src/common/mstream.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        mstream.cpp
   3 // Purpose:     "Memory stream" classes
   4 // Author:      Guilhem Lavaux
   5 // Modified by:
   6 // Created:     04/01/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Guilhem Lavaux
   9 // Licence:     wxWindows license
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 #ifdef __GNUG__
  13 #pragma implementation "mstream.h"
  14 #endif
  15
  16 // For compilers that support precompilation, includes "wx.h".
  17 #include "wx/wxprec.h"
  18
  19 #ifdef __BORLANDC__
  20   #pragma hdrstop
  21 #endif
  22
  23 #if wxUSE_STREAMS
  24
  25 #include <stdlib.h>
  26 #include "wx/stream.h"
  27 #include "wx/mstream.h"
  28
  29 // ----------------------------------------------------------------------------
  30 // wxMemoryInputStream
  31 // ----------------------------------------------------------------------------
  32
  33 wxMemoryInputStream::wxMemoryInputStream(const char *data, size_t len)
  34   : wxInputStream()
  35 {
  36   m_i_streambuf = new wxStreamBuffer(wxStreamBuffer::read);
  37   m_i_streambuf->SetBufferIO((char*) data, (char*) (data+len));
  38   m_i_streambuf->SetIntPosition(0); // seek to start pos
  39   m_i_streambuf->Fixed(TRUE);
  40
  41   m_length = len;
  42 }
  43
  44 wxMemoryInputStream::~wxMemoryInputStream()
  45 {
  46   delete m_i_streambuf;
  47 }
  48
  49 char wxMemoryInputStream::Peek()
  50 {
  51   return m_i_streambuf->GetBufferStart()[m_i_streambuf->GetIntPosition()];
  52 }
  53
  54 size_t wxMemoryInputStream::OnSysRead(void *buffer, size_t nbytes)
  55 {
  56   size_t bufsize = m_i_streambuf->GetBufferEnd() - m_i_streambuf->GetBufferStart();
  57   size_t oldpos = m_i_streambuf->GetIntPosition();
  58   m_i_streambuf->Read(buffer, nbytes);
  59   size_t newpos = m_i_streambuf->GetIntPosition();
  60   if (newpos == 0) return bufsize - oldpos;
  61   else return newpos - oldpos;
  62 }
  63
  64 off_t wxMemoryInputStream::OnSysSeek(off_t pos, wxSeekMode mode)
  65 {
  66   return m_i_streambuf->Seek(pos, mode);
  67 }
  68
  69 off_t wxMemoryInputStream::OnSysTell() const
  70 {
  71   return m_i_streambuf->Tell();
  72 }
  73
  74 // ----------------------------------------------------------------------------
  75 // wxMemoryOutputStream
  76 // ----------------------------------------------------------------------------
  77
  78 wxMemoryOutputStream::wxMemoryOutputStream(char *data, size_t len)
  79   : wxOutputStream()
  80 {
  81   m_o_streambuf = new wxStreamBuffer(wxStreamBuffer::write);
  82   if (data)
  83     m_o_streambuf->SetBufferIO(data, data+len);
  84   m_o_streambuf->Fixed(FALSE);
  85   m_o_streambuf->Flushable(FALSE);
  86 }
  87
  88 wxMemoryOutputStream::~wxMemoryOutputStream()
  89 {
  90   delete m_o_streambuf;
  91 }
  92
  93 size_t wxMemoryOutputStream::OnSysWrite(const void *buffer, size_t nbytes)
  94 {
  95   size_t bufsize = m_o_streambuf->GetBufferEnd() - m_o_streambuf->GetBufferStart();
  96   size_t oldpos = m_o_streambuf->GetIntPosition();
  97   m_o_streambuf->Write(buffer, nbytes);
  98   size_t newpos = m_o_streambuf->GetIntPosition();
  99   if (newpos == 0) return bufsize - oldpos;
 100   else return newpos - oldpos;
 101 }
 102
 103 off_t wxMemoryOutputStream::OnSysSeek(off_t pos, wxSeekMode mode)
 104 {
 105   return m_o_streambuf->Seek(pos, mode);
 106 }
 107
 108 off_t wxMemoryOutputStream::OnSysTell() const
 109 {
 110   return m_o_streambuf->Tell();
 111 }
 112
 113 size_t wxMemoryOutputStream::CopyTo(char *buffer, size_t len) const
 114 {
 115   if (!buffer)
 116     return 0;
 117
 118   if (len > GetSize())
 119     len = GetSize();
 120
 121   memcpy(buffer, m_o_streambuf->GetBufferStart(), len);
 122   return len;
 123 }
 124
 125 #endif