Update harfbuzz-ng to 0.9.14 from 0.9.10

third_party/harfbuzz-ng/src/hb-blob.h

 /*
  * Copyright © 2009  Red Hat, Inc.
  *
  *  This is part of HarfBuzz, a text shaping library.
  *
  * Permission is hereby granted, without written agreement and without
  * license or royalty fees, to use, copy, modify, and distribute this
  * software and its documentation for any purpose, provided that the
  * above copyright notice and the following two paragraphs appear in
  * all copies of this software.
@@ skipping 18 matching lines @@
 #endif
 
 #ifndef HB_BLOB_H
 #define HB_BLOB_H
 
 #include "hb-common.h"
 
 HB_BEGIN_DECLS
 
 
+/*
+ * Note re various memory-modes:
+ *
+ * - In no case shall the HarfBuzz client modify memory
+ *   that is passed to HarfBuzz in a blob.  If there is
+ *   any such possibility, MODE_DUPLICATE should be used
+ *   such that HarfBuzz makes a copy immediately,
+ *
+ * - Use MODE_READONLY otherse, unless you really really
+ *   really know what you are doing,
+ *
+ * - MODE_WRITABLE is appropriate if you relaly made a
+ *   copy of data solely for the purpose of passing to
+ *   HarfBuzz and doing that just once (no reuse!),
+ *
+ * - If the font is mmap()ed, it's ok to use
+ *   READONLY_MAY_MAKE_WRITABLE, however, there were
+ *   design problems with that mode, so HarfBuzz do not
+ *   really use it anymore.  If not sure, use MODE_READONLY.
+ */
 typedef enum {
   HB_MEMORY_MODE_DUPLICATE,
   HB_MEMORY_MODE_READONLY,
   HB_MEMORY_MODE_WRITABLE,
   HB_MEMORY_MODE_READONLY_MAY_MAKE_WRITABLE
 } hb_memory_mode_t;
 
 typedef struct hb_blob_t hb_blob_t;
 
 hb_blob_t *
 hb_blob_create (const char        *data,
                 unsigned int       length,
                 hb_memory_mode_t   mode,
                 void              *user_data,
                 hb_destroy_func_t  destroy);
 
+/* Always creates with MEMORY_MODE_READONLY.
+ * Even if the parent blob is writable, we don't
+ * want the user of the sub-blob to be able to
+ * modify the parent data as that data may be
+ * shared among multiple sub-blobs.
+ */
 hb_blob_t *
 hb_blob_create_sub_blob (hb_blob_t    *parent,
                          unsigned int  offset,
                          unsigned int  length);
 
 hb_blob_t *
 hb_blob_get_empty (void);
 
 hb_blob_t *
 hb_blob_reference (hb_blob_t *blob);
@@ skipping 27 matching lines @@
 const char *
 hb_blob_get_data (hb_blob_t *blob, unsigned int *length);
 
 char *
 hb_blob_get_data_writable (hb_blob_t *blob, unsigned int *length);
 
 
 HB_END_DECLS
 
 #endif /* HB_BLOB_H */