[PATCH] dwrite: Handle fonts with broken usWinDescent values

[Nikolay Sivov]

---
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From 8f47a976d7bb9dab8c425c06e57488e8664a74a1 Mon Sep 17 00:00:00 2001
From: Nikolay Sivov <nsivov at codeweavers.com>
Date: Sun, 27 Sep 2015 22:48:38 +0300
Subject: [PATCH] dwrite: Handle fonts with broken usWinDescent values

Signed-off-by: Nikolay Sivov <nsivov at codeweavers.com>
---
 dlls/dwrite/opentype.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/dlls/dwrite/opentype.c b/dlls/dwrite/opentype.c
index fd471ef..82e0a9c 100644
--- a/dlls/dwrite/opentype.c
+++ b/dlls/dwrite/opentype.c
@@ -960,7 +960,9 @@ void opentype_get_font_metrics(IDWriteFontFileStream *stream, DWRITE_FONT_FACE_T
         USHORT version = GET_BE_WORD(tt_os2->version);
 
         metrics->ascent  = GET_BE_WORD(tt_os2->usWinAscent);
-        metrics->descent = GET_BE_WORD(tt_os2->usWinDescent);
+        /* Some fonts have usWinDescent value stored as signed short, which could be wrongly
+           interpreted as large unsigned value. */
+        metrics->descent = abs((SHORT)GET_BE_WORD(tt_os2->usWinDescent));
 
         /* line gap is estimated using two sets of ascender/descender values and 'hhea' line gap */
         if (tt_hhea) {
-- 
2.5.3