src/osx/core/strconv_cf.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/osx/core/strconv_cf.cpp
   3 // Purpose:     Unicode conversion classes
   4 // Author:      David Elliott
   5 // Modified by:
   6 // Created:     2007-07-06
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) 2007 David Elliott
   9 // Licence:     wxWindows licence
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 // For compilers that support precompilation, includes "wx.h".
  13 #include "wx/wxprec.h"
  14
  15 #ifndef WX_PRECOMP
  16     #include "wx/string.h"
  17 #endif
  18
  19 #include "wx/strconv.h"
  20 #include "wx/fontmap.h"
  21
  22 #ifdef __DARWIN__
  23
  24 #include "wx/osx/core/private/strconv_cf.h"
  25 #include "wx/osx/core/cfref.h"
  26
  27
  28 // ============================================================================
  29 // CoreFoundation conversion classes
  30 // ============================================================================
  31
  32 /* Provide factory functions for unit tests.  Not in any header.  Do not
  33  * assume ABI compatibility even within a given wxWidgets release.
  34  */
  35
  36 #if wxUSE_FONTMAP
  37 WXDLLIMPEXP_BASE wxMBConv* new_wxMBConv_cf( const char* name)
  38 {
  39     wxMBConv_cf *result = new wxMBConv_cf(name);
  40     if(!result->IsOk())
  41     {
  42         delete result;
  43         return NULL;
  44     }
  45     else
  46         return result;
  47 }
  48 #endif // wxUSE_FONTMAP
  49
  50 WXDLLIMPEXP_BASE wxMBConv* new_wxMBConv_cf(wxFontEncoding encoding)
  51 {
  52     wxMBConv_cf *result = new wxMBConv_cf(encoding);
  53     if(!result->IsOk())
  54     {
  55         delete result;
  56         return NULL;
  57     }
  58     else
  59         return result;
  60 }
  61
  62 // Provide a constant for the wchat_t encoding used by the host platform.
  63 #ifdef WORDS_BIGENDIAN
  64     static const CFStringEncoding wxCFStringEncodingWcharT = kCFStringEncodingUTF32BE;
  65 #else
  66     static const CFStringEncoding wxCFStringEncodingWcharT = kCFStringEncodingUTF32LE;
  67 #endif
  68
  69     size_t wxMBConv_cf::ToWChar(wchar_t * dst, size_t dstSize, const char * src, size_t srcSize) const
  70     {
  71         wxCHECK(src, wxCONV_FAILED);
  72
  73         /* NOTE: This is wrong if the source encoding has an element size
  74          * other than char (e.g. it's kCFStringEncodingUnicode)
  75          * If the user specifies it, it's presumably right though.
  76          * Right now we don't support UTF-16 in anyway since wx can do a better job.
  77          */
  78         if(srcSize == wxNO_LEN)
  79             srcSize = strlen(src) + 1;
  80
  81         // First create the temporary CFString
  82         wxCFRef<CFStringRef> theString( CFStringCreateWithBytes (
  83                                                 NULL, //the allocator
  84                                                 (const UInt8*)src,
  85                                                 srcSize,
  86                                                 m_encoding,
  87                                                 false //no BOM/external representation
  88                                                 ));
  89
  90         if ( theString == NULL )
  91             return wxCONV_FAILED;
  92
  93         // Ensure that the string is in canonical composed form (NFC): this is
  94         // important because Darwin uses decomposed form (NFD) for e.g. file
  95         // names but we want to use NFC internally.
  96         wxCFRef<CFMutableStringRef>
  97             cfMutableString(CFStringCreateMutableCopy(NULL, 0, theString));
  98         CFStringNormalize(cfMutableString, kCFStringNormalizationFormC);
  99         theString = cfMutableString;
 100
 101         /* NOTE: The string content includes the NULL element if the source string did
 102          * That means we have to do nothing special because the destination will have
 103          * the NULL element iff the source did and the NULL element will be included
 104          * in the count iff it was included in the source count.
 105          */
 106
 107
 108 /* If we're compiling against Tiger headers we can support direct conversion
 109  * to UTF32.  If we are then run against a pre-Tiger system, the encoding
 110  * won't be available so we'll defer to the string->UTF-16->UTF-32 conversion.
 111  */
 112         if(CFStringIsEncodingAvailable(wxCFStringEncodingWcharT))
 113         {
 114             CFRange fullStringRange = CFRangeMake(0, CFStringGetLength(theString));
 115             CFIndex usedBufLen;
 116
 117             CFIndex charsConverted = CFStringGetBytes(
 118                     theString,
 119                     fullStringRange,
 120                     wxCFStringEncodingWcharT,
 121                     0,
 122                     false,
 123                     // if dstSize is 0 then pass NULL to get required length in usedBufLen
 124                     dstSize != 0?(UInt8*)dst:NULL,
 125                     dstSize * sizeof(wchar_t),
 126                     &usedBufLen);
 127
 128             if(charsConverted < CFStringGetLength(theString))
 129                 return wxCONV_FAILED;
 130
 131             /* usedBufLen is the number of bytes written, so we divide by
 132              * sizeof(wchar_t) to get the number of elements written.
 133              */
 134             wxASSERT( (usedBufLen % sizeof(wchar_t)) == 0 );
 135
 136             // CFStringGetBytes does exactly the right thing when buffer
 137             // pointer is NULL and returns the number of bytes required
 138             return usedBufLen / sizeof(wchar_t);
 139         }
 140         else
 141         {
 142             // NOTE: Includes NULL iff source did
 143             /* NOTE: This is an approximation.  The eventual UTF-32 will
 144              * possibly have less elements but certainly not more.
 145              */
 146             size_t returnSize = CFStringGetLength(theString);
 147
 148             if (dstSize == 0 || dst == NULL)
 149             {
 150                 return returnSize;
 151             }
 152
 153             // Convert the entire string.. too hard to figure out how many UTF-16 we'd need
 154             // for an undersized UTF-32 destination buffer.
 155             CFRange fullStringRange = CFRangeMake(0, CFStringGetLength(theString));
 156             UniChar *szUniCharBuffer = new UniChar[fullStringRange.length];
 157
 158             CFStringGetCharacters(theString, fullStringRange, szUniCharBuffer);
 159
 160             wxMBConvUTF16 converter;
 161             returnSize = converter.ToWChar( dst, dstSize, (const char*)szUniCharBuffer, fullStringRange.length );
 162             delete [] szUniCharBuffer;
 163
 164             return returnSize;
 165         }
 166         // NOTREACHED
 167     }
 168
 169     size_t wxMBConv_cf::FromWChar(char *dst, size_t dstSize, const wchar_t *src, size_t srcSize) const
 170     {
 171         wxCHECK(src, wxCONV_FAILED);
 172
 173         if(srcSize == wxNO_LEN)
 174             srcSize = wxStrlen(src) + 1;
 175
 176         // Temporary CFString
 177         wxCFRef<CFStringRef> theString;
 178
 179 /* If we're compiling against Tiger headers we can support direct conversion
 180  * from UTF32.  If we are then run against a pre-Tiger system, the encoding
 181  * won't be available so we'll defer to the UTF-32->UTF-16->string conversion.
 182  */
 183         if(CFStringIsEncodingAvailable(wxCFStringEncodingWcharT))
 184         {
 185             theString = wxCFRef<CFStringRef>(CFStringCreateWithBytes(
 186                     kCFAllocatorDefault,
 187                     (UInt8*)src,
 188                     srcSize * sizeof(wchar_t),
 189                     wxCFStringEncodingWcharT,
 190                     false));
 191         }
 192         else
 193         {
 194             wxMBConvUTF16 converter;
 195             size_t cbUniBuffer = converter.FromWChar( NULL, 0, src, srcSize );
 196             wxASSERT(cbUniBuffer % sizeof(UniChar));
 197
 198             // Will be free'd by kCFAllocatorMalloc when CFString is released
 199             UniChar *tmpUniBuffer = (UniChar*)malloc(cbUniBuffer);
 200
 201             cbUniBuffer = converter.FromWChar( (char*) tmpUniBuffer, cbUniBuffer, src, srcSize );
 202             wxASSERT(cbUniBuffer % sizeof(UniChar));
 203
 204             theString = wxCFRef<CFStringRef>(CFStringCreateWithCharactersNoCopy(
 205                         kCFAllocatorDefault,
 206                         tmpUniBuffer,
 207                         cbUniBuffer / sizeof(UniChar),
 208                         kCFAllocatorMalloc
 209                     ));
 210
 211         }
 212
 213         wxCHECK(theString != NULL, wxCONV_FAILED);
 214
 215         CFIndex usedBufLen;
 216
 217         CFIndex charsConverted = CFStringGetBytes(
 218                 theString,
 219                 CFRangeMake(0, CFStringGetLength(theString)),
 220                 m_encoding,
 221                 0, // FAIL on unconvertible characters
 222                 false, // not an external representation
 223                 (UInt8*)dst,
 224                 dstSize,
 225                 &usedBufLen
 226             );
 227
 228         // when dst is non-NULL, we check usedBufLen against dstSize as
 229         // CFStringGetBytes sometimes treats dst as being NULL when dstSize==0
 230         if( (charsConverted < CFStringGetLength(theString)) ||
 231                 (dst && (size_t) usedBufLen > dstSize) )
 232             return wxCONV_FAILED;
 233
 234         return usedBufLen;
 235     }
 236
 237 #endif // __DARWIN__
 238
 239