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 #if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
  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(wxConvFile));
  44     if (m_Archive == NULL)
  45     {
  46         m_lasterror = wxSTREAM_READ_ERROR;
  47         return;
  48     }
  49     // TODO what encoding does ZIP use?
  50     if (unzLocateFile((unzFile)m_Archive, file.ToAscii(), 0) != UNZ_OK)
  51     {
  52         m_lasterror = wxSTREAM_READ_ERROR;
  53         return;
  54     }
  55
  56     unzGetCurrentFileInfo((unzFile)m_Archive, &zinfo, (char*) NULL, 0, (void*) NULL, 0, (char*) NULL, 0);
  57
  58     if (unzOpenCurrentFile((unzFile)m_Archive) != UNZ_OK)
  59     {
  60         m_lasterror = wxSTREAM_READ_ERROR;
  61         return;
  62     }
  63     m_Size = (size_t)zinfo.uncompressed_size;
  64 }
  65
  66
  67
  68 wxZipInputStream::~wxZipInputStream()
  69 {
  70     if (m_Archive)
  71     {
  72         if (m_Size != 0)
  73             unzCloseCurrentFile((unzFile)m_Archive);
  74         unzClose((unzFile)m_Archive);
  75     }
  76 }
  77
  78 bool wxZipInputStream::Eof() const
  79 {
  80     wxASSERT_MSG( m_Pos <= (off_t)m_Size,
  81                   _T("wxZipInputStream: invalid current position") );
  82
  83     return m_Pos >= (off_t)m_Size;
  84 }
  85
  86
  87 size_t wxZipInputStream::OnSysRead(void *buffer, size_t bufsize)
  88 {
  89     wxASSERT_MSG( m_Pos <= (off_t)m_Size,
  90                   _T("wxZipInputStream: invalid current position") );
  91
  92     if ( m_Pos >= (off_t)m_Size )
  93     {
  94         m_lasterror = wxSTREAM_EOF;
  95         return 0;
  96     }
  97
  98     if (m_Pos + bufsize > m_Size)
  99         bufsize = m_Size - m_Pos;
 100
 101     unzReadCurrentFile((unzFile)m_Archive, buffer, bufsize);
 102     m_Pos += bufsize;
 103
 104     return bufsize;
 105 }
 106
 107
 108
 109 off_t wxZipInputStream::OnSysSeek(off_t seek, wxSeekMode mode)
 110 {
 111     // NB: since ZIP files don't natively support seeking, we have to
 112     //     implement a brute force workaround -- reading all the data
 113     //     between current and the new position (or between beginning of
 114     //     the file and new position...)
 115
 116     off_t nextpos;
 117
 118     switch ( mode )
 119     {
 120         case wxFromCurrent : nextpos = seek + m_Pos; break;
 121         case wxFromStart : nextpos = seek; break;
 122         case wxFromEnd : nextpos = m_Size - 1 + seek; break;
 123         default : nextpos = m_Pos; break; /* just to fool compiler, never happens */
 124     }
 125
 126     size_t toskip;
 127     if ( nextpos > m_Pos )
 128     {
 129         toskip = nextpos - m_Pos;
 130     }
 131     else
 132     {
 133         unzCloseCurrentFile((unzFile)m_Archive);
 134         if (unzOpenCurrentFile((unzFile)m_Archive) != UNZ_OK)
 135         {
 136             m_lasterror = wxSTREAM_READ_ERROR;
 137             return m_Pos;
 138         }
 139         toskip = nextpos;
 140     }
 141
 142     if ( toskip > 0 )
 143     {
 144         const size_t BUFSIZE = 4096;
 145         size_t sz;
 146         char buffer[BUFSIZE];
 147         while ( toskip > 0 )
 148         {
 149             sz = wxMin(toskip, BUFSIZE);
 150             unzReadCurrentFile((unzFile)m_Archive, buffer, sz);
 151             toskip -= sz;
 152         }
 153     }
 154
 155     m_Pos = nextpos;
 156     return m_Pos;
 157 }
 158
 159 #endif
 160   // wxUSE_STREAMS && wxUSE_ZIPSTREAM && wxUSE_ZLIB