src/common/zipstrm.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        zipstream.cpp
   3 // Purpose:     input stream for ZIP archive access
   4 // Author:      Vaclav Slavik
   5 // Copyright:   (c) 1999 Vaclav Slavik
   6 // Licence:     wxWindows Licence
   7 /////////////////////////////////////////////////////////////////////////////
   8
   9 #ifdef __GNUG__
  10 #pragma implementation "zipstrm.h"
  11 #endif
  12
  13 // For compilers that support precompilation, includes "wx.h".
  14 #include "wx/wxprec.h"
  15
  16 #ifdef __BORLANDC__
  17   #pragma hdrstop
  18 #endif
  19
  20 #if wxUSE_STREAMS && wxUSE_ZIPSTREAM && wxUSE_ZLIB
  21
  22 #include "wx/log.h"
  23 #include "wx/intl.h"
  24 #include "wx/stream.h"
  25 #include "wx/wfstream.h"
  26 #include "wx/zipstrm.h"
  27 #include "wx/utils.h"
  28
  29 /* Not the right solution (paths in makefiles) but... */
  30 #ifdef __BORLANDC__
  31 #include "../common/unzip.h"
  32 #else
  33 #include "unzip.h"
  34 #endif
  35
  36
  37 wxZipInputStream::wxZipInputStream(const wxString& archive, const wxString& file) : wxInputStream()
  38 {
  39     unz_file_info zinfo;
  40
  41     m_Pos = 0;
  42     m_Size = 0;
  43     m_Archive = (void*) unzOpen(archive.mb_str());
  44     if (m_Archive == NULL)
  45     {
  46         m_lasterror = wxSTREAM_READ_ERROR;
  47         return;
  48     }
  49     if (unzLocateFile((unzFile)m_Archive, file.mb_str(), 0) != UNZ_OK)
  50     {
  51         m_lasterror = wxSTREAM_READ_ERROR;
  52         return;
  53     }
  54
  55     unzGetCurrentFileInfo((unzFile)m_Archive, &zinfo, (char*) NULL, 0, (void*) NULL, 0, (char*) NULL, 0);
  56
  57     if (unzOpenCurrentFile((unzFile)m_Archive) != UNZ_OK)
  58     {
  59         m_lasterror = wxSTREAM_READ_ERROR;
  60         return;
  61     }
  62     m_Size = (size_t)zinfo.uncompressed_size;
  63 }
  64
  65
  66
  67 wxZipInputStream::~wxZipInputStream()
  68 {
  69     if (m_Archive)
  70     {
  71         if (m_Size != 0)
  72             unzCloseCurrentFile((unzFile)m_Archive);
  73         unzClose((unzFile)m_Archive);
  74     }
  75 }
  76
  77 bool wxZipInputStream::Eof() const
  78 {
  79     wxASSERT_MSG( m_Pos <= (off_t)m_Size,
  80                   _T("wxZipInputStream: invalid current position") );
  81
  82     return m_Pos >= (off_t)m_Size;
  83 }
  84
  85
  86 size_t wxZipInputStream::OnSysRead(void *buffer, size_t bufsize)
  87 {
  88     wxASSERT_MSG( m_Pos <= (off_t)m_Size,
  89                   _T("wxZipInputStream: invalid current position") );
  90
  91     if ( m_Pos >= (off_t)m_Size )
  92     {
  93         m_lasterror = wxSTREAM_EOF;
  94         return 0;
  95     }
  96
  97     if (m_Pos + bufsize > m_Size)
  98         bufsize = m_Size - m_Pos;
  99
 100     unzReadCurrentFile((unzFile)m_Archive, buffer, bufsize);
 101     m_Pos += bufsize;
 102
 103     return bufsize;
 104 }
 105
 106
 107
 108 off_t wxZipInputStream::OnSysSeek(off_t seek, wxSeekMode mode)
 109 {
 110     // NB: since ZIP files don't natively support seeking, we have to
 111     //     implement a brute force workaround -- reading all the data
 112     //     between current and the new position (or between beginning of
 113     //     the file and new position...)
 114
 115     off_t nextpos;
 116
 117     switch ( mode )
 118     {
 119         case wxFromCurrent : nextpos = seek + m_Pos; break;
 120         case wxFromStart : nextpos = seek; break;
 121         case wxFromEnd : nextpos = m_Size - 1 + seek; break;
 122         default : nextpos = m_Pos; break; /* just to fool compiler, never happens */
 123     }
 124
 125     size_t toskip = 0;
 126     if ( nextpos > m_Pos )
 127     {
 128         toskip = nextpos - m_Pos;
 129     }
 130     else
 131     {
 132         unzCloseCurrentFile((unzFile)m_Archive);
 133         if (unzOpenCurrentFile((unzFile)m_Archive) != UNZ_OK)
 134         {
 135             m_lasterror = wxSTREAM_READ_ERROR;
 136             return m_Pos;
 137         }
 138         toskip = nextpos;
 139     }
 140
 141     if ( toskip > 0 )
 142     {
 143         const size_t BUFSIZE = 4096;
 144         size_t sz;
 145         char buffer[BUFSIZE];
 146         while ( toskip > 0 )
 147         {
 148             sz = wxMin(toskip, BUFSIZE);
 149             unzReadCurrentFile((unzFile)m_Archive, buffer, sz);
 150             toskip -= sz;
 151         }
 152     }
 153
 154     m_Pos = nextpos;
 155     return m_Pos;
 156 }
 157
 158 #endif
 159   // wxUSE_STREAMS && wxUSE_ZIPSTREAM && wxUSE_ZLIB