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 #if !defined(HB_H_IN) && !defined(HB_NO_SINGLE_HEADER_ERROR) 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 * hb_memory_mode_t: 41 * @HB_MEMORY_MODE_DUPLICATE: HarfBuzz immediately makes a copy of the data. 42 * @HB_MEMORY_MODE_READONLY: HarfBuzz client will never modify the data, 43 * and HarfBuzz will never modify the data. 44 * @HB_MEMORY_MODE_WRITABLE: HarfBuzz client made a copy of the data solely 45 * for HarfBuzz, so HarfBuzz may modify the data. 46 * @HB_MEMORY_MODE_READONLY_MAY_MAKE_WRITABLE: See above 47 * 48 * Data type holding the memory modes available to 49 * client programs. 50 * 51 * Regarding these various memory-modes: 52 * 53 * - In no case shall the HarfBuzz client modify memory 54 * that is passed to HarfBuzz in a blob. If there is 55 * any such possibility, @HB_MEMORY_MODE_DUPLICATE should be used 56 * such that HarfBuzz makes a copy immediately, 57 * 58 * - Use @HB_MEMORY_MODE_READONLY otherwise, unless you really really 59 * really know what you are doing, 60 * 61 * - @HB_MEMORY_MODE_WRITABLE is appropriate if you really made a 62 * copy of data solely for the purpose of passing to 63 * HarfBuzz and doing that just once (no reuse!), 64 * 65 * - If the font is mmap()ed, it's okay to use 66 * @HB_MEMORY_READONLY_MAY_MAKE_WRITABLE, however, using that mode 67 * correctly is very tricky. Use @HB_MEMORY_MODE_READONLY instead. 68 **/ 69 typedef enum { 70 HB_MEMORY_MODE_DUPLICATE, 71 HB_MEMORY_MODE_READONLY, 72 HB_MEMORY_MODE_WRITABLE, 73 HB_MEMORY_MODE_READONLY_MAY_MAKE_WRITABLE 74 } hb_memory_mode_t; 75 76 /** 77 * hb_blob_t: 78 * 79 * Data type for blobs. A blob wraps a chunk of binary 80 * data and facilitates its lifecycle management between 81 * a client program and HarfBuzz. 82 * 83 **/ 84 typedef struct hb_blob_t hb_blob_t; 85 86 HB_EXTERN hb_blob_t * 87 hb_blob_create (const char *data, 88 unsigned int length, 89 hb_memory_mode_t mode, 90 void *user_data, 91 hb_destroy_func_t destroy); 92 93 HB_EXTERN hb_blob_t * 94 hb_blob_create_from_file (const char *file_name); 95 96 /* Always creates with MEMORY_MODE_READONLY. 97 * Even if the parent blob is writable, we don't 98 * want the user of the sub-blob to be able to 99 * modify the parent data as that data may be 100 * shared among multiple sub-blobs. 101 */ 102 HB_EXTERN hb_blob_t * 103 hb_blob_create_sub_blob (hb_blob_t *parent, 104 unsigned int offset, 105 unsigned int length); 106 107 HB_EXTERN hb_blob_t * 108 hb_blob_copy_writable_or_fail (hb_blob_t *blob); 109 110 HB_EXTERN hb_blob_t * 111 hb_blob_get_empty (void); 112 113 HB_EXTERN hb_blob_t * 114 hb_blob_reference (hb_blob_t *blob); 115 116 HB_EXTERN void 117 hb_blob_destroy (hb_blob_t *blob); 118 119 HB_EXTERN hb_bool_t 120 hb_blob_set_user_data (hb_blob_t *blob, 121 hb_user_data_key_t *key, 122 void * data, 123 hb_destroy_func_t destroy, 124 hb_bool_t replace); 125 126 127 HB_EXTERN void * 128 hb_blob_get_user_data (hb_blob_t *blob, 129 hb_user_data_key_t *key); 130 131 132 HB_EXTERN void 133 hb_blob_make_immutable (hb_blob_t *blob); 134 135 HB_EXTERN hb_bool_t 136 hb_blob_is_immutable (hb_blob_t *blob); 137 138 139 HB_EXTERN unsigned int 140 hb_blob_get_length (hb_blob_t *blob); 141 142 HB_EXTERN const char * 143 hb_blob_get_data (hb_blob_t *blob, unsigned int *length); 144 145 HB_EXTERN char * 146 hb_blob_get_data_writable (hb_blob_t *blob, unsigned int *length); 147 148 HB_END_DECLS 149 150 #endif /* HB_BLOB_H */ 151