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 

    36 HB_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  */

    58 typedef 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 

    65 typedef struct hb_blob_t hb_blob_t;

    66 

    67 hb_blob_t *

    68 hb_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  */

    80 hb_blob_t *

    81 hb_blob_create_sub_blob (hb_blob_t    *parent,

    82                          unsigned int  offset,

    83                          unsigned int  length);

    84 

    85 hb_blob_t *

    86 hb_blob_get_empty (void);

    87 

    88 hb_blob_t *

    89 hb_blob_reference (hb_blob_t *blob);

    90 

    91 void

    92 hb_blob_destroy (hb_blob_t *blob);

    93 

    94 hb_bool_t

    95 hb_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 

   102 void *

   103 hb_blob_get_user_data (hb_blob_t          *blob,

   104                        hb_user_data_key_t *key);

   105 

   106 

   107 void

   108 hb_blob_make_immutable (hb_blob_t *blob);

   109 

   110 hb_bool_t

   111 hb_blob_is_immutable (hb_blob_t *blob);

   112 

   113 

   114 unsigned int

   115 hb_blob_get_length (hb_blob_t *blob);

   116 

   117 const char *

   118 hb_blob_get_data (hb_blob_t *blob, unsigned int *length);

   119 

   120 char *

   121 hb_blob_get_data_writable (hb_blob_t *blob, unsigned int *length);

   122 

   123 

   124 HB_END_DECLS

   125 

   126 #endif /* HB_BLOB_H */