include/wx/msw/ole/oleutils.h

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        oleutils.h
   3 // Purpose:     OLE helper routines, OLE debugging support &c
   4 // Author:      Vadim Zeitlin
   5 // Modified by:
   6 // Created:     19.02.1998
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) 1998 Vadim Zeitlin <zeitlin@dptmaths.ens-cachan.fr>
   9 // Licence:     wxWindows licence
  10 ///////////////////////////////////////////////////////////////////////////////
  11
  12 #ifndef   _WX_OLEUTILS_H
  13 #define   _WX_OLEUTILS_H
  14
  15 #include "wx/defs.h"
  16
  17 #if wxUSE_OLE
  18
  19 // ole2.h includes windows.h, so include wrapwin.h first
  20 #include "wx/msw/wrapwin.h"
  21 // get IUnknown, REFIID &c
  22 #include <ole2.h>
  23 #include "wx/intl.h"
  24 #include "wx/log.h"
  25
  26 // ============================================================================
  27 // General purpose functions and macros
  28 // ============================================================================
  29
  30 // ----------------------------------------------------------------------------
  31 // initialize/cleanup OLE
  32 // ----------------------------------------------------------------------------
  33
  34 // call OleInitialize() or CoInitialize[Ex]() depending on the platform
  35 //
  36 // return true if ok, false otherwise
  37 inline bool wxOleInitialize()
  38 {
  39     // we need to initialize OLE library
  40 #ifdef __WXWINCE__
  41     if ( FAILED(::CoInitializeEx(NULL, COINIT_MULTITHREADED)) )
  42 #else
  43     if ( FAILED(::OleInitialize(NULL)) )
  44 #endif
  45     {
  46         wxLogError(_("Cannot initialize OLE"));
  47
  48         return false;
  49     }
  50
  51     return true;
  52 }
  53
  54 inline void wxOleUninitialize()
  55 {
  56 #ifdef __WXWINCE__
  57     ::CoUninitialize();
  58 #else
  59     ::OleUninitialize();
  60 #endif
  61 }
  62
  63 // ----------------------------------------------------------------------------
  64 // misc helper functions/macros
  65 // ----------------------------------------------------------------------------
  66
  67 // release the interface pointer (if !NULL)
  68 inline void ReleaseInterface(IUnknown *pIUnk)
  69 {
  70   if ( pIUnk != NULL )
  71     pIUnk->Release();
  72 }
  73
  74 // release the interface pointer (if !NULL) and make it NULL
  75 #define   RELEASE_AND_NULL(p)   if ( (p) != NULL ) { p->Release(); p = NULL; };
  76
  77 // return true if the iid is in the array
  78 extern bool IsIidFromList(REFIID riid, const IID *aIids[], size_t nCount);
  79
  80 // ============================================================================
  81 // IUnknown implementation helpers
  82 // ============================================================================
  83
  84 /*
  85    The most dumb implementation of IUnknown methods. We don't support
  86    aggregation nor containment, but for 99% of cases this simple
  87    implementation is quite enough.
  88
  89    Usage is trivial: here is all you should have
  90    1) DECLARE_IUNKNOWN_METHODS in your (IUnknown derived!) class declaration
  91    2) BEGIN/END_IID_TABLE with ADD_IID in between for all interfaces you
  92       support (at least all for which you intent to return 'this' from QI,
  93       i.e. you should derive from IFoo if you have ADD_IID(Foo)) somewhere else
  94    3) IMPLEMENT_IUNKNOWN_METHODS somewhere also
  95
  96    These macros are quite simple: AddRef and Release are trivial and QI does
  97    lookup in a static member array of IIDs and returns 'this' if it founds
  98    the requested interface in it or E_NOINTERFACE if not.
  99  */
 100
 101 /*
 102   wxAutoULong: this class is used for automatically initalising m_cRef to 0
 103 */
 104 class wxAutoULong
 105 {
 106 public:
 107     wxAutoULong(ULONG value = 0) : m_Value(value) { }
 108
 109     operator ULONG&() { return m_Value; }
 110     ULONG& operator=(ULONG value) { m_Value = value; return m_Value;  }
 111
 112     wxAutoULong& operator++() { ++m_Value; return *this; }
 113     const wxAutoULong operator++( int ) { wxAutoULong temp = *this; ++m_Value; return temp; }
 114
 115     wxAutoULong& operator--() { --m_Value; return *this; }
 116     const wxAutoULong operator--( int ) { wxAutoULong temp = *this; --m_Value; return temp; }
 117
 118 private:
 119     ULONG m_Value;
 120 };
 121
 122 // declare the methods and the member variable containing reference count
 123 // you must also define the ms_aIids array somewhere with BEGIN_IID_TABLE
 124 // and friends (see below)
 125
 126 #define   DECLARE_IUNKNOWN_METHODS                                            \
 127   public:                                                                     \
 128     STDMETHODIMP          QueryInterface(REFIID, void **);                    \
 129     STDMETHODIMP_(ULONG)  AddRef();                                           \
 130     STDMETHODIMP_(ULONG)  Release();                                          \
 131   private:                                                                    \
 132     static  const IID    *ms_aIids[];                                         \
 133     wxAutoULong           m_cRef
 134
 135 // macros for declaring supported interfaces
 136 // NB: you should write ADD_INTERFACE(Foo) and not ADD_INTERFACE(IID_IFoo)!
 137 #define BEGIN_IID_TABLE(cname)  const IID *cname::ms_aIids[] = {
 138 #define ADD_IID(iid)                                             &IID_I##iid,
 139 #define END_IID_TABLE                                          }
 140
 141 // implementation is as straightforward as possible
 142 // Parameter:  classname - the name of the class
 143 #define   IMPLEMENT_IUNKNOWN_METHODS(classname)                               \
 144   STDMETHODIMP classname::QueryInterface(REFIID riid, void **ppv)             \
 145   {                                                                           \
 146     wxLogQueryInterface(_T(#classname), riid);                                \
 147                                                                               \
 148     if ( IsIidFromList(riid, ms_aIids, WXSIZEOF(ms_aIids)) ) {                \
 149       *ppv = this;                                                            \
 150       AddRef();                                                               \
 151                                                                               \
 152       return S_OK;                                                            \
 153     }                                                                         \
 154     else {                                                                    \
 155       *ppv = NULL;                                                            \
 156                                                                               \
 157       return (HRESULT) E_NOINTERFACE;                                         \
 158     }                                                                         \
 159   }                                                                           \
 160                                                                               \
 161   STDMETHODIMP_(ULONG) classname::AddRef()                                    \
 162   {                                                                           \
 163     wxLogAddRef(_T(#classname), m_cRef);                                      \
 164                                                                               \
 165     return ++m_cRef;                                                          \
 166   }                                                                           \
 167                                                                               \
 168   STDMETHODIMP_(ULONG) classname::Release()                                   \
 169   {                                                                           \
 170     wxLogRelease(_T(#classname), m_cRef);                                     \
 171                                                                               \
 172     if ( --m_cRef == wxAutoULong(0) ) {                                                    \
 173       delete this;                                                            \
 174       return 0;                                                               \
 175     }                                                                         \
 176     else                                                                      \
 177       return m_cRef;                                                          \
 178   }
 179
 180 // ============================================================================
 181 // Debugging support
 182 // ============================================================================
 183
 184 // VZ: I don't know it's not done for compilers other than VC++ but I leave it
 185 //     as is. Please note, though, that tracing OLE interface calls may be
 186 //     incredibly useful when debugging OLE programs.
 187 #if defined(__WXDEBUG__) && ( ( defined(__VISUALC__) && (__VISUALC__ >= 1000) ) || defined(__MWERKS__) )
 188 // ----------------------------------------------------------------------------
 189 // All OLE specific log functions have DebugTrace level (as LogTrace)
 190 // ----------------------------------------------------------------------------
 191
 192 // tries to translate riid into a symbolic name, if possible
 193 void wxLogQueryInterface(const wxChar *szInterface, REFIID riid);
 194
 195 // these functions print out the new value of reference counter
 196 void wxLogAddRef (const wxChar *szInterface, ULONG cRef);
 197 void wxLogRelease(const wxChar *szInterface, ULONG cRef);
 198
 199 #else   //!__WXDEBUG__
 200   #define   wxLogQueryInterface(szInterface, riid)
 201   #define   wxLogAddRef(szInterface, cRef)
 202   #define   wxLogRelease(szInterface, cRef)
 203 #endif  //__WXDEBUG__
 204
 205 // wrapper around BSTR type (by Vadim Zeitlin)
 206
 207 class WXDLLEXPORT wxBasicString
 208 {
 209 public:
 210     // ctors & dtor
 211     wxBasicString(const char *sz);
 212     wxBasicString(const wxString& str);
 213     ~wxBasicString();
 214
 215     void Init(const char* sz);
 216
 217     // accessors
 218     // just get the string
 219     operator BSTR() const { return m_wzBuf; }
 220     // retrieve a copy of our string - caller must SysFreeString() it later!
 221     BSTR Get() const { return SysAllocString(m_wzBuf); }
 222
 223 private:
 224     // @@@ not implemented (but should be)
 225     wxBasicString(const wxBasicString&);
 226     wxBasicString& operator=(const wxBasicString&);
 227
 228     OLECHAR *m_wzBuf;     // actual string
 229 };
 230
 231 #if wxUSE_VARIANT
 232 // Convert variants
 233 class WXDLLIMPEXP_FWD_BASE wxVariant;
 234
 235 WXDLLEXPORT bool wxConvertVariantToOle(const wxVariant& variant, VARIANTARG& oleVariant);
 236 WXDLLEXPORT bool wxConvertOleToVariant(const VARIANTARG& oleVariant, wxVariant& variant);
 237 #endif // wxUSE_VARIANT
 238
 239 // Convert string to Unicode
 240 WXDLLEXPORT BSTR wxConvertStringToOle(const wxString& str);
 241
 242 // Convert string from BSTR to wxString
 243 WXDLLEXPORT wxString wxConvertStringFromOle(BSTR bStr);
 244
 245 #else // !wxUSE_OLE
 246
 247 // ----------------------------------------------------------------------------
 248 // stub functions to avoid #if wxUSE_OLE in the main code
 249 // ----------------------------------------------------------------------------
 250
 251 inline bool wxOleInitialize() { return false; }
 252 inline void wxOleUninitialize() { }
 253
 254 #endif // wxUSE_OLE/!wxUSE_OLE
 255
 256 #endif  //_WX_OLEUTILS_H