widget/windows/IEnumFE.h

   1 /* -*- Mode: C++; tab-width: 2; 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 #ifndef IEnumeFE_h__
   7 #define IEnumeFE_h__
   8
   9 /*
  10  * CEnumFormatEtc - implements IEnumFORMATETC
  11  */
  12
  13 #include <ole2.h>
  14
  15 #include "nsTArray.h"
  16 #include "mozilla/Attributes.h"
  17
  18 // FORMATETC container
  19 class FormatEtc
  20 {
  21 public:
  22   FormatEtc() { memset(&mFormat, 0, sizeof(FORMATETC)); }
  23   FormatEtc(const FormatEtc& copy) { CopyIn(&copy.mFormat); }
  24   ~FormatEtc() { if (mFormat.ptd) CoTaskMemFree(mFormat.ptd); }
  25
  26   void CopyIn(const FORMATETC *aSrc) {
  27     if (!aSrc) {
  28         memset(&mFormat, 0, sizeof(FORMATETC));
  29         return;
  30     }
  31     mFormat = *aSrc;
  32     if (aSrc->ptd) {
  33         mFormat.ptd = (DVTARGETDEVICE*)CoTaskMemAlloc(sizeof(DVTARGETDEVICE));
  34         *(mFormat.ptd) = *(aSrc->ptd);
  35     }
  36   }
  37
  38   void CopyOut(LPFORMATETC aDest) {
  39     if (!aDest)
  40         return;
  41     *aDest = mFormat;
  42     if (mFormat.ptd) {
  43         aDest->ptd = (DVTARGETDEVICE*)CoTaskMemAlloc(sizeof(DVTARGETDEVICE));
  44         *(aDest->ptd) = *(mFormat.ptd);
  45     }
  46   }
  47
  48 private:
  49   FORMATETC mFormat;
  50 };
  51
  52 /*
  53  * CEnumFormatEtc is created within IDataObject::EnumFormatEtc. This object lives
  54  * on its own, that is, QueryInterface only knows IUnknown and IEnumFormatEtc,
  55  * nothing more.  We still use an outer unknown for reference counting, because as
  56  * long as this enumerator lives, the data object should live, thereby keeping the
  57  * application up.
  58  */
  59
  60 class CEnumFormatEtc MOZ_FINAL : public IEnumFORMATETC
  61 {
  62 public:
  63     CEnumFormatEtc(nsTArray<FormatEtc>& aArray);
  64     CEnumFormatEtc();
  65     ~CEnumFormatEtc();
  66
  67     // IUnknown impl.
  68     STDMETHODIMP QueryInterface(REFIID riid, LPVOID *ppv);
  69     STDMETHODIMP_(ULONG) AddRef();
  70     STDMETHODIMP_(ULONG) Release();
  71
  72     // IEnumFORMATETC impl.
  73     STDMETHODIMP Next(ULONG aMaxToFetch, FORMATETC *aResult, ULONG *aNumFetched);
  74     STDMETHODIMP Skip(ULONG aSkipNum);
  75     STDMETHODIMP Reset();
  76     STDMETHODIMP Clone(LPENUMFORMATETC *aResult); // Addrefs
  77
  78     // Utils
  79     void AddFormatEtc(LPFORMATETC aFormat);
  80
  81 private:
  82     nsTArray<FormatEtc> mFormatList; // Formats
  83     ULONG mRefCnt; // Object reference count
  84     ULONG mCurrentIdx; // Current element
  85
  86     void SetIndex(uint32_t aIdx);
  87 };
  88
  89
  90 #endif //_IENUMFE_H_