[freetype2] master 0d053ba: Fix runtime errors found by clang's sanitizer (#47082).

[Werner LEMBERG]

branch: master
commit 0d053bac8423f42c8c99d4068abd718e02d25e17
Author: Werner Lemberg <address@hidden>
Commit: Werner Lemberg <address@hidden>

    Fix runtime errors found by clang's sanitizer (#47082).
    
    * src/base/ftobjs.c (FT_Render_Glyph_Internal), src/base/ftoutln.c
    (FT_Outline_Copy), src/cache/ftcsbits.c (ftc_sbit_copy_bitmap):
    Properly handle empty input buffer.
---
 ChangeLog            |   10 +++++++++-
 src/base/ftobjs.c    |    3 ++-
 src/base/ftoutln.c   |   11 +++++++----
 src/cache/ftcsbits.c |    2 ++
 4 files changed, 20 insertions(+), 6 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index a045395..5031a00 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,13 @@
 2016-02-07  Werner Lemberg  <address@hidden>
 
+       Fix runtime errors found by clang's sanitizer (#47082).
+
+       * src/base/ftobjs.c (FT_Render_Glyph_Internal), src/base/ftoutln.c
+       (FT_Outline_Copy), src/cache/ftcsbits.c (ftc_sbit_copy_bitmap):
+       Properly handle empty input buffer.
+
+2016-02-07  Werner Lemberg  <address@hidden>
+
        [cff] Minor.
 
        * src/cff/cffgload.c (cff_decoder_parse_charstrings) <cff_op_sqrt>:
@@ -76,7 +84,7 @@
        (FT_Face_CheckTrueTypePatents, FT_Face_SetUnpatentedHinting):
        Replace code with dummies.
 
-       * src/truetype/ttobjs.c (tt_face_init): Remove now defunct code. 
+       * src/truetype/ttobjs.c (tt_face_init): Remove now defunct code.
        * src/truetype/ttobjs.h (TT_GraphicsState): Remove `both_x_axis'
        field.
 
diff --git a/src/base/ftobjs.c b/src/base/ftobjs.c
index a68f21b..fa05347 100644
--- a/src/base/ftobjs.c
+++ b/src/base/ftobjs.c
@@ -4201,7 +4201,8 @@
 
 
           MD5_Init( &ctx );
-          MD5_Update( &ctx, bitmap.buffer, rows * pitch );
+          if ( bitmap.buffer )
+            MD5_Update( &ctx, bitmap.buffer, rows * pitch );
           MD5_Final( md5, &ctx );
 
           FT_TRACE3(( "MD5 checksum for %dx%d bitmap:\n"
diff --git a/src/base/ftoutln.c b/src/base/ftoutln.c
index 912dfd3..fa2d2cf 100644
--- a/src/base/ftoutln.c
+++ b/src/base/ftoutln.c
@@ -415,11 +415,14 @@
     if ( source == target )
       return FT_Err_Ok;
 
-    FT_ARRAY_COPY( target->points, source->points, source->n_points );
-
-    FT_ARRAY_COPY( target->tags, source->tags, source->n_points );
+    if ( source->n_points )
+    {
+      FT_ARRAY_COPY( target->points, source->points, source->n_points );
+      FT_ARRAY_COPY( target->tags,   source->tags,   source->n_points );
+    }
 
-    FT_ARRAY_COPY( target->contours, source->contours, source->n_contours );
+    if ( source->n_contours )
+      FT_ARRAY_COPY( target->contours, source->contours, source->n_contours );
 
     /* copy all flags, except the `FT_OUTLINE_OWNER' one */
     is_owner      = target->flags & FT_OUTLINE_OWNER;
diff --git a/src/cache/ftcsbits.c b/src/cache/ftcsbits.c
index e6b8865..d6f1ddc 100644
--- a/src/cache/ftcsbits.c
+++ b/src/cache/ftcsbits.c
@@ -53,6 +53,8 @@
       pitch = -pitch;
 
     size = (FT_ULong)pitch * bitmap->rows;
+    if ( !size )
+      return FT_Err_Ok;
 
     if ( !FT_ALLOC( sbit->buffer, size ) )
       FT_MEM_COPY( sbit->buffer, bitmap->buffer, size );