commit 54cf108c846c69715533292c9c2e3269850b8219
author Vojtech Bocek <vbocek@gmail.com> Sun Mar 15 16:50:26 2015 +0100
committer Dees Troy <dees_troy@teamw.in> Thu Mar 19 16:50:08 2015 +0100
tree f41391a656590d74f9d2682eb4db11f907be4f3b
parent a482f253453a50fc8c12d03205e12b577ef803d6

Fix invalid memory access when rendering a ttf glyph with 'left' < 0

* Fixes for example 'j' in Roboto-Regular

Change-Id: I0cf778c99f391900e164be743165cf8aad891020
Signed-off-by: Vojtech Bocek <vbocek@gmail.com>

minuitwrp/truetype.c

diff --git a/minuitwrp/truetype.c b/minuitwrp/truetype.c
index e8a1629..a286449 100644
--- a/minuitwrp/truetype.c
+++ b/minuitwrp/truetype.c
@@ -369,6 +369,11 @@
 
     dest_itr += (offY + base - glyph->top)*dest->stride + (offX + glyph->left);
 
+    // FIXME: if glyph->left is negative and everything else is 0 (e.g. letter 'j' in Roboto-Regular),
+    // the result might end up being before the buffer - I'm not sure how to properly handle this.
+    if(dest_itr < dest->data)
+        dest_itr = dest->data;
+
     for(y = 0; y < glyph->bitmap.rows; ++y)
     {
         memcpy(dest_itr, src_itr, glyph->bitmap.width);