SfxVoidItem &&) = delete; // due to SfxPoolItem
 305
 306     virtual bool            operator==( const SfxPoolItem& ) const override;
 307
 308     virtual bool GetPresentation( SfxItemPresentation ePres,
 309                                     MapUnit eCoreMetric,
 310                                     MapUnit ePresMetric,
 311                                     OUString &rText,
 312                                     const IntlWrapper& ) const override;
 313     virtual void dumpAsXml(xmlTextWriterPtr pWriter) const override;
 314
 315     // create a copy of itself
 316     virtual SfxVoidItem*    Clone( SfxItemPool *pPool = nullptr ) const override;
 317
 318     /** Always returns true as this is an SfxVoidItem. */
 319     virtual bool            IsVoidItem() const override;
 320 };
 321
 322
 323 class SVL_DLLPUBLIC SfxPoolItemHint final : public SfxHint
 324 {
 325     SfxPoolItem* pObj;
 326 public:
 327     explicit SfxPoolItemHint( SfxPoolItem* Object ) : pObj(Object) {}
 328     SfxPoolItem* GetObject() const { return pObj; }
 329 };
 330
 331 #endif
 332
 333 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */