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(__WINDOWS__) && !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     int major,
  51         minor,
  52         build;
  53
  54     if ( sscanf(zlibVersion(), "%d.%d.%d", &major, &minor, &build) != 3 )
  55     {
  56         major =
  57         minor =
  58         build = 0;
  59     }
  60
  61     return wxVersionInfo("zlib", major, minor, build);
  62 }
  63
  64 /////////////////////////////////////////////////////////////////////////////
  65 // Zlib Class factory
  66
  67 IMPLEMENT_DYNAMIC_CLASS(wxZlibClassFactory, wxFilterClassFactory)
  68
  69 static wxZlibClassFactory g_wxZlibClassFactory;
  70
  71 wxZlibClassFactory::wxZlibClassFactory()
  72 {
  73     if (this == &g_wxZlibClassFactory)
  74         PushFront();
  75 }
  76
  77 const wxChar * const *
  78 wxZlibClassFactory::GetProtocols(wxStreamProtocolType type) const
  79 {
  80     static const wxChar *mimes[] = { wxT("application/x-deflate"), NULL };
  81     static const wxChar *encs[] =  { wxT("deflate"), NULL };
  82     static const wxChar *empty[] = { NULL };
  83
  84     switch (type) {
  85         case wxSTREAM_MIMETYPE:         return mimes;
  86         case wxSTREAM_ENCODING:         return encs;
  87         default:                        return empty;
  88     }
  89 }
  90
  91
  92 /////////////////////////////////////////////////////////////////////////////
  93 // Gzip Class factory
  94
  95 IMPLEMENT_DYNAMIC_CLASS(wxGzipClassFactory, wxFilterClassFactory)
  96
  97 static wxGzipClassFactory g_wxGzipClassFactory;
  98
  99 wxGzipClassFactory::wxGzipClassFactory()
 100 {
 101     if (this == &g_wxGzipClassFactory && wxZlibInputStream::CanHandleGZip())
 102         PushFront();
 103 }
 104
 105 const wxChar * const *
 106 wxGzipClassFactory::GetProtocols(wxStreamProtocolType type) const
 107 {
 108     static const wxChar *protos[] =
 109         { wxT("gzip"), NULL };
 110     static const wxChar *mimes[] =
 111         { wxT("application/gzip"), wxT("application/x-gzip"), NULL };
 112     static const wxChar *encs[] =
 113         { wxT("gzip"), NULL };
 114     static const wxChar *exts[] =
 115         { wxT(".gz"), wxT(".gzip"), NULL };
 116     static const wxChar *empty[] =
 117         { NULL };
 118
 119     switch (type) {
 120         case wxSTREAM_PROTOCOL: return protos;
 121         case wxSTREAM_MIMETYPE: return mimes;
 122         case wxSTREAM_ENCODING: return encs;
 123         case wxSTREAM_FILEEXT:  return exts;
 124         default:                return empty;
 125     }
 126 }
 127
 128
 129 //////////////////////
 130 // wxZlibInputStream
 131 //////////////////////
 132
 133 wxZlibInputStream::wxZlibInputStream(wxInputStream& stream, int flags)
 134   : wxFilterInputStream(stream)
 135 {
 136     Init(flags);
 137 }
 138
 139 wxZlibInputStream::wxZlibInputStream(wxInputStream *stream, int flags)
 140   : wxFilterInputStream(stream)
 141 {
 142     Init(flags);
 143 }
 144
 145 void wxZlibInputStream::Init(int flags)
 146 {
 147   m_inflate = NULL;
 148   m_z_buffer = new unsigned char[ZSTREAM_BUFFER_SIZE];
 149   m_z_size = ZSTREAM_BUFFER_SIZE;
 150   m_pos = 0;
 151
 152   // if gzip is asked for but not supported...
 153   if ((flags == wxZLIB_GZIP || flags == wxZLIB_AUTO) && !CanHandleGZip()) {
 154     if (flags == wxZLIB_AUTO) {
 155       // an error will come later if the input turns out not to be a zlib
 156       flags = wxZLIB_ZLIB;
 157     }
 158     else {
 159       wxLogError(_("Gzip not supported by this version of zlib"));
 160       m_lasterror = wxSTREAM_READ_ERROR;
 161       return;
 162     }
 163   }
 164
 165   if (m_z_buffer) {
 166     m_inflate = new z_stream_s;
 167
 168     if (m_inflate) {
 169       memset(m_inflate, 0, sizeof(z_stream_s));
 170
 171       // see zlib.h for documentation on windowBits
 172       int windowBits = MAX_WBITS;
 173       switch (flags) {
 174         case wxZLIB_NO_HEADER:  windowBits = -MAX_WBITS; break;
 175         case wxZLIB_ZLIB:       windowBits = MAX_WBITS; break;
 176         case wxZLIB_GZIP:       windowBits = MAX_WBITS | ZSTREAM_GZIP; break;
 177         case wxZLIB_AUTO:       windowBits = MAX_WBITS | ZSTREAM_AUTO; break;
 178         default:                wxFAIL_MSG(wxT("Invalid zlib flag"));
 179       }
 180
 181       if (inflateInit2(m_inflate, windowBits) == Z_OK)
 182         return;
 183     }
 184   }
 185
 186   wxLogError(_("Can't initialize zlib inflate stream."));
 187   m_lasterror = wxSTREAM_READ_ERROR;
 188 }
 189
 190 wxZlibInputStream::~wxZlibInputStream()
 191 {
 192   inflateEnd(m_inflate);
 193   delete m_inflate;
 194
 195   delete [] m_z_buffer;
 196 }
 197
 198 size_t wxZlibInputStream::OnSysRead(void *buffer, size_t size)
 199 {
 200   wxASSERT_MSG(m_inflate && m_z_buffer, wxT("Inflate stream not open"));
 201
 202   if (!m_inflate || !m_z_buffer)
 203     m_lasterror = wxSTREAM_READ_ERROR;
 204   if (!IsOk() || !size)
 205     return 0;
 206
 207   int err = Z_OK;
 208   m_inflate->next_out = (unsigned char *)buffer;
 209   m_inflate->avail_out = size;
 210
 211   while (err == Z_OK && m_inflate->avail_out > 0) {
 212     if (m_inflate->avail_in == 0 && m_parent_i_stream->IsOk()) {
 213       m_parent_i_stream->Read(m_z_buffer, m_z_size);
 214       m_inflate->next_in = m_z_buffer;
 215       m_inflate->avail_in = m_parent_i_stream->LastRead();
 216     }
 217     err = inflate(m_inflate, Z_SYNC_FLUSH);
 218   }
 219
 220   switch (err) {
 221     case Z_OK:
 222         break;
 223
 224     case Z_STREAM_END:
 225       if (m_inflate->avail_out) {
 226         // Unread any data taken from past the end of the deflate stream, so that
 227         // any additional data can be read from the underlying stream (the crc
 228         // in a gzip for example)
 229         if (m_inflate->avail_in) {
 230           m_parent_i_stream->Reset();
 231           m_parent_i_stream->Ungetch(m_inflate->next_in, m_inflate->avail_in);
 232           m_inflate->avail_in = 0;
 233         }
 234         m_lasterror = wxSTREAM_EOF;
 235       }
 236       break;
 237
 238     case Z_BUF_ERROR:
 239       // Indicates that zlib was expecting more data, but the parent stream
 240       // has none. Other than Eof the error will have been already reported
 241       // by the parent strean,
 242       m_lasterror = wxSTREAM_READ_ERROR;
 243       if (m_parent_i_stream->Eof())
 244       {
 245           wxLogError(_("Can't read inflate stream: unexpected EOF in underlying stream."));
 246       }
 247       break;
 248
 249     default:
 250       wxString msg(m_inflate->msg, *wxConvCurrent);
 251       if (!msg)
 252         msg = wxString::Format(_("zlib error %d"), err);
 253       wxLogError(_("Can't read from inflate stream: %s"), msg.c_str());
 254       m_lasterror = wxSTREAM_READ_ERROR;
 255   }
 256
 257   size -= m_inflate->avail_out;
 258   m_pos += size;
 259   return size;
 260 }
 261
 262 /* static */ bool wxZlibInputStream::CanHandleGZip()
 263 {
 264   const char *dot = strchr(zlibVersion(), '.');
 265   int major = atoi(zlibVersion());
 266   int minor = dot ? atoi(dot + 1) : 0;
 267   return major > 1 || (major == 1 && minor >= 2);
 268 }
 269
 270 bool wxZlibInputStream::SetDictionary(const char *data, const size_t datalen)
 271 {
 272     return (inflateSetDictionary(m_inflate, (Bytef*)data, datalen) == Z_OK);
 273 }
 274
 275 bool wxZlibInputStream::SetDictionary(const wxMemoryBuffer &buf)
 276 {
 277     return SetDictionary((char*)buf.GetData(), buf.GetDataLen());
 278 }
 279
 280
 281 //////////////////////
 282 // wxZlibOutputStream
 283 //////////////////////
 284
 285 wxZlibOutputStream::wxZlibOutputStream(wxOutputStream& stream,
 286                                        int level,
 287                                        int flags)
 288  : wxFilterOutputStream(stream)
 289 {
 290     Init(level, flags);
 291 }
 292
 293 wxZlibOutputStream::wxZlibOutputStream(wxOutputStream *stream,
 294                                        int level,
 295                                        int flags)
 296  : wxFilterOutputStream(stream)
 297 {
 298     Init(level, flags);
 299 }
 300
 301 void wxZlibOutputStream::Init(int level, int flags)
 302 {
 303   m_deflate = NULL;
 304   m_z_buffer = new unsigned char[ZSTREAM_BUFFER_SIZE];
 305   m_z_size = ZSTREAM_BUFFER_SIZE;
 306   m_pos = 0;
 307
 308   if ( level == -1 )
 309   {
 310     level = Z_DEFAULT_COMPRESSION;
 311   }
 312   else
 313   {
 314     wxASSERT_MSG(level >= 0 && level <= 9, wxT("wxZlibOutputStream compression level must be between 0 and 9!"));
 315   }
 316
 317   // if gzip is asked for but not supported...
 318   if (flags == wxZLIB_GZIP && !CanHandleGZip()) {
 319     wxLogError(_("Gzip not supported by this version of zlib"));
 320     m_lasterror = wxSTREAM_WRITE_ERROR;
 321     return;
 322   }
 323
 324   if (m_z_buffer) {
 325     m_deflate = new z_stream_s;
 326
 327     if (m_deflate) {
 328       memset(m_deflate, 0, sizeof(z_stream_s));
 329       m_deflate->next_out = m_z_buffer;
 330       m_deflate->avail_out = m_z_size;
 331
 332       // see zlib.h for documentation on windowBits
 333       int windowBits = MAX_WBITS;
 334       switch (flags) {
 335         case wxZLIB_NO_HEADER:  windowBits = -MAX_WBITS; break;
 336         case wxZLIB_ZLIB:       windowBits = MAX_WBITS; break;
 337         case wxZLIB_GZIP:       windowBits = MAX_WBITS | ZSTREAM_GZIP; break;
 338         default:                wxFAIL_MSG(wxT("Invalid zlib flag"));
 339       }
 340
 341       if (deflateInit2(m_deflate, level, Z_DEFLATED, windowBits,
 342                        8, Z_DEFAULT_STRATEGY) == Z_OK)
 343         return;
 344     }
 345   }
 346
 347   wxLogError(_("Can't initialize zlib deflate stream."));
 348   m_lasterror = wxSTREAM_WRITE_ERROR;
 349 }
 350
 351 bool wxZlibOutputStream::Close()
 352  {
 353   DoFlush(true);
 354    deflateEnd(m_deflate);
 355    wxDELETE(m_deflate);
 356    wxDELETEA(m_z_buffer);
 357
 358   return wxFilterOutputStream::Close() && IsOk();
 359  }
 360
 361 void wxZlibOutputStream::DoFlush(bool final)
 362 {
 363   if (!m_deflate || !m_z_buffer)
 364     m_lasterror = wxSTREAM_WRITE_ERROR;
 365   if (!IsOk())
 366     return;
 367
 368   int err = Z_OK;
 369   bool done = false;
 370
 371   while (err == Z_OK || err == Z_STREAM_END) {
 372     size_t len = m_z_size  - m_deflate->avail_out;
 373     if (len) {
 374       if (m_parent_o_stream->Write(m_z_buffer, len).LastWrite() != len) {
 375         m_lasterror = wxSTREAM_WRITE_ERROR;
 376         wxLogDebug(wxT("wxZlibOutputStream: Error writing to underlying stream"));
 377         break;
 378       }
 379       m_deflate->next_out = m_z_buffer;
 380       m_deflate->avail_out = m_z_size;
 381     }
 382
 383     if (done)
 384       break;
 385     err = deflate(m_deflate, final ? Z_FINISH : Z_FULL_FLUSH);
 386     done = m_deflate->avail_out != 0 || err == Z_STREAM_END;
 387   }
 388 }
 389
 390 size_t wxZlibOutputStream::OnSysWrite(const void *buffer, size_t size)
 391 {
 392   wxASSERT_MSG(m_deflate && m_z_buffer, wxT("Deflate stream not open"));
 393
 394   if (!m_deflate || !m_z_buffer)
 395   {
 396     // notice that this will make IsOk() test just below return false
 397     m_lasterror = wxSTREAM_WRITE_ERROR;
 398   }
 399
 400   if (!IsOk() || !size)
 401     return 0;
 402
 403   int err = Z_OK;
 404   m_deflate->next_in = (unsigned char *)buffer;
 405   m_deflate->avail_in = size;
 406
 407   while (err == Z_OK && m_deflate->avail_in > 0) {
 408     if (m_deflate->avail_out == 0) {
 409       m_parent_o_stream->Write(m_z_buffer, m_z_size);
 410       if (m_parent_o_stream->LastWrite() != m_z_size) {
 411         m_lasterror = wxSTREAM_WRITE_ERROR;
 412         wxLogDebug(wxT("wxZlibOutputStream: Error writing to underlying stream"));
 413         break;
 414       }
 415
 416       m_deflate->next_out = m_z_buffer;
 417       m_deflate->avail_out = m_z_size;
 418     }
 419
 420     err = deflate(m_deflate, Z_NO_FLUSH);
 421   }
 422
 423   if (err != Z_OK) {
 424     m_lasterror = wxSTREAM_WRITE_ERROR;
 425     wxString msg(m_deflate->msg, *wxConvCurrent);
 426     if (!msg)
 427       msg = wxString::Format(_("zlib error %d"), err);
 428     wxLogError(_("Can't write to deflate stream: %s"), msg.c_str());
 429   }
 430
 431   size -= m_deflate->avail_in;
 432   m_pos += size;
 433   return size;
 434 }
 435
 436 /* static */ bool wxZlibOutputStream::CanHandleGZip()
 437 {
 438   return wxZlibInputStream::CanHandleGZip();
 439 }
 440
 441 bool wxZlibOutputStream::SetDictionary(const char *data, const size_t datalen)
 442 {
 443     return (deflateSetDictionary(m_deflate, (Bytef*)data, datalen) == Z_OK);
 444 }
 445
 446 bool wxZlibOutputStream::SetDictionary(const wxMemoryBuffer &buf)
 447 {
 448     return SetDictionary((char*)buf.GetData(), buf.GetDataLen());
 449 }
 450
 451 #endif
 452   // wxUSE_ZLIB && wxUSE_STREAMS