src/hb-unicode-private.hh

/*
 * Copyright © 2009  Red Hat, Inc.
 * Copyright © 2011  Codethink Limited
 * Copyright © 2010,2011  Google, Inc.
 *
 *  This is part of HarfBuzz, a text shaping library.
 *
 * Permission is hereby granted, without written agreement and without
 * license or royalty fees, to use, copy, modify, and distribute this
 * software and its documentation for any purpose, provided that the
 * above copyright notice and the following two paragraphs appear in
 * all copies of this software.
 *
 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGE.
 *
 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
 * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
 *
 * Red Hat Author(s): Behdad Esfahbod
 * Codethink Author(s): Ryan Lortie
 * Google Author(s): Behdad Esfahbod
 */

#ifndef HB_UNICODE_PRIVATE_HH
#define HB_UNICODE_PRIVATE_HH

#include "hb-private.hh"

#include "hb-unicode.h"
#include "hb-object-private.hh"



/*
 * hb_unicode_funcs_t
 */

#define HB_UNICODE_FUNCS_IMPLEMENT_CALLBACKS \
  HB_UNICODE_FUNC_IMPLEMENT (combining_class) \
  HB_UNICODE_FUNC_IMPLEMENT (eastasian_width) \
  HB_UNICODE_FUNC_IMPLEMENT (general_category) \
  HB_UNICODE_FUNC_IMPLEMENT (mirroring) \
  HB_UNICODE_FUNC_IMPLEMENT (script) \
  HB_UNICODE_FUNC_IMPLEMENT (compose) \
  HB_UNICODE_FUNC_IMPLEMENT (decompose) \
  /* ^--- Add new callbacks here */

/* Simple callbacks are those taking a hb_codepoint_t and returning a hb_codepoint_t */
#define HB_UNICODE_FUNCS_IMPLEMENT_CALLBACKS_SIMPLE \
  HB_UNICODE_FUNC_IMPLEMENT (unsigned int, combining_class) \
  HB_UNICODE_FUNC_IMPLEMENT (unsigned int, eastasian_width) \
  HB_UNICODE_FUNC_IMPLEMENT (hb_unicode_general_category_t, general_category) \
  HB_UNICODE_FUNC_IMPLEMENT (hb_codepoint_t, mirroring) \
  HB_UNICODE_FUNC_IMPLEMENT (hb_script_t, script) \
  /* ^--- Add new simple callbacks here */

struct _hb_unicode_funcs_t {
  hb_object_header_t header;

  hb_unicode_funcs_t *parent;

  bool immutable;

  /* Don't access these directly.  Call hb_unicode_*() instead. */

  struct {
#define HB_UNICODE_FUNC_IMPLEMENT(name) hb_unicode_##name##_func_t name;
    HB_UNICODE_FUNCS_IMPLEMENT_CALLBACKS
#undef HB_UNICODE_FUNC_IMPLEMENT
  } func;

  struct {
#define HB_UNICODE_FUNC_IMPLEMENT(name) void *name;
    HB_UNICODE_FUNCS_IMPLEMENT_CALLBACKS
#undef HB_UNICODE_FUNC_IMPLEMENT
  } user_data;

  struct {
#define HB_UNICODE_FUNC_IMPLEMENT(name) hb_destroy_func_t name;
    HB_UNICODE_FUNCS_IMPLEMENT_CALLBACKS
#undef HB_UNICODE_FUNC_IMPLEMENT
  } destroy;
};


#ifdef HAVE_GLIB
extern HB_INTERNAL hb_unicode_funcs_t _hb_glib_unicode_funcs;
#define _hb_unicode_funcs_default _hb_glib_unicode_funcs
#elif defined(HAVE_ICU)
extern HB_INTERNAL hb_unicode_funcs_t _hb_icu_unicode_funcs;
#define _hb_unicode_funcs_default _hb_icu_unicode_funcs
#else
#define HB_UNICODE_FUNCS_NIL 1
extern HB_INTERNAL hb_unicode_funcs_t _hb_unicode_funcs_nil;
#define _hb_unicode_funcs_default _hb_unicode_funcs_nil
#endif


HB_INTERNAL unsigned int
_hb_unicode_modified_combining_class (hb_unicode_funcs_t *ufuncs,
				      hb_codepoint_t      unicode);

static inline hb_bool_t
_hb_unicode_is_variation_selector (hb_codepoint_t unicode)
{
  return unlikely ((unicode >=  0x180B && unicode <=  0x180D) || /* MONGOLIAN FREE VARIATION SELECTOR ONE..THREE */
		   (unicode >=  0xFE00 && unicode <=  0xFE0F) || /* VARIATION SELECTOR-1..16 */
		   (unicode >= 0xE0100 && unicode <= 0xE01EF));  /* VARIATION SELECTOR-17..256 */
}

/* Zero-Width invisible characters:
 *
 *  00AD  SOFT HYPHEN
 *  034F  COMBINING GRAPHEME JOINER
 *
 *  200B  ZERO WIDTH SPACE
 *  200C  ZERO WIDTH NON-JOINER
 *  200D  ZERO WIDTH JOINER
 *  200E  LEFT-TO-RIGHT MARK
 *  200F  RIGHT-TO-LEFT MARK
 *
 *  2028  LINE SEPARATOR
 *
 *  202A  LEFT-TO-RIGHT EMBEDDING
 *  202B  RIGHT-TO-LEFT EMBEDDING
 *  202C  POP DIRECTIONAL FORMATTING
 *  202D  LEFT-TO-RIGHT OVERRIDE
 *  202E  RIGHT-TO-LEFT OVERRIDE
 *
 *  2060  WORD JOINER
 *  2061  FUNCTION APPLICATION
 *  2062  INVISIBLE TIMES
 *  2063  INVISIBLE SEPARATOR
 *
 *  FEFF  ZERO WIDTH NO-BREAK SPACE
 */
static inline hb_bool_t
_hb_unicode_is_zero_width (hb_codepoint_t ch)
{
  return ((ch & ~0x007F) == 0x2000 && (
	  (ch >= 0x200B && ch <= 0x200F) ||
	  (ch >= 0x202A && ch <= 0x202E) ||
	  (ch >= 0x2060 && ch <= 0x2063) ||
	  (ch == 0x2028)
	 )) || unlikely (ch == 0x00AD
		      || ch == 0x034F
		      || ch == 0xFEFF);
}

#endif /* HB_UNICODE_PRIVATE_HH */