src/common/textbuf.cpp

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/common/textbuf.cpp
   3 // Purpose:     implementation of wxTextBuffer class
   4 // Created:     14.11.01
   5 // Author:      Morten Hanssen, Vadim Zeitlin
   6 // Copyright:   (c) 1998-2001 wxWidgets team
   7 // Licence:     wxWindows licence
   8 ///////////////////////////////////////////////////////////////////////////////
   9
  10 // ============================================================================
  11 // headers
  12 // ============================================================================
  13
  14 #if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
  15     #pragma implementation "textbuf.h"
  16 #endif
  17
  18 #include  "wx/wxprec.h"
  19
  20 #ifdef __BORLANDC__
  21     #pragma hdrstop
  22 #endif  //__BORLANDC__
  23
  24 #ifndef WX_PRECOMP
  25     #include  "wx/string.h"
  26     #include  "wx/intl.h"
  27     #include  "wx/log.h"
  28 #endif
  29
  30 #include "wx/textbuf.h"
  31
  32 // ============================================================================
  33 // wxTextBuffer class implementation
  34 // ============================================================================
  35
  36 // ----------------------------------------------------------------------------
  37 // static methods (always compiled in)
  38 // ----------------------------------------------------------------------------
  39
  40 // default type is the native one
  41 // the native type under Mac OS X is:
  42 //   - Unix when compiling with the Apple Developer Tools (__UNIX__)
  43 //   - Mac when compiling with CodeWarrior (__WXMAC__)
  44
  45 const wxTextFileType wxTextBuffer::typeDefault =
  46 #if defined(__WINDOWS__) || defined(__DOS__) || defined(__PALMOS__)
  47   wxTextFileType_Dos;
  48 #elif defined(__UNIX__)
  49   wxTextFileType_Unix;
  50 #elif defined(__WXMAC__)
  51   wxTextFileType_Mac;
  52 #elif defined(__WXPM__)
  53   wxTextFileType_Os2;
  54 #else
  55   wxTextFileType_None;
  56   #error  "wxTextBuffer: unsupported platform."
  57 #endif
  58
  59 const wxChar *wxTextBuffer::GetEOL(wxTextFileType type)
  60 {
  61     switch ( type ) {
  62         default:
  63             wxFAIL_MSG(wxT("bad buffer type in wxTextBuffer::GetEOL."));
  64             // fall through nevertheless - we must return something...
  65
  66         case wxTextFileType_None: return wxEmptyString;
  67         case wxTextFileType_Unix: return wxT("\n");
  68         case wxTextFileType_Dos:  return wxT("\r\n");
  69         case wxTextFileType_Mac:  return wxT("\r");
  70     }
  71 }
  72
  73 wxString wxTextBuffer::Translate(const wxString& text, wxTextFileType type)
  74 {
  75     // don't do anything if there is nothing to do
  76     if ( type == wxTextFileType_None )
  77         return text;
  78
  79     // nor if it is empty
  80     if ( text.empty() )
  81         return text;
  82
  83     wxString eol = GetEOL(type), result;
  84
  85     // optimization: we know that the length of the new string will be about
  86     // the same as the length of the old one, so prealloc memory to aviod
  87     // unnecessary relocations
  88     result.Alloc(text.Len());
  89
  90     wxChar chLast = 0;
  91     for ( const wxChar *pc = text.c_str(); *pc; pc++ )
  92     {
  93         wxChar ch = *pc;
  94         switch ( ch ) {
  95             case _T('\n'):
  96                 // Dos/Unix line termination
  97                 result += eol;
  98                 chLast = 0;
  99                 break;
 100
 101             case _T('\r'):
 102                 if ( chLast == _T('\r') ) {
 103                     // Mac empty line
 104                     result += eol;
 105                 }
 106                 else {
 107                     // just remember it: we don't know whether it is just "\r"
 108                     // or "\r\n" yet
 109                     chLast = _T('\r');
 110                 }
 111                 break;
 112
 113             default:
 114                 if ( chLast == _T('\r') ) {
 115                     // Mac line termination
 116                     result += eol;
 117
 118                     // reset chLast to avoid inserting another eol before the
 119                     // next character
 120                     chLast = 0;
 121                 }
 122
 123                 // add to the current line
 124                 result += ch;
 125         }
 126     }
 127
 128     if ( chLast ) {
 129         // trailing '\r'
 130         result += eol;
 131     }
 132
 133     return result;
 134 }
 135
 136 #if wxUSE_TEXTBUFFER
 137
 138 // ----------------------------------------------------------------------------
 139 // ctors & dtor
 140 // ----------------------------------------------------------------------------
 141
 142 wxTextBuffer::wxTextBuffer(const wxString& strBufferName)
 143             : m_strBufferName(strBufferName)
 144 {
 145     m_nCurLine = 0;
 146     m_isOpened = false;
 147 }
 148
 149 wxTextBuffer::~wxTextBuffer()
 150 {
 151     // required here for Darwin
 152 }
 153
 154 // ----------------------------------------------------------------------------
 155 // buffer operations
 156 // ----------------------------------------------------------------------------
 157
 158 bool wxTextBuffer::Exists() const
 159 {
 160     return OnExists();
 161 }
 162
 163 bool wxTextBuffer::Create(const wxString& strBufferName)
 164 {
 165     m_strBufferName = strBufferName;
 166
 167     return Create();
 168 }
 169
 170 bool wxTextBuffer::Create()
 171 {
 172     // buffer name must be either given in ctor or in Create(const wxString&)
 173     wxASSERT( !m_strBufferName.empty() );
 174
 175     // if the buffer already exists do nothing
 176     if ( Exists() ) return false;
 177
 178     if ( !OnOpen(m_strBufferName, WriteAccess) )
 179         return false;
 180
 181     OnClose();
 182     return true;
 183 }
 184
 185 bool wxTextBuffer::Open(const wxString& strBufferName, wxMBConv& conv)
 186 {
 187     m_strBufferName = strBufferName;
 188
 189     return Open(conv);
 190 }
 191
 192 bool wxTextBuffer::Open(wxMBConv& conv)
 193 {
 194     // buffer name must be either given in ctor or in Open(const wxString&)
 195     wxASSERT( !m_strBufferName.empty() );
 196
 197     // open buffer in read-only mode
 198     if ( !OnOpen(m_strBufferName, ReadAccess) )
 199         return false;
 200
 201     // read buffer into memory
 202     m_isOpened = OnRead(conv);
 203
 204     OnClose();
 205
 206     return m_isOpened;
 207 }
 208
 209 // analyse some lines of the buffer trying to guess it's type.
 210 // if it fails, it assumes the native type for our platform.
 211 wxTextFileType wxTextBuffer::GuessType() const
 212 {
 213     wxASSERT( IsOpened() );
 214
 215     // scan the buffer lines
 216     size_t nUnix = 0,     // number of '\n's alone
 217            nDos  = 0,     // number of '\r\n'
 218            nMac  = 0;     // number of '\r's
 219
 220     // we take MAX_LINES_SCAN in the beginning, middle and the end of buffer
 221     #define MAX_LINES_SCAN    (10)
 222     size_t nCount = m_aLines.Count() / 3,
 223         nScan =  nCount > 3*MAX_LINES_SCAN ? MAX_LINES_SCAN : nCount / 3;
 224
 225     #define   AnalyseLine(n)              \
 226         switch ( m_aTypes[n] ) {            \
 227             case wxTextFileType_Unix: nUnix++; break;   \
 228             case wxTextFileType_Dos:  nDos++;  break;   \
 229             case wxTextFileType_Mac:  nMac++;  break;   \
 230             default: wxFAIL_MSG(_("unknown line terminator")); \
 231         }
 232
 233     size_t n;
 234     for ( n = 0; n < nScan; n++ )     // the beginning
 235         AnalyseLine(n);
 236     for ( n = (nCount - nScan)/2; n < (nCount + nScan)/2; n++ )
 237         AnalyseLine(n);
 238     for ( n = nCount - nScan; n < nCount; n++ )
 239         AnalyseLine(n);
 240
 241     #undef   AnalyseLine
 242
 243     // interpret the results (FIXME far from being even 50% fool proof)
 244     if ( nScan > 0 && nDos + nUnix + nMac == 0 ) {
 245         // no newlines at all
 246         wxLogWarning(_("'%s' is probably a binary buffer."), m_strBufferName.c_str());
 247     }
 248     else {
 249         #define   GREATER_OF(t1, t2) n##t1 == n##t2 ? typeDefault               \
 250                                                 : n##t1 > n##t2             \
 251                                                     ? wxTextFileType_##t1   \
 252                                                     : wxTextFileType_##t2
 253
 254         // Watcom C++ doesn't seem to be able to handle the macro
 255         // VS: Watcom 11 doesn't have a problem...
 256 #if !(defined(__WATCOMC__) && (__WATCOMC__ < 1100))
 257         if ( nDos > nUnix )
 258             return GREATER_OF(Dos, Mac);
 259         else if ( nDos < nUnix )
 260             return GREATER_OF(Unix, Mac);
 261         else {
 262             // nDos == nUnix
 263             return nMac > nDos ? wxTextFileType_Mac : typeDefault;
 264         }
 265 #endif // __WATCOMC__
 266
 267         #undef    GREATER_OF
 268     }
 269
 270     return typeDefault;
 271 }
 272
 273
 274 bool wxTextBuffer::Close()
 275 {
 276     m_aTypes.Clear();
 277     m_aLines.Clear();
 278     m_nCurLine = 0;
 279     m_isOpened = false;
 280
 281     return true;
 282 }
 283
 284 bool wxTextBuffer::Write(wxTextFileType typeNew, wxMBConv& conv)
 285 {
 286     return OnWrite(typeNew, conv);
 287 }
 288
 289 #endif // wxUSE_TEXTBUFFER
 290