src/common/zstream.cpp

   1 //////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/common/zstream.cpp
   3 // Purpose:     Compressed stream classes
   4 // Author:      Guilhem Lavaux
   5 // Modified by: Mike Wetherell
   6 // Created:     11/07/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Guilhem Lavaux
   9 // Licence:     wxWindows licence
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 // For compilers that support precompilation, includes "wx.h".
  13 #include "wx/wxprec.h"
  14
  15 #ifdef __BORLANDC__
  16     #pragma hdrstop
  17 #endif
  18
  19 #if wxUSE_ZLIB && wxUSE_STREAMS
  20
  21 #include "wx/zstream.h"
  22 #include "wx/versioninfo.h"
  23
  24 #ifndef WX_PRECOMP
  25     #include "wx/intl.h"
  26     #include "wx/log.h"
  27     #include "wx/utils.h"
  28 #endif
  29
  30
  31 // normally, the compiler options should contain -I../zlib, but it is
  32 // apparently not the case for all MSW makefiles and so, unless we use
  33 // configure (which defines __WX_SETUP_H__) or it is explicitly overridden by
  34 // the user (who can define wxUSE_ZLIB_H_IN_PATH), we hardcode the path here
  35 #if defined(__WXMSW__) && !defined(__WX_SETUP_H__) && !defined(wxUSE_ZLIB_H_IN_PATH)
  36     #include "../zlib/zlib.h"
  37 #else
  38     #include "zlib.h"
  39 #endif
  40
  41 enum {
  42     ZSTREAM_BUFFER_SIZE = 16384,
  43     ZSTREAM_GZIP        = 0x10,     // gzip header
  44     ZSTREAM_AUTO        = 0x20      // auto detect between gzip and zlib
  45 };
  46
  47
  48 wxVersionInfo wxGetZlibVersionInfo()
  49 {
  50     return wxVersionInfo("zlib",
  51                          ZLIB_VERNUM >> 12,
  52                          (ZLIB_VERNUM >> 8) & 0x0F,
  53                          (ZLIB_VERNUM & 0xFF) / 0x10);
  54 }
  55
  56 /////////////////////////////////////////////////////////////////////////////
  57 // Zlib Class factory
  58
  59 IMPLEMENT_DYNAMIC_CLASS(wxZlibClassFactory, wxFilterClassFactory)
  60
  61 static wxZlibClassFactory g_wxZlibClassFactory;
  62
  63 wxZlibClassFactory::wxZlibClassFactory()
  64 {
  65     if (this == &g_wxZlibClassFactory)
  66         PushFront();
  67 }
  68
  69 const wxChar * const *
  70 wxZlibClassFactory::GetProtocols(wxStreamProtocolType type) const
  71 {
  72     static const wxChar *mimes[] = { wxT("application/x-deflate"), NULL };
  73     static const wxChar *encs[] =  { wxT("deflate"), NULL };
  74     static const wxChar *empty[] = { NULL };
  75
  76     switch (type) {
  77         case wxSTREAM_MIMETYPE:         return mimes;
  78         case wxSTREAM_ENCODING:         return encs;
  79         default:                        return empty;
  80     }
  81 }
  82
  83
  84 /////////////////////////////////////////////////////////////////////////////
  85 // Gzip Class factory
  86
  87 IMPLEMENT_DYNAMIC_CLASS(wxGzipClassFactory, wxFilterClassFactory)
  88
  89 static wxGzipClassFactory g_wxGzipClassFactory;
  90
  91 wxGzipClassFactory::wxGzipClassFactory()
  92 {
  93     if (this == &g_wxGzipClassFactory && wxZlibInputStream::CanHandleGZip())
  94         PushFront();
  95 }
  96
  97 const wxChar * const *
  98 wxGzipClassFactory::GetProtocols(wxStreamProtocolType type) const
  99 {
 100     static const wxChar *protos[] =
 101         { wxT("gzip"), NULL };
 102     static const wxChar *mimes[] =
 103         { wxT("application/gzip"), wxT("application/x-gzip"), NULL };
 104     static const wxChar *encs[] =
 105         { wxT("gzip"), NULL };
 106     static const wxChar *exts[] =
 107         { wxT(".gz"), wxT(".gzip"), NULL };
 108     static const wxChar *empty[] =
 109         { NULL };
 110
 111     switch (type) {
 112         case wxSTREAM_PROTOCOL: return protos;
 113         case wxSTREAM_MIMETYPE: return mimes;
 114         case wxSTREAM_ENCODING: return encs;
 115         case wxSTREAM_FILEEXT:  return exts;
 116         default:                return empty;
 117     }
 118 }
 119
 120
 121 //////////////////////
 122 // wxZlibInputStream
 123 //////////////////////
 124
 125 wxZlibInputStream::wxZlibInputStream(wxInputStream& stream, int flags)
 126   : wxFilterInputStream(stream)
 127 {
 128     Init(flags);
 129 }
 130
 131 wxZlibInputStream::wxZlibInputStream(wxInputStream *stream, int flags)
 132   : wxFilterInputStream(stream)
 133 {
 134     Init(flags);
 135 }
 136
 137 void wxZlibInputStream::Init(int flags)
 138 {
 139   m_inflate = NULL;
 140   m_z_buffer = new unsigned char[ZSTREAM_BUFFER_SIZE];
 141   m_z_size = ZSTREAM_BUFFER_SIZE;
 142   m_pos = 0;
 143
 144   // if gzip is asked for but not supported...
 145   if ((flags == wxZLIB_GZIP || flags == wxZLIB_AUTO) && !CanHandleGZip()) {
 146     if (flags == wxZLIB_AUTO) {
 147       // an error will come later if the input turns out not to be a zlib
 148       flags = wxZLIB_ZLIB;
 149     }
 150     else {
 151       wxLogError(_("Gzip not supported by this version of zlib"));
 152       m_lasterror = wxSTREAM_READ_ERROR;
 153       return;
 154     }
 155   }
 156
 157   if (m_z_buffer) {
 158     m_inflate = new z_stream_s;
 159
 160     if (m_inflate) {
 161       memset(m_inflate, 0, sizeof(z_stream_s));
 162
 163       // see zlib.h for documentation on windowBits
 164       int windowBits = MAX_WBITS;
 165       switch (flags) {
 166         case wxZLIB_NO_HEADER:  windowBits = -MAX_WBITS; break;
 167         case wxZLIB_ZLIB:       windowBits = MAX_WBITS; break;
 168         case wxZLIB_GZIP:       windowBits = MAX_WBITS | ZSTREAM_GZIP; break;
 169         case wxZLIB_AUTO:       windowBits = MAX_WBITS | ZSTREAM_AUTO; break;
 170         default:                wxFAIL_MSG(wxT("Invalid zlib flag"));
 171       }
 172
 173       if (inflateInit2(m_inflate, windowBits) == Z_OK)
 174         return;
 175     }
 176   }
 177
 178   wxLogError(_("Can't initialize zlib inflate stream."));
 179   m_lasterror = wxSTREAM_READ_ERROR;
 180 }
 181
 182 wxZlibInputStream::~wxZlibInputStream()
 183 {
 184   inflateEnd(m_inflate);
 185   delete m_inflate;
 186
 187   delete [] m_z_buffer;
 188 }
 189
 190 size_t wxZlibInputStream::OnSysRead(void *buffer, size_t size)
 191 {
 192   wxASSERT_MSG(m_inflate && m_z_buffer, wxT("Inflate stream not open"));
 193
 194   if (!m_inflate || !m_z_buffer)
 195     m_lasterror = wxSTREAM_READ_ERROR;
 196   if (!IsOk() || !size)
 197     return 0;
 198
 199   int err = Z_OK;
 200   m_inflate->next_out = (unsigned char *)buffer;
 201   m_inflate->avail_out = size;
 202
 203   while (err == Z_OK && m_inflate->avail_out > 0) {
 204     if (m_inflate->avail_in == 0 && m_parent_i_stream->IsOk()) {
 205       m_parent_i_stream->Read(m_z_buffer, m_z_size);
 206       m_inflate->next_in = m_z_buffer;
 207       m_inflate->avail_in = m_parent_i_stream->LastRead();
 208     }
 209     err = inflate(m_inflate, Z_SYNC_FLUSH);
 210   }
 211
 212   switch (err) {
 213     case Z_OK:
 214         break;
 215
 216     case Z_STREAM_END:
 217       if (m_inflate->avail_out) {
 218         // Unread any data taken from past the end of the deflate stream, so that
 219         // any additional data can be read from the underlying stream (the crc
 220         // in a gzip for example)
 221         if (m_inflate->avail_in) {
 222           m_parent_i_stream->Reset();
 223           m_parent_i_stream->Ungetch(m_inflate->next_in, m_inflate->avail_in);
 224           m_inflate->avail_in = 0;
 225         }
 226         m_lasterror = wxSTREAM_EOF;
 227       }
 228       break;
 229
 230     case Z_BUF_ERROR:
 231       // Indicates that zlib was expecting more data, but the parent stream
 232       // has none. Other than Eof the error will have been already reported
 233       // by the parent strean,
 234       m_lasterror = wxSTREAM_READ_ERROR;
 235       if (m_parent_i_stream->Eof())
 236       {
 237           wxLogError(_("Can't read inflate stream: unexpected EOF in underlying stream."));
 238       }
 239       break;
 240
 241     default:
 242       wxString msg(m_inflate->msg, *wxConvCurrent);
 243       if (!msg)
 244         msg = wxString::Format(_("zlib error %d"), err);
 245       wxLogError(_("Can't read from inflate stream: %s"), msg.c_str());
 246       m_lasterror = wxSTREAM_READ_ERROR;
 247   }
 248
 249   size -= m_inflate->avail_out;
 250   m_pos += size;
 251   return size;
 252 }
 253
 254 /* static */ bool wxZlibInputStream::CanHandleGZip()
 255 {
 256   const char *dot = strchr(zlibVersion(), '.');
 257   int major = atoi(zlibVersion());
 258   int minor = dot ? atoi(dot + 1) : 0;
 259   return major > 1 || (major == 1 && minor >= 2);
 260 }
 261
 262 bool wxZlibInputStream::SetDictionary(const char *data, const size_t datalen)
 263 {
 264     return (inflateSetDictionary(m_inflate, (Bytef*)data, datalen) == Z_OK);
 265 }
 266
 267 bool wxZlibInputStream::SetDictionary(const wxMemoryBuffer &buf)
 268 {
 269     return SetDictionary((char*)buf.GetData(), buf.GetDataLen());
 270 }
 271
 272
 273 //////////////////////
 274 // wxZlibOutputStream
 275 //////////////////////
 276
 277 wxZlibOutputStream::wxZlibOutputStream(wxOutputStream& stream,
 278                                        int level,
 279                                        int flags)
 280  : wxFilterOutputStream(stream)
 281 {
 282     Init(level, flags);
 283 }
 284
 285 wxZlibOutputStream::wxZlibOutputStream(wxOutputStream *stream,
 286                                        int level,
 287                                        int flags)
 288  : wxFilterOutputStream(stream)
 289 {
 290     Init(level, flags);
 291 }
 292
 293 void wxZlibOutputStream::Init(int level, int flags)
 294 {
 295   m_deflate = NULL;
 296   m_z_buffer = new unsigned char[ZSTREAM_BUFFER_SIZE];
 297   m_z_size = ZSTREAM_BUFFER_SIZE;
 298   m_pos = 0;
 299
 300   if ( level == -1 )
 301   {
 302     level = Z_DEFAULT_COMPRESSION;
 303   }
 304   else
 305   {
 306     wxASSERT_MSG(level >= 0 && level <= 9, wxT("wxZlibOutputStream compression level must be between 0 and 9!"));
 307   }
 308
 309   // if gzip is asked for but not supported...
 310   if (flags == wxZLIB_GZIP && !CanHandleGZip()) {
 311     wxLogError(_("Gzip not supported by this version of zlib"));
 312     m_lasterror = wxSTREAM_WRITE_ERROR;
 313     return;
 314   }
 315
 316   if (m_z_buffer) {
 317     m_deflate = new z_stream_s;
 318
 319     if (m_deflate) {
 320       memset(m_deflate, 0, sizeof(z_stream_s));
 321       m_deflate->next_out = m_z_buffer;
 322       m_deflate->avail_out = m_z_size;
 323
 324       // see zlib.h for documentation on windowBits
 325       int windowBits = MAX_WBITS;
 326       switch (flags) {
 327         case wxZLIB_NO_HEADER:  windowBits = -MAX_WBITS; break;
 328         case wxZLIB_ZLIB:       windowBits = MAX_WBITS; break;
 329         case wxZLIB_GZIP:       windowBits = MAX_WBITS | ZSTREAM_GZIP; break;
 330         default:                wxFAIL_MSG(wxT("Invalid zlib flag"));
 331       }
 332
 333       if (deflateInit2(m_deflate, level, Z_DEFLATED, windowBits,
 334                        8, Z_DEFAULT_STRATEGY) == Z_OK)
 335         return;
 336     }
 337   }
 338
 339   wxLogError(_("Can't initialize zlib deflate stream."));
 340   m_lasterror = wxSTREAM_WRITE_ERROR;
 341 }
 342
 343 bool wxZlibOutputStream::Close()
 344  {
 345   DoFlush(true);
 346    deflateEnd(m_deflate);
 347    wxDELETE(m_deflate);
 348    wxDELETEA(m_z_buffer);
 349
 350   return wxFilterOutputStream::Close() && IsOk();
 351  }
 352
 353 void wxZlibOutputStream::DoFlush(bool final)
 354 {
 355   if (!m_deflate || !m_z_buffer)
 356     m_lasterror = wxSTREAM_WRITE_ERROR;
 357   if (!IsOk())
 358     return;
 359
 360   int err = Z_OK;
 361   bool done = false;
 362
 363   while (err == Z_OK || err == Z_STREAM_END) {
 364     size_t len = m_z_size  - m_deflate->avail_out;
 365     if (len) {
 366       if (m_parent_o_stream->Write(m_z_buffer, len).LastWrite() != len) {
 367         m_lasterror = wxSTREAM_WRITE_ERROR;
 368         wxLogDebug(wxT("wxZlibOutputStream: Error writing to underlying stream"));
 369         break;
 370       }
 371       m_deflate->next_out = m_z_buffer;
 372       m_deflate->avail_out = m_z_size;
 373     }
 374
 375     if (done)
 376       break;
 377     err = deflate(m_deflate, final ? Z_FINISH : Z_FULL_FLUSH);
 378     done = m_deflate->avail_out != 0 || err == Z_STREAM_END;
 379   }
 380 }
 381
 382 size_t wxZlibOutputStream::OnSysWrite(const void *buffer, size_t size)
 383 {
 384   wxASSERT_MSG(m_deflate && m_z_buffer, wxT("Deflate stream not open"));
 385
 386   if (!m_deflate || !m_z_buffer)
 387   {
 388     // notice that this will make IsOk() test just below return false
 389     m_lasterror = wxSTREAM_WRITE_ERROR;
 390   }
 391
 392   if (!IsOk() || !size)
 393     return 0;
 394
 395   int err = Z_OK;
 396   m_deflate->next_in = (unsigned char *)buffer;
 397   m_deflate->avail_in = size;
 398
 399   while (err == Z_OK && m_deflate->avail_in > 0) {
 400     if (m_deflate->avail_out == 0) {
 401       m_parent_o_stream->Write(m_z_buffer, m_z_size);
 402       if (m_parent_o_stream->LastWrite() != m_z_size) {
 403         m_lasterror = wxSTREAM_WRITE_ERROR;
 404         wxLogDebug(wxT("wxZlibOutputStream: Error writing to underlying stream"));
 405         break;
 406       }
 407
 408       m_deflate->next_out = m_z_buffer;
 409       m_deflate->avail_out = m_z_size;
 410     }
 411
 412     err = deflate(m_deflate, Z_NO_FLUSH);
 413   }
 414
 415   if (err != Z_OK) {
 416     m_lasterror = wxSTREAM_WRITE_ERROR;
 417     wxString msg(m_deflate->msg, *wxConvCurrent);
 418     if (!msg)
 419       msg = wxString::Format(_("zlib error %d"), err);
 420     wxLogError(_("Can't write to deflate stream: %s"), msg.c_str());
 421   }
 422
 423   size -= m_deflate->avail_in;
 424   m_pos += size;
 425   return size;
 426 }
 427
 428 /* static */ bool wxZlibOutputStream::CanHandleGZip()
 429 {
 430   return wxZlibInputStream::CanHandleGZip();
 431 }
 432
 433 bool wxZlibOutputStream::SetDictionary(const char *data, const size_t datalen)
 434 {
 435     return (deflateSetDictionary(m_deflate, (Bytef*)data, datalen) == Z_OK);
 436 }
 437
 438 bool wxZlibOutputStream::SetDictionary(const wxMemoryBuffer &buf)
 439 {
 440     return SetDictionary((char*)buf.GetData(), buf.GetDataLen());
 441 }
 442
 443 #endif
 444   // wxUSE_ZLIB && wxUSE_STREAMS