1 /*
2  * Copyright © 2009  Red Hat, Inc.
3  * Copyright © 2018  Google, Inc.
4  *
5  *  This is part of HarfBuzz, a text shaping library.
6  *
7  * Permission is hereby granted, without written agreement and without
8  * license or royalty fees, to use, copy, modify, and distribute this
9  * software and its documentation for any purpose, provided that the
10  * above copyright notice and the following two paragraphs appear in
11  * all copies of this software.
12  *
13  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
14  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
15  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
16  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
17  * DAMAGE.
18  *
19  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
20  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
21  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
22  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
23  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
24  *
25  * Red Hat Author(s): Behdad Esfahbod
26  * Google Author(s): Behdad Esfahbod
27  */
28 
29 #ifndef HB_BLOB_HH
30 #define HB_BLOB_HH
31 
32 #include "hb.hh"
33 
34 
35 /*
36  * hb_blob_t
37  */
38 
39 struct hb_blob_t
40 {
fini_shallowhb_blob_t41   void fini_shallow () { destroy_user_data (); }
42 
destroy_user_datahb_blob_t43   void destroy_user_data ()
44   {
45     if (destroy)
46     {
47       destroy (user_data);
48       user_data = nullptr;
49       destroy = nullptr;
50     }
51   }
52 
53   HB_INTERNAL bool try_make_writable ();
54   HB_INTERNAL bool try_make_writable_inplace ();
55   HB_INTERNAL bool try_make_writable_inplace_unix ();
56 
57   template <typename Type>
ashb_blob_t58   const Type* as () const
59   {
60     return length < hb_null_size (Type) ? &Null(Type) : reinterpret_cast<const Type *> (data);
61   }
as_byteshb_blob_t62   hb_bytes_t as_bytes () const
63   { return hb_bytes_t (data, length); }
64 
65   public:
66   hb_object_header_t header;
67 
68   const char *data;
69   unsigned int length;
70   hb_memory_mode_t mode;
71 
72   void *user_data;
73   hb_destroy_func_t destroy;
74 };
75 
76 
77 /*
78  * hb_blob_ptr_t
79  */
80 
81 template <typename P>
82 struct hb_blob_ptr_t
83 {
84   typedef typename hb_remove_pointer (P) T;
85 
hb_blob_ptr_thb_blob_ptr_t86   hb_blob_ptr_t (hb_blob_t *b_ = nullptr) : b (b_) {}
operator =hb_blob_ptr_t87   hb_blob_t * operator = (hb_blob_t *b_) { return b = b_; }
operator ->hb_blob_ptr_t88   const T * operator -> () const { return get (); }
operator *hb_blob_ptr_t89   const T & operator * () const  { return *get (); }
operator const C*hb_blob_ptr_t90   template <typename C> operator const C * () const { return get (); }
operator const char*hb_blob_ptr_t91   operator const char * () const { return (const char *) get (); }
gethb_blob_ptr_t92   const T * get () const { return b->as<T> (); }
get_blobhb_blob_ptr_t93   hb_blob_t * get_blob () const { return b.get_raw (); }
get_lengthhb_blob_ptr_t94   unsigned int get_length () const { return b.get ()->length; }
destroyhb_blob_ptr_t95   void destroy () { hb_blob_destroy (b.get ()); b = nullptr; }
96 
97   hb_nonnull_ptr_t<hb_blob_t> b;
98 };
99 
100 
101 #endif /* HB_BLOB_HH */
102