Imported Upstream version 1.8.1
[platform/upstream/harfbuzz.git] / src / hb-common.h
1 /*
2  * Copyright © 2007,2008,2009  Red Hat, Inc.
3  * Copyright © 2011,2012  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_H_IN
30 #error "Include <hb.h> instead."
31 #endif
32
33 #ifndef HB_COMMON_H
34 #define HB_COMMON_H
35
36 #ifndef HB_BEGIN_DECLS
37 # ifdef __cplusplus
38 #  define HB_BEGIN_DECLS        extern "C" {
39 #  define HB_END_DECLS          }
40 # else /* !__cplusplus */
41 #  define HB_BEGIN_DECLS
42 #  define HB_END_DECLS
43 # endif /* !__cplusplus */
44 #endif
45
46 #if defined (_SVR4) || defined (SVR4) || defined (__OpenBSD__) || \
47     defined (_sgi) || defined (__sun) || defined (sun) || \
48     defined (__digital__) || defined (__HP_cc)
49 #  include <inttypes.h>
50 #elif defined (_AIX)
51 #  include <sys/inttypes.h>
52 #elif defined (_MSC_VER) && _MSC_VER < 1600
53 /* VS 2010 (_MSC_VER 1600) has stdint.h */
54 typedef __int8 int8_t;
55 typedef unsigned __int8 uint8_t;
56 typedef __int16 int16_t;
57 typedef unsigned __int16 uint16_t;
58 typedef __int32 int32_t;
59 typedef unsigned __int32 uint32_t;
60 typedef __int64 int64_t;
61 typedef unsigned __int64 uint64_t;
62 #else
63 #  include <stdint.h>
64 #endif
65
66 HB_BEGIN_DECLS
67
68
69 typedef int hb_bool_t;
70
71 typedef uint32_t hb_codepoint_t;
72 typedef int32_t hb_position_t;
73 typedef uint32_t hb_mask_t;
74
75 typedef union _hb_var_int_t {
76   uint32_t u32;
77   int32_t i32;
78   uint16_t u16[2];
79   int16_t i16[2];
80   uint8_t u8[4];
81   int8_t i8[4];
82 } hb_var_int_t;
83
84
85 /* hb_tag_t */
86
87 typedef uint32_t hb_tag_t;
88
89 #define HB_TAG(c1,c2,c3,c4) ((hb_tag_t)((((uint8_t)(c1))<<24)|(((uint8_t)(c2))<<16)|(((uint8_t)(c3))<<8)|((uint8_t)(c4))))
90 #define HB_UNTAG(tag)   ((uint8_t)((tag)>>24)), ((uint8_t)((tag)>>16)), ((uint8_t)((tag)>>8)), ((uint8_t)(tag))
91
92 #define HB_TAG_NONE HB_TAG(0,0,0,0)
93 #define HB_TAG_MAX HB_TAG(0xff,0xff,0xff,0xff)
94 #define HB_TAG_MAX_SIGNED HB_TAG(0x7f,0xff,0xff,0xff)
95
96 /* len=-1 means str is NUL-terminated. */
97 HB_EXTERN hb_tag_t
98 hb_tag_from_string (const char *str, int len);
99
100 /* buf should have 4 bytes. */
101 HB_EXTERN void
102 hb_tag_to_string (hb_tag_t tag, char *buf);
103
104
105 /**
106  * hb_direction_t:
107  * @HB_DIRECTION_INVALID: Initial, unset direction.
108  * @HB_DIRECTION_LTR: Text is set horizontally from left to right.
109  * @HB_DIRECTION_RTL: Text is set horizontally from right to left.
110  * @HB_DIRECTION_TTB: Text is set vertically from top to bottom.
111  * @HB_DIRECTION_BTT: Text is set vertically from bottom to top.
112  */
113 typedef enum {
114   HB_DIRECTION_INVALID = 0,
115   HB_DIRECTION_LTR = 4,
116   HB_DIRECTION_RTL,
117   HB_DIRECTION_TTB,
118   HB_DIRECTION_BTT
119 } hb_direction_t;
120
121 /* len=-1 means str is NUL-terminated */
122 HB_EXTERN hb_direction_t
123 hb_direction_from_string (const char *str, int len);
124
125 HB_EXTERN const char *
126 hb_direction_to_string (hb_direction_t direction);
127
128 #define HB_DIRECTION_IS_VALID(dir)      ((((unsigned int) (dir)) & ~3U) == 4)
129 /* Direction must be valid for the following */
130 #define HB_DIRECTION_IS_HORIZONTAL(dir) ((((unsigned int) (dir)) & ~1U) == 4)
131 #define HB_DIRECTION_IS_VERTICAL(dir)   ((((unsigned int) (dir)) & ~1U) == 6)
132 #define HB_DIRECTION_IS_FORWARD(dir)    ((((unsigned int) (dir)) & ~2U) == 4)
133 #define HB_DIRECTION_IS_BACKWARD(dir)   ((((unsigned int) (dir)) & ~2U) == 5)
134 #define HB_DIRECTION_REVERSE(dir)       ((hb_direction_t) (((unsigned int) (dir)) ^ 1))
135
136
137 /* hb_language_t */
138
139 typedef const struct hb_language_impl_t *hb_language_t;
140
141 HB_EXTERN hb_language_t
142 hb_language_from_string (const char *str, int len);
143
144 HB_EXTERN const char *
145 hb_language_to_string (hb_language_t language);
146
147 #define HB_LANGUAGE_INVALID ((hb_language_t) 0)
148
149 HB_EXTERN hb_language_t
150 hb_language_get_default (void);
151
152
153 /* hb_script_t */
154
155 /* https://unicode.org/iso15924/ */
156 /* https://docs.google.com/spreadsheets/d/1Y90M0Ie3MUJ6UVCRDOypOtijlMDLNNyyLk36T6iMu0o */
157 /* Unicode Character Database property: Script (sc) */
158 typedef enum
159 {
160   /*1.1*/ HB_SCRIPT_COMMON                      = HB_TAG ('Z','y','y','y'),
161   /*1.1*/ HB_SCRIPT_INHERITED                   = HB_TAG ('Z','i','n','h'),
162   /*5.0*/ HB_SCRIPT_UNKNOWN                     = HB_TAG ('Z','z','z','z'),
163
164   /*1.1*/ HB_SCRIPT_ARABIC                      = HB_TAG ('A','r','a','b'),
165   /*1.1*/ HB_SCRIPT_ARMENIAN                    = HB_TAG ('A','r','m','n'),
166   /*1.1*/ HB_SCRIPT_BENGALI                     = HB_TAG ('B','e','n','g'),
167   /*1.1*/ HB_SCRIPT_CYRILLIC                    = HB_TAG ('C','y','r','l'),
168   /*1.1*/ HB_SCRIPT_DEVANAGARI                  = HB_TAG ('D','e','v','a'),
169   /*1.1*/ HB_SCRIPT_GEORGIAN                    = HB_TAG ('G','e','o','r'),
170   /*1.1*/ HB_SCRIPT_GREEK                       = HB_TAG ('G','r','e','k'),
171   /*1.1*/ HB_SCRIPT_GUJARATI                    = HB_TAG ('G','u','j','r'),
172   /*1.1*/ HB_SCRIPT_GURMUKHI                    = HB_TAG ('G','u','r','u'),
173   /*1.1*/ HB_SCRIPT_HANGUL                      = HB_TAG ('H','a','n','g'),
174   /*1.1*/ HB_SCRIPT_HAN                         = HB_TAG ('H','a','n','i'),
175   /*1.1*/ HB_SCRIPT_HEBREW                      = HB_TAG ('H','e','b','r'),
176   /*1.1*/ HB_SCRIPT_HIRAGANA                    = HB_TAG ('H','i','r','a'),
177   /*1.1*/ HB_SCRIPT_KANNADA                     = HB_TAG ('K','n','d','a'),
178   /*1.1*/ HB_SCRIPT_KATAKANA                    = HB_TAG ('K','a','n','a'),
179   /*1.1*/ HB_SCRIPT_LAO                         = HB_TAG ('L','a','o','o'),
180   /*1.1*/ HB_SCRIPT_LATIN                       = HB_TAG ('L','a','t','n'),
181   /*1.1*/ HB_SCRIPT_MALAYALAM                   = HB_TAG ('M','l','y','m'),
182   /*1.1*/ HB_SCRIPT_ORIYA                       = HB_TAG ('O','r','y','a'),
183   /*1.1*/ HB_SCRIPT_TAMIL                       = HB_TAG ('T','a','m','l'),
184   /*1.1*/ HB_SCRIPT_TELUGU                      = HB_TAG ('T','e','l','u'),
185   /*1.1*/ HB_SCRIPT_THAI                        = HB_TAG ('T','h','a','i'),
186
187   /*2.0*/ HB_SCRIPT_TIBETAN                     = HB_TAG ('T','i','b','t'),
188
189   /*3.0*/ HB_SCRIPT_BOPOMOFO                    = HB_TAG ('B','o','p','o'),
190   /*3.0*/ HB_SCRIPT_BRAILLE                     = HB_TAG ('B','r','a','i'),
191   /*3.0*/ HB_SCRIPT_CANADIAN_SYLLABICS          = HB_TAG ('C','a','n','s'),
192   /*3.0*/ HB_SCRIPT_CHEROKEE                    = HB_TAG ('C','h','e','r'),
193   /*3.0*/ HB_SCRIPT_ETHIOPIC                    = HB_TAG ('E','t','h','i'),
194   /*3.0*/ HB_SCRIPT_KHMER                       = HB_TAG ('K','h','m','r'),
195   /*3.0*/ HB_SCRIPT_MONGOLIAN                   = HB_TAG ('M','o','n','g'),
196   /*3.0*/ HB_SCRIPT_MYANMAR                     = HB_TAG ('M','y','m','r'),
197   /*3.0*/ HB_SCRIPT_OGHAM                       = HB_TAG ('O','g','a','m'),
198   /*3.0*/ HB_SCRIPT_RUNIC                       = HB_TAG ('R','u','n','r'),
199   /*3.0*/ HB_SCRIPT_SINHALA                     = HB_TAG ('S','i','n','h'),
200   /*3.0*/ HB_SCRIPT_SYRIAC                      = HB_TAG ('S','y','r','c'),
201   /*3.0*/ HB_SCRIPT_THAANA                      = HB_TAG ('T','h','a','a'),
202   /*3.0*/ HB_SCRIPT_YI                          = HB_TAG ('Y','i','i','i'),
203
204   /*3.1*/ HB_SCRIPT_DESERET                     = HB_TAG ('D','s','r','t'),
205   /*3.1*/ HB_SCRIPT_GOTHIC                      = HB_TAG ('G','o','t','h'),
206   /*3.1*/ HB_SCRIPT_OLD_ITALIC                  = HB_TAG ('I','t','a','l'),
207
208   /*3.2*/ HB_SCRIPT_BUHID                       = HB_TAG ('B','u','h','d'),
209   /*3.2*/ HB_SCRIPT_HANUNOO                     = HB_TAG ('H','a','n','o'),
210   /*3.2*/ HB_SCRIPT_TAGALOG                     = HB_TAG ('T','g','l','g'),
211   /*3.2*/ HB_SCRIPT_TAGBANWA                    = HB_TAG ('T','a','g','b'),
212
213   /*4.0*/ HB_SCRIPT_CYPRIOT                     = HB_TAG ('C','p','r','t'),
214   /*4.0*/ HB_SCRIPT_LIMBU                       = HB_TAG ('L','i','m','b'),
215   /*4.0*/ HB_SCRIPT_LINEAR_B                    = HB_TAG ('L','i','n','b'),
216   /*4.0*/ HB_SCRIPT_OSMANYA                     = HB_TAG ('O','s','m','a'),
217   /*4.0*/ HB_SCRIPT_SHAVIAN                     = HB_TAG ('S','h','a','w'),
218   /*4.0*/ HB_SCRIPT_TAI_LE                      = HB_TAG ('T','a','l','e'),
219   /*4.0*/ HB_SCRIPT_UGARITIC                    = HB_TAG ('U','g','a','r'),
220
221   /*4.1*/ HB_SCRIPT_BUGINESE                    = HB_TAG ('B','u','g','i'),
222   /*4.1*/ HB_SCRIPT_COPTIC                      = HB_TAG ('C','o','p','t'),
223   /*4.1*/ HB_SCRIPT_GLAGOLITIC                  = HB_TAG ('G','l','a','g'),
224   /*4.1*/ HB_SCRIPT_KHAROSHTHI                  = HB_TAG ('K','h','a','r'),
225   /*4.1*/ HB_SCRIPT_NEW_TAI_LUE                 = HB_TAG ('T','a','l','u'),
226   /*4.1*/ HB_SCRIPT_OLD_PERSIAN                 = HB_TAG ('X','p','e','o'),
227   /*4.1*/ HB_SCRIPT_SYLOTI_NAGRI                = HB_TAG ('S','y','l','o'),
228   /*4.1*/ HB_SCRIPT_TIFINAGH                    = HB_TAG ('T','f','n','g'),
229
230   /*5.0*/ HB_SCRIPT_BALINESE                    = HB_TAG ('B','a','l','i'),
231   /*5.0*/ HB_SCRIPT_CUNEIFORM                   = HB_TAG ('X','s','u','x'),
232   /*5.0*/ HB_SCRIPT_NKO                         = HB_TAG ('N','k','o','o'),
233   /*5.0*/ HB_SCRIPT_PHAGS_PA                    = HB_TAG ('P','h','a','g'),
234   /*5.0*/ HB_SCRIPT_PHOENICIAN                  = HB_TAG ('P','h','n','x'),
235
236   /*5.1*/ HB_SCRIPT_CARIAN                      = HB_TAG ('C','a','r','i'),
237   /*5.1*/ HB_SCRIPT_CHAM                        = HB_TAG ('C','h','a','m'),
238   /*5.1*/ HB_SCRIPT_KAYAH_LI                    = HB_TAG ('K','a','l','i'),
239   /*5.1*/ HB_SCRIPT_LEPCHA                      = HB_TAG ('L','e','p','c'),
240   /*5.1*/ HB_SCRIPT_LYCIAN                      = HB_TAG ('L','y','c','i'),
241   /*5.1*/ HB_SCRIPT_LYDIAN                      = HB_TAG ('L','y','d','i'),
242   /*5.1*/ HB_SCRIPT_OL_CHIKI                    = HB_TAG ('O','l','c','k'),
243   /*5.1*/ HB_SCRIPT_REJANG                      = HB_TAG ('R','j','n','g'),
244   /*5.1*/ HB_SCRIPT_SAURASHTRA                  = HB_TAG ('S','a','u','r'),
245   /*5.1*/ HB_SCRIPT_SUNDANESE                   = HB_TAG ('S','u','n','d'),
246   /*5.1*/ HB_SCRIPT_VAI                         = HB_TAG ('V','a','i','i'),
247
248   /*5.2*/ HB_SCRIPT_AVESTAN                     = HB_TAG ('A','v','s','t'),
249   /*5.2*/ HB_SCRIPT_BAMUM                       = HB_TAG ('B','a','m','u'),
250   /*5.2*/ HB_SCRIPT_EGYPTIAN_HIEROGLYPHS        = HB_TAG ('E','g','y','p'),
251   /*5.2*/ HB_SCRIPT_IMPERIAL_ARAMAIC            = HB_TAG ('A','r','m','i'),
252   /*5.2*/ HB_SCRIPT_INSCRIPTIONAL_PAHLAVI       = HB_TAG ('P','h','l','i'),
253   /*5.2*/ HB_SCRIPT_INSCRIPTIONAL_PARTHIAN      = HB_TAG ('P','r','t','i'),
254   /*5.2*/ HB_SCRIPT_JAVANESE                    = HB_TAG ('J','a','v','a'),
255   /*5.2*/ HB_SCRIPT_KAITHI                      = HB_TAG ('K','t','h','i'),
256   /*5.2*/ HB_SCRIPT_LISU                        = HB_TAG ('L','i','s','u'),
257   /*5.2*/ HB_SCRIPT_MEETEI_MAYEK                = HB_TAG ('M','t','e','i'),
258   /*5.2*/ HB_SCRIPT_OLD_SOUTH_ARABIAN           = HB_TAG ('S','a','r','b'),
259   /*5.2*/ HB_SCRIPT_OLD_TURKIC                  = HB_TAG ('O','r','k','h'),
260   /*5.2*/ HB_SCRIPT_SAMARITAN                   = HB_TAG ('S','a','m','r'),
261   /*5.2*/ HB_SCRIPT_TAI_THAM                    = HB_TAG ('L','a','n','a'),
262   /*5.2*/ HB_SCRIPT_TAI_VIET                    = HB_TAG ('T','a','v','t'),
263
264   /*6.0*/ HB_SCRIPT_BATAK                       = HB_TAG ('B','a','t','k'),
265   /*6.0*/ HB_SCRIPT_BRAHMI                      = HB_TAG ('B','r','a','h'),
266   /*6.0*/ HB_SCRIPT_MANDAIC                     = HB_TAG ('M','a','n','d'),
267
268   /*6.1*/ HB_SCRIPT_CHAKMA                      = HB_TAG ('C','a','k','m'),
269   /*6.1*/ HB_SCRIPT_MEROITIC_CURSIVE            = HB_TAG ('M','e','r','c'),
270   /*6.1*/ HB_SCRIPT_MEROITIC_HIEROGLYPHS        = HB_TAG ('M','e','r','o'),
271   /*6.1*/ HB_SCRIPT_MIAO                        = HB_TAG ('P','l','r','d'),
272   /*6.1*/ HB_SCRIPT_SHARADA                     = HB_TAG ('S','h','r','d'),
273   /*6.1*/ HB_SCRIPT_SORA_SOMPENG                = HB_TAG ('S','o','r','a'),
274   /*6.1*/ HB_SCRIPT_TAKRI                       = HB_TAG ('T','a','k','r'),
275
276   /*
277    * Since: 0.9.30
278    */
279   /*7.0*/ HB_SCRIPT_BASSA_VAH                   = HB_TAG ('B','a','s','s'),
280   /*7.0*/ HB_SCRIPT_CAUCASIAN_ALBANIAN          = HB_TAG ('A','g','h','b'),
281   /*7.0*/ HB_SCRIPT_DUPLOYAN                    = HB_TAG ('D','u','p','l'),
282   /*7.0*/ HB_SCRIPT_ELBASAN                     = HB_TAG ('E','l','b','a'),
283   /*7.0*/ HB_SCRIPT_GRANTHA                     = HB_TAG ('G','r','a','n'),
284   /*7.0*/ HB_SCRIPT_KHOJKI                      = HB_TAG ('K','h','o','j'),
285   /*7.0*/ HB_SCRIPT_KHUDAWADI                   = HB_TAG ('S','i','n','d'),
286   /*7.0*/ HB_SCRIPT_LINEAR_A                    = HB_TAG ('L','i','n','a'),
287   /*7.0*/ HB_SCRIPT_MAHAJANI                    = HB_TAG ('M','a','h','j'),
288   /*7.0*/ HB_SCRIPT_MANICHAEAN                  = HB_TAG ('M','a','n','i'),
289   /*7.0*/ HB_SCRIPT_MENDE_KIKAKUI               = HB_TAG ('M','e','n','d'),
290   /*7.0*/ HB_SCRIPT_MODI                        = HB_TAG ('M','o','d','i'),
291   /*7.0*/ HB_SCRIPT_MRO                         = HB_TAG ('M','r','o','o'),
292   /*7.0*/ HB_SCRIPT_NABATAEAN                   = HB_TAG ('N','b','a','t'),
293   /*7.0*/ HB_SCRIPT_OLD_NORTH_ARABIAN           = HB_TAG ('N','a','r','b'),
294   /*7.0*/ HB_SCRIPT_OLD_PERMIC                  = HB_TAG ('P','e','r','m'),
295   /*7.0*/ HB_SCRIPT_PAHAWH_HMONG                = HB_TAG ('H','m','n','g'),
296   /*7.0*/ HB_SCRIPT_PALMYRENE                   = HB_TAG ('P','a','l','m'),
297   /*7.0*/ HB_SCRIPT_PAU_CIN_HAU                 = HB_TAG ('P','a','u','c'),
298   /*7.0*/ HB_SCRIPT_PSALTER_PAHLAVI             = HB_TAG ('P','h','l','p'),
299   /*7.0*/ HB_SCRIPT_SIDDHAM                     = HB_TAG ('S','i','d','d'),
300   /*7.0*/ HB_SCRIPT_TIRHUTA                     = HB_TAG ('T','i','r','h'),
301   /*7.0*/ HB_SCRIPT_WARANG_CITI                 = HB_TAG ('W','a','r','a'),
302
303   /*8.0*/ HB_SCRIPT_AHOM                        = HB_TAG ('A','h','o','m'),
304   /*8.0*/ HB_SCRIPT_ANATOLIAN_HIEROGLYPHS       = HB_TAG ('H','l','u','w'),
305   /*8.0*/ HB_SCRIPT_HATRAN                      = HB_TAG ('H','a','t','r'),
306   /*8.0*/ HB_SCRIPT_MULTANI                     = HB_TAG ('M','u','l','t'),
307   /*8.0*/ HB_SCRIPT_OLD_HUNGARIAN               = HB_TAG ('H','u','n','g'),
308   /*8.0*/ HB_SCRIPT_SIGNWRITING                 = HB_TAG ('S','g','n','w'),
309
310   /*
311    * Since 1.3.0
312    */
313   /*9.0*/ HB_SCRIPT_ADLAM                       = HB_TAG ('A','d','l','m'),
314   /*9.0*/ HB_SCRIPT_BHAIKSUKI                   = HB_TAG ('B','h','k','s'),
315   /*9.0*/ HB_SCRIPT_MARCHEN                     = HB_TAG ('M','a','r','c'),
316   /*9.0*/ HB_SCRIPT_OSAGE                       = HB_TAG ('O','s','g','e'),
317   /*9.0*/ HB_SCRIPT_TANGUT                      = HB_TAG ('T','a','n','g'),
318   /*9.0*/ HB_SCRIPT_NEWA                        = HB_TAG ('N','e','w','a'),
319
320   /*
321    * Since 1.6.0
322    */
323   /*10.0*/HB_SCRIPT_MASARAM_GONDI               = HB_TAG ('G','o','n','m'),
324   /*10.0*/HB_SCRIPT_NUSHU                       = HB_TAG ('N','s','h','u'),
325   /*10.0*/HB_SCRIPT_SOYOMBO                     = HB_TAG ('S','o','y','o'),
326   /*10.0*/HB_SCRIPT_ZANABAZAR_SQUARE            = HB_TAG ('Z','a','n','b'),
327
328   /*
329    * Since 1.8.0
330    */
331   /*11.0*/HB_SCRIPT_DOGRA                       = HB_TAG ('D','o','g','r'),
332   /*11.0*/HB_SCRIPT_GUNJALA_GONDI               = HB_TAG ('G','o','n','g'),
333   /*11.0*/HB_SCRIPT_HANIFI_ROHINGYA             = HB_TAG ('R','o','h','g'),
334   /*11.0*/HB_SCRIPT_MAKASAR                     = HB_TAG ('M','a','k','a'),
335   /*11.0*/HB_SCRIPT_MEDEFAIDRIN                 = HB_TAG ('M','e','d','f'),
336   /*11.0*/HB_SCRIPT_OLD_SOGDIAN                 = HB_TAG ('S','o','g','o'),
337   /*11.0*/HB_SCRIPT_SOGDIAN                     = HB_TAG ('S','o','g','d'),
338
339   /* No script set. */
340   HB_SCRIPT_INVALID                             = HB_TAG_NONE,
341
342   /* Dummy values to ensure any hb_tag_t value can be passed/stored as hb_script_t
343    * without risking undefined behavior.  Include both a signed and unsigned max,
344    * since technically enums are int, and indeed, hb_script_t ends up being signed.
345    * See this thread for technicalities:
346    *
347    *   https://lists.freedesktop.org/archives/harfbuzz/2014-March/004150.html
348    */
349   _HB_SCRIPT_MAX_VALUE                          = HB_TAG_MAX, /*< skip >*/
350   _HB_SCRIPT_MAX_VALUE_SIGNED                   = HB_TAG_MAX_SIGNED /*< skip >*/
351
352 } hb_script_t;
353
354
355 /* Script functions */
356
357 HB_EXTERN hb_script_t
358 hb_script_from_iso15924_tag (hb_tag_t tag);
359
360 HB_EXTERN hb_script_t
361 hb_script_from_string (const char *str, int len);
362
363 HB_EXTERN hb_tag_t
364 hb_script_to_iso15924_tag (hb_script_t script);
365
366 HB_EXTERN hb_direction_t
367 hb_script_get_horizontal_direction (hb_script_t script);
368
369
370 /* User data */
371
372 typedef struct hb_user_data_key_t {
373   /*< private >*/
374   char unused;
375 } hb_user_data_key_t;
376
377 typedef void (*hb_destroy_func_t) (void *user_data);
378
379
380 /* Font features and variations. */
381
382 typedef struct hb_feature_t {
383   hb_tag_t      tag;
384   uint32_t      value;
385   unsigned int  start;
386   unsigned int  end;
387 } hb_feature_t;
388
389 HB_EXTERN hb_bool_t
390 hb_feature_from_string (const char *str, int len,
391                         hb_feature_t *feature);
392
393 HB_EXTERN void
394 hb_feature_to_string (hb_feature_t *feature,
395                       char *buf, unsigned int size);
396
397 /**
398  * hb_variation_t:
399  *
400  * Since: 1.4.2
401  */
402 typedef struct hb_variation_t {
403   hb_tag_t tag;
404   float    value;
405 } hb_variation_t;
406
407 HB_EXTERN hb_bool_t
408 hb_variation_from_string (const char *str, int len,
409                           hb_variation_t *variation);
410
411 HB_EXTERN void
412 hb_variation_to_string (hb_variation_t *variation,
413                         char *buf, unsigned int size);
414
415
416 HB_END_DECLS
417
418 #endif /* HB_COMMON_H */