DiffTextBuffer.cpp: Impletement 'TODO: speed this up via table lookup'

diff --git a/Src/DiffTextBuffer.cpp b/Src/DiffTextBuffer.cpp
index 21fab1c..44150c7 100644 (file)
--- a/Src/DiffTextBuffer.cpp
+++ b/Src/DiffTextBuffer.cpp
@@ -84,9 +84,8 @@ static void EscapeControlChars(String &s)
                // Is it a control character in the range 0..31 except TAB?
                if (!(c & ~_T('\x1F')) && c != _T('\t'))
                {
-                       // TODO: speed this up via table lookup
-                       // Bitwise OR with 0x100 so _itot_s() will output 3 hex digits
-                       _itot_s(0x100 | c, p + n - 4, 4, 16);
+                       p[n - 4 + 1] = _T("0123456789ABCDEF")[(c >> 4) & 0xf];
+                       p[n - 4 + 2] = _T("0123456789ABCDEF")[c & 0xf];
                        // Replace terminating zero with leadout character
                        p[n - 1] = _T('\\');
                        // Prepare to replace 1st hex digit with leadin character