Added comments

[wxWidgets.git] / src / common / stream.cpp

diff --git a/src/common/stream.cpp b/src/common/stream.cpp
index 76a0b3fdbf15bc4930f34fdc694386a90335f5a1..162dcf19cb10e824c02412a205302f2b96e2cafe 100644 (file)
--- a/src/common/stream.cpp
+++ b/src/common/stream.cpp
@@ -195,6 +195,23 @@ void wxStreamBuffer::PutChar(char c)
   m_stream->m_lastcount = 1;
 }
 
+char wxStreamBuffer::Peek()
+{
+  char c;
+
+  wxASSERT(m_stream != NULL && m_buffer_size != 0);
+
+  if (!GetDataLeft()) {
+    CHECK_ERROR(wxStream_READ_ERR);
+    return 0;
+  }
+
+  GetFromBuffer(&c, 1);
+  m_buffer_pos--;
+
+  return c;
+}
+
 char wxStreamBuffer::GetChar()
 {
   char c;
@@ -248,7 +265,7 @@ size_t wxStreamBuffer::Read(void *buffer, size_t size)
       buffer = (char *)buffer + buf_left; // ANSI C++ violation.
 
       if (!FillBuffer()) {
-        CHECK_ERROR(wxStream_READ_ERR);
+        CHECK_ERROR(wxStream_EOF);
         return (m_stream->m_lastcount = orig_size-size);
       }
     } else {
@@ -576,6 +593,10 @@ wxInputStream& wxInputStream::Read(wxOutputStream& stream_out)
 
 off_t wxInputStream::SeekI(off_t pos, wxSeekMode mode)
 {
+  //should be check and improve, just to remove a slight bug !
+  // I don't know whether it should be put as well in wxFileInputStream::OnSysSeek ?
+  if (m_lasterror==wxSTREAM_EOF) m_lasterror=wxSTREAM_NOERROR;
+
   return OnSysSeek(pos, mode);
 }
 
@@ -645,9 +666,56 @@ wxOutputStream& wxOutputStream::operator<<(wxObject& obj)
 }
 #endif
 
+// ----------------------------------------------------------------------------
+// wxCountingOutputStream
+// ----------------------------------------------------------------------------
+
+wxCountingOutputStream::wxCountingOutputStream ()
+  : wxOutputStream()
+{
+   m_currentPos = 0;
+}
+
+size_t wxCountingOutputStream::GetSize() const
+{
+  return m_lastcount;
+}
+
+size_t wxCountingOutputStream::OnSysWrite(const void *WXUNUSED(buffer), size_t size)
+{
+  m_currentPos += size;
+  if (m_currentPos > m_lastcount) m_lastcount = m_currentPos;
+  return m_currentPos;
+}
+
+off_t wxCountingOutputStream::OnSysSeek(off_t pos, wxSeekMode mode)
+{
+  if (mode == wxFromStart)
+  {
+    m_currentPos = pos;
+  }
+  if (mode == wxFromEnd)
+  {
+    m_currentPos = m_lastcount + pos;
+  }
+  else
+  {
+    m_currentPos += pos;
+  }
+  if (m_currentPos > m_lastcount) m_lastcount = m_currentPos;
+  
+  return m_currentPos;  // ?
+}
+
+off_t wxCountingOutputStream::OnSysTell() const
+{
+  return m_currentPos;  // ?
+}
+  
 // ----------------------------------------------------------------------------
 // wxFilterInputStream
 // ----------------------------------------------------------------------------
+
 wxFilterInputStream::wxFilterInputStream()
   : wxInputStream()
 {
@@ -696,6 +764,11 @@ wxBufferedInputStream::~wxBufferedInputStream()
   delete m_i_streambuf;
 }
 
+char wxBufferedInputStream::Peek()
+{
+  return m_i_streambuf->Peek();
+}
+
 wxInputStream& wxBufferedInputStream::Read(void *buffer, size_t size)
 {
   size_t retsize;