michael@0: /*
michael@0:  * Copyright © 2007,2008,2009,2010  Red Hat, Inc.
michael@0:  * Copyright © 2010,2012  Google, Inc.
michael@0:  *
michael@0:  *  This is part of HarfBuzz, a text shaping library.
michael@0:  *
michael@0:  * Permission is hereby granted, without written agreement and without
michael@0:  * license or royalty fees, to use, copy, modify, and distribute this
michael@0:  * software and its documentation for any purpose, provided that the
michael@0:  * above copyright notice and the following two paragraphs appear in
michael@0:  * all copies of this software.
michael@0:  *
michael@0:  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
michael@0:  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
michael@0:  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
michael@0:  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
michael@0:  * DAMAGE.
michael@0:  *
michael@0:  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
michael@0:  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
michael@0:  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
michael@0:  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
michael@0:  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
michael@0:  *
michael@0:  * Red Hat Author(s): Behdad Esfahbod
michael@0:  * Google Author(s): Behdad Esfahbod
michael@0:  */
michael@0: 
michael@0: #ifndef HB_OT_LAYOUT_GSUBGPOS_PRIVATE_HH
michael@0: #define HB_OT_LAYOUT_GSUBGPOS_PRIVATE_HH
michael@0: 
michael@0: #include "hb-buffer-private.hh"
michael@0: #include "hb-ot-layout-gdef-table.hh"
michael@0: #include "hb-set-private.hh"
michael@0: 
michael@0: 
michael@0: namespace OT {
michael@0: 
michael@0: 
michael@0: 
michael@0: #define TRACE_DISPATCH(this) \
michael@0: 	hb_auto_trace_t<context_t::max_debug_depth, typename context_t::return_t> trace \
michael@0: 	(&c->debug_depth, c->get_name (), this, HB_FUNC, \
michael@0: 	 "");
michael@0: 
michael@0: #ifndef HB_DEBUG_CLOSURE
michael@0: #define HB_DEBUG_CLOSURE (HB_DEBUG+0)
michael@0: #endif
michael@0: 
michael@0: #define TRACE_CLOSURE(this) \
michael@0: 	hb_auto_trace_t<HB_DEBUG_CLOSURE, hb_void_t> trace \
michael@0: 	(&c->debug_depth, c->get_name (), this, HB_FUNC, \
michael@0: 	 "");
michael@0: 
michael@0: struct hb_closure_context_t
michael@0: {
michael@0:   inline const char *get_name (void) { return "CLOSURE"; }
michael@0:   static const unsigned int max_debug_depth = HB_DEBUG_CLOSURE;
michael@0:   typedef hb_void_t return_t;
michael@0:   typedef return_t (*recurse_func_t) (hb_closure_context_t *c, unsigned int lookup_index);
michael@0:   template <typename T>
michael@0:   inline return_t dispatch (const T &obj) { obj.closure (this); return HB_VOID; }
michael@0:   static return_t default_return_value (void) { return HB_VOID; }
michael@0:   bool stop_sublookup_iteration (return_t r HB_UNUSED) const { return false; }
michael@0:   return_t recurse (unsigned int lookup_index)
michael@0:   {
michael@0:     if (unlikely (nesting_level_left == 0 || !recurse_func))
michael@0:       return default_return_value ();
michael@0: 
michael@0:     nesting_level_left--;
michael@0:     recurse_func (this, lookup_index);
michael@0:     nesting_level_left++;
michael@0:     return HB_VOID;
michael@0:   }
michael@0: 
michael@0:   hb_face_t *face;
michael@0:   hb_set_t *glyphs;
michael@0:   recurse_func_t recurse_func;
michael@0:   unsigned int nesting_level_left;
michael@0:   unsigned int debug_depth;
michael@0: 
michael@0:   hb_closure_context_t (hb_face_t *face_,
michael@0: 			hb_set_t *glyphs_,
michael@0: 		        unsigned int nesting_level_left_ = MAX_NESTING_LEVEL) :
michael@0: 			  face (face_),
michael@0: 			  glyphs (glyphs_),
michael@0: 			  recurse_func (NULL),
michael@0: 			  nesting_level_left (nesting_level_left_),
michael@0: 			  debug_depth (0) {}
michael@0: 
michael@0:   void set_recurse_func (recurse_func_t func) { recurse_func = func; }
michael@0: };
michael@0: 
michael@0: 
michael@0: 
michael@0: #ifndef HB_DEBUG_WOULD_APPLY
michael@0: #define HB_DEBUG_WOULD_APPLY (HB_DEBUG+0)
michael@0: #endif
michael@0: 
michael@0: #define TRACE_WOULD_APPLY(this) \
michael@0: 	hb_auto_trace_t<HB_DEBUG_WOULD_APPLY, bool> trace \
michael@0: 	(&c->debug_depth, c->get_name (), this, HB_FUNC, \
michael@0: 	 "%d glyphs", c->len);
michael@0: 
michael@0: struct hb_would_apply_context_t
michael@0: {
michael@0:   inline const char *get_name (void) { return "WOULD_APPLY"; }
michael@0:   static const unsigned int max_debug_depth = HB_DEBUG_WOULD_APPLY;
michael@0:   typedef bool return_t;
michael@0:   template <typename T>
michael@0:   inline return_t dispatch (const T &obj) { return obj.would_apply (this); }
michael@0:   static return_t default_return_value (void) { return false; }
michael@0:   bool stop_sublookup_iteration (return_t r) const { return r; }
michael@0: 
michael@0:   hb_face_t *face;
michael@0:   const hb_codepoint_t *glyphs;
michael@0:   unsigned int len;
michael@0:   bool zero_context;
michael@0:   unsigned int debug_depth;
michael@0: 
michael@0:   hb_would_apply_context_t (hb_face_t *face_,
michael@0: 			    const hb_codepoint_t *glyphs_,
michael@0: 			    unsigned int len_,
michael@0: 			    bool zero_context_) :
michael@0: 			      face (face_),
michael@0: 			      glyphs (glyphs_),
michael@0: 			      len (len_),
michael@0: 			      zero_context (zero_context_),
michael@0: 			      debug_depth (0) {}
michael@0: };
michael@0: 
michael@0: 
michael@0: 
michael@0: #ifndef HB_DEBUG_COLLECT_GLYPHS
michael@0: #define HB_DEBUG_COLLECT_GLYPHS (HB_DEBUG+0)
michael@0: #endif
michael@0: 
michael@0: #define TRACE_COLLECT_GLYPHS(this) \
michael@0: 	hb_auto_trace_t<HB_DEBUG_COLLECT_GLYPHS, hb_void_t> trace \
michael@0: 	(&c->debug_depth, c->get_name (), this, HB_FUNC, \
michael@0: 	 "");
michael@0: 
michael@0: struct hb_collect_glyphs_context_t
michael@0: {
michael@0:   inline const char *get_name (void) { return "COLLECT_GLYPHS"; }
michael@0:   static const unsigned int max_debug_depth = HB_DEBUG_COLLECT_GLYPHS;
michael@0:   typedef hb_void_t return_t;
michael@0:   typedef return_t (*recurse_func_t) (hb_collect_glyphs_context_t *c, unsigned int lookup_index);
michael@0:   template <typename T>
michael@0:   inline return_t dispatch (const T &obj) { obj.collect_glyphs (this); return HB_VOID; }
michael@0:   static return_t default_return_value (void) { return HB_VOID; }
michael@0:   bool stop_sublookup_iteration (return_t r HB_UNUSED) const { return false; }
michael@0:   return_t recurse (unsigned int lookup_index)
michael@0:   {
michael@0:     if (unlikely (nesting_level_left == 0 || !recurse_func))
michael@0:       return default_return_value ();
michael@0: 
michael@0:     /* Note that GPOS sets recurse_func to NULL already, so it doesn't get
michael@0:      * past the previous check.  For GSUB, we only want to collect the output
michael@0:      * glyphs in the recursion.  If output is not requested, we can go home now.
michael@0:      *
michael@0:      * Note further, that the above is not exactly correct.  A recursed lookup
michael@0:      * is allowed to match input that is not matched in the context, but that's
michael@0:      * not how most fonts are built.  It's possible to relax that and recurse
michael@0:      * with all sets here if it proves to be an issue.
michael@0:      */
michael@0: 
michael@0:     if (output == hb_set_get_empty ())
michael@0:       return HB_VOID;
michael@0: 
michael@0:     hb_set_t *old_before = before;
michael@0:     hb_set_t *old_input  = input;
michael@0:     hb_set_t *old_after  = after;
michael@0:     before = input = after = hb_set_get_empty ();
michael@0: 
michael@0:     nesting_level_left--;
michael@0:     recurse_func (this, lookup_index);
michael@0:     nesting_level_left++;
michael@0: 
michael@0:     before = old_before;
michael@0:     input  = old_input;
michael@0:     after  = old_after;
michael@0: 
michael@0:     return HB_VOID;
michael@0:   }
michael@0: 
michael@0:   hb_face_t *face;
michael@0:   hb_set_t *before;
michael@0:   hb_set_t *input;
michael@0:   hb_set_t *after;
michael@0:   hb_set_t *output;
michael@0:   recurse_func_t recurse_func;
michael@0:   unsigned int nesting_level_left;
michael@0:   unsigned int debug_depth;
michael@0: 
michael@0:   hb_collect_glyphs_context_t (hb_face_t *face_,
michael@0: 			       hb_set_t  *glyphs_before, /* OUT. May be NULL */
michael@0: 			       hb_set_t  *glyphs_input,  /* OUT. May be NULL */
michael@0: 			       hb_set_t  *glyphs_after,  /* OUT. May be NULL */
michael@0: 			       hb_set_t  *glyphs_output, /* OUT. May be NULL */
michael@0: 			       unsigned int nesting_level_left_ = MAX_NESTING_LEVEL) :
michael@0: 			      face (face_),
michael@0: 			      before (glyphs_before ? glyphs_before : hb_set_get_empty ()),
michael@0: 			      input  (glyphs_input  ? glyphs_input  : hb_set_get_empty ()),
michael@0: 			      after  (glyphs_after  ? glyphs_after  : hb_set_get_empty ()),
michael@0: 			      output (glyphs_output ? glyphs_output : hb_set_get_empty ()),
michael@0: 			      recurse_func (NULL),
michael@0: 			      nesting_level_left (nesting_level_left_),
michael@0: 			      debug_depth (0) {}
michael@0: 
michael@0:   void set_recurse_func (recurse_func_t func) { recurse_func = func; }
michael@0: };
michael@0: 
michael@0: 
michael@0: 
michael@0: struct hb_get_coverage_context_t
michael@0: {
michael@0:   inline const char *get_name (void) { return "GET_COVERAGE"; }
michael@0:   static const unsigned int max_debug_depth = 0;
michael@0:   typedef const Coverage &return_t;
michael@0:   template <typename T>
michael@0:   inline return_t dispatch (const T &obj) { return obj.get_coverage (); }
michael@0:   static return_t default_return_value (void) { return Null(Coverage); }
michael@0: 
michael@0:   hb_get_coverage_context_t (void) :
michael@0: 			    debug_depth (0) {}
michael@0: 
michael@0:   unsigned int debug_depth;
michael@0: };
michael@0: 
michael@0: 
michael@0: 
michael@0: #ifndef HB_DEBUG_APPLY
michael@0: #define HB_DEBUG_APPLY (HB_DEBUG+0)
michael@0: #endif
michael@0: 
michael@0: #define TRACE_APPLY(this) \
michael@0: 	hb_auto_trace_t<HB_DEBUG_APPLY, bool> trace \
michael@0: 	(&c->debug_depth, c->get_name (), this, HB_FUNC, \
michael@0: 	 "idx %d codepoint %u", c->buffer->idx, c->buffer->cur().codepoint);
michael@0: 
michael@0: struct hb_apply_context_t
michael@0: {
michael@0:   inline const char *get_name (void) { return "APPLY"; }
michael@0:   static const unsigned int max_debug_depth = HB_DEBUG_APPLY;
michael@0:   typedef bool return_t;
michael@0:   typedef return_t (*recurse_func_t) (hb_apply_context_t *c, unsigned int lookup_index);
michael@0:   template <typename T>
michael@0:   inline return_t dispatch (const T &obj) { return obj.apply (this); }
michael@0:   static return_t default_return_value (void) { return false; }
michael@0:   bool stop_sublookup_iteration (return_t r) const { return r; }
michael@0:   return_t recurse (unsigned int lookup_index)
michael@0:   {
michael@0:     if (unlikely (nesting_level_left == 0 || !recurse_func))
michael@0:       return default_return_value ();
michael@0: 
michael@0:     nesting_level_left--;
michael@0:     bool ret = recurse_func (this, lookup_index);
michael@0:     nesting_level_left++;
michael@0:     return ret;
michael@0:   }
michael@0: 
michael@0:   unsigned int table_index; /* GSUB/GPOS */
michael@0:   hb_font_t *font;
michael@0:   hb_face_t *face;
michael@0:   hb_buffer_t *buffer;
michael@0:   hb_direction_t direction;
michael@0:   hb_mask_t lookup_mask;
michael@0:   bool auto_zwj;
michael@0:   recurse_func_t recurse_func;
michael@0:   unsigned int nesting_level_left;
michael@0:   unsigned int lookup_props;
michael@0:   const GDEF &gdef;
michael@0:   bool has_glyph_classes;
michael@0:   unsigned int debug_depth;
michael@0: 
michael@0: 
michael@0:   hb_apply_context_t (unsigned int table_index_,
michael@0: 		      hb_font_t *font_,
michael@0: 		      hb_buffer_t *buffer_) :
michael@0: 			table_index (table_index_),
michael@0: 			font (font_), face (font->face), buffer (buffer_),
michael@0: 			direction (buffer_->props.direction),
michael@0: 			lookup_mask (1),
michael@0: 			auto_zwj (true),
michael@0: 			recurse_func (NULL),
michael@0: 			nesting_level_left (MAX_NESTING_LEVEL),
michael@0: 			lookup_props (0),
michael@0: 			gdef (*hb_ot_layout_from_face (face)->gdef),
michael@0: 			has_glyph_classes (gdef.has_glyph_classes ()),
michael@0: 			debug_depth (0) {}
michael@0: 
michael@0:   inline void set_lookup_mask (hb_mask_t mask) { lookup_mask = mask; }
michael@0:   inline void set_auto_zwj (bool auto_zwj_) { auto_zwj = auto_zwj_; }
michael@0:   inline void set_recurse_func (recurse_func_t func) { recurse_func = func; }
michael@0:   inline void set_lookup_props (unsigned int lookup_props_) { lookup_props = lookup_props_; }
michael@0:   inline void set_lookup (const Lookup &l) { lookup_props = l.get_props (); }
michael@0: 
michael@0:   struct matcher_t
michael@0:   {
michael@0:     inline matcher_t (void) :
michael@0: 	     lookup_props (0),
michael@0: 	     ignore_zwnj (false),
michael@0: 	     ignore_zwj (false),
michael@0: 	     mask (-1),
michael@0: #define arg1(arg) (arg) /* Remove the macro to see why it's needed! */
michael@0: 	     syllable arg1(0),
michael@0: #undef arg1
michael@0: 	     match_func (NULL),
michael@0: 	     match_data (NULL) {};
michael@0: 
michael@0:     typedef bool (*match_func_t) (hb_codepoint_t glyph_id, const USHORT &value, const void *data);
michael@0: 
michael@0:     inline void set_ignore_zwnj (bool ignore_zwnj_) { ignore_zwnj = ignore_zwnj_; }
michael@0:     inline void set_ignore_zwj (bool ignore_zwj_) { ignore_zwj = ignore_zwj_; }
michael@0:     inline void set_lookup_props (unsigned int lookup_props_) { lookup_props = lookup_props_; }
michael@0:     inline void set_mask (hb_mask_t mask_) { mask = mask_; }
michael@0:     inline void set_syllable (uint8_t syllable_)  { syllable = syllable_; }
michael@0:     inline void set_match_func (match_func_t match_func_,
michael@0: 				const void *match_data_)
michael@0:     { match_func = match_func_; match_data = match_data_; }
michael@0: 
michael@0:     enum may_match_t {
michael@0:       MATCH_NO,
michael@0:       MATCH_YES,
michael@0:       MATCH_MAYBE
michael@0:     };
michael@0: 
michael@0:     inline may_match_t may_match (const hb_glyph_info_t &info,
michael@0: 				  const USHORT          *glyph_data) const
michael@0:     {
michael@0:       if (!(info.mask & mask) ||
michael@0: 	  (syllable && syllable != info.syllable ()))
michael@0: 	return MATCH_NO;
michael@0: 
michael@0:       if (match_func)
michael@0:         return match_func (info.codepoint, *glyph_data, match_data) ? MATCH_YES : MATCH_NO;
michael@0: 
michael@0:       return MATCH_MAYBE;
michael@0:     }
michael@0: 
michael@0:     enum may_skip_t {
michael@0:       SKIP_NO,
michael@0:       SKIP_YES,
michael@0:       SKIP_MAYBE
michael@0:     };
michael@0: 
michael@0:     inline may_skip_t
michael@0:     may_skip (const hb_apply_context_t *c,
michael@0: 	      const hb_glyph_info_t    &info) const
michael@0:     {
michael@0:       unsigned int property;
michael@0: 
michael@0:       property = _hb_glyph_info_get_glyph_props (&info);
michael@0: 
michael@0:       if (!c->match_properties (info.codepoint, property, lookup_props))
michael@0: 	return SKIP_YES;
michael@0: 
michael@0:       if (unlikely (_hb_glyph_info_is_default_ignorable (&info) &&
michael@0: 		    (ignore_zwnj || !_hb_glyph_info_is_zwnj (&info)) &&
michael@0: 		    (ignore_zwj || !_hb_glyph_info_is_zwj (&info)) &&
michael@0: 		    !_hb_glyph_info_ligated (&info)))
michael@0: 	return SKIP_MAYBE;
michael@0: 
michael@0:       return SKIP_NO;
michael@0:     }
michael@0: 
michael@0:     protected:
michael@0:     unsigned int lookup_props;
michael@0:     bool ignore_zwnj;
michael@0:     bool ignore_zwj;
michael@0:     hb_mask_t mask;
michael@0:     uint8_t syllable;
michael@0:     match_func_t match_func;
michael@0:     const void *match_data;
michael@0:   };
michael@0: 
michael@0:   struct skipping_forward_iterator_t
michael@0:   {
michael@0:     inline skipping_forward_iterator_t (hb_apply_context_t *c_,
michael@0: 					unsigned int start_index_,
michael@0: 					unsigned int num_items_,
michael@0: 					bool context_match = false) :
michael@0: 					 idx (start_index_),
michael@0: 					 c (c_),
michael@0: 					 match_glyph_data (NULL),
michael@0: 					 num_items (num_items_),
michael@0: 					 end (c->buffer->len)
michael@0:     {
michael@0:       matcher.set_lookup_props (c->lookup_props);
michael@0:       /* Ignore ZWNJ if we are matching GSUB context, or matching GPOS. */
michael@0:       matcher.set_ignore_zwnj (context_match || c->table_index == 1);
michael@0:       /* Ignore ZWJ if we are matching GSUB context, or matching GPOS, or if asked to. */
michael@0:       matcher.set_ignore_zwj (context_match || c->table_index == 1 || c->auto_zwj);
michael@0:       if (!context_match)
michael@0: 	matcher.set_mask (c->lookup_mask);
michael@0:       matcher.set_syllable (start_index_ == c->buffer->idx ? c->buffer->cur().syllable () : 0);
michael@0:     }
michael@0:     inline void set_lookup_props (unsigned int lookup_props) { matcher.set_lookup_props (lookup_props); }
michael@0:     inline void set_syllable (unsigned int syllable) { matcher.set_syllable (syllable); }
michael@0:     inline void set_match_func (matcher_t::match_func_t match_func,
michael@0: 				const void *match_data,
michael@0: 				const USHORT glyph_data[])
michael@0:     {
michael@0:       matcher.set_match_func (match_func, match_data);
michael@0:       match_glyph_data = glyph_data;
michael@0:     }
michael@0: 
michael@0:     inline bool has_no_chance (void) const { return unlikely (num_items && idx + num_items >= end); }
michael@0:     inline void reject (void) { num_items++; match_glyph_data--; }
michael@0:     inline bool next (void)
michael@0:     {
michael@0:       assert (num_items > 0);
michael@0:       while (!has_no_chance ())
michael@0:       {
michael@0: 	idx++;
michael@0: 	const hb_glyph_info_t &info = c->buffer->info[idx];
michael@0: 
michael@0: 	matcher_t::may_skip_t skip = matcher.may_skip (c, info);
michael@0: 	if (unlikely (skip == matcher_t::SKIP_YES))
michael@0: 	  continue;
michael@0: 
michael@0: 	matcher_t::may_match_t match = matcher.may_match (info, match_glyph_data);
michael@0: 	if (match == matcher_t::MATCH_YES ||
michael@0: 	    (match == matcher_t::MATCH_MAYBE &&
michael@0: 	     skip == matcher_t::SKIP_NO))
michael@0: 	{
michael@0: 	  num_items--;
michael@0: 	  match_glyph_data++;
michael@0: 	  return true;
michael@0: 	}
michael@0: 
michael@0: 	if (skip == matcher_t::SKIP_NO)
michael@0: 	  return false;
michael@0:       }
michael@0:       return false;
michael@0:     }
michael@0: 
michael@0:     unsigned int idx;
michael@0:     protected:
michael@0:     hb_apply_context_t *c;
michael@0:     matcher_t matcher;
michael@0:     const USHORT *match_glyph_data;
michael@0: 
michael@0:     unsigned int num_items;
michael@0:     unsigned int end;
michael@0:   };
michael@0: 
michael@0:   struct skipping_backward_iterator_t
michael@0:   {
michael@0:     inline skipping_backward_iterator_t (hb_apply_context_t *c_,
michael@0: 					 unsigned int start_index_,
michael@0: 					 unsigned int num_items_,
michael@0: 					 bool context_match = false) :
michael@0: 					  idx (start_index_),
michael@0: 					  c (c_),
michael@0: 					  match_glyph_data (NULL),
michael@0: 					  num_items (num_items_)
michael@0:     {
michael@0:       matcher.set_lookup_props (c->lookup_props);
michael@0:       /* Ignore ZWNJ if we are matching GSUB context, or matching GPOS. */
michael@0:       matcher.set_ignore_zwnj (context_match || c->table_index == 1);
michael@0:       /* Ignore ZWJ if we are matching GSUB context, or matching GPOS, or if asked to. */
michael@0:       matcher.set_ignore_zwj (context_match || c->table_index == 1 || c->auto_zwj);
michael@0:       if (!context_match)
michael@0: 	matcher.set_mask (c->lookup_mask);
michael@0:       matcher.set_syllable (start_index_ == c->buffer->idx ? c->buffer->cur().syllable () : 0);
michael@0:     }
michael@0:     inline void set_lookup_props (unsigned int lookup_props) { matcher.set_lookup_props (lookup_props); }
michael@0:     inline void set_syllable (unsigned int syllable) { matcher.set_syllable (syllable); }
michael@0:     inline void set_match_func (matcher_t::match_func_t match_func,
michael@0: 				const void *match_data,
michael@0: 				const USHORT glyph_data[])
michael@0:     {
michael@0:       matcher.set_match_func (match_func, match_data);
michael@0:       match_glyph_data = glyph_data;
michael@0:     }
michael@0: 
michael@0:     inline bool has_no_chance (void) const { return unlikely (idx < num_items); }
michael@0:     inline void reject (void) { num_items++; }
michael@0:     inline bool prev (void)
michael@0:     {
michael@0:       assert (num_items > 0);
michael@0:       while (!has_no_chance ())
michael@0:       {
michael@0: 	idx--;
michael@0: 	const hb_glyph_info_t &info = c->buffer->out_info[idx];
michael@0: 
michael@0: 	matcher_t::may_skip_t skip = matcher.may_skip (c, info);
michael@0: 
michael@0: 	if (unlikely (skip == matcher_t::SKIP_YES))
michael@0: 	  continue;
michael@0: 
michael@0: 	matcher_t::may_match_t match = matcher.may_match (info, match_glyph_data);
michael@0: 	if (match == matcher_t::MATCH_YES ||
michael@0: 	    (match == matcher_t::MATCH_MAYBE &&
michael@0: 	     skip == matcher_t::SKIP_NO))
michael@0: 	{
michael@0: 	  num_items--;
michael@0: 	  match_glyph_data++;
michael@0: 	  return true;
michael@0: 	}
michael@0: 
michael@0: 	if (skip == matcher_t::SKIP_NO)
michael@0: 	  return false;
michael@0:       }
michael@0:       return false;
michael@0:     }
michael@0: 
michael@0:     unsigned int idx;
michael@0:     protected:
michael@0:     hb_apply_context_t *c;
michael@0:     matcher_t matcher;
michael@0:     const USHORT *match_glyph_data;
michael@0: 
michael@0:     unsigned int num_items;
michael@0:   };
michael@0: 
michael@0:   inline bool
michael@0:   match_properties_mark (hb_codepoint_t  glyph,
michael@0: 			 unsigned int    glyph_props,
michael@0: 			 unsigned int    lookup_props) const
michael@0:   {
michael@0:     /* If using mark filtering sets, the high short of
michael@0:      * lookup_props has the set index.
michael@0:      */
michael@0:     if (lookup_props & LookupFlag::UseMarkFilteringSet)
michael@0:       return gdef.mark_set_covers (lookup_props >> 16, glyph);
michael@0: 
michael@0:     /* The second byte of lookup_props has the meaning
michael@0:      * "ignore marks of attachment type different than
michael@0:      * the attachment type specified."
michael@0:      */
michael@0:     if (lookup_props & LookupFlag::MarkAttachmentType)
michael@0:       return (lookup_props & LookupFlag::MarkAttachmentType) == (glyph_props & LookupFlag::MarkAttachmentType);
michael@0: 
michael@0:     return true;
michael@0:   }
michael@0: 
michael@0:   inline bool
michael@0:   match_properties (hb_codepoint_t  glyph,
michael@0: 		    unsigned int    glyph_props,
michael@0: 		    unsigned int    lookup_props) const
michael@0:   {
michael@0:     /* Not covered, if, for example, glyph class is ligature and
michael@0:      * lookup_props includes LookupFlags::IgnoreLigatures
michael@0:      */
michael@0:     if (glyph_props & lookup_props & LookupFlag::IgnoreFlags)
michael@0:       return false;
michael@0: 
michael@0:     if (unlikely (glyph_props & HB_OT_LAYOUT_GLYPH_PROPS_MARK))
michael@0:       return match_properties_mark (glyph, glyph_props, lookup_props);
michael@0: 
michael@0:     return true;
michael@0:   }
michael@0: 
michael@0:   inline bool
michael@0:   check_glyph_property (hb_glyph_info_t *info,
michael@0: 			unsigned int  lookup_props) const
michael@0:   {
michael@0:     unsigned int property;
michael@0: 
michael@0:     property = _hb_glyph_info_get_glyph_props (info);
michael@0: 
michael@0:     return match_properties (info->codepoint, property, lookup_props);
michael@0:   }
michael@0: 
michael@0:   inline void _set_glyph_props (hb_codepoint_t glyph_index,
michael@0: 			  unsigned int class_guess = 0,
michael@0: 			  bool ligature = false) const
michael@0:   {
michael@0:     unsigned int add_in = _hb_glyph_info_get_glyph_props (&buffer->cur()) &
michael@0: 			  HB_OT_LAYOUT_GLYPH_PROPS_PRESERVE;
michael@0:     add_in |= HB_OT_LAYOUT_GLYPH_PROPS_SUBSTITUTED;
michael@0:     if (ligature)
michael@0:       add_in |= HB_OT_LAYOUT_GLYPH_PROPS_LIGATED;
michael@0:     if (likely (has_glyph_classes))
michael@0:       _hb_glyph_info_set_glyph_props (&buffer->cur(), add_in | gdef.get_glyph_props (glyph_index));
michael@0:     else if (class_guess)
michael@0:       _hb_glyph_info_set_glyph_props (&buffer->cur(), add_in | class_guess);
michael@0:   }
michael@0: 
michael@0:   inline void replace_glyph (hb_codepoint_t glyph_index) const
michael@0:   {
michael@0:     _set_glyph_props (glyph_index);
michael@0:     buffer->replace_glyph (glyph_index);
michael@0:   }
michael@0:   inline void replace_glyph_inplace (hb_codepoint_t glyph_index) const
michael@0:   {
michael@0:     _set_glyph_props (glyph_index);
michael@0:     buffer->cur().codepoint = glyph_index;
michael@0:   }
michael@0:   inline void replace_glyph_with_ligature (hb_codepoint_t glyph_index,
michael@0: 					   unsigned int class_guess) const
michael@0:   {
michael@0:     _set_glyph_props (glyph_index, class_guess, true);
michael@0:     buffer->replace_glyph (glyph_index);
michael@0:   }
michael@0:   inline void output_glyph (hb_codepoint_t glyph_index,
michael@0: 			    unsigned int class_guess) const
michael@0:   {
michael@0:     _set_glyph_props (glyph_index, class_guess);
michael@0:     buffer->output_glyph (glyph_index);
michael@0:   }
michael@0: };
michael@0: 
michael@0: 
michael@0: 
michael@0: typedef bool (*intersects_func_t) (hb_set_t *glyphs, const USHORT &value, const void *data);
michael@0: typedef void (*collect_glyphs_func_t) (hb_set_t *glyphs, const USHORT &value, const void *data);
michael@0: typedef bool (*match_func_t) (hb_codepoint_t glyph_id, const USHORT &value, const void *data);
michael@0: 
michael@0: struct ContextClosureFuncs
michael@0: {
michael@0:   intersects_func_t intersects;
michael@0: };
michael@0: struct ContextCollectGlyphsFuncs
michael@0: {
michael@0:   collect_glyphs_func_t collect;
michael@0: };
michael@0: struct ContextApplyFuncs
michael@0: {
michael@0:   match_func_t match;
michael@0: };
michael@0: 
michael@0: 
michael@0: static inline bool intersects_glyph (hb_set_t *glyphs, const USHORT &value, const void *data HB_UNUSED)
michael@0: {
michael@0:   return glyphs->has (value);
michael@0: }
michael@0: static inline bool intersects_class (hb_set_t *glyphs, const USHORT &value, const void *data)
michael@0: {
michael@0:   const ClassDef &class_def = *reinterpret_cast<const ClassDef *>(data);
michael@0:   return class_def.intersects_class (glyphs, value);
michael@0: }
michael@0: static inline bool intersects_coverage (hb_set_t *glyphs, const USHORT &value, const void *data)
michael@0: {
michael@0:   const OffsetTo<Coverage> &coverage = (const OffsetTo<Coverage>&)value;
michael@0:   return (data+coverage).intersects (glyphs);
michael@0: }
michael@0: 
michael@0: static inline bool intersects_array (hb_closure_context_t *c,
michael@0: 				     unsigned int count,
michael@0: 				     const USHORT values[],
michael@0: 				     intersects_func_t intersects_func,
michael@0: 				     const void *intersects_data)
michael@0: {
michael@0:   for (unsigned int i = 0; i < count; i++)
michael@0:     if (likely (!intersects_func (c->glyphs, values[i], intersects_data)))
michael@0:       return false;
michael@0:   return true;
michael@0: }
michael@0: 
michael@0: 
michael@0: static inline void collect_glyph (hb_set_t *glyphs, const USHORT &value, const void *data HB_UNUSED)
michael@0: {
michael@0:   glyphs->add (value);
michael@0: }
michael@0: static inline void collect_class (hb_set_t *glyphs, const USHORT &value, const void *data)
michael@0: {
michael@0:   const ClassDef &class_def = *reinterpret_cast<const ClassDef *>(data);
michael@0:   class_def.add_class (glyphs, value);
michael@0: }
michael@0: static inline void collect_coverage (hb_set_t *glyphs, const USHORT &value, const void *data)
michael@0: {
michael@0:   const OffsetTo<Coverage> &coverage = (const OffsetTo<Coverage>&)value;
michael@0:   (data+coverage).add_coverage (glyphs);
michael@0: }
michael@0: static inline void collect_array (hb_collect_glyphs_context_t *c HB_UNUSED,
michael@0: 				  hb_set_t *glyphs,
michael@0: 				  unsigned int count,
michael@0: 				  const USHORT values[],
michael@0: 				  collect_glyphs_func_t collect_func,
michael@0: 				  const void *collect_data)
michael@0: {
michael@0:   for (unsigned int i = 0; i < count; i++)
michael@0:     collect_func (glyphs, values[i], collect_data);
michael@0: }
michael@0: 
michael@0: 
michael@0: static inline bool match_glyph (hb_codepoint_t glyph_id, const USHORT &value, const void *data HB_UNUSED)
michael@0: {
michael@0:   return glyph_id == value;
michael@0: }
michael@0: static inline bool match_class (hb_codepoint_t glyph_id, const USHORT &value, const void *data)
michael@0: {
michael@0:   const ClassDef &class_def = *reinterpret_cast<const ClassDef *>(data);
michael@0:   return class_def.get_class (glyph_id) == value;
michael@0: }
michael@0: static inline bool match_coverage (hb_codepoint_t glyph_id, const USHORT &value, const void *data)
michael@0: {
michael@0:   const OffsetTo<Coverage> &coverage = (const OffsetTo<Coverage>&)value;
michael@0:   return (data+coverage).get_coverage (glyph_id) != NOT_COVERED;
michael@0: }
michael@0: 
michael@0: static inline bool would_match_input (hb_would_apply_context_t *c,
michael@0: 				      unsigned int count, /* Including the first glyph (not matched) */
michael@0: 				      const USHORT input[], /* Array of input values--start with second glyph */
michael@0: 				      match_func_t match_func,
michael@0: 				      const void *match_data)
michael@0: {
michael@0:   if (count != c->len)
michael@0:     return false;
michael@0: 
michael@0:   for (unsigned int i = 1; i < count; i++)
michael@0:     if (likely (!match_func (c->glyphs[i], input[i - 1], match_data)))
michael@0:       return false;
michael@0: 
michael@0:   return true;
michael@0: }
michael@0: static inline bool match_input (hb_apply_context_t *c,
michael@0: 				unsigned int count, /* Including the first glyph (not matched) */
michael@0: 				const USHORT input[], /* Array of input values--start with second glyph */
michael@0: 				match_func_t match_func,
michael@0: 				const void *match_data,
michael@0: 				unsigned int *end_offset,
michael@0: 				unsigned int match_positions[MAX_CONTEXT_LENGTH],
michael@0: 				bool *p_is_mark_ligature = NULL,
michael@0: 				unsigned int *p_total_component_count = NULL)
michael@0: {
michael@0:   TRACE_APPLY (NULL);
michael@0: 
michael@0:   if (unlikely (count > MAX_CONTEXT_LENGTH)) TRACE_RETURN (false);
michael@0: 
michael@0:   hb_buffer_t *buffer = c->buffer;
michael@0: 
michael@0:   hb_apply_context_t::skipping_forward_iterator_t skippy_iter (c, buffer->idx, count - 1);
michael@0:   skippy_iter.set_match_func (match_func, match_data, input);
michael@0:   if (skippy_iter.has_no_chance ()) return TRACE_RETURN (false);
michael@0: 
michael@0:   /*
michael@0:    * This is perhaps the trickiest part of OpenType...  Remarks:
michael@0:    *
michael@0:    * - If all components of the ligature were marks, we call this a mark ligature.
michael@0:    *
michael@0:    * - If there is no GDEF, and the ligature is NOT a mark ligature, we categorize
michael@0:    *   it as a ligature glyph.
michael@0:    *
michael@0:    * - Ligatures cannot be formed across glyphs attached to different components
michael@0:    *   of previous ligatures.  Eg. the sequence is LAM,SHADDA,LAM,FATHA,HEH, and
michael@0:    *   LAM,LAM,HEH form a ligature, leaving SHADDA,FATHA next to eachother.
michael@0:    *   However, it would be wrong to ligate that SHADDA,FATHA sequence.o
michael@0:    *   There is an exception to this: If a ligature tries ligating with marks that
michael@0:    *   belong to it itself, go ahead, assuming that the font designer knows what
michael@0:    *   they are doing (otherwise it can break Indic stuff when a matra wants to
michael@0:    *   ligate with a conjunct...)
michael@0:    */
michael@0: 
michael@0:   bool is_mark_ligature = _hb_glyph_info_is_mark (&buffer->cur());
michael@0: 
michael@0:   unsigned int total_component_count = 0;
michael@0:   total_component_count += _hb_glyph_info_get_lig_num_comps (&buffer->cur());
michael@0: 
michael@0:   unsigned int first_lig_id = _hb_glyph_info_get_lig_id (&buffer->cur());
michael@0:   unsigned int first_lig_comp = _hb_glyph_info_get_lig_comp (&buffer->cur());
michael@0: 
michael@0:   match_positions[0] = buffer->idx;
michael@0:   for (unsigned int i = 1; i < count; i++)
michael@0:   {
michael@0:     if (!skippy_iter.next ()) return TRACE_RETURN (false);
michael@0: 
michael@0:     match_positions[i] = skippy_iter.idx;
michael@0: 
michael@0:     unsigned int this_lig_id = _hb_glyph_info_get_lig_id (&buffer->info[skippy_iter.idx]);
michael@0:     unsigned int this_lig_comp = _hb_glyph_info_get_lig_comp (&buffer->info[skippy_iter.idx]);
michael@0: 
michael@0:     if (first_lig_id && first_lig_comp) {
michael@0:       /* If first component was attached to a previous ligature component,
michael@0:        * all subsequent components should be attached to the same ligature
michael@0:        * component, otherwise we shouldn't ligate them. */
michael@0:       if (first_lig_id != this_lig_id || first_lig_comp != this_lig_comp)
michael@0: 	return TRACE_RETURN (false);
michael@0:     } else {
michael@0:       /* If first component was NOT attached to a previous ligature component,
michael@0:        * all subsequent components should also NOT be attached to any ligature
michael@0:        * component, unless they are attached to the first component itself! */
michael@0:       if (this_lig_id && this_lig_comp && (this_lig_id != first_lig_id))
michael@0: 	return TRACE_RETURN (false);
michael@0:     }
michael@0: 
michael@0:     is_mark_ligature = is_mark_ligature && _hb_glyph_info_is_mark (&buffer->info[skippy_iter.idx]);
michael@0:     total_component_count += _hb_glyph_info_get_lig_num_comps (&buffer->info[skippy_iter.idx]);
michael@0:   }
michael@0: 
michael@0:   *end_offset = skippy_iter.idx - buffer->idx + 1;
michael@0: 
michael@0:   if (p_is_mark_ligature)
michael@0:     *p_is_mark_ligature = is_mark_ligature;
michael@0: 
michael@0:   if (p_total_component_count)
michael@0:     *p_total_component_count = total_component_count;
michael@0: 
michael@0:   return TRACE_RETURN (true);
michael@0: }
michael@0: static inline void ligate_input (hb_apply_context_t *c,
michael@0: 				 unsigned int count, /* Including the first glyph */
michael@0: 				 unsigned int match_positions[MAX_CONTEXT_LENGTH], /* Including the first glyph */
michael@0: 				 unsigned int match_length,
michael@0: 				 hb_codepoint_t lig_glyph,
michael@0: 				 bool is_mark_ligature,
michael@0: 				 unsigned int total_component_count)
michael@0: {
michael@0:   TRACE_APPLY (NULL);
michael@0: 
michael@0:   hb_buffer_t *buffer = c->buffer;
michael@0: 
michael@0:   buffer->merge_clusters (buffer->idx, buffer->idx + match_length);
michael@0: 
michael@0:   /*
michael@0:    * - If it *is* a mark ligature, we don't allocate a new ligature id, and leave
michael@0:    *   the ligature to keep its old ligature id.  This will allow it to attach to
michael@0:    *   a base ligature in GPOS.  Eg. if the sequence is: LAM,LAM,SHADDA,FATHA,HEH,
michael@0:    *   and LAM,LAM,HEH for a ligature, they will leave SHADDA and FATHA wit a
michael@0:    *   ligature id and component value of 2.  Then if SHADDA,FATHA form a ligature
michael@0:    *   later, we don't want them to lose their ligature id/component, otherwise
michael@0:    *   GPOS will fail to correctly position the mark ligature on top of the
michael@0:    *   LAM,LAM,HEH ligature.  See:
michael@0:    *     https://bugzilla.gnome.org/show_bug.cgi?id=676343
michael@0:    *
michael@0:    * - If a ligature is formed of components that some of which are also ligatures
michael@0:    *   themselves, and those ligature components had marks attached to *their*
michael@0:    *   components, we have to attach the marks to the new ligature component
michael@0:    *   positions!  Now *that*'s tricky!  And these marks may be following the
michael@0:    *   last component of the whole sequence, so we should loop forward looking
michael@0:    *   for them and update them.
michael@0:    *
michael@0:    *   Eg. the sequence is LAM,LAM,SHADDA,FATHA,HEH, and the font first forms a
michael@0:    *   'calt' ligature of LAM,HEH, leaving the SHADDA and FATHA with a ligature
michael@0:    *   id and component == 1.  Now, during 'liga', the LAM and the LAM-HEH ligature
michael@0:    *   form a LAM-LAM-HEH ligature.  We need to reassign the SHADDA and FATHA to
michael@0:    *   the new ligature with a component value of 2.
michael@0:    *
michael@0:    *   This in fact happened to a font...  See:
michael@0:    *   https://bugzilla.gnome.org/show_bug.cgi?id=437633
michael@0:    */
michael@0: 
michael@0:   unsigned int klass = is_mark_ligature ? 0 : HB_OT_LAYOUT_GLYPH_PROPS_LIGATURE;
michael@0:   unsigned int lig_id = is_mark_ligature ? 0 : _hb_allocate_lig_id (buffer);
michael@0:   unsigned int last_lig_id = _hb_glyph_info_get_lig_id (&buffer->cur());
michael@0:   unsigned int last_num_components = _hb_glyph_info_get_lig_num_comps (&buffer->cur());
michael@0:   unsigned int components_so_far = last_num_components;
michael@0: 
michael@0:   if (!is_mark_ligature)
michael@0:   {
michael@0:     _hb_glyph_info_set_lig_props_for_ligature (&buffer->cur(), lig_id, total_component_count);
michael@0:     if (_hb_glyph_info_get_general_category (&buffer->cur()) == HB_UNICODE_GENERAL_CATEGORY_NON_SPACING_MARK)
michael@0:     {
michael@0:       _hb_glyph_info_set_general_category (&buffer->cur(), HB_UNICODE_GENERAL_CATEGORY_OTHER_LETTER);
michael@0:       _hb_glyph_info_set_modified_combining_class (&buffer->cur(), 0);
michael@0:     }
michael@0:   }
michael@0:   c->replace_glyph_with_ligature (lig_glyph, klass);
michael@0: 
michael@0:   for (unsigned int i = 1; i < count; i++)
michael@0:   {
michael@0:     while (buffer->idx < match_positions[i])
michael@0:     {
michael@0:       if (!is_mark_ligature) {
michael@0: 	unsigned int new_lig_comp = components_so_far - last_num_components +
michael@0: 				    MIN (MAX (_hb_glyph_info_get_lig_comp (&buffer->cur()), 1u), last_num_components);
michael@0: 	_hb_glyph_info_set_lig_props_for_mark (&buffer->cur(), lig_id, new_lig_comp);
michael@0:       }
michael@0:       buffer->next_glyph ();
michael@0:     }
michael@0: 
michael@0:     last_lig_id = _hb_glyph_info_get_lig_id (&buffer->cur());
michael@0:     last_num_components = _hb_glyph_info_get_lig_num_comps (&buffer->cur());
michael@0:     components_so_far += last_num_components;
michael@0: 
michael@0:     /* Skip the base glyph */
michael@0:     buffer->idx++;
michael@0:   }
michael@0: 
michael@0:   if (!is_mark_ligature && last_lig_id) {
michael@0:     /* Re-adjust components for any marks following. */
michael@0:     for (unsigned int i = buffer->idx; i < buffer->len; i++) {
michael@0:       if (last_lig_id == _hb_glyph_info_get_lig_id (&buffer->info[i])) {
michael@0: 	unsigned int new_lig_comp = components_so_far - last_num_components +
michael@0: 				    MIN (MAX (_hb_glyph_info_get_lig_comp (&buffer->info[i]), 1u), last_num_components);
michael@0: 	_hb_glyph_info_set_lig_props_for_mark (&buffer->info[i], lig_id, new_lig_comp);
michael@0:       } else
michael@0: 	break;
michael@0:     }
michael@0:   }
michael@0: }
michael@0: 
michael@0: static inline bool match_backtrack (hb_apply_context_t *c,
michael@0: 				    unsigned int count,
michael@0: 				    const USHORT backtrack[],
michael@0: 				    match_func_t match_func,
michael@0: 				    const void *match_data)
michael@0: {
michael@0:   TRACE_APPLY (NULL);
michael@0: 
michael@0:   hb_apply_context_t::skipping_backward_iterator_t skippy_iter (c, c->buffer->backtrack_len (), count, true);
michael@0:   skippy_iter.set_match_func (match_func, match_data, backtrack);
michael@0:   if (skippy_iter.has_no_chance ()) return TRACE_RETURN (false);
michael@0: 
michael@0:   for (unsigned int i = 0; i < count; i++)
michael@0:     if (!skippy_iter.prev ())
michael@0:       return TRACE_RETURN (false);
michael@0: 
michael@0:   return TRACE_RETURN (true);
michael@0: }
michael@0: 
michael@0: static inline bool match_lookahead (hb_apply_context_t *c,
michael@0: 				    unsigned int count,
michael@0: 				    const USHORT lookahead[],
michael@0: 				    match_func_t match_func,
michael@0: 				    const void *match_data,
michael@0: 				    unsigned int offset)
michael@0: {
michael@0:   TRACE_APPLY (NULL);
michael@0: 
michael@0:   hb_apply_context_t::skipping_forward_iterator_t skippy_iter (c, c->buffer->idx + offset - 1, count, true);
michael@0:   skippy_iter.set_match_func (match_func, match_data, lookahead);
michael@0:   if (skippy_iter.has_no_chance ()) return TRACE_RETURN (false);
michael@0: 
michael@0:   for (unsigned int i = 0; i < count; i++)
michael@0:     if (!skippy_iter.next ())
michael@0:       return TRACE_RETURN (false);
michael@0: 
michael@0:   return TRACE_RETURN (true);
michael@0: }
michael@0: 
michael@0: 
michael@0: 
michael@0: struct LookupRecord
michael@0: {
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (c->check_struct (this));
michael@0:   }
michael@0: 
michael@0:   USHORT	sequenceIndex;		/* Index into current glyph
michael@0: 					 * sequence--first glyph = 0 */
michael@0:   USHORT	lookupListIndex;	/* Lookup to apply to that
michael@0: 					 * position--zero--based */
michael@0:   public:
michael@0:   DEFINE_SIZE_STATIC (4);
michael@0: };
michael@0: 
michael@0: 
michael@0: template <typename context_t>
michael@0: static inline void recurse_lookups (context_t *c,
michael@0: 				    unsigned int lookupCount,
michael@0: 				    const LookupRecord lookupRecord[] /* Array of LookupRecords--in design order */)
michael@0: {
michael@0:   for (unsigned int i = 0; i < lookupCount; i++)
michael@0:     c->recurse (lookupRecord[i].lookupListIndex);
michael@0: }
michael@0: 
michael@0: static inline bool apply_lookup (hb_apply_context_t *c,
michael@0: 				 unsigned int count, /* Including the first glyph */
michael@0: 				 unsigned int match_positions[MAX_CONTEXT_LENGTH], /* Including the first glyph */
michael@0: 				 unsigned int lookupCount,
michael@0: 				 const LookupRecord lookupRecord[], /* Array of LookupRecords--in design order */
michael@0: 				 unsigned int match_length)
michael@0: {
michael@0:   TRACE_APPLY (NULL);
michael@0: 
michael@0:   hb_buffer_t *buffer = c->buffer;
michael@0:   unsigned int end;
michael@0: 
michael@0:   /* All positions are distance from beginning of *output* buffer.
michael@0:    * Adjust. */
michael@0:   {
michael@0:     unsigned int bl = buffer->backtrack_len ();
michael@0:     end = bl + match_length;
michael@0: 
michael@0:     int delta = bl - buffer->idx;
michael@0:     /* Convert positions to new indexing. */
michael@0:     for (unsigned int j = 0; j < count; j++)
michael@0:       match_positions[j] += delta;
michael@0:   }
michael@0: 
michael@0:   for (unsigned int i = 0; i < lookupCount; i++)
michael@0:   {
michael@0:     unsigned int idx = lookupRecord[i].sequenceIndex;
michael@0:     if (idx >= count)
michael@0:       continue;
michael@0: 
michael@0:     buffer->move_to (match_positions[idx]);
michael@0: 
michael@0:     unsigned int orig_len = buffer->backtrack_len () + buffer->lookahead_len ();
michael@0:     if (!c->recurse (lookupRecord[i].lookupListIndex))
michael@0:       continue;
michael@0: 
michael@0:     unsigned int new_len = buffer->backtrack_len () + buffer->lookahead_len ();
michael@0:     int delta = new_len - orig_len;
michael@0: 
michael@0:     if (!delta)
michael@0:         continue;
michael@0: 
michael@0:     /* Recursed lookup changed buffer len.  Adjust. */
michael@0: 
michael@0:     /* end can't go back past the current match position. */
michael@0:     end = MAX ((int) match_positions[idx] + 1, int (end) + delta);
michael@0: 
michael@0:     unsigned int next = idx + 1; /* next now is the position after the recursed lookup. */
michael@0: 
michael@0:     if (delta > 0)
michael@0:     {
michael@0:       if (unlikely (delta + count > MAX_CONTEXT_LENGTH))
michael@0: 	break;
michael@0:     }
michael@0:     else
michael@0:     {
michael@0:       /* NOTE: delta is negative. */
michael@0:       delta = MAX (delta, (int) next - (int) count);
michael@0:       next -= delta;
michael@0:     }
michael@0: 
michael@0:     /* Shift! */
michael@0:     memmove (match_positions + next + delta, match_positions + next,
michael@0: 	     (count - next) * sizeof (match_positions[0]));
michael@0:     next += delta;
michael@0:     count += delta;
michael@0: 
michael@0:     /* Fill in new entries. */
michael@0:     for (unsigned int j = idx + 1; j < next; j++)
michael@0:       match_positions[j] = match_positions[j - 1] + 1;
michael@0: 
michael@0:     /* And fixup the rest. */
michael@0:     for (; next < count; next++)
michael@0:       match_positions[next] += delta;
michael@0:   }
michael@0: 
michael@0:   buffer->move_to (end);
michael@0: 
michael@0:   return TRACE_RETURN (true);
michael@0: }
michael@0: 
michael@0: 
michael@0: 
michael@0: /* Contextual lookups */
michael@0: 
michael@0: struct ContextClosureLookupContext
michael@0: {
michael@0:   ContextClosureFuncs funcs;
michael@0:   const void *intersects_data;
michael@0: };
michael@0: 
michael@0: struct ContextCollectGlyphsLookupContext
michael@0: {
michael@0:   ContextCollectGlyphsFuncs funcs;
michael@0:   const void *collect_data;
michael@0: };
michael@0: 
michael@0: struct ContextApplyLookupContext
michael@0: {
michael@0:   ContextApplyFuncs funcs;
michael@0:   const void *match_data;
michael@0: };
michael@0: 
michael@0: static inline void context_closure_lookup (hb_closure_context_t *c,
michael@0: 					   unsigned int inputCount, /* Including the first glyph (not matched) */
michael@0: 					   const USHORT input[], /* Array of input values--start with second glyph */
michael@0: 					   unsigned int lookupCount,
michael@0: 					   const LookupRecord lookupRecord[],
michael@0: 					   ContextClosureLookupContext &lookup_context)
michael@0: {
michael@0:   if (intersects_array (c,
michael@0: 			inputCount ? inputCount - 1 : 0, input,
michael@0: 			lookup_context.funcs.intersects, lookup_context.intersects_data))
michael@0:     recurse_lookups (c,
michael@0: 		     lookupCount, lookupRecord);
michael@0: }
michael@0: 
michael@0: static inline void context_collect_glyphs_lookup (hb_collect_glyphs_context_t *c,
michael@0: 						  unsigned int inputCount, /* Including the first glyph (not matched) */
michael@0: 						  const USHORT input[], /* Array of input values--start with second glyph */
michael@0: 						  unsigned int lookupCount,
michael@0: 						  const LookupRecord lookupRecord[],
michael@0: 						  ContextCollectGlyphsLookupContext &lookup_context)
michael@0: {
michael@0:   collect_array (c, c->input,
michael@0: 		 inputCount ? inputCount - 1 : 0, input,
michael@0: 		 lookup_context.funcs.collect, lookup_context.collect_data);
michael@0:   recurse_lookups (c,
michael@0: 		   lookupCount, lookupRecord);
michael@0: }
michael@0: 
michael@0: static inline bool context_would_apply_lookup (hb_would_apply_context_t *c,
michael@0: 					       unsigned int inputCount, /* Including the first glyph (not matched) */
michael@0: 					       const USHORT input[], /* Array of input values--start with second glyph */
michael@0: 					       unsigned int lookupCount HB_UNUSED,
michael@0: 					       const LookupRecord lookupRecord[] HB_UNUSED,
michael@0: 					       ContextApplyLookupContext &lookup_context)
michael@0: {
michael@0:   return would_match_input (c,
michael@0: 			    inputCount, input,
michael@0: 			    lookup_context.funcs.match, lookup_context.match_data);
michael@0: }
michael@0: static inline bool context_apply_lookup (hb_apply_context_t *c,
michael@0: 					 unsigned int inputCount, /* Including the first glyph (not matched) */
michael@0: 					 const USHORT input[], /* Array of input values--start with second glyph */
michael@0: 					 unsigned int lookupCount,
michael@0: 					 const LookupRecord lookupRecord[],
michael@0: 					 ContextApplyLookupContext &lookup_context)
michael@0: {
michael@0:   unsigned int match_length = 0;
michael@0:   unsigned int match_positions[MAX_CONTEXT_LENGTH];
michael@0:   return match_input (c,
michael@0: 		      inputCount, input,
michael@0: 		      lookup_context.funcs.match, lookup_context.match_data,
michael@0: 		      &match_length, match_positions)
michael@0:       && apply_lookup (c,
michael@0: 		       inputCount, match_positions,
michael@0: 		       lookupCount, lookupRecord,
michael@0: 		       match_length);
michael@0: }
michael@0: 
michael@0: struct Rule
michael@0: {
michael@0:   inline void closure (hb_closure_context_t *c, ContextClosureLookupContext &lookup_context) const
michael@0:   {
michael@0:     TRACE_CLOSURE (this);
michael@0:     const LookupRecord *lookupRecord = &StructAtOffset<LookupRecord> (input, input[0].static_size * (inputCount ? inputCount - 1 : 0));
michael@0:     context_closure_lookup (c,
michael@0: 			    inputCount, input,
michael@0: 			    lookupCount, lookupRecord,
michael@0: 			    lookup_context);
michael@0:   }
michael@0: 
michael@0:   inline void collect_glyphs (hb_collect_glyphs_context_t *c, ContextCollectGlyphsLookupContext &lookup_context) const
michael@0:   {
michael@0:     TRACE_COLLECT_GLYPHS (this);
michael@0:     const LookupRecord *lookupRecord = &StructAtOffset<LookupRecord> (input, input[0].static_size * (inputCount ? inputCount - 1 : 0));
michael@0:     context_collect_glyphs_lookup (c,
michael@0: 				   inputCount, input,
michael@0: 				   lookupCount, lookupRecord,
michael@0: 				   lookup_context);
michael@0:   }
michael@0: 
michael@0:   inline bool would_apply (hb_would_apply_context_t *c, ContextApplyLookupContext &lookup_context) const
michael@0:   {
michael@0:     TRACE_WOULD_APPLY (this);
michael@0:     const LookupRecord *lookupRecord = &StructAtOffset<LookupRecord> (input, input[0].static_size * (inputCount ? inputCount - 1 : 0));
michael@0:     return TRACE_RETURN (context_would_apply_lookup (c, inputCount, input, lookupCount, lookupRecord, lookup_context));
michael@0:   }
michael@0: 
michael@0:   inline bool apply (hb_apply_context_t *c, ContextApplyLookupContext &lookup_context) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0:     const LookupRecord *lookupRecord = &StructAtOffset<LookupRecord> (input, input[0].static_size * (inputCount ? inputCount - 1 : 0));
michael@0:     return TRACE_RETURN (context_apply_lookup (c, inputCount, input, lookupCount, lookupRecord, lookup_context));
michael@0:   }
michael@0: 
michael@0:   public:
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return inputCount.sanitize (c)
michael@0: 	&& lookupCount.sanitize (c)
michael@0: 	&& c->check_range (input,
michael@0: 			   input[0].static_size * inputCount
michael@0: 			   + lookupRecordX[0].static_size * lookupCount);
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   USHORT	inputCount;		/* Total number of glyphs in input
michael@0: 					 * glyph sequence--includes the first
michael@0: 					 * glyph */
michael@0:   USHORT	lookupCount;		/* Number of LookupRecords */
michael@0:   USHORT	input[VAR];		/* Array of match inputs--start with
michael@0: 					 * second glyph */
michael@0:   LookupRecord	lookupRecordX[VAR];	/* Array of LookupRecords--in
michael@0: 					 * design order */
michael@0:   public:
michael@0:   DEFINE_SIZE_ARRAY2 (4, input, lookupRecordX);
michael@0: };
michael@0: 
michael@0: struct RuleSet
michael@0: {
michael@0:   inline void closure (hb_closure_context_t *c, ContextClosureLookupContext &lookup_context) const
michael@0:   {
michael@0:     TRACE_CLOSURE (this);
michael@0:     unsigned int num_rules = rule.len;
michael@0:     for (unsigned int i = 0; i < num_rules; i++)
michael@0:       (this+rule[i]).closure (c, lookup_context);
michael@0:   }
michael@0: 
michael@0:   inline void collect_glyphs (hb_collect_glyphs_context_t *c, ContextCollectGlyphsLookupContext &lookup_context) const
michael@0:   {
michael@0:     TRACE_COLLECT_GLYPHS (this);
michael@0:     unsigned int num_rules = rule.len;
michael@0:     for (unsigned int i = 0; i < num_rules; i++)
michael@0:       (this+rule[i]).collect_glyphs (c, lookup_context);
michael@0:   }
michael@0: 
michael@0:   inline bool would_apply (hb_would_apply_context_t *c, ContextApplyLookupContext &lookup_context) const
michael@0:   {
michael@0:     TRACE_WOULD_APPLY (this);
michael@0:     unsigned int num_rules = rule.len;
michael@0:     for (unsigned int i = 0; i < num_rules; i++)
michael@0:     {
michael@0:       if ((this+rule[i]).would_apply (c, lookup_context))
michael@0:         return TRACE_RETURN (true);
michael@0:     }
michael@0:     return TRACE_RETURN (false);
michael@0:   }
michael@0: 
michael@0:   inline bool apply (hb_apply_context_t *c, ContextApplyLookupContext &lookup_context) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0:     unsigned int num_rules = rule.len;
michael@0:     for (unsigned int i = 0; i < num_rules; i++)
michael@0:     {
michael@0:       if ((this+rule[i]).apply (c, lookup_context))
michael@0:         return TRACE_RETURN (true);
michael@0:     }
michael@0:     return TRACE_RETURN (false);
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (rule.sanitize (c, this));
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   OffsetArrayOf<Rule>
michael@0: 		rule;			/* Array of Rule tables
michael@0: 					 * ordered by preference */
michael@0:   public:
michael@0:   DEFINE_SIZE_ARRAY (2, rule);
michael@0: };
michael@0: 
michael@0: 
michael@0: struct ContextFormat1
michael@0: {
michael@0:   inline void closure (hb_closure_context_t *c) const
michael@0:   {
michael@0:     TRACE_CLOSURE (this);
michael@0: 
michael@0:     const Coverage &cov = (this+coverage);
michael@0: 
michael@0:     struct ContextClosureLookupContext lookup_context = {
michael@0:       {intersects_glyph},
michael@0:       NULL
michael@0:     };
michael@0: 
michael@0:     unsigned int count = ruleSet.len;
michael@0:     for (unsigned int i = 0; i < count; i++)
michael@0:       if (cov.intersects_coverage (c->glyphs, i)) {
michael@0: 	const RuleSet &rule_set = this+ruleSet[i];
michael@0: 	rule_set.closure (c, lookup_context);
michael@0:       }
michael@0:   }
michael@0: 
michael@0:   inline void collect_glyphs (hb_collect_glyphs_context_t *c) const
michael@0:   {
michael@0:     TRACE_COLLECT_GLYPHS (this);
michael@0:     (this+coverage).add_coverage (c->input);
michael@0: 
michael@0:     struct ContextCollectGlyphsLookupContext lookup_context = {
michael@0:       {collect_glyph},
michael@0:       NULL
michael@0:     };
michael@0: 
michael@0:     unsigned int count = ruleSet.len;
michael@0:     for (unsigned int i = 0; i < count; i++)
michael@0:       (this+ruleSet[i]).collect_glyphs (c, lookup_context);
michael@0:   }
michael@0: 
michael@0:   inline bool would_apply (hb_would_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_WOULD_APPLY (this);
michael@0: 
michael@0:     const RuleSet &rule_set = this+ruleSet[(this+coverage).get_coverage (c->glyphs[0])];
michael@0:     struct ContextApplyLookupContext lookup_context = {
michael@0:       {match_glyph},
michael@0:       NULL
michael@0:     };
michael@0:     return TRACE_RETURN (rule_set.would_apply (c, lookup_context));
michael@0:   }
michael@0: 
michael@0:   inline const Coverage &get_coverage (void) const
michael@0:   {
michael@0:     return this+coverage;
michael@0:   }
michael@0: 
michael@0:   inline bool apply (hb_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0:     unsigned int index = (this+coverage).get_coverage (c->buffer->cur().codepoint);
michael@0:     if (likely (index == NOT_COVERED))
michael@0:       return TRACE_RETURN (false);
michael@0: 
michael@0:     const RuleSet &rule_set = this+ruleSet[index];
michael@0:     struct ContextApplyLookupContext lookup_context = {
michael@0:       {match_glyph},
michael@0:       NULL
michael@0:     };
michael@0:     return TRACE_RETURN (rule_set.apply (c, lookup_context));
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (coverage.sanitize (c, this) && ruleSet.sanitize (c, this));
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   USHORT	format;			/* Format identifier--format = 1 */
michael@0:   OffsetTo<Coverage>
michael@0: 		coverage;		/* Offset to Coverage table--from
michael@0: 					 * beginning of table */
michael@0:   OffsetArrayOf<RuleSet>
michael@0: 		ruleSet;		/* Array of RuleSet tables
michael@0: 					 * ordered by Coverage Index */
michael@0:   public:
michael@0:   DEFINE_SIZE_ARRAY (6, ruleSet);
michael@0: };
michael@0: 
michael@0: 
michael@0: struct ContextFormat2
michael@0: {
michael@0:   inline void closure (hb_closure_context_t *c) const
michael@0:   {
michael@0:     TRACE_CLOSURE (this);
michael@0:     if (!(this+coverage).intersects (c->glyphs))
michael@0:       return;
michael@0: 
michael@0:     const ClassDef &class_def = this+classDef;
michael@0: 
michael@0:     struct ContextClosureLookupContext lookup_context = {
michael@0:       {intersects_class},
michael@0:       &class_def
michael@0:     };
michael@0: 
michael@0:     unsigned int count = ruleSet.len;
michael@0:     for (unsigned int i = 0; i < count; i++)
michael@0:       if (class_def.intersects_class (c->glyphs, i)) {
michael@0: 	const RuleSet &rule_set = this+ruleSet[i];
michael@0: 	rule_set.closure (c, lookup_context);
michael@0:       }
michael@0:   }
michael@0: 
michael@0:   inline void collect_glyphs (hb_collect_glyphs_context_t *c) const
michael@0:   {
michael@0:     TRACE_COLLECT_GLYPHS (this);
michael@0:     (this+coverage).add_coverage (c->input);
michael@0: 
michael@0:     const ClassDef &class_def = this+classDef;
michael@0:     struct ContextCollectGlyphsLookupContext lookup_context = {
michael@0:       {collect_class},
michael@0:       &class_def
michael@0:     };
michael@0: 
michael@0:     unsigned int count = ruleSet.len;
michael@0:     for (unsigned int i = 0; i < count; i++)
michael@0:       (this+ruleSet[i]).collect_glyphs (c, lookup_context);
michael@0:   }
michael@0: 
michael@0:   inline bool would_apply (hb_would_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_WOULD_APPLY (this);
michael@0: 
michael@0:     const ClassDef &class_def = this+classDef;
michael@0:     unsigned int index = class_def.get_class (c->glyphs[0]);
michael@0:     const RuleSet &rule_set = this+ruleSet[index];
michael@0:     struct ContextApplyLookupContext lookup_context = {
michael@0:       {match_class},
michael@0:       &class_def
michael@0:     };
michael@0:     return TRACE_RETURN (rule_set.would_apply (c, lookup_context));
michael@0:   }
michael@0: 
michael@0:   inline const Coverage &get_coverage (void) const
michael@0:   {
michael@0:     return this+coverage;
michael@0:   }
michael@0: 
michael@0:   inline bool apply (hb_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0:     unsigned int index = (this+coverage).get_coverage (c->buffer->cur().codepoint);
michael@0:     if (likely (index == NOT_COVERED)) return TRACE_RETURN (false);
michael@0: 
michael@0:     const ClassDef &class_def = this+classDef;
michael@0:     index = class_def.get_class (c->buffer->cur().codepoint);
michael@0:     const RuleSet &rule_set = this+ruleSet[index];
michael@0:     struct ContextApplyLookupContext lookup_context = {
michael@0:       {match_class},
michael@0:       &class_def
michael@0:     };
michael@0:     return TRACE_RETURN (rule_set.apply (c, lookup_context));
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (coverage.sanitize (c, this) && classDef.sanitize (c, this) && ruleSet.sanitize (c, this));
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   USHORT	format;			/* Format identifier--format = 2 */
michael@0:   OffsetTo<Coverage>
michael@0: 		coverage;		/* Offset to Coverage table--from
michael@0: 					 * beginning of table */
michael@0:   OffsetTo<ClassDef>
michael@0: 		classDef;		/* Offset to glyph ClassDef table--from
michael@0: 					 * beginning of table */
michael@0:   OffsetArrayOf<RuleSet>
michael@0: 		ruleSet;		/* Array of RuleSet tables
michael@0: 					 * ordered by class */
michael@0:   public:
michael@0:   DEFINE_SIZE_ARRAY (8, ruleSet);
michael@0: };
michael@0: 
michael@0: 
michael@0: struct ContextFormat3
michael@0: {
michael@0:   inline void closure (hb_closure_context_t *c) const
michael@0:   {
michael@0:     TRACE_CLOSURE (this);
michael@0:     if (!(this+coverage[0]).intersects (c->glyphs))
michael@0:       return;
michael@0: 
michael@0:     const LookupRecord *lookupRecord = &StructAtOffset<LookupRecord> (coverage, coverage[0].static_size * glyphCount);
michael@0:     struct ContextClosureLookupContext lookup_context = {
michael@0:       {intersects_coverage},
michael@0:       this
michael@0:     };
michael@0:     context_closure_lookup (c,
michael@0: 			    glyphCount, (const USHORT *) (coverage + 1),
michael@0: 			    lookupCount, lookupRecord,
michael@0: 			    lookup_context);
michael@0:   }
michael@0: 
michael@0:   inline void collect_glyphs (hb_collect_glyphs_context_t *c) const
michael@0:   {
michael@0:     TRACE_COLLECT_GLYPHS (this);
michael@0:     (this+coverage[0]).add_coverage (c->input);
michael@0: 
michael@0:     const LookupRecord *lookupRecord = &StructAtOffset<LookupRecord> (coverage, coverage[0].static_size * glyphCount);
michael@0:     struct ContextCollectGlyphsLookupContext lookup_context = {
michael@0:       {collect_coverage},
michael@0:       this
michael@0:     };
michael@0: 
michael@0:     context_collect_glyphs_lookup (c,
michael@0: 				   glyphCount, (const USHORT *) (coverage + 1),
michael@0: 				   lookupCount, lookupRecord,
michael@0: 				   lookup_context);
michael@0:   }
michael@0: 
michael@0:   inline bool would_apply (hb_would_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_WOULD_APPLY (this);
michael@0: 
michael@0:     const LookupRecord *lookupRecord = &StructAtOffset<LookupRecord> (coverage, coverage[0].static_size * glyphCount);
michael@0:     struct ContextApplyLookupContext lookup_context = {
michael@0:       {match_coverage},
michael@0:       this
michael@0:     };
michael@0:     return TRACE_RETURN (context_would_apply_lookup (c, glyphCount, (const USHORT *) (coverage + 1), lookupCount, lookupRecord, lookup_context));
michael@0:   }
michael@0: 
michael@0:   inline const Coverage &get_coverage (void) const
michael@0:   {
michael@0:     return this+coverage[0];
michael@0:   }
michael@0: 
michael@0:   inline bool apply (hb_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0:     unsigned int index = (this+coverage[0]).get_coverage (c->buffer->cur().codepoint);
michael@0:     if (likely (index == NOT_COVERED)) return TRACE_RETURN (false);
michael@0: 
michael@0:     const LookupRecord *lookupRecord = &StructAtOffset<LookupRecord> (coverage, coverage[0].static_size * glyphCount);
michael@0:     struct ContextApplyLookupContext lookup_context = {
michael@0:       {match_coverage},
michael@0:       this
michael@0:     };
michael@0:     return TRACE_RETURN (context_apply_lookup (c, glyphCount, (const USHORT *) (coverage + 1), lookupCount, lookupRecord, lookup_context));
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     if (!c->check_struct (this)) return TRACE_RETURN (false);
michael@0:     unsigned int count = glyphCount;
michael@0:     if (!c->check_array (coverage, coverage[0].static_size, count)) return TRACE_RETURN (false);
michael@0:     for (unsigned int i = 0; i < count; i++)
michael@0:       if (!coverage[i].sanitize (c, this)) return TRACE_RETURN (false);
michael@0:     LookupRecord *lookupRecord = &StructAtOffset<LookupRecord> (coverage, coverage[0].static_size * count);
michael@0:     return TRACE_RETURN (c->check_array (lookupRecord, lookupRecord[0].static_size, lookupCount));
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   USHORT	format;			/* Format identifier--format = 3 */
michael@0:   USHORT	glyphCount;		/* Number of glyphs in the input glyph
michael@0: 					 * sequence */
michael@0:   USHORT	lookupCount;		/* Number of LookupRecords */
michael@0:   OffsetTo<Coverage>
michael@0: 		coverage[VAR];		/* Array of offsets to Coverage
michael@0: 					 * table in glyph sequence order */
michael@0:   LookupRecord	lookupRecordX[VAR];	/* Array of LookupRecords--in
michael@0: 					 * design order */
michael@0:   public:
michael@0:   DEFINE_SIZE_ARRAY2 (6, coverage, lookupRecordX);
michael@0: };
michael@0: 
michael@0: struct Context
michael@0: {
michael@0:   template <typename context_t>
michael@0:   inline typename context_t::return_t dispatch (context_t *c) const
michael@0:   {
michael@0:     TRACE_DISPATCH (this);
michael@0:     switch (u.format) {
michael@0:     case 1: return TRACE_RETURN (c->dispatch (u.format1));
michael@0:     case 2: return TRACE_RETURN (c->dispatch (u.format2));
michael@0:     case 3: return TRACE_RETURN (c->dispatch (u.format3));
michael@0:     default:return TRACE_RETURN (c->default_return_value ());
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     if (!u.format.sanitize (c)) return TRACE_RETURN (false);
michael@0:     switch (u.format) {
michael@0:     case 1: return TRACE_RETURN (u.format1.sanitize (c));
michael@0:     case 2: return TRACE_RETURN (u.format2.sanitize (c));
michael@0:     case 3: return TRACE_RETURN (u.format3.sanitize (c));
michael@0:     default:return TRACE_RETURN (true);
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   union {
michael@0:   USHORT		format;		/* Format identifier */
michael@0:   ContextFormat1	format1;
michael@0:   ContextFormat2	format2;
michael@0:   ContextFormat3	format3;
michael@0:   } u;
michael@0: };
michael@0: 
michael@0: 
michael@0: /* Chaining Contextual lookups */
michael@0: 
michael@0: struct ChainContextClosureLookupContext
michael@0: {
michael@0:   ContextClosureFuncs funcs;
michael@0:   const void *intersects_data[3];
michael@0: };
michael@0: 
michael@0: struct ChainContextCollectGlyphsLookupContext
michael@0: {
michael@0:   ContextCollectGlyphsFuncs funcs;
michael@0:   const void *collect_data[3];
michael@0: };
michael@0: 
michael@0: struct ChainContextApplyLookupContext
michael@0: {
michael@0:   ContextApplyFuncs funcs;
michael@0:   const void *match_data[3];
michael@0: };
michael@0: 
michael@0: static inline void chain_context_closure_lookup (hb_closure_context_t *c,
michael@0: 						 unsigned int backtrackCount,
michael@0: 						 const USHORT backtrack[],
michael@0: 						 unsigned int inputCount, /* Including the first glyph (not matched) */
michael@0: 						 const USHORT input[], /* Array of input values--start with second glyph */
michael@0: 						 unsigned int lookaheadCount,
michael@0: 						 const USHORT lookahead[],
michael@0: 						 unsigned int lookupCount,
michael@0: 						 const LookupRecord lookupRecord[],
michael@0: 						 ChainContextClosureLookupContext &lookup_context)
michael@0: {
michael@0:   if (intersects_array (c,
michael@0: 			backtrackCount, backtrack,
michael@0: 			lookup_context.funcs.intersects, lookup_context.intersects_data[0])
michael@0:    && intersects_array (c,
michael@0: 			inputCount ? inputCount - 1 : 0, input,
michael@0: 			lookup_context.funcs.intersects, lookup_context.intersects_data[1])
michael@0:    && intersects_array (c,
michael@0: 		       lookaheadCount, lookahead,
michael@0: 		       lookup_context.funcs.intersects, lookup_context.intersects_data[2]))
michael@0:     recurse_lookups (c,
michael@0: 		     lookupCount, lookupRecord);
michael@0: }
michael@0: 
michael@0: static inline void chain_context_collect_glyphs_lookup (hb_collect_glyphs_context_t *c,
michael@0: 						        unsigned int backtrackCount,
michael@0: 						        const USHORT backtrack[],
michael@0: 						        unsigned int inputCount, /* Including the first glyph (not matched) */
michael@0: 						        const USHORT input[], /* Array of input values--start with second glyph */
michael@0: 						        unsigned int lookaheadCount,
michael@0: 						        const USHORT lookahead[],
michael@0: 						        unsigned int lookupCount,
michael@0: 						        const LookupRecord lookupRecord[],
michael@0: 						        ChainContextCollectGlyphsLookupContext &lookup_context)
michael@0: {
michael@0:   collect_array (c, c->before,
michael@0: 		 backtrackCount, backtrack,
michael@0: 		 lookup_context.funcs.collect, lookup_context.collect_data[0]);
michael@0:   collect_array (c, c->input,
michael@0: 		 inputCount ? inputCount - 1 : 0, input,
michael@0: 		 lookup_context.funcs.collect, lookup_context.collect_data[1]);
michael@0:   collect_array (c, c->after,
michael@0: 		 lookaheadCount, lookahead,
michael@0: 		 lookup_context.funcs.collect, lookup_context.collect_data[2]);
michael@0:   recurse_lookups (c,
michael@0: 		   lookupCount, lookupRecord);
michael@0: }
michael@0: 
michael@0: static inline bool chain_context_would_apply_lookup (hb_would_apply_context_t *c,
michael@0: 						     unsigned int backtrackCount,
michael@0: 						     const USHORT backtrack[] HB_UNUSED,
michael@0: 						     unsigned int inputCount, /* Including the first glyph (not matched) */
michael@0: 						     const USHORT input[], /* Array of input values--start with second glyph */
michael@0: 						     unsigned int lookaheadCount,
michael@0: 						     const USHORT lookahead[] HB_UNUSED,
michael@0: 						     unsigned int lookupCount HB_UNUSED,
michael@0: 						     const LookupRecord lookupRecord[] HB_UNUSED,
michael@0: 						     ChainContextApplyLookupContext &lookup_context)
michael@0: {
michael@0:   return (c->zero_context ? !backtrackCount && !lookaheadCount : true)
michael@0:       && would_match_input (c,
michael@0: 			    inputCount, input,
michael@0: 			    lookup_context.funcs.match, lookup_context.match_data[1]);
michael@0: }
michael@0: 
michael@0: static inline bool chain_context_apply_lookup (hb_apply_context_t *c,
michael@0: 					       unsigned int backtrackCount,
michael@0: 					       const USHORT backtrack[],
michael@0: 					       unsigned int inputCount, /* Including the first glyph (not matched) */
michael@0: 					       const USHORT input[], /* Array of input values--start with second glyph */
michael@0: 					       unsigned int lookaheadCount,
michael@0: 					       const USHORT lookahead[],
michael@0: 					       unsigned int lookupCount,
michael@0: 					       const LookupRecord lookupRecord[],
michael@0: 					       ChainContextApplyLookupContext &lookup_context)
michael@0: {
michael@0:   unsigned int match_length = 0;
michael@0:   unsigned int match_positions[MAX_CONTEXT_LENGTH];
michael@0:   return match_input (c,
michael@0: 		      inputCount, input,
michael@0: 		      lookup_context.funcs.match, lookup_context.match_data[1],
michael@0: 		      &match_length, match_positions)
michael@0:       && match_backtrack (c,
michael@0: 			  backtrackCount, backtrack,
michael@0: 			  lookup_context.funcs.match, lookup_context.match_data[0])
michael@0:       && match_lookahead (c,
michael@0: 			  lookaheadCount, lookahead,
michael@0: 			  lookup_context.funcs.match, lookup_context.match_data[2],
michael@0: 			  match_length)
michael@0:       && apply_lookup (c,
michael@0: 		       inputCount, match_positions,
michael@0: 		       lookupCount, lookupRecord,
michael@0: 		       match_length);
michael@0: }
michael@0: 
michael@0: struct ChainRule
michael@0: {
michael@0:   inline void closure (hb_closure_context_t *c, ChainContextClosureLookupContext &lookup_context) const
michael@0:   {
michael@0:     TRACE_CLOSURE (this);
michael@0:     const HeadlessArrayOf<USHORT> &input = StructAfter<HeadlessArrayOf<USHORT> > (backtrack);
michael@0:     const ArrayOf<USHORT> &lookahead = StructAfter<ArrayOf<USHORT> > (input);
michael@0:     const ArrayOf<LookupRecord> &lookup = StructAfter<ArrayOf<LookupRecord> > (lookahead);
michael@0:     chain_context_closure_lookup (c,
michael@0: 				  backtrack.len, backtrack.array,
michael@0: 				  input.len, input.array,
michael@0: 				  lookahead.len, lookahead.array,
michael@0: 				  lookup.len, lookup.array,
michael@0: 				  lookup_context);
michael@0:   }
michael@0: 
michael@0:   inline void collect_glyphs (hb_collect_glyphs_context_t *c, ChainContextCollectGlyphsLookupContext &lookup_context) const
michael@0:   {
michael@0:     TRACE_COLLECT_GLYPHS (this);
michael@0:     const HeadlessArrayOf<USHORT> &input = StructAfter<HeadlessArrayOf<USHORT> > (backtrack);
michael@0:     const ArrayOf<USHORT> &lookahead = StructAfter<ArrayOf<USHORT> > (input);
michael@0:     const ArrayOf<LookupRecord> &lookup = StructAfter<ArrayOf<LookupRecord> > (lookahead);
michael@0:     chain_context_collect_glyphs_lookup (c,
michael@0: 					 backtrack.len, backtrack.array,
michael@0: 					 input.len, input.array,
michael@0: 					 lookahead.len, lookahead.array,
michael@0: 					 lookup.len, lookup.array,
michael@0: 					 lookup_context);
michael@0:   }
michael@0: 
michael@0:   inline bool would_apply (hb_would_apply_context_t *c, ChainContextApplyLookupContext &lookup_context) const
michael@0:   {
michael@0:     TRACE_WOULD_APPLY (this);
michael@0:     const HeadlessArrayOf<USHORT> &input = StructAfter<HeadlessArrayOf<USHORT> > (backtrack);
michael@0:     const ArrayOf<USHORT> &lookahead = StructAfter<ArrayOf<USHORT> > (input);
michael@0:     const ArrayOf<LookupRecord> &lookup = StructAfter<ArrayOf<LookupRecord> > (lookahead);
michael@0:     return TRACE_RETURN (chain_context_would_apply_lookup (c,
michael@0: 							   backtrack.len, backtrack.array,
michael@0: 							   input.len, input.array,
michael@0: 							   lookahead.len, lookahead.array, lookup.len,
michael@0: 							   lookup.array, lookup_context));
michael@0:   }
michael@0: 
michael@0:   inline bool apply (hb_apply_context_t *c, ChainContextApplyLookupContext &lookup_context) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0:     const HeadlessArrayOf<USHORT> &input = StructAfter<HeadlessArrayOf<USHORT> > (backtrack);
michael@0:     const ArrayOf<USHORT> &lookahead = StructAfter<ArrayOf<USHORT> > (input);
michael@0:     const ArrayOf<LookupRecord> &lookup = StructAfter<ArrayOf<LookupRecord> > (lookahead);
michael@0:     return TRACE_RETURN (chain_context_apply_lookup (c,
michael@0: 						     backtrack.len, backtrack.array,
michael@0: 						     input.len, input.array,
michael@0: 						     lookahead.len, lookahead.array, lookup.len,
michael@0: 						     lookup.array, lookup_context));
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     if (!backtrack.sanitize (c)) return TRACE_RETURN (false);
michael@0:     HeadlessArrayOf<USHORT> &input = StructAfter<HeadlessArrayOf<USHORT> > (backtrack);
michael@0:     if (!input.sanitize (c)) return TRACE_RETURN (false);
michael@0:     ArrayOf<USHORT> &lookahead = StructAfter<ArrayOf<USHORT> > (input);
michael@0:     if (!lookahead.sanitize (c)) return TRACE_RETURN (false);
michael@0:     ArrayOf<LookupRecord> &lookup = StructAfter<ArrayOf<LookupRecord> > (lookahead);
michael@0:     return TRACE_RETURN (lookup.sanitize (c));
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   ArrayOf<USHORT>
michael@0: 		backtrack;		/* Array of backtracking values
michael@0: 					 * (to be matched before the input
michael@0: 					 * sequence) */
michael@0:   HeadlessArrayOf<USHORT>
michael@0: 		inputX;			/* Array of input values (start with
michael@0: 					 * second glyph) */
michael@0:   ArrayOf<USHORT>
michael@0: 		lookaheadX;		/* Array of lookahead values's (to be
michael@0: 					 * matched after the input sequence) */
michael@0:   ArrayOf<LookupRecord>
michael@0: 		lookupX;		/* Array of LookupRecords--in
michael@0: 					 * design order) */
michael@0:   public:
michael@0:   DEFINE_SIZE_MIN (8);
michael@0: };
michael@0: 
michael@0: struct ChainRuleSet
michael@0: {
michael@0:   inline void closure (hb_closure_context_t *c, ChainContextClosureLookupContext &lookup_context) const
michael@0:   {
michael@0:     TRACE_CLOSURE (this);
michael@0:     unsigned int num_rules = rule.len;
michael@0:     for (unsigned int i = 0; i < num_rules; i++)
michael@0:       (this+rule[i]).closure (c, lookup_context);
michael@0:   }
michael@0: 
michael@0:   inline void collect_glyphs (hb_collect_glyphs_context_t *c, ChainContextCollectGlyphsLookupContext &lookup_context) const
michael@0:   {
michael@0:     TRACE_COLLECT_GLYPHS (this);
michael@0:     unsigned int num_rules = rule.len;
michael@0:     for (unsigned int i = 0; i < num_rules; i++)
michael@0:       (this+rule[i]).collect_glyphs (c, lookup_context);
michael@0:   }
michael@0: 
michael@0:   inline bool would_apply (hb_would_apply_context_t *c, ChainContextApplyLookupContext &lookup_context) const
michael@0:   {
michael@0:     TRACE_WOULD_APPLY (this);
michael@0:     unsigned int num_rules = rule.len;
michael@0:     for (unsigned int i = 0; i < num_rules; i++)
michael@0:       if ((this+rule[i]).would_apply (c, lookup_context))
michael@0:         return TRACE_RETURN (true);
michael@0: 
michael@0:     return TRACE_RETURN (false);
michael@0:   }
michael@0: 
michael@0:   inline bool apply (hb_apply_context_t *c, ChainContextApplyLookupContext &lookup_context) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0:     unsigned int num_rules = rule.len;
michael@0:     for (unsigned int i = 0; i < num_rules; i++)
michael@0:       if ((this+rule[i]).apply (c, lookup_context))
michael@0:         return TRACE_RETURN (true);
michael@0: 
michael@0:     return TRACE_RETURN (false);
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (rule.sanitize (c, this));
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   OffsetArrayOf<ChainRule>
michael@0: 		rule;			/* Array of ChainRule tables
michael@0: 					 * ordered by preference */
michael@0:   public:
michael@0:   DEFINE_SIZE_ARRAY (2, rule);
michael@0: };
michael@0: 
michael@0: struct ChainContextFormat1
michael@0: {
michael@0:   inline void closure (hb_closure_context_t *c) const
michael@0:   {
michael@0:     TRACE_CLOSURE (this);
michael@0:     const Coverage &cov = (this+coverage);
michael@0: 
michael@0:     struct ChainContextClosureLookupContext lookup_context = {
michael@0:       {intersects_glyph},
michael@0:       {NULL, NULL, NULL}
michael@0:     };
michael@0: 
michael@0:     unsigned int count = ruleSet.len;
michael@0:     for (unsigned int i = 0; i < count; i++)
michael@0:       if (cov.intersects_coverage (c->glyphs, i)) {
michael@0: 	const ChainRuleSet &rule_set = this+ruleSet[i];
michael@0: 	rule_set.closure (c, lookup_context);
michael@0:       }
michael@0:   }
michael@0: 
michael@0:   inline void collect_glyphs (hb_collect_glyphs_context_t *c) const
michael@0:   {
michael@0:     TRACE_COLLECT_GLYPHS (this);
michael@0:     (this+coverage).add_coverage (c->input);
michael@0: 
michael@0:     struct ChainContextCollectGlyphsLookupContext lookup_context = {
michael@0:       {collect_glyph},
michael@0:       {NULL, NULL, NULL}
michael@0:     };
michael@0: 
michael@0:     unsigned int count = ruleSet.len;
michael@0:     for (unsigned int i = 0; i < count; i++)
michael@0:       (this+ruleSet[i]).collect_glyphs (c, lookup_context);
michael@0:   }
michael@0: 
michael@0:   inline bool would_apply (hb_would_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_WOULD_APPLY (this);
michael@0: 
michael@0:     const ChainRuleSet &rule_set = this+ruleSet[(this+coverage).get_coverage (c->glyphs[0])];
michael@0:     struct ChainContextApplyLookupContext lookup_context = {
michael@0:       {match_glyph},
michael@0:       {NULL, NULL, NULL}
michael@0:     };
michael@0:     return TRACE_RETURN (rule_set.would_apply (c, lookup_context));
michael@0:   }
michael@0: 
michael@0:   inline const Coverage &get_coverage (void) const
michael@0:   {
michael@0:     return this+coverage;
michael@0:   }
michael@0: 
michael@0:   inline bool apply (hb_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0:     unsigned int index = (this+coverage).get_coverage (c->buffer->cur().codepoint);
michael@0:     if (likely (index == NOT_COVERED)) return TRACE_RETURN (false);
michael@0: 
michael@0:     const ChainRuleSet &rule_set = this+ruleSet[index];
michael@0:     struct ChainContextApplyLookupContext lookup_context = {
michael@0:       {match_glyph},
michael@0:       {NULL, NULL, NULL}
michael@0:     };
michael@0:     return TRACE_RETURN (rule_set.apply (c, lookup_context));
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (coverage.sanitize (c, this) && ruleSet.sanitize (c, this));
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   USHORT	format;			/* Format identifier--format = 1 */
michael@0:   OffsetTo<Coverage>
michael@0: 		coverage;		/* Offset to Coverage table--from
michael@0: 					 * beginning of table */
michael@0:   OffsetArrayOf<ChainRuleSet>
michael@0: 		ruleSet;		/* Array of ChainRuleSet tables
michael@0: 					 * ordered by Coverage Index */
michael@0:   public:
michael@0:   DEFINE_SIZE_ARRAY (6, ruleSet);
michael@0: };
michael@0: 
michael@0: struct ChainContextFormat2
michael@0: {
michael@0:   inline void closure (hb_closure_context_t *c) const
michael@0:   {
michael@0:     TRACE_CLOSURE (this);
michael@0:     if (!(this+coverage).intersects (c->glyphs))
michael@0:       return;
michael@0: 
michael@0:     const ClassDef &backtrack_class_def = this+backtrackClassDef;
michael@0:     const ClassDef &input_class_def = this+inputClassDef;
michael@0:     const ClassDef &lookahead_class_def = this+lookaheadClassDef;
michael@0: 
michael@0:     struct ChainContextClosureLookupContext lookup_context = {
michael@0:       {intersects_class},
michael@0:       {&backtrack_class_def,
michael@0:        &input_class_def,
michael@0:        &lookahead_class_def}
michael@0:     };
michael@0: 
michael@0:     unsigned int count = ruleSet.len;
michael@0:     for (unsigned int i = 0; i < count; i++)
michael@0:       if (input_class_def.intersects_class (c->glyphs, i)) {
michael@0: 	const ChainRuleSet &rule_set = this+ruleSet[i];
michael@0: 	rule_set.closure (c, lookup_context);
michael@0:       }
michael@0:   }
michael@0: 
michael@0:   inline void collect_glyphs (hb_collect_glyphs_context_t *c) const
michael@0:   {
michael@0:     TRACE_COLLECT_GLYPHS (this);
michael@0:     (this+coverage).add_coverage (c->input);
michael@0: 
michael@0:     const ClassDef &backtrack_class_def = this+backtrackClassDef;
michael@0:     const ClassDef &input_class_def = this+inputClassDef;
michael@0:     const ClassDef &lookahead_class_def = this+lookaheadClassDef;
michael@0: 
michael@0:     struct ChainContextCollectGlyphsLookupContext lookup_context = {
michael@0:       {collect_class},
michael@0:       {&backtrack_class_def,
michael@0:        &input_class_def,
michael@0:        &lookahead_class_def}
michael@0:     };
michael@0: 
michael@0:     unsigned int count = ruleSet.len;
michael@0:     for (unsigned int i = 0; i < count; i++)
michael@0:       (this+ruleSet[i]).collect_glyphs (c, lookup_context);
michael@0:   }
michael@0: 
michael@0:   inline bool would_apply (hb_would_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_WOULD_APPLY (this);
michael@0: 
michael@0:     const ClassDef &backtrack_class_def = this+backtrackClassDef;
michael@0:     const ClassDef &input_class_def = this+inputClassDef;
michael@0:     const ClassDef &lookahead_class_def = this+lookaheadClassDef;
michael@0: 
michael@0:     unsigned int index = input_class_def.get_class (c->glyphs[0]);
michael@0:     const ChainRuleSet &rule_set = this+ruleSet[index];
michael@0:     struct ChainContextApplyLookupContext lookup_context = {
michael@0:       {match_class},
michael@0:       {&backtrack_class_def,
michael@0:        &input_class_def,
michael@0:        &lookahead_class_def}
michael@0:     };
michael@0:     return TRACE_RETURN (rule_set.would_apply (c, lookup_context));
michael@0:   }
michael@0: 
michael@0:   inline const Coverage &get_coverage (void) const
michael@0:   {
michael@0:     return this+coverage;
michael@0:   }
michael@0: 
michael@0:   inline bool apply (hb_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0:     unsigned int index = (this+coverage).get_coverage (c->buffer->cur().codepoint);
michael@0:     if (likely (index == NOT_COVERED)) return TRACE_RETURN (false);
michael@0: 
michael@0:     const ClassDef &backtrack_class_def = this+backtrackClassDef;
michael@0:     const ClassDef &input_class_def = this+inputClassDef;
michael@0:     const ClassDef &lookahead_class_def = this+lookaheadClassDef;
michael@0: 
michael@0:     index = input_class_def.get_class (c->buffer->cur().codepoint);
michael@0:     const ChainRuleSet &rule_set = this+ruleSet[index];
michael@0:     struct ChainContextApplyLookupContext lookup_context = {
michael@0:       {match_class},
michael@0:       {&backtrack_class_def,
michael@0:        &input_class_def,
michael@0:        &lookahead_class_def}
michael@0:     };
michael@0:     return TRACE_RETURN (rule_set.apply (c, lookup_context));
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (coverage.sanitize (c, this) && backtrackClassDef.sanitize (c, this) &&
michael@0: 			 inputClassDef.sanitize (c, this) && lookaheadClassDef.sanitize (c, this) &&
michael@0: 			 ruleSet.sanitize (c, this));
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   USHORT	format;			/* Format identifier--format = 2 */
michael@0:   OffsetTo<Coverage>
michael@0: 		coverage;		/* Offset to Coverage table--from
michael@0: 					 * beginning of table */
michael@0:   OffsetTo<ClassDef>
michael@0: 		backtrackClassDef;	/* Offset to glyph ClassDef table
michael@0: 					 * containing backtrack sequence
michael@0: 					 * data--from beginning of table */
michael@0:   OffsetTo<ClassDef>
michael@0: 		inputClassDef;		/* Offset to glyph ClassDef
michael@0: 					 * table containing input sequence
michael@0: 					 * data--from beginning of table */
michael@0:   OffsetTo<ClassDef>
michael@0: 		lookaheadClassDef;	/* Offset to glyph ClassDef table
michael@0: 					 * containing lookahead sequence
michael@0: 					 * data--from beginning of table */
michael@0:   OffsetArrayOf<ChainRuleSet>
michael@0: 		ruleSet;		/* Array of ChainRuleSet tables
michael@0: 					 * ordered by class */
michael@0:   public:
michael@0:   DEFINE_SIZE_ARRAY (12, ruleSet);
michael@0: };
michael@0: 
michael@0: struct ChainContextFormat3
michael@0: {
michael@0:   inline void closure (hb_closure_context_t *c) const
michael@0:   {
michael@0:     TRACE_CLOSURE (this);
michael@0:     const OffsetArrayOf<Coverage> &input = StructAfter<OffsetArrayOf<Coverage> > (backtrack);
michael@0: 
michael@0:     if (!(this+input[0]).intersects (c->glyphs))
michael@0:       return;
michael@0: 
michael@0:     const OffsetArrayOf<Coverage> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (input);
michael@0:     const ArrayOf<LookupRecord> &lookup = StructAfter<ArrayOf<LookupRecord> > (lookahead);
michael@0:     struct ChainContextClosureLookupContext lookup_context = {
michael@0:       {intersects_coverage},
michael@0:       {this, this, this}
michael@0:     };
michael@0:     chain_context_closure_lookup (c,
michael@0: 				  backtrack.len, (const USHORT *) backtrack.array,
michael@0: 				  input.len, (const USHORT *) input.array + 1,
michael@0: 				  lookahead.len, (const USHORT *) lookahead.array,
michael@0: 				  lookup.len, lookup.array,
michael@0: 				  lookup_context);
michael@0:   }
michael@0: 
michael@0:   inline void collect_glyphs (hb_collect_glyphs_context_t *c) const
michael@0:   {
michael@0:     TRACE_COLLECT_GLYPHS (this);
michael@0:     const OffsetArrayOf<Coverage> &input = StructAfter<OffsetArrayOf<Coverage> > (backtrack);
michael@0: 
michael@0:     (this+input[0]).add_coverage (c->input);
michael@0: 
michael@0:     const OffsetArrayOf<Coverage> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (input);
michael@0:     const ArrayOf<LookupRecord> &lookup = StructAfter<ArrayOf<LookupRecord> > (lookahead);
michael@0:     struct ChainContextCollectGlyphsLookupContext lookup_context = {
michael@0:       {collect_coverage},
michael@0:       {this, this, this}
michael@0:     };
michael@0:     chain_context_collect_glyphs_lookup (c,
michael@0: 					 backtrack.len, (const USHORT *) backtrack.array,
michael@0: 					 input.len, (const USHORT *) input.array + 1,
michael@0: 					 lookahead.len, (const USHORT *) lookahead.array,
michael@0: 					 lookup.len, lookup.array,
michael@0: 					 lookup_context);
michael@0:   }
michael@0: 
michael@0:   inline bool would_apply (hb_would_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_WOULD_APPLY (this);
michael@0: 
michael@0:     const OffsetArrayOf<Coverage> &input = StructAfter<OffsetArrayOf<Coverage> > (backtrack);
michael@0:     const OffsetArrayOf<Coverage> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (input);
michael@0:     const ArrayOf<LookupRecord> &lookup = StructAfter<ArrayOf<LookupRecord> > (lookahead);
michael@0:     struct ChainContextApplyLookupContext lookup_context = {
michael@0:       {match_coverage},
michael@0:       {this, this, this}
michael@0:     };
michael@0:     return TRACE_RETURN (chain_context_would_apply_lookup (c,
michael@0: 							   backtrack.len, (const USHORT *) backtrack.array,
michael@0: 							   input.len, (const USHORT *) input.array + 1,
michael@0: 							   lookahead.len, (const USHORT *) lookahead.array,
michael@0: 							   lookup.len, lookup.array, lookup_context));
michael@0:   }
michael@0: 
michael@0:   inline const Coverage &get_coverage (void) const
michael@0:   {
michael@0:     const OffsetArrayOf<Coverage> &input = StructAfter<OffsetArrayOf<Coverage> > (backtrack);
michael@0:     return this+input[0];
michael@0:   }
michael@0: 
michael@0:   inline bool apply (hb_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0:     const OffsetArrayOf<Coverage> &input = StructAfter<OffsetArrayOf<Coverage> > (backtrack);
michael@0: 
michael@0:     unsigned int index = (this+input[0]).get_coverage (c->buffer->cur().codepoint);
michael@0:     if (likely (index == NOT_COVERED)) return TRACE_RETURN (false);
michael@0: 
michael@0:     const OffsetArrayOf<Coverage> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (input);
michael@0:     const ArrayOf<LookupRecord> &lookup = StructAfter<ArrayOf<LookupRecord> > (lookahead);
michael@0:     struct ChainContextApplyLookupContext lookup_context = {
michael@0:       {match_coverage},
michael@0:       {this, this, this}
michael@0:     };
michael@0:     return TRACE_RETURN (chain_context_apply_lookup (c,
michael@0: 						     backtrack.len, (const USHORT *) backtrack.array,
michael@0: 						     input.len, (const USHORT *) input.array + 1,
michael@0: 						     lookahead.len, (const USHORT *) lookahead.array,
michael@0: 						     lookup.len, lookup.array, lookup_context));
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     if (!backtrack.sanitize (c, this)) return TRACE_RETURN (false);
michael@0:     OffsetArrayOf<Coverage> &input = StructAfter<OffsetArrayOf<Coverage> > (backtrack);
michael@0:     if (!input.sanitize (c, this)) return TRACE_RETURN (false);
michael@0:     OffsetArrayOf<Coverage> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (input);
michael@0:     if (!lookahead.sanitize (c, this)) return TRACE_RETURN (false);
michael@0:     ArrayOf<LookupRecord> &lookup = StructAfter<ArrayOf<LookupRecord> > (lookahead);
michael@0:     return TRACE_RETURN (lookup.sanitize (c));
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   USHORT	format;			/* Format identifier--format = 3 */
michael@0:   OffsetArrayOf<Coverage>
michael@0: 		backtrack;		/* Array of coverage tables
michael@0: 					 * in backtracking sequence, in  glyph
michael@0: 					 * sequence order */
michael@0:   OffsetArrayOf<Coverage>
michael@0: 		inputX		;	/* Array of coverage
michael@0: 					 * tables in input sequence, in glyph
michael@0: 					 * sequence order */
michael@0:   OffsetArrayOf<Coverage>
michael@0: 		lookaheadX;		/* Array of coverage tables
michael@0: 					 * in lookahead sequence, in glyph
michael@0: 					 * sequence order */
michael@0:   ArrayOf<LookupRecord>
michael@0: 		lookupX;		/* Array of LookupRecords--in
michael@0: 					 * design order) */
michael@0:   public:
michael@0:   DEFINE_SIZE_MIN (10);
michael@0: };
michael@0: 
michael@0: struct ChainContext
michael@0: {
michael@0:   template <typename context_t>
michael@0:   inline typename context_t::return_t dispatch (context_t *c) const
michael@0:   {
michael@0:     TRACE_DISPATCH (this);
michael@0:     switch (u.format) {
michael@0:     case 1: return TRACE_RETURN (c->dispatch (u.format1));
michael@0:     case 2: return TRACE_RETURN (c->dispatch (u.format2));
michael@0:     case 3: return TRACE_RETURN (c->dispatch (u.format3));
michael@0:     default:return TRACE_RETURN (c->default_return_value ());
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     if (!u.format.sanitize (c)) return TRACE_RETURN (false);
michael@0:     switch (u.format) {
michael@0:     case 1: return TRACE_RETURN (u.format1.sanitize (c));
michael@0:     case 2: return TRACE_RETURN (u.format2.sanitize (c));
michael@0:     case 3: return TRACE_RETURN (u.format3.sanitize (c));
michael@0:     default:return TRACE_RETURN (true);
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   union {
michael@0:   USHORT		format;	/* Format identifier */
michael@0:   ChainContextFormat1	format1;
michael@0:   ChainContextFormat2	format2;
michael@0:   ChainContextFormat3	format3;
michael@0:   } u;
michael@0: };
michael@0: 
michael@0: 
michael@0: struct ExtensionFormat1
michael@0: {
michael@0:   inline unsigned int get_type (void) const { return extensionLookupType; }
michael@0:   inline unsigned int get_offset (void) const { return extensionOffset; }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (c->check_struct (this));
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   USHORT	format;			/* Format identifier. Set to 1. */
michael@0:   USHORT	extensionLookupType;	/* Lookup type of subtable referenced
michael@0: 					 * by ExtensionOffset (i.e. the
michael@0: 					 * extension subtable). */
michael@0:   ULONG		extensionOffset;	/* Offset to the extension subtable,
michael@0: 					 * of lookup type subtable. */
michael@0:   public:
michael@0:   DEFINE_SIZE_STATIC (8);
michael@0: };
michael@0: 
michael@0: template <typename T>
michael@0: struct Extension
michael@0: {
michael@0:   inline unsigned int get_type (void) const
michael@0:   {
michael@0:     switch (u.format) {
michael@0:     case 1: return u.format1.get_type ();
michael@0:     default:return 0;
michael@0:     }
michael@0:   }
michael@0:   inline unsigned int get_offset (void) const
michael@0:   {
michael@0:     switch (u.format) {
michael@0:     case 1: return u.format1.get_offset ();
michael@0:     default:return 0;
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   template <typename X>
michael@0:   inline const X& get_subtable (void) const
michael@0:   {
michael@0:     unsigned int offset = get_offset ();
michael@0:     if (unlikely (!offset)) return Null(typename T::LookupSubTable);
michael@0:     return StructAtOffset<typename T::LookupSubTable> (this, offset);
michael@0:   }
michael@0: 
michael@0:   template <typename context_t>
michael@0:   inline typename context_t::return_t dispatch (context_t *c) const
michael@0:   {
michael@0:     return get_subtable<typename T::LookupSubTable> ().dispatch (c, get_type ());
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize_self (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     if (!u.format.sanitize (c)) return TRACE_RETURN (false);
michael@0:     switch (u.format) {
michael@0:     case 1: return TRACE_RETURN (u.format1.sanitize (c));
michael@0:     default:return TRACE_RETURN (true);
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     if (!sanitize_self (c)) return TRACE_RETURN (false);
michael@0:     unsigned int offset = get_offset ();
michael@0:     if (unlikely (!offset)) return TRACE_RETURN (true);
michael@0:     return TRACE_RETURN (StructAtOffset<typename T::LookupSubTable> (this, offset).sanitize (c, get_type ()));
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   union {
michael@0:   USHORT		format;		/* Format identifier */
michael@0:   ExtensionFormat1	format1;
michael@0:   } u;
michael@0: };
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * GSUB/GPOS Common
michael@0:  */
michael@0: 
michael@0: struct GSUBGPOS
michael@0: {
michael@0:   static const hb_tag_t GSUBTag	= HB_OT_TAG_GSUB;
michael@0:   static const hb_tag_t GPOSTag	= HB_OT_TAG_GPOS;
michael@0: 
michael@0:   inline unsigned int get_script_count (void) const
michael@0:   { return (this+scriptList).len; }
michael@0:   inline const Tag& get_script_tag (unsigned int i) const
michael@0:   { return (this+scriptList).get_tag (i); }
michael@0:   inline unsigned int get_script_tags (unsigned int start_offset,
michael@0: 				       unsigned int *script_count /* IN/OUT */,
michael@0: 				       hb_tag_t     *script_tags /* OUT */) const
michael@0:   { return (this+scriptList).get_tags (start_offset, script_count, script_tags); }
michael@0:   inline const Script& get_script (unsigned int i) const
michael@0:   { return (this+scriptList)[i]; }
michael@0:   inline bool find_script_index (hb_tag_t tag, unsigned int *index) const
michael@0:   { return (this+scriptList).find_index (tag, index); }
michael@0: 
michael@0:   inline unsigned int get_feature_count (void) const
michael@0:   { return (this+featureList).len; }
michael@0:   inline const Tag& get_feature_tag (unsigned int i) const
michael@0:   { return (this+featureList).get_tag (i); }
michael@0:   inline unsigned int get_feature_tags (unsigned int start_offset,
michael@0: 					unsigned int *feature_count /* IN/OUT */,
michael@0: 					hb_tag_t     *feature_tags /* OUT */) const
michael@0:   { return (this+featureList).get_tags (start_offset, feature_count, feature_tags); }
michael@0:   inline const Feature& get_feature (unsigned int i) const
michael@0:   { return (this+featureList)[i]; }
michael@0:   inline bool find_feature_index (hb_tag_t tag, unsigned int *index) const
michael@0:   { return (this+featureList).find_index (tag, index); }
michael@0: 
michael@0:   inline unsigned int get_lookup_count (void) const
michael@0:   { return (this+lookupList).len; }
michael@0:   inline const Lookup& get_lookup (unsigned int i) const
michael@0:   { return (this+lookupList)[i]; }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (version.sanitize (c) && likely (version.major == 1) &&
michael@0: 			 scriptList.sanitize (c, this) &&
michael@0: 			 featureList.sanitize (c, this) &&
michael@0: 			 lookupList.sanitize (c, this));
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   FixedVersion	version;	/* Version of the GSUB/GPOS table--initially set
michael@0: 				 * to 0x00010000 */
michael@0:   OffsetTo<ScriptList>
michael@0: 		scriptList;  	/* ScriptList table */
michael@0:   OffsetTo<FeatureList>
michael@0: 		featureList; 	/* FeatureList table */
michael@0:   OffsetTo<LookupList>
michael@0: 		lookupList; 	/* LookupList table */
michael@0:   public:
michael@0:   DEFINE_SIZE_STATIC (10);
michael@0: };
michael@0: 
michael@0: 
michael@0: } /* namespace OT */
michael@0: 
michael@0: 
michael@0: #endif /* HB_OT_LAYOUT_GSUBGPOS_PRIVATE_HH */