X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/b2c31089c2bd10eb5a33f4d43654e85b7ca451f0..b483f5fed274a9152faab05b0ebb4e5f5158c506:/src/common/string.cpp?ds=sidebyside

diff --git a/src/common/string.cpp b/src/common/string.cpp
index 7d77c76f8f..78008c79a7 100644
--- a/src/common/string.cpp
+++ b/src/common/string.cpp
@@ -1077,16 +1077,21 @@ wxChar *wxString::GetWriteBuf(size_t nLen)
 // put string back in a reasonable state after GetWriteBuf
 void wxString::UngetWriteBuf()
 {
-  GetStringData()->nDataLength = wxStrlen(m_pchData);
-  GetStringData()->Validate(true);
+  UngetWriteBuf(wxStrlen(m_pchData));
 }
 
 void wxString::UngetWriteBuf(size_t nLen)
 {
-  GetStringData()->nDataLength = nLen;
-  GetStringData()->Validate(true);
+  wxStringData * const pData = GetStringData();
+
+  wxASSERT_MSG( nLen < pData->nAllocLength, _T("buffer overrun") );
+
+  // the strings we store are always NUL-terminated
+  pData->data()[nLen] = _T('\0');
+  pData->nDataLength = nLen;
+  pData->Validate(true);
 }
-#endif
+#endif // !wxUSE_STL
 
 // ---------------------------------------------------------------------------
 // data access
@@ -1832,15 +1837,29 @@ int wxString::PrintfV(const wxChar* pszFormat, va_list argptr)
         // buffer were large enough (newer standards such as Unix98)
         if ( len < 0 )
         {
+#if wxUSE_WXVSNPRINTF
+            // we know that our own implementation of wxVsnprintf() returns -1
+            // only for a format error - thus there's something wrong with
+            // the user's format string
+            return -1;
+#else // assume that system version only returns error if not enough space
             // still not enough, as we don't know how much we need, double the
             // current size of the buffer
             size *= 2;
+#endif // wxUSE_WXVSNPRINTF/!wxUSE_WXVSNPRINTF
         }
         else if ( len >= size )
         {
+#if wxUSE_WXVSNPRINTF
+            // we know that our own implementation of wxVsnprintf() returns 
+            // size+1 when there's not enough space but that's not the size
+            // of the required buffer!
+            size *= 2;      // so we just double the current size of the buffer
+#else
             // some vsnprintf() implementations NUL-terminate the buffer and
             // some don't in len == size case, to be safe always add 1
             size = len + 1;
+#endif
         }
         else // ok, there was enough space
         {