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 // Copyright:   (c) Guilhem Lavaux
   8 // Licence:     wxWindows licence
   9 /////////////////////////////////////////////////////////////////////////////
  10
  11 // For compilers that support precompilation, includes "wx.h".
  12 #include "wx/wxprec.h"
  13
  14 #ifdef __BORLANDC__
  15     #pragma hdrstop
  16 #endif
  17
  18 #if wxUSE_ZLIB && wxUSE_STREAMS
  19
  20 #include "wx/zstream.h"
  21 #include "wx/versioninfo.h"
  22
  23 #ifndef WX_PRECOMP
  24     #include "wx/intl.h"
  25     #include "wx/log.h"
  26     #include "wx/utils.h"
  27 #endif
  28
  29
  30 // normally, the compiler options should contain -I../zlib, but it is
  31 // apparently not the case for all MSW makefiles and so, unless we use
  32 // configure (which defines __WX_SETUP_H__) or it is explicitly overridden by
  33 // the user (who can define wxUSE_ZLIB_H_IN_PATH), we hardcode the path here
  34 #if defined(__WINDOWS__) && !defined(__WX_SETUP_H__) && !defined(wxUSE_ZLIB_H_IN_PATH)
  35     #include "../zlib/zlib.h"
  36 #else
  37     #include "zlib.h"
  38 #endif
  39
  40 enum {
  41     ZSTREAM_BUFFER_SIZE = 16384,
  42     ZSTREAM_GZIP        = 0x10,     // gzip header
  43     ZSTREAM_AUTO        = 0x20      // auto detect between gzip and zlib
  44 };
  45
  46
  47 wxVersionInfo wxGetZlibVersionInfo()
  48 {
  49     int major,
  50         minor,
  51         build;
  52
  53     if ( sscanf(zlibVersion(), "%d.%d.%d", &major, &minor, &build) != 3 )
  54     {
  55         major =
  56         minor =
  57         build = 0;
  58     }
  59
  60     return wxVersionInfo("zlib", major, minor, build);
  61 }
  62
  63 /////////////////////////////////////////////////////////////////////////////
  64 // Zlib Class factory
  65
  66 IMPLEMENT_DYNAMIC_CLASS(wxZlibClassFactory, wxFilterClassFactory)
  67
  68 static wxZlibClassFactory g_wxZlibClassFactory;
  69
  70 wxZlibClassFactory::wxZlibClassFactory()
  71 {
  72     if (this == &g_wxZlibClassFactory)
  73         PushFront();
  74 }
  75
  76 const wxChar * const *
  77 wxZlibClassFactory::GetProtocols(wxStreamProtocolType type) const
  78 {
  79     static const wxChar *mimes[] = { wxT("application/x-deflate"), NULL };
  80     static const wxChar *encs[] =  { wxT("deflate"), NULL };
  81     static const wxChar *empty[] = { NULL };
  82
  83     switch (type) {
  84         case wxSTREAM_MIMETYPE:         return mimes;
  85         case wxSTREAM_ENCODING:         return encs;
  86         default:                        return empty;
  87     }
  88 }
  89
  90
  91 /////////////////////////////////////////////////////////////////////////////
  92 // Gzip Class factory
  93
  94 IMPLEMENT_DYNAMIC_CLASS(wxGzipClassFactory, wxFilterClassFactory)
  95
  96 static wxGzipClassFactory g_wxGzipClassFactory;
  97
  98 wxGzipClassFactory::wxGzipClassFactory()
  99 {
 100     if (this == &g_wxGzipClassFactory && wxZlibInputStream::CanHandleGZip())
 101         PushFront();
 102 }
 103
 104 const wxChar * const *
 105 wxGzipClassFactory::GetProtocols(wxStreamProtocolType type) const
 106 {
 107     static const wxChar *protos[] =
 108         { wxT("gzip"), NULL };
 109     static const wxChar *mimes[] =
 110         { wxT("application/gzip"), wxT("application/x-gzip"), NULL };
 111     static const wxChar *encs[] =
 112         { wxT("gzip"), NULL };
 113     static const wxChar *exts[] =
 114         { wxT(".gz"), wxT(".gzip"), NULL };
 115     static const wxChar *empty[] =
 116         { NULL };
 117
 118     switch (type) {
 119         case wxSTREAM_PROTOCOL: return protos;
 120         case wxSTREAM_MIMETYPE: return mimes;
 121         case wxSTREAM_ENCODING: return encs;
 122         case wxSTREAM_FILEEXT:  return exts;
 123         default:                return empty;
 124     }
 125 }
 126
 127
 128 //////////////////////
 129 // wxZlibInputStream
 130 //////////////////////
 131
 132 wxZlibInputStream::wxZlibInputStream(wxInputStream& stream, int flags)
 133   : wxFilterInputStream(stream)
 134 {
 135     Init(flags);
 136 }
 137
 138 wxZlibInputStream::wxZlibInputStream(wxInputStream *stream, int flags)
 139   : wxFilterInputStream(stream)
 140 {
 141     Init(flags);
 142 }
 143
 144 void wxZlibInputStream::Init(int flags)
 145 {
 146   m_inflate = NULL;
 147   m_z_buffer = new unsigned char[ZSTREAM_BUFFER_SIZE];
 148   m_z_size = ZSTREAM_BUFFER_SIZE;
 149   m_pos = 0;
 150
 151   // if gzip is asked for but not supported...
 152   if ((flags == wxZLIB_GZIP || flags == wxZLIB_AUTO) && !CanHandleGZip()) {
 153     if (flags == wxZLIB_AUTO) {
 154       // an error will come later if the input turns out not to be a zlib
 155       flags = wxZLIB_ZLIB;
 156     }
 157     else {
 158       wxLogError(_("Gzip not supported by this version of zlib"));
 159       m_lasterror = wxSTREAM_READ_ERROR;
 160       return;
 161     }
 162   }
 163
 164   if (m_z_buffer) {
 165     m_inflate = new z_stream_s;
 166
 167     if (m_inflate) {
 168       memset(m_inflate, 0, sizeof(z_stream_s));
 169
 170       // see zlib.h for documentation on windowBits
 171       int windowBits = MAX_WBITS;
 172       switch (flags) {
 173         case wxZLIB_NO_HEADER:  windowBits = -MAX_WBITS; break;
 174         case wxZLIB_ZLIB:       windowBits = MAX_WBITS; break;
 175         case wxZLIB_GZIP:       windowBits = MAX_WBITS | ZSTREAM_GZIP; break;
 176         case wxZLIB_AUTO:       windowBits = MAX_WBITS | ZSTREAM_AUTO; break;
 177         default:                wxFAIL_MSG(wxT("Invalid zlib flag"));
 178       }
 179
 180       if (inflateInit2(m_inflate, windowBits) == Z_OK)
 181         return;
 182     }
 183   }
 184
 185   wxLogError(_("Can't initialize zlib inflate stream."));
 186   m_lasterror = wxSTREAM_READ_ERROR;
 187 }
 188
 189 wxZlibInputStream::~wxZlibInputStream()
 190 {
 191   inflateEnd(m_inflate);
 192   delete m_inflate;
 193
 194   delete [] m_z_buffer;
 195 }
 196
 197 size_t wxZlibInputStream::OnSysRead(void *buffer, size_t size)
 198 {
 199   wxASSERT_MSG(m_inflate && m_z_buffer, wxT("Inflate stream not open"));
 200
 201   if (!m_inflate || !m_z_buffer)
 202     m_lasterror = wxSTREAM_READ_ERROR;
 203   if (!IsOk() || !size)
 204     return 0;
 205
 206   int err = Z_OK;
 207   m_inflate->next_out = (unsigned char *)buffer;
 208   m_inflate->avail_out = size;
 209
 210   while (err == Z_OK && m_inflate->avail_out > 0) {
 211     if (m_inflate->avail_in == 0 && m_parent_i_stream->IsOk()) {
 212       m_parent_i_stream->Read(m_z_buffer, m_z_size);
 213       m_inflate->next_in = m_z_buffer;
 214       m_inflate->avail_in = m_parent_i_stream->LastRead();
 215     }
 216     err = inflate(m_inflate, Z_SYNC_FLUSH);
 217   }
 218
 219   switch (err) {
 220     case Z_OK:
 221         break;
 222
 223     case Z_STREAM_END:
 224       if (m_inflate->avail_out) {
 225         // Unread any data taken from past the end of the deflate stream, so that
 226         // any additional data can be read from the underlying stream (the crc
 227         // in a gzip for example)
 228         if (m_inflate->avail_in) {
 229           m_parent_i_stream->Reset();
 230           m_parent_i_stream->Ungetch(m_inflate->next_in, m_inflate->avail_in);
 231           m_inflate->avail_in = 0;
 232         }
 233         m_lasterror = wxSTREAM_EOF;
 234       }
 235       break;
 236
 237     case Z_BUF_ERROR:
 238       // Indicates that zlib was expecting more data, but the parent stream
 239       // has none. Other than Eof the error will have been already reported
 240       // by the parent strean,
 241       m_lasterror = wxSTREAM_READ_ERROR;
 242       if (m_parent_i_stream->Eof())
 243       {
 244           wxLogError(_("Can't read inflate stream: unexpected EOF in underlying stream."));
 245       }
 246       break;
 247
 248     default:
 249       wxString msg(m_inflate->msg, *wxConvCurrent);
 250       if (!msg)
 251         msg = wxString::Format(_("zlib error %d"), err);
 252       wxLogError(_("Can't read from inflate stream: %s"), msg.c_str());
 253       m_lasterror = wxSTREAM_READ_ERROR;
 254   }
 255
 256   size -= m_inflate->avail_out;
 257   m_pos += size;
 258   return size;
 259 }
 260
 261 /* static */ bool wxZlibInputStream::CanHandleGZip()
 262 {
 263   const char *dot = strchr(zlibVersion(), '.');
 264   int major = atoi(zlibVersion());
 265   int minor = dot ? atoi(dot + 1) : 0;
 266   return major > 1 || (major == 1 && minor >= 2);
 267 }
 268
 269 bool wxZlibInputStream::SetDictionary(const char *data, const size_t datalen)
 270 {
 271     return (inflateSetDictionary(m_inflate, (Bytef*)data, datalen) == Z_OK);
 272 }
 273
 274 bool wxZlibInputStream::SetDictionary(const wxMemoryBuffer &buf)
 275 {
 276     return SetDictionary((char*)buf.GetData(), buf.GetDataLen());
 277 }
 278
 279
 280 //////////////////////
 281 // wxZlibOutputStream
 282 //////////////////////
 283
 284 wxZlibOutputStream::wxZlibOutputStream(wxOutputStream& stream,
 285                                        int level,
 286                                        int flags)
 287  : wxFilterOutputStream(stream)
 288 {
 289     Init(level, flags);
 290 }
 291
 292 wxZlibOutputStream::wxZlibOutputStream(wxOutputStream *stream,
 293                                        int level,
 294                                        int flags)
 295  : wxFilterOutputStream(stream)
 296 {
 297     Init(level, flags);
 298 }
 299
 300 void wxZlibOutputStream::Init(int level, int flags)
 301 {
 302   m_deflate = NULL;
 303   m_z_buffer = new unsigned char[ZSTREAM_BUFFER_SIZE];
 304   m_z_size = ZSTREAM_BUFFER_SIZE;
 305   m_pos = 0;
 306
 307   if ( level == -1 )
 308   {
 309     level = Z_DEFAULT_COMPRESSION;
 310   }
 311   else
 312   {
 313     wxASSERT_MSG(level >= 0 && level <= 9, wxT("wxZlibOutputStream compression level must be between 0 and 9!"));
 314   }
 315
 316   // if gzip is asked for but not supported...
 317   if (flags == wxZLIB_GZIP && !CanHandleGZip()) {
 318     wxLogError(_("Gzip not supported by this version of zlib"));
 319     m_lasterror = wxSTREAM_WRITE_ERROR;
 320     return;
 321   }
 322
 323   if (m_z_buffer) {
 324     m_deflate = new z_stream_s;
 325
 326     if (m_deflate) {
 327       memset(m_deflate, 0, sizeof(z_stream_s));
 328       m_deflate->next_out = m_z_buffer;
 329       m_deflate->avail_out = m_z_size;
 330
 331       // see zlib.h for documentation on windowBits
 332       int windowBits = MAX_WBITS;
 333       switch (flags) {
 334         case wxZLIB_NO_HEADER:  windowBits = -MAX_WBITS; break;
 335         case wxZLIB_ZLIB:       windowBits = MAX_WBITS; break;
 336         case wxZLIB_GZIP:       windowBits = MAX_WBITS | ZSTREAM_GZIP; break;
 337         default:                wxFAIL_MSG(wxT("Invalid zlib flag"));
 338       }
 339
 340       if (deflateInit2(m_deflate, level, Z_DEFLATED, windowBits,
 341                        8, Z_DEFAULT_STRATEGY) == Z_OK)
 342         return;
 343     }
 344   }
 345
 346   wxLogError(_("Can't initialize zlib deflate stream."));
 347   m_lasterror = wxSTREAM_WRITE_ERROR;
 348 }
 349
 350 bool wxZlibOutputStream::Close()
 351  {
 352   DoFlush(true);
 353    deflateEnd(m_deflate);
 354    wxDELETE(m_deflate);
 355    wxDELETEA(m_z_buffer);
 356
 357   return wxFilterOutputStream::Close() && IsOk();
 358  }
 359
 360 void wxZlibOutputStream::DoFlush(bool final)
 361 {
 362   if (!m_deflate || !m_z_buffer)
 363     m_lasterror = wxSTREAM_WRITE_ERROR;
 364   if (!IsOk())
 365     return;
 366
 367   int err = Z_OK;
 368   bool done = false;
 369
 370   while (err == Z_OK || err == Z_STREAM_END) {
 371     size_t len = m_z_size  - m_deflate->avail_out;
 372     if (len) {
 373       if (m_parent_o_stream->Write(m_z_buffer, len).LastWrite() != len) {
 374         m_lasterror = wxSTREAM_WRITE_ERROR;
 375         wxLogDebug(wxT("wxZlibOutputStream: Error writing to underlying stream"));
 376         break;
 377       }
 378       m_deflate->next_out = m_z_buffer;
 379       m_deflate->avail_out = m_z_size;
 380     }
 381
 382     if (done)
 383       break;
 384     err = deflate(m_deflate, final ? Z_FINISH : Z_FULL_FLUSH);
 385     done = m_deflate->avail_out != 0 || err == Z_STREAM_END;
 386   }
 387 }
 388
 389 size_t wxZlibOutputStream::OnSysWrite(const void *buffer, size_t size)
 390 {
 391   wxASSERT_MSG(m_deflate && m_z_buffer, wxT("Deflate stream not open"));
 392
 393   if (!m_deflate || !m_z_buffer)
 394   {
 395     // notice that this will make IsOk() test just below return false
 396     m_lasterror = wxSTREAM_WRITE_ERROR;
 397   }
 398
 399   if (!IsOk() || !size)
 400     return 0;
 401
 402   int err = Z_OK;
 403   m_deflate->next_in = (unsigned char *)buffer;
 404   m_deflate->avail_in = size;
 405
 406   while (err == Z_OK && m_deflate->avail_in > 0) {
 407     if (m_deflate->avail_out == 0) {
 408       m_parent_o_stream->Write(m_z_buffer, m_z_size);
 409       if (m_parent_o_stream->LastWrite() != m_z_size) {
 410         m_lasterror = wxSTREAM_WRITE_ERROR;
 411         wxLogDebug(wxT("wxZlibOutputStream: Error writing to underlying stream"));
 412         break;
 413       }
 414
 415       m_deflate->next_out = m_z_buffer;
 416       m_deflate->avail_out = m_z_size;
 417     }
 418
 419     err = deflate(m_deflate, Z_NO_FLUSH);
 420   }
 421
 422   if (err != Z_OK) {
 423     m_lasterror = wxSTREAM_WRITE_ERROR;
 424     wxString msg(m_deflate->msg, *wxConvCurrent);
 425     if (!msg)
 426       msg = wxString::Format(_("zlib error %d"), err);
 427     wxLogError(_("Can't write to deflate stream: %s"), msg.c_str());
 428   }
 429
 430   size -= m_deflate->avail_in;
 431   m_pos += size;
 432   return size;
 433 }
 434
 435 /* static */ bool wxZlibOutputStream::CanHandleGZip()
 436 {
 437   return wxZlibInputStream::CanHandleGZip();
 438 }
 439
 440 bool wxZlibOutputStream::SetDictionary(const char *data, const size_t datalen)
 441 {
 442     return (deflateSetDictionary(m_deflate, (Bytef*)data, datalen) == Z_OK);
 443 }
 444
 445 bool wxZlibOutputStream::SetDictionary(const wxMemoryBuffer &buf)
 446 {
 447     return SetDictionary((char*)buf.GetData(), buf.GetDataLen());
 448 }
 449
 450 #endif
 451   // wxUSE_ZLIB && wxUSE_STREAMS