fixing overrelease and out-of-bounds write, fixes #13725

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

diff --git a/src/common/mstream.cpp b/src/common/mstream.cpp
index b81a7f44a0cd030adb1ea6446f6f6035745f1449..66af403e2f8140fe46874da4ddd3dcf8902f4cd1 100644 (file)
--- a/src/common/mstream.cpp
+++ b/src/common/mstream.cpp
@@ -21,15 +21,19 @@
 #include "wx/wxprec.h"
 
 #ifdef __BORLANDC__
-  #pragma hdrstop
+    #pragma hdrstop
 #endif
 
 #if wxUSE_STREAMS
 
-#include <stdlib.h>
-#include "wx/stream.h"
 #include "wx/mstream.h"
 
+#ifndef   WX_PRECOMP
+    #include  "wx/stream.h"
+#endif  //WX_PRECOMP
+
+#include <stdlib.h>
+
 // ============================================================================
 // implementation
 // ============================================================================
@@ -38,10 +42,12 @@
 // wxMemoryInputStream
 // ----------------------------------------------------------------------------
 
+IMPLEMENT_ABSTRACT_CLASS(wxMemoryInputStream, wxInputStream)
+
 wxMemoryInputStream::wxMemoryInputStream(const void *data, size_t len)
 {
     m_i_streambuf = new wxStreamBuffer(wxStreamBuffer::read);
-    m_i_streambuf->SetBufferIO((void *)data, len); // const_cast
+    m_i_streambuf->SetBufferIO(const_cast<void *>(data), len);
     m_i_streambuf->SetIntPosition(0); // seek to start pos
     m_i_streambuf->Fixed(true);
 
@@ -50,12 +56,17 @@ wxMemoryInputStream::wxMemoryInputStream(const void *data, size_t len)
 
 wxMemoryInputStream::wxMemoryInputStream(const wxMemoryOutputStream& stream)
 {
-    ssize_t len = (ssize_t)stream.GetLength();
-    if (len == wxInvalidOffset) {
+    const wxFileOffset lenFile = stream.GetLength();
+    if ( lenFile == wxInvalidOffset )
+    {
         m_i_streambuf = NULL;
         m_lasterror = wxSTREAM_EOF;
         return;
     }
+
+    const size_t len = wx_truncate_cast(size_t, lenFile);
+    wxASSERT_MSG( len == lenFile + size_t(0), wxT("huge files not supported") );
+
     m_i_streambuf = new wxStreamBuffer(wxStreamBuffer::read);
     m_i_streambuf->SetBufferIO(len); // create buffer
     stream.CopyTo(m_i_streambuf->GetBufferStart(), len);
@@ -64,6 +75,35 @@ wxMemoryInputStream::wxMemoryInputStream(const wxMemoryOutputStream& stream)
     m_length = len;
 }
 
+void
+wxMemoryInputStream::InitFromStream(wxInputStream& stream, wxFileOffset lenFile)
+{
+    if ( lenFile == wxInvalidOffset )
+        lenFile = stream.GetLength();
+
+    if ( lenFile == wxInvalidOffset )
+    {
+        m_i_streambuf = NULL;
+        m_lasterror = wxSTREAM_EOF;
+        return;
+    }
+
+    const size_t len = wx_truncate_cast(size_t, lenFile);
+    wxASSERT_MSG( (wxFileOffset)len == lenFile, wxT("huge files not supported") );
+
+    m_i_streambuf = new wxStreamBuffer(wxStreamBuffer::read);
+    m_i_streambuf->SetBufferIO(len); // create buffer
+    stream.Read(m_i_streambuf->GetBufferStart(), len);
+    m_i_streambuf->SetIntPosition(0); // seek to start pos
+    m_i_streambuf->Fixed(true);
+    m_length = stream.LastRead();
+}
+
+bool wxMemoryInputStream::CanRead() const
+{
+    return m_i_streambuf->GetIntPosition() != m_length;
+}
+
 wxMemoryInputStream::~wxMemoryInputStream()
 {
     delete m_i_streambuf;
@@ -83,11 +123,6 @@ char wxMemoryInputStream::Peek()
     return buf[pos];
 }
 
-bool wxMemoryInputStream::Eof() const
-{
-    return !m_i_streambuf->GetBytesLeft();
-}
-
 size_t wxMemoryInputStream::OnSysRead(void *buffer, size_t nbytes)
 {
     size_t pos = m_i_streambuf->GetIntPosition();
@@ -118,6 +153,8 @@ wxFileOffset wxMemoryInputStream::OnSysTell() const
 // wxMemoryOutputStream
 // ----------------------------------------------------------------------------
 
+IMPLEMENT_DYNAMIC_CLASS(wxMemoryOutputStream, wxOutputStream)
+
 wxMemoryOutputStream::wxMemoryOutputStream(void *data, size_t len)
 {
     m_o_streambuf = new wxStreamBuffer(wxStreamBuffer::write);
@@ -157,7 +194,7 @@ wxFileOffset wxMemoryOutputStream::OnSysTell() const
 
 size_t wxMemoryOutputStream::CopyTo(void *buffer, size_t len) const
 {
-    wxCHECK_MSG( buffer, 0, _T("must have buffer to CopyTo") );
+    wxCHECK_MSG( buffer, 0, wxT("must have buffer to CopyTo") );
 
     if ( len > GetSize() )
         len = GetSize();