[freetype2] master 78cded2 1/2: Fix cmap format 2 handling (#53320).

[Werner LEMBERG]

branch: master
commit 78cded2c5c687d06c5b74b308fb54af7f807dc0d
Author: Werner Lemberg <address@hidden>
Commit: Werner Lemberg <address@hidden>

    Fix cmap format 2 handling (#53320).
    
    The patch introduced for #52646 was not correct.
    
    * src/sfnt/ttcmap.c (tt_cmap2_char_next): Adjust condition.
---
 ChangeLog         |  8 ++++++++
 src/sfnt/ttcmap.c | 15 +++++++--------
 2 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 25639ae..65bc409 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+2018-03-13  Werner Lemberg  <address@hidden>
+
+       Fix cmap format 2 handling (#53320).
+
+       The patch introduced for #52646 was not correct.
+
+       * src/sfnt/ttcmap.c (tt_cmap2_char_next): Adjust condition.
+
 2018-03-10  Nikolaus Waxweiler  <address@hidden>
 
        * CMakeLists.txt (BASE_SRCS): Update to changes from 2018-03-05.
diff --git a/src/sfnt/ttcmap.c b/src/sfnt/ttcmap.c
index 8cc70f7..58b49c9 100644
--- a/src/sfnt/ttcmap.c
+++ b/src/sfnt/ttcmap.c
@@ -549,19 +549,18 @@
             }
           }
         }
+
+        /* if unsuccessful, avoid `charcode' leaving */
+        /* the current 256-character block           */
+        if ( count )
+          charcode--;
       }
 
-      /* If `charcode' is <= 0xFF, retry with `charcode + 1'.  If        */
-      /* `charcode' is 0x100 after the loop, do nothing since we have    */
-      /* just reached the first sub-header for two-byte character codes. */
-      /*                                                                 */
-      /* For all other cases, we jump to the next sub-header and adjust  */
-      /* `charcode' accordingly.                                         */
+      /* If `charcode' is <= 0xFF, retry with `charcode + 1'.      */
+      /* Otherwise jump to the next 256-character block and retry. */
     Next_SubHeader:
       if ( charcode <= 0xFF )
         charcode++;
-      else if ( charcode == 0x100 )
-        ;
       else
         charcode = FT_PAD_FLOOR( charcode, 0x100 ) + 0x100;
     }