X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/29a96d3c098cefe7cb388ee914b8e496d7970406..08670ea85abf4b4946a9ce64971b591d7b1ee30b:/src/common/textfile.cpp

diff --git a/src/common/textfile.cpp b/src/common/textfile.cpp
index db0d4b41ba..91a86d5fb4 100644
--- a/src/common/textfile.cpp
+++ b/src/common/textfile.cpp
@@ -64,7 +64,7 @@ bool wxTextFile::OnOpen(const wxString &strBufferName, wxTextBufferOpenMode Open
     switch ( OpenMode )
     {
         default:
-            wxFAIL_MSG( _T("unknown open mode in wxTextFile::Open") );
+            wxFAIL_MSG( wxT("unknown open mode in wxTextFile::Open") );
             // fall through
 
         case ReadAccess :
@@ -89,7 +89,7 @@ bool wxTextFile::OnClose()
 bool wxTextFile::OnRead(const wxMBConv& conv)
 {
     // file should be opened
-    wxASSERT_MSG( m_file.IsOpened(), _T("can't read closed file") );
+    wxASSERT_MSG( m_file.IsOpened(), wxT("can't read closed file") );
 
     // read the entire file in memory: this is not the most efficient thing to
     // do it but there is no good way to avoid it in Unicode build because if
@@ -124,12 +124,19 @@ bool wxTextFile::OnRead(const wxMBConv& conv)
             return false;
 
         // if the file is seekable, also check that we're at its beginning
-        wxASSERT_MSG( m_file.Tell() == 0, _T("should be at start of file") );
+        wxASSERT_MSG( m_file.Tell() == 0, wxT("should be at start of file") );
 
         char *dst = buf.data();
-        for ( ;; )
+        for ( size_t nRemaining = bufSize; nRemaining > 0; )
         {
-            ssize_t nRead = m_file.Read(dst, BLOCK_SIZE);
+            size_t nToRead = BLOCK_SIZE;
+
+            // the file size could have changed, avoid overflowing the buffer
+            // even if it did
+            if ( nToRead > nRemaining )
+                nToRead = nRemaining;
+
+            ssize_t nRead = m_file.Read(dst, nToRead);
 
             if ( nRead == wxInvalidOffset )
             {
@@ -140,14 +147,16 @@ bool wxTextFile::OnRead(const wxMBConv& conv)
             if ( nRead == 0 )
             {
                 // this file can't be empty because we checked for this above
+                // so this must be the end of file
                 break;
             }
 
             dst += nRead;
+            nRemaining -= nRead;
         }
 
         wxASSERT_MSG( dst - buf.data() == (wxFileOffset)bufSize,
-                      _T("logic error") );
+                      wxT("logic error") );
     }
     else // file is not seekable
     {