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
  11 #endif
  12
  13 #include <wx/wxprec.h>
  14
  15 #ifdef __BORDLANDC__
  16 #pragma hdrstop
  17 #endif
  18
  19 #ifndef WXPRECOMP
  20 #include <wx/wx.h>
  21 #endif
  22
  23 #if wxUSE_ZLIB && wxUSE_STREAMS && wxUSE_ZIPSTREAM
  24
  25 #include <wx/stream.h>
  26 #include <wx/wfstream.h>
  27 #include <wx/zipstream.h>
  28 #include "unzip.h"
  29
  30
  31
  32
  33 wxZipInputStream::wxZipInputStream(const wxString& archive, const wxString& file) : wxInputStream()
  34 {
  35     unz_file_info zinfo;
  36
  37     m_Pos = 0;
  38     m_Size = 0;
  39     m_Archive = (void*) unzOpen(archive);
  40     if (m_Archive == NULL) {
  41         m_lasterror = wxStream_READ_ERR;
  42         return;
  43     }
  44     if (unzLocateFile((unzFile)m_Archive, file, 0) != UNZ_OK) {
  45         m_lasterror = wxStream_READ_ERR;
  46         return;
  47     }
  48     unzGetCurrentFileInfo((unzFile)m_Archive, &zinfo, NULL, 0, NULL, 0, NULL, 0);
  49
  50     if (unzOpenCurrentFile((unzFile)m_Archive) != UNZ_OK) {
  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         if (m_Size != 0)
  63             unzCloseCurrentFile((unzFile)m_Archive);
  64         unzClose((unzFile)m_Archive);
  65     }
  66 }
  67
  68
  69
  70 size_t wxZipInputStream::OnSysRead(void *buffer, size_t bufsize)
  71 {
  72     if (m_Pos + bufsize > m_Size) bufsize = m_Size - m_Pos;
  73     unzReadCurrentFile((unzFile)m_Archive, buffer, bufsize);
  74     m_Pos += bufsize;
  75     return bufsize;
  76 }
  77
  78
  79
  80 off_t wxZipInputStream::OnSysSeek(off_t seek, wxSeekMode mode)
  81 {
  82     off_t nextpos;
  83     void *buf;
  84
  85     switch (mode) {
  86         case wxFromCurrent : nextpos = seek + m_Pos; break;
  87         case wxFromStart : nextpos = seek; break;
  88         case wxFromEnd : nextpos = m_Size - 1 + seek; break;
  89         default : nextpos = m_Pos; break; /* just to fool compiler, never happens */
  90     }
  91
  92     // cheated seeking :
  93     if (nextpos > m_Pos) {
  94         buf = malloc(nextpos - m_Pos);
  95         unzReadCurrentFile((unzFile)m_Archive, buf, nextpos -  m_Pos);
  96         free(buf);
  97     }
  98     else if (nextpos < m_Pos) {
  99         unzCloseCurrentFile((unzFile)m_Archive);
 100         if (unzOpenCurrentFile((unzFile)m_Archive) != UNZ_OK) {
 101             m_lasterror = wxStream_READ_ERR;
 102             return m_Pos;
 103         }
 104         buf = malloc(nextpos);
 105         unzReadCurrentFile((unzFile)m_Archive, buf, nextpos);
 106         free(buf);
 107     }
 108
 109     m_Pos = nextpos;
 110     return m_Pos;
 111 }
 112
 113 #endif