src/common/zipstream.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 "zipstream.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/zipstream.h"
  27 #include "unzip.h"
  28
  29 wxZipInputStream::wxZipInputStream(const wxString& archive, const wxString& file) : wxInputStream()
  30 {
  31     unz_file_info zinfo;
  32
  33     m_Pos = 0;
  34     m_Size = 0;
  35     m_Archive = (void*) unzOpen(archive);
  36     if (m_Archive == NULL)
  37     {
  38         m_lasterror = wxStream_READ_ERR;
  39         return;
  40     }
  41     if (unzLocateFile((unzFile)m_Archive, file, 0) != UNZ_OK)
  42     {
  43         m_lasterror = wxStream_READ_ERR;
  44         return;
  45     }
  46
  47     unzGetCurrentFileInfo((unzFile)m_Archive, &zinfo, (char*) NULL, 0, (void*) NULL, 0, (char*) NULL, 0);
  48
  49     if (unzOpenCurrentFile((unzFile)m_Archive) != UNZ_OK)
  50     {
  51         m_lasterror = wxStream_READ_ERR;
  52         return;
  53     }
  54     m_Size = zinfo.uncompressed_size;
  55 }
  56
  57
  58
  59 wxZipInputStream::~wxZipInputStream()
  60 {
  61     if (m_Archive)
  62     {
  63         if (m_Size != 0)
  64             unzCloseCurrentFile((unzFile)m_Archive);
  65         unzClose((unzFile)m_Archive);
  66     }
  67 }
  68
  69
  70
  71 size_t wxZipInputStream::OnSysRead(void *buffer, size_t bufsize)
  72 {
  73     if (m_Pos + bufsize > m_Size) bufsize = m_Size - m_Pos;
  74     unzReadCurrentFile((unzFile)m_Archive, buffer, bufsize);
  75     m_Pos += bufsize;
  76     return bufsize;
  77 }
  78
  79
  80
  81 off_t wxZipInputStream::OnSysSeek(off_t seek, wxSeekMode mode)
  82 {
  83     off_t nextpos;
  84     void *buf;
  85
  86     switch (mode)
  87     {
  88         case wxFromCurrent : nextpos = seek + m_Pos; break;
  89         case wxFromStart : nextpos = seek; break;
  90         case wxFromEnd : nextpos = m_Size - 1 + seek; break;
  91         default : nextpos = m_Pos; break; /* just to fool compiler, never happens */
  92     }
  93
  94     // cheated seeking :
  95     if (nextpos > m_Pos)
  96     {
  97         buf = malloc(nextpos - m_Pos);
  98         unzReadCurrentFile((unzFile)m_Archive, buf, nextpos -  m_Pos);
  99         free(buf);
 100     }
 101     else if (nextpos < m_Pos) {
 102         unzCloseCurrentFile((unzFile)m_Archive);
 103         if (unzOpenCurrentFile((unzFile)m_Archive) != UNZ_OK)
 104         {
 105             m_lasterror = wxStream_READ_ERR;
 106             return m_Pos;
 107         }
 108         buf = malloc(nextpos);
 109         unzReadCurrentFile((unzFile)m_Archive, buf, nextpos);
 110         free(buf);
 111     }
 112
 113     m_Pos = nextpos;
 114     return m_Pos;
 115 }
 116
 117 #endif
 118   // wxUSE_STREAMS && wxUSE_ZIPSTREAM && wxUSE_ZLIB