1/*
2 * Copyright © 2009  Red Hat, Inc.
3 *
4 *  This is part of HarfBuzz, a text shaping library.
5 *
6 * Permission is hereby granted, without written agreement and without
7 * license or royalty fees, to use, copy, modify, and distribute this
8 * software and its documentation for any purpose, provided that the
9 * above copyright notice and the following two paragraphs appear in
10 * all copies of this software.
11 *
12 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
13 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
14 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
15 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
16 * DAMAGE.
17 *
18 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
19 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
20 * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
21 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
22 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
23 *
24 * Red Hat Author(s): Behdad Esfahbod
25 */
26
27#ifndef HB_H_IN
28#error "Include <hb.h> instead."
29#endif
30
31#ifndef HB_BLOB_H
32#define HB_BLOB_H
33
34#include "hb-common.h"
35
36HB_BEGIN_DECLS
37
38
39/*
40 * Note re various memory-modes:
41 *
42 * - In no case shall the HarfBuzz client modify memory
43 *   that is passed to HarfBuzz in a blob.  If there is
44 *   any such possibility, MODE_DUPLICATE should be used
45 *   such that HarfBuzz makes a copy immediately,
46 *
47 * - Use MODE_READONLY otherse, unless you really really
48 *   really know what you are doing,
49 *
50 * - MODE_WRITABLE is appropriate if you really made a
51 *   copy of data solely for the purpose of passing to
52 *   HarfBuzz and doing that just once (no reuse!),
53 *
54 * - If the font is mmap()ed, it's ok to use
55 *   READONLY_MAY_MAKE_WRITABLE, however, using that mode
56 *   correctly is very tricky.  Use MODE_READONLY instead.
57 */
58typedef enum {
59  HB_MEMORY_MODE_DUPLICATE,
60  HB_MEMORY_MODE_READONLY,
61  HB_MEMORY_MODE_WRITABLE,
62  HB_MEMORY_MODE_READONLY_MAY_MAKE_WRITABLE
63} hb_memory_mode_t;
64
65typedef struct hb_blob_t hb_blob_t;
66
67hb_blob_t *
68hb_blob_create (const char        *data,
69		unsigned int       length,
70		hb_memory_mode_t   mode,
71		void              *user_data,
72		hb_destroy_func_t  destroy);
73
74/* Always creates with MEMORY_MODE_READONLY.
75 * Even if the parent blob is writable, we don't
76 * want the user of the sub-blob to be able to
77 * modify the parent data as that data may be
78 * shared among multiple sub-blobs.
79 */
80hb_blob_t *
81hb_blob_create_sub_blob (hb_blob_t    *parent,
82			 unsigned int  offset,
83			 unsigned int  length);
84
85hb_blob_t *
86hb_blob_get_empty (void);
87
88hb_blob_t *
89hb_blob_reference (hb_blob_t *blob);
90
91void
92hb_blob_destroy (hb_blob_t *blob);
93
94hb_bool_t
95hb_blob_set_user_data (hb_blob_t          *blob,
96		       hb_user_data_key_t *key,
97		       void *              data,
98		       hb_destroy_func_t   destroy,
99		       hb_bool_t           replace);
100
101
102void *
103hb_blob_get_user_data (hb_blob_t          *blob,
104		       hb_user_data_key_t *key);
105
106
107void
108hb_blob_make_immutable (hb_blob_t *blob);
109
110hb_bool_t
111hb_blob_is_immutable (hb_blob_t *blob);
112
113
114unsigned int
115hb_blob_get_length (hb_blob_t *blob);
116
117const char *
118hb_blob_get_data (hb_blob_t *blob, unsigned int *length);
119
120char *
121hb_blob_get_data_writable (hb_blob_t *blob, unsigned int *length);
122
123
124HB_END_DECLS
125
126#endif /* HB_BLOB_H */
127