michael@0: /*
michael@0:  * Copyright © 2007,2008,2009,2010  Red Hat, Inc.
michael@0:  * Copyright © 2010,2012,2013  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_GSUB_TABLE_HH
michael@0: #define HB_OT_LAYOUT_GSUB_TABLE_HH
michael@0: 
michael@0: #include "hb-ot-layout-gsubgpos-private.hh"
michael@0: 
michael@0: 
michael@0: namespace OT {
michael@0: 
michael@0: 
michael@0: struct SingleSubstFormat1
michael@0: {
michael@0:   inline void closure (hb_closure_context_t *c) const
michael@0:   {
michael@0:     TRACE_CLOSURE (this);
michael@0:     Coverage::Iter iter;
michael@0:     for (iter.init (this+coverage); iter.more (); iter.next ()) {
michael@0:       hb_codepoint_t glyph_id = iter.get_glyph ();
michael@0:       if (c->glyphs->has (glyph_id))
michael@0: 	c->glyphs->add ((glyph_id + deltaGlyphID) & 0xFFFF);
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:     Coverage::Iter iter;
michael@0:     for (iter.init (this+coverage); iter.more (); iter.next ()) {
michael@0:       hb_codepoint_t glyph_id = iter.get_glyph ();
michael@0:       c->input->add (glyph_id);
michael@0:       c->output->add ((glyph_id + deltaGlyphID) & 0xFFFF);
michael@0:     }
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 would_apply (hb_would_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_WOULD_APPLY (this);
michael@0:     return TRACE_RETURN (c->len == 1 && (this+coverage).get_coverage (c->glyphs[0]) != NOT_COVERED);
michael@0:   }
michael@0: 
michael@0:   inline bool apply (hb_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0:     hb_codepoint_t glyph_id = c->buffer->cur().codepoint;
michael@0:     unsigned int index = (this+coverage).get_coverage (glyph_id);
michael@0:     if (likely (index == NOT_COVERED)) return TRACE_RETURN (false);
michael@0: 
michael@0:     /* According to the Adobe Annotated OpenType Suite, result is always
michael@0:      * limited to 16bit. */
michael@0:     glyph_id = (glyph_id + deltaGlyphID) & 0xFFFF;
michael@0:     c->replace_glyph (glyph_id);
michael@0: 
michael@0:     return TRACE_RETURN (true);
michael@0:   }
michael@0: 
michael@0:   inline bool serialize (hb_serialize_context_t *c,
michael@0: 			 Supplier<GlyphID> &glyphs,
michael@0: 			 unsigned int num_glyphs,
michael@0: 			 int delta)
michael@0:   {
michael@0:     TRACE_SERIALIZE (this);
michael@0:     if (unlikely (!c->extend_min (*this))) return TRACE_RETURN (false);
michael@0:     if (unlikely (!coverage.serialize (c, this).serialize (c, glyphs, num_glyphs))) return TRACE_RETURN (false);
michael@0:     deltaGlyphID.set (delta); /* TODO(serilaize) overflow? */
michael@0:     return TRACE_RETURN (true);
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) && deltaGlyphID.sanitize (c));
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 Substitution table */
michael@0:   SHORT		deltaGlyphID;		/* Add to original GlyphID to get
michael@0: 					 * substitute GlyphID */
michael@0:   public:
michael@0:   DEFINE_SIZE_STATIC (6);
michael@0: };
michael@0: 
michael@0: struct SingleSubstFormat2
michael@0: {
michael@0:   inline void closure (hb_closure_context_t *c) const
michael@0:   {
michael@0:     TRACE_CLOSURE (this);
michael@0:     Coverage::Iter iter;
michael@0:     for (iter.init (this+coverage); iter.more (); iter.next ()) {
michael@0:       if (c->glyphs->has (iter.get_glyph ()))
michael@0: 	c->glyphs->add (substitute[iter.get_coverage ()]);
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:     Coverage::Iter iter;
michael@0:     for (iter.init (this+coverage); iter.more (); iter.next ()) {
michael@0:       c->input->add (iter.get_glyph ());
michael@0:       c->output->add (substitute[iter.get_coverage ()]);
michael@0:     }
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 would_apply (hb_would_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_WOULD_APPLY (this);
michael@0:     return TRACE_RETURN (c->len == 1 && (this+coverage).get_coverage (c->glyphs[0]) != NOT_COVERED);
michael@0:   }
michael@0: 
michael@0:   inline bool apply (hb_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0:     hb_codepoint_t glyph_id = c->buffer->cur().codepoint;
michael@0:     unsigned int index = (this+coverage).get_coverage (glyph_id);
michael@0:     if (likely (index == NOT_COVERED)) return TRACE_RETURN (false);
michael@0: 
michael@0:     if (unlikely (index >= substitute.len)) return TRACE_RETURN (false);
michael@0: 
michael@0:     glyph_id = substitute[index];
michael@0:     c->replace_glyph (glyph_id);
michael@0: 
michael@0:     return TRACE_RETURN (true);
michael@0:   }
michael@0: 
michael@0:   inline bool serialize (hb_serialize_context_t *c,
michael@0: 			 Supplier<GlyphID> &glyphs,
michael@0: 			 Supplier<GlyphID> &substitutes,
michael@0: 			 unsigned int num_glyphs)
michael@0:   {
michael@0:     TRACE_SERIALIZE (this);
michael@0:     if (unlikely (!c->extend_min (*this))) return TRACE_RETURN (false);
michael@0:     if (unlikely (!substitute.serialize (c, substitutes, num_glyphs))) return TRACE_RETURN (false);
michael@0:     if (unlikely (!coverage.serialize (c, this).serialize (c, glyphs, num_glyphs))) return TRACE_RETURN (false);
michael@0:     return TRACE_RETURN (true);
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) && substitute.sanitize (c));
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 Substitution table */
michael@0:   ArrayOf<GlyphID>
michael@0: 		substitute;		/* Array of substitute
michael@0: 					 * GlyphIDs--ordered by Coverage Index */
michael@0:   public:
michael@0:   DEFINE_SIZE_ARRAY (6, substitute);
michael@0: };
michael@0: 
michael@0: struct SingleSubst
michael@0: {
michael@0:   inline bool serialize (hb_serialize_context_t *c,
michael@0: 			 Supplier<GlyphID> &glyphs,
michael@0: 			 Supplier<GlyphID> &substitutes,
michael@0: 			 unsigned int num_glyphs)
michael@0:   {
michael@0:     TRACE_SERIALIZE (this);
michael@0:     if (unlikely (!c->extend_min (u.format))) return TRACE_RETURN (false);
michael@0:     unsigned int format = 2;
michael@0:     int delta;
michael@0:     if (num_glyphs) {
michael@0:       format = 1;
michael@0:       /* TODO(serialize) check for wrap-around */
michael@0:       delta = substitutes[0] - glyphs[0];
michael@0:       for (unsigned int i = 1; i < num_glyphs; i++)
michael@0: 	if (delta != substitutes[i] - glyphs[i]) {
michael@0: 	  format = 2;
michael@0: 	  break;
michael@0: 	}
michael@0:     }
michael@0:     u.format.set (format);
michael@0:     switch (u.format) {
michael@0:     case 1: return TRACE_RETURN (u.format1.serialize (c, glyphs, num_glyphs, delta));
michael@0:     case 2: return TRACE_RETURN (u.format2.serialize (c, glyphs, substitutes, num_glyphs));
michael@0:     default:return TRACE_RETURN (false);
michael@0:     }
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:     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:     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:     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:   SingleSubstFormat1	format1;
michael@0:   SingleSubstFormat2	format2;
michael@0:   } u;
michael@0: };
michael@0: 
michael@0: 
michael@0: struct Sequence
michael@0: {
michael@0:   inline void closure (hb_closure_context_t *c) const
michael@0:   {
michael@0:     TRACE_CLOSURE (this);
michael@0:     unsigned int count = substitute.len;
michael@0:     for (unsigned int i = 0; i < count; i++)
michael@0:       c->glyphs->add (substitute[i]);
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:     unsigned int count = substitute.len;
michael@0:     for (unsigned int i = 0; i < count; i++)
michael@0:       c->output->add (substitute[i]);
michael@0:   }
michael@0: 
michael@0:   inline bool apply (hb_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0:     if (unlikely (!substitute.len)) return TRACE_RETURN (false);
michael@0: 
michael@0:     unsigned int klass = _hb_glyph_info_is_ligature (&c->buffer->cur()) ?
michael@0: 			 HB_OT_LAYOUT_GLYPH_PROPS_BASE_GLYPH : 0;
michael@0:     unsigned int count = substitute.len;
michael@0:     if (count == 1) /* Special-case to make it in-place. */
michael@0:     {
michael@0:       c->replace_glyph (substitute.array[0]);
michael@0:     }
michael@0:     else
michael@0:     {
michael@0:       for (unsigned int i = 0; i < count; i++) {
michael@0: 	_hb_glyph_info_set_lig_props_for_component (&c->buffer->cur(), i);
michael@0: 	c->output_glyph (substitute.array[i], klass);
michael@0:       }
michael@0:       c->buffer->skip_glyph ();
michael@0:     }
michael@0: 
michael@0:     return TRACE_RETURN (true);
michael@0:   }
michael@0: 
michael@0:   inline bool serialize (hb_serialize_context_t *c,
michael@0: 			 Supplier<GlyphID> &glyphs,
michael@0: 			 unsigned int num_glyphs)
michael@0:   {
michael@0:     TRACE_SERIALIZE (this);
michael@0:     if (unlikely (!c->extend_min (*this))) return TRACE_RETURN (false);
michael@0:     if (unlikely (!substitute.serialize (c, glyphs, num_glyphs))) return TRACE_RETURN (false);
michael@0:     return TRACE_RETURN (true);
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (substitute.sanitize (c));
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   ArrayOf<GlyphID>
michael@0: 		substitute;		/* String of GlyphIDs to substitute */
michael@0:   public:
michael@0:   DEFINE_SIZE_ARRAY (2, substitute);
michael@0: };
michael@0: 
michael@0: struct MultipleSubstFormat1
michael@0: {
michael@0:   inline void closure (hb_closure_context_t *c) const
michael@0:   {
michael@0:     TRACE_CLOSURE (this);
michael@0:     Coverage::Iter iter;
michael@0:     for (iter.init (this+coverage); iter.more (); iter.next ()) {
michael@0:       if (c->glyphs->has (iter.get_glyph ()))
michael@0: 	(this+sequence[iter.get_coverage ()]).closure (c);
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:     unsigned int count = sequence.len;
michael@0:     for (unsigned int i = 0; i < count; i++)
michael@0: 	(this+sequence[i]).collect_glyphs (c);
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 would_apply (hb_would_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_WOULD_APPLY (this);
michael@0:     return TRACE_RETURN (c->len == 1 && (this+coverage).get_coverage (c->glyphs[0]) != NOT_COVERED);
michael@0:   }
michael@0: 
michael@0:   inline bool apply (hb_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0: 
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:     return TRACE_RETURN ((this+sequence[index]).apply (c));
michael@0:   }
michael@0: 
michael@0:   inline bool serialize (hb_serialize_context_t *c,
michael@0: 			 Supplier<GlyphID> &glyphs,
michael@0: 			 Supplier<unsigned int> &substitute_len_list,
michael@0: 			 unsigned int num_glyphs,
michael@0: 			 Supplier<GlyphID> &substitute_glyphs_list)
michael@0:   {
michael@0:     TRACE_SERIALIZE (this);
michael@0:     if (unlikely (!c->extend_min (*this))) return TRACE_RETURN (false);
michael@0:     if (unlikely (!sequence.serialize (c, num_glyphs))) return TRACE_RETURN (false);
michael@0:     for (unsigned int i = 0; i < num_glyphs; i++)
michael@0:       if (unlikely (!sequence[i].serialize (c, this).serialize (c,
michael@0: 								substitute_glyphs_list,
michael@0: 								substitute_len_list[i]))) return TRACE_RETURN (false);
michael@0:     substitute_len_list.advance (num_glyphs);
michael@0:     if (unlikely (!coverage.serialize (c, this).serialize (c, glyphs, num_glyphs))) return TRACE_RETURN (false);
michael@0:     return TRACE_RETURN (true);
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) && sequence.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 Substitution table */
michael@0:   OffsetArrayOf<Sequence>
michael@0: 		sequence;		/* Array of Sequence tables
michael@0: 					 * ordered by Coverage Index */
michael@0:   public:
michael@0:   DEFINE_SIZE_ARRAY (6, sequence);
michael@0: };
michael@0: 
michael@0: struct MultipleSubst
michael@0: {
michael@0:   inline bool serialize (hb_serialize_context_t *c,
michael@0: 			 Supplier<GlyphID> &glyphs,
michael@0: 			 Supplier<unsigned int> &substitute_len_list,
michael@0: 			 unsigned int num_glyphs,
michael@0: 			 Supplier<GlyphID> &substitute_glyphs_list)
michael@0:   {
michael@0:     TRACE_SERIALIZE (this);
michael@0:     if (unlikely (!c->extend_min (u.format))) return TRACE_RETURN (false);
michael@0:     unsigned int format = 1;
michael@0:     u.format.set (format);
michael@0:     switch (u.format) {
michael@0:     case 1: return TRACE_RETURN (u.format1.serialize (c, glyphs, substitute_len_list, num_glyphs, substitute_glyphs_list));
michael@0:     default:return TRACE_RETURN (false);
michael@0:     }
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:     TRACE_DISPATCH (this);
michael@0:     switch (u.format) {
michael@0:     case 1: return TRACE_RETURN (c->dispatch (u.format1));
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:     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:   MultipleSubstFormat1	format1;
michael@0:   } u;
michael@0: };
michael@0: 
michael@0: 
michael@0: typedef ArrayOf<GlyphID> AlternateSet;	/* Array of alternate GlyphIDs--in
michael@0: 					 * arbitrary order */
michael@0: 
michael@0: struct AlternateSubstFormat1
michael@0: {
michael@0:   inline void closure (hb_closure_context_t *c) const
michael@0:   {
michael@0:     TRACE_CLOSURE (this);
michael@0:     Coverage::Iter iter;
michael@0:     for (iter.init (this+coverage); iter.more (); iter.next ()) {
michael@0:       if (c->glyphs->has (iter.get_glyph ())) {
michael@0: 	const AlternateSet &alt_set = this+alternateSet[iter.get_coverage ()];
michael@0: 	unsigned int count = alt_set.len;
michael@0: 	for (unsigned int i = 0; i < count; i++)
michael@0: 	  c->glyphs->add (alt_set[i]);
michael@0:       }
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:     Coverage::Iter iter;
michael@0:     for (iter.init (this+coverage); iter.more (); iter.next ()) {
michael@0:       c->input->add (iter.get_glyph ());
michael@0:       const AlternateSet &alt_set = this+alternateSet[iter.get_coverage ()];
michael@0:       unsigned int count = alt_set.len;
michael@0:       for (unsigned int i = 0; i < count; i++)
michael@0: 	c->output->add (alt_set[i]);
michael@0:     }
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 would_apply (hb_would_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_WOULD_APPLY (this);
michael@0:     return TRACE_RETURN (c->len == 1 && (this+coverage).get_coverage (c->glyphs[0]) != NOT_COVERED);
michael@0:   }
michael@0: 
michael@0:   inline bool apply (hb_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0:     hb_codepoint_t glyph_id = c->buffer->cur().codepoint;
michael@0: 
michael@0:     unsigned int index = (this+coverage).get_coverage (glyph_id);
michael@0:     if (likely (index == NOT_COVERED)) return TRACE_RETURN (false);
michael@0: 
michael@0:     const AlternateSet &alt_set = this+alternateSet[index];
michael@0: 
michael@0:     if (unlikely (!alt_set.len)) return TRACE_RETURN (false);
michael@0: 
michael@0:     hb_mask_t glyph_mask = c->buffer->cur().mask;
michael@0:     hb_mask_t lookup_mask = c->lookup_mask;
michael@0: 
michael@0:     /* Note: This breaks badly if two features enabled this lookup together. */
michael@0:     unsigned int shift = _hb_ctz (lookup_mask);
michael@0:     unsigned int alt_index = ((lookup_mask & glyph_mask) >> shift);
michael@0: 
michael@0:     if (unlikely (alt_index > alt_set.len || alt_index == 0)) return TRACE_RETURN (false);
michael@0: 
michael@0:     glyph_id = alt_set[alt_index - 1];
michael@0: 
michael@0:     c->replace_glyph (glyph_id);
michael@0: 
michael@0:     return TRACE_RETURN (true);
michael@0:   }
michael@0: 
michael@0:   inline bool serialize (hb_serialize_context_t *c,
michael@0: 			 Supplier<GlyphID> &glyphs,
michael@0: 			 Supplier<unsigned int> &alternate_len_list,
michael@0: 			 unsigned int num_glyphs,
michael@0: 			 Supplier<GlyphID> &alternate_glyphs_list)
michael@0:   {
michael@0:     TRACE_SERIALIZE (this);
michael@0:     if (unlikely (!c->extend_min (*this))) return TRACE_RETURN (false);
michael@0:     if (unlikely (!alternateSet.serialize (c, num_glyphs))) return TRACE_RETURN (false);
michael@0:     for (unsigned int i = 0; i < num_glyphs; i++)
michael@0:       if (unlikely (!alternateSet[i].serialize (c, this).serialize (c,
michael@0: 								    alternate_glyphs_list,
michael@0: 								    alternate_len_list[i]))) return TRACE_RETURN (false);
michael@0:     alternate_len_list.advance (num_glyphs);
michael@0:     if (unlikely (!coverage.serialize (c, this).serialize (c, glyphs, num_glyphs))) return TRACE_RETURN (false);
michael@0:     return TRACE_RETURN (true);
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) && alternateSet.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 Substitution table */
michael@0:   OffsetArrayOf<AlternateSet>
michael@0: 		alternateSet;		/* Array of AlternateSet tables
michael@0: 					 * ordered by Coverage Index */
michael@0:   public:
michael@0:   DEFINE_SIZE_ARRAY (6, alternateSet);
michael@0: };
michael@0: 
michael@0: struct AlternateSubst
michael@0: {
michael@0:   inline bool serialize (hb_serialize_context_t *c,
michael@0: 			 Supplier<GlyphID> &glyphs,
michael@0: 			 Supplier<unsigned int> &alternate_len_list,
michael@0: 			 unsigned int num_glyphs,
michael@0: 			 Supplier<GlyphID> &alternate_glyphs_list)
michael@0:   {
michael@0:     TRACE_SERIALIZE (this);
michael@0:     if (unlikely (!c->extend_min (u.format))) return TRACE_RETURN (false);
michael@0:     unsigned int format = 1;
michael@0:     u.format.set (format);
michael@0:     switch (u.format) {
michael@0:     case 1: return TRACE_RETURN (u.format1.serialize (c, glyphs, alternate_len_list, num_glyphs, alternate_glyphs_list));
michael@0:     default:return TRACE_RETURN (false);
michael@0:     }
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:     TRACE_DISPATCH (this);
michael@0:     switch (u.format) {
michael@0:     case 1: return TRACE_RETURN (c->dispatch (u.format1));
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:     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:   AlternateSubstFormat1	format1;
michael@0:   } u;
michael@0: };
michael@0: 
michael@0: 
michael@0: struct Ligature
michael@0: {
michael@0:   inline void closure (hb_closure_context_t *c) const
michael@0:   {
michael@0:     TRACE_CLOSURE (this);
michael@0:     unsigned int count = component.len;
michael@0:     for (unsigned int i = 1; i < count; i++)
michael@0:       if (!c->glyphs->has (component[i]))
michael@0:         return;
michael@0:     c->glyphs->add (ligGlyph);
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:     unsigned int count = component.len;
michael@0:     for (unsigned int i = 1; i < count; i++)
michael@0:       c->input->add (component[i]);
michael@0:     c->output->add (ligGlyph);
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:     if (c->len != component.len)
michael@0:       return TRACE_RETURN (false);
michael@0: 
michael@0:     for (unsigned int i = 1; i < c->len; i++)
michael@0:       if (likely (c->glyphs[i] != component[i]))
michael@0: 	return TRACE_RETURN (false);
michael@0: 
michael@0:     return TRACE_RETURN (true);
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 count = component.len;
michael@0:     if (unlikely (count < 1)) return TRACE_RETURN (false);
michael@0: 
michael@0:     bool is_mark_ligature = false;
michael@0:     unsigned int total_component_count = 0;
michael@0: 
michael@0:     unsigned int match_length = 0;
michael@0:     unsigned int match_positions[MAX_CONTEXT_LENGTH];
michael@0: 
michael@0:     if (likely (!match_input (c, count,
michael@0: 			      &component[1],
michael@0: 			      match_glyph,
michael@0: 			      NULL,
michael@0: 			      &match_length,
michael@0: 			      match_positions,
michael@0: 			      &is_mark_ligature,
michael@0: 			      &total_component_count)))
michael@0:       return TRACE_RETURN (false);
michael@0: 
michael@0:     ligate_input (c,
michael@0: 		  count,
michael@0: 		  match_positions,
michael@0: 		  match_length,
michael@0: 		  ligGlyph,
michael@0: 		  is_mark_ligature,
michael@0: 		  total_component_count);
michael@0: 
michael@0:     return TRACE_RETURN (true);
michael@0:   }
michael@0: 
michael@0:   inline bool serialize (hb_serialize_context_t *c,
michael@0: 			 GlyphID ligature,
michael@0: 			 Supplier<GlyphID> &components, /* Starting from second */
michael@0: 			 unsigned int num_components /* Including first component */)
michael@0:   {
michael@0:     TRACE_SERIALIZE (this);
michael@0:     if (unlikely (!c->extend_min (*this))) return TRACE_RETURN (false);
michael@0:     ligGlyph = ligature;
michael@0:     if (unlikely (!component.serialize (c, components, num_components))) return TRACE_RETURN (false);
michael@0:     return TRACE_RETURN (true);
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 TRACE_RETURN (ligGlyph.sanitize (c) && component.sanitize (c));
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   GlyphID	ligGlyph;		/* GlyphID of ligature to substitute */
michael@0:   HeadlessArrayOf<GlyphID>
michael@0: 		component;		/* Array of component GlyphIDs--start
michael@0: 					 * with the second  component--ordered
michael@0: 					 * in writing direction */
michael@0:   public:
michael@0:   DEFINE_SIZE_ARRAY (4, component);
michael@0: };
michael@0: 
michael@0: struct LigatureSet
michael@0: {
michael@0:   inline void closure (hb_closure_context_t *c) const
michael@0:   {
michael@0:     TRACE_CLOSURE (this);
michael@0:     unsigned int num_ligs = ligature.len;
michael@0:     for (unsigned int i = 0; i < num_ligs; i++)
michael@0:       (this+ligature[i]).closure (c);
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:     unsigned int num_ligs = ligature.len;
michael@0:     for (unsigned int i = 0; i < num_ligs; i++)
michael@0:       (this+ligature[i]).collect_glyphs (c);
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:     unsigned int num_ligs = ligature.len;
michael@0:     for (unsigned int i = 0; i < num_ligs; i++)
michael@0:     {
michael@0:       const Ligature &lig = this+ligature[i];
michael@0:       if (lig.would_apply (c))
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) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0:     unsigned int num_ligs = ligature.len;
michael@0:     for (unsigned int i = 0; i < num_ligs; i++)
michael@0:     {
michael@0:       const Ligature &lig = this+ligature[i];
michael@0:       if (lig.apply (c)) return TRACE_RETURN (true);
michael@0:     }
michael@0: 
michael@0:     return TRACE_RETURN (false);
michael@0:   }
michael@0: 
michael@0:   inline bool serialize (hb_serialize_context_t *c,
michael@0: 			 Supplier<GlyphID> &ligatures,
michael@0: 			 Supplier<unsigned int> &component_count_list,
michael@0: 			 unsigned int num_ligatures,
michael@0: 			 Supplier<GlyphID> &component_list /* Starting from second for each ligature */)
michael@0:   {
michael@0:     TRACE_SERIALIZE (this);
michael@0:     if (unlikely (!c->extend_min (*this))) return TRACE_RETURN (false);
michael@0:     if (unlikely (!ligature.serialize (c, num_ligatures))) return TRACE_RETURN (false);
michael@0:     for (unsigned int i = 0; i < num_ligatures; i++)
michael@0:       if (unlikely (!ligature[i].serialize (c, this).serialize (c,
michael@0: 								ligatures[i],
michael@0: 								component_list,
michael@0: 								component_count_list[i]))) return TRACE_RETURN (false);
michael@0:     ligatures.advance (num_ligatures);
michael@0:     component_count_list.advance (num_ligatures);
michael@0:     return TRACE_RETURN (true);
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (ligature.sanitize (c, this));
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   OffsetArrayOf<Ligature>
michael@0: 		ligature;		/* Array LigatureSet tables
michael@0: 					 * ordered by preference */
michael@0:   public:
michael@0:   DEFINE_SIZE_ARRAY (2, ligature);
michael@0: };
michael@0: 
michael@0: struct LigatureSubstFormat1
michael@0: {
michael@0:   inline void closure (hb_closure_context_t *c) const
michael@0:   {
michael@0:     TRACE_CLOSURE (this);
michael@0:     Coverage::Iter iter;
michael@0:     for (iter.init (this+coverage); iter.more (); iter.next ()) {
michael@0:       if (c->glyphs->has (iter.get_glyph ()))
michael@0: 	(this+ligatureSet[iter.get_coverage ()]).closure (c);
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:     Coverage::Iter iter;
michael@0:     for (iter.init (this+coverage); iter.more (); iter.next ()) {
michael@0:       c->input->add (iter.get_glyph ());
michael@0:       (this+ligatureSet[iter.get_coverage ()]).collect_glyphs (c);
michael@0:     }
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 would_apply (hb_would_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_WOULD_APPLY (this);
michael@0:     unsigned int index = (this+coverage).get_coverage (c->glyphs[0]);
michael@0:     if (likely (index == NOT_COVERED)) return TRACE_RETURN (false);
michael@0: 
michael@0:     const LigatureSet &lig_set = this+ligatureSet[index];
michael@0:     return TRACE_RETURN (lig_set.would_apply (c));
michael@0:   }
michael@0: 
michael@0:   inline bool apply (hb_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0:     hb_codepoint_t glyph_id = c->buffer->cur().codepoint;
michael@0: 
michael@0:     unsigned int index = (this+coverage).get_coverage (glyph_id);
michael@0:     if (likely (index == NOT_COVERED)) return TRACE_RETURN (false);
michael@0: 
michael@0:     const LigatureSet &lig_set = this+ligatureSet[index];
michael@0:     return TRACE_RETURN (lig_set.apply (c));
michael@0:   }
michael@0: 
michael@0:   inline bool serialize (hb_serialize_context_t *c,
michael@0: 			 Supplier<GlyphID> &first_glyphs,
michael@0: 			 Supplier<unsigned int> &ligature_per_first_glyph_count_list,
michael@0: 			 unsigned int num_first_glyphs,
michael@0: 			 Supplier<GlyphID> &ligatures_list,
michael@0: 			 Supplier<unsigned int> &component_count_list,
michael@0: 			 Supplier<GlyphID> &component_list /* Starting from second for each ligature */)
michael@0:   {
michael@0:     TRACE_SERIALIZE (this);
michael@0:     if (unlikely (!c->extend_min (*this))) return TRACE_RETURN (false);
michael@0:     if (unlikely (!ligatureSet.serialize (c, num_first_glyphs))) return TRACE_RETURN (false);
michael@0:     for (unsigned int i = 0; i < num_first_glyphs; i++)
michael@0:       if (unlikely (!ligatureSet[i].serialize (c, this).serialize (c,
michael@0: 								   ligatures_list,
michael@0: 								   component_count_list,
michael@0: 								   ligature_per_first_glyph_count_list[i],
michael@0: 								   component_list))) return TRACE_RETURN (false);
michael@0:     ligature_per_first_glyph_count_list.advance (num_first_glyphs);
michael@0:     if (unlikely (!coverage.serialize (c, this).serialize (c, first_glyphs, num_first_glyphs))) return TRACE_RETURN (false);
michael@0:     return TRACE_RETURN (true);
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) && ligatureSet.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 Substitution table */
michael@0:   OffsetArrayOf<LigatureSet>
michael@0: 		ligatureSet;		/* Array LigatureSet tables
michael@0: 					 * ordered by Coverage Index */
michael@0:   public:
michael@0:   DEFINE_SIZE_ARRAY (6, ligatureSet);
michael@0: };
michael@0: 
michael@0: struct LigatureSubst
michael@0: {
michael@0:   inline bool serialize (hb_serialize_context_t *c,
michael@0: 			 Supplier<GlyphID> &first_glyphs,
michael@0: 			 Supplier<unsigned int> &ligature_per_first_glyph_count_list,
michael@0: 			 unsigned int num_first_glyphs,
michael@0: 			 Supplier<GlyphID> &ligatures_list,
michael@0: 			 Supplier<unsigned int> &component_count_list,
michael@0: 			 Supplier<GlyphID> &component_list /* Starting from second for each ligature */)
michael@0:   {
michael@0:     TRACE_SERIALIZE (this);
michael@0:     if (unlikely (!c->extend_min (u.format))) return TRACE_RETURN (false);
michael@0:     unsigned int format = 1;
michael@0:     u.format.set (format);
michael@0:     switch (u.format) {
michael@0:     case 1: return TRACE_RETURN (u.format1.serialize (c, first_glyphs, ligature_per_first_glyph_count_list, num_first_glyphs,
michael@0: 						      ligatures_list, component_count_list, component_list));
michael@0:     default:return TRACE_RETURN (false);
michael@0:     }
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:     TRACE_DISPATCH (this);
michael@0:     switch (u.format) {
michael@0:     case 1: return TRACE_RETURN (c->dispatch (u.format1));
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:     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:   LigatureSubstFormat1	format1;
michael@0:   } u;
michael@0: };
michael@0: 
michael@0: 
michael@0: struct ContextSubst : Context {};
michael@0: 
michael@0: struct ChainContextSubst : ChainContext {};
michael@0: 
michael@0: struct ExtensionSubst : Extension<ExtensionSubst>
michael@0: {
michael@0:   typedef struct SubstLookupSubTable LookupSubTable;
michael@0: 
michael@0:   inline bool is_reverse (void) const;
michael@0: };
michael@0: 
michael@0: 
michael@0: struct ReverseChainSingleSubstFormat1
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> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (backtrack);
michael@0: 
michael@0:     unsigned int count;
michael@0: 
michael@0:     count = backtrack.len;
michael@0:     for (unsigned int i = 0; i < count; i++)
michael@0:       if (!(this+backtrack[i]).intersects (c->glyphs))
michael@0:         return;
michael@0: 
michael@0:     count = lookahead.len;
michael@0:     for (unsigned int i = 0; i < count; i++)
michael@0:       if (!(this+lookahead[i]).intersects (c->glyphs))
michael@0:         return;
michael@0: 
michael@0:     const ArrayOf<GlyphID> &substitute = StructAfter<ArrayOf<GlyphID> > (lookahead);
michael@0:     Coverage::Iter iter;
michael@0:     for (iter.init (this+coverage); iter.more (); iter.next ()) {
michael@0:       if (c->glyphs->has (iter.get_glyph ()))
michael@0: 	c->glyphs->add (substitute[iter.get_coverage ()]);
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: 
michael@0:     const OffsetArrayOf<Coverage> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (backtrack);
michael@0: 
michael@0:     unsigned int count;
michael@0: 
michael@0:     (this+coverage).add_coverage (c->input);
michael@0: 
michael@0:     count = backtrack.len;
michael@0:     for (unsigned int i = 0; i < count; i++)
michael@0:       (this+backtrack[i]).add_coverage (c->before);
michael@0: 
michael@0:     count = lookahead.len;
michael@0:     for (unsigned int i = 0; i < count; i++)
michael@0:       (this+lookahead[i]).add_coverage (c->after);
michael@0: 
michael@0:     const ArrayOf<GlyphID> &substitute = StructAfter<ArrayOf<GlyphID> > (lookahead);
michael@0:     count = substitute.len;
michael@0:     for (unsigned int i = 0; i < count; i++)
michael@0:       c->output->add (substitute[i]);
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 would_apply (hb_would_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_WOULD_APPLY (this);
michael@0:     return TRACE_RETURN (c->len == 1 && (this+coverage).get_coverage (c->glyphs[0]) != NOT_COVERED);
michael@0:   }
michael@0: 
michael@0:   inline bool apply (hb_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0:     if (unlikely (c->nesting_level_left != MAX_NESTING_LEVEL))
michael@0:       return TRACE_RETURN (false); /* No chaining to this type */
michael@0: 
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 OffsetArrayOf<Coverage> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (backtrack);
michael@0:     const ArrayOf<GlyphID> &substitute = StructAfter<ArrayOf<GlyphID> > (lookahead);
michael@0: 
michael@0:     if (match_backtrack (c,
michael@0: 			 backtrack.len, (USHORT *) backtrack.array,
michael@0: 			 match_coverage, this) &&
michael@0:         match_lookahead (c,
michael@0: 			 lookahead.len, (USHORT *) lookahead.array,
michael@0: 			 match_coverage, this,
michael@0: 			 1))
michael@0:     {
michael@0:       c->replace_glyph_inplace (substitute[index]);
michael@0:       /* Note: We DON'T decrease buffer->idx.  The main loop does it
michael@0:        * for us.  This is useful for preventing surprises if someone
michael@0:        * calls us through a Context lookup. */
michael@0:       return TRACE_RETURN (true);
michael@0:     }
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:     if (!(coverage.sanitize (c, this) && backtrack.sanitize (c, this)))
michael@0:       return TRACE_RETURN (false);
michael@0:     OffsetArrayOf<Coverage> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (backtrack);
michael@0:     if (!lookahead.sanitize (c, this))
michael@0:       return TRACE_RETURN (false);
michael@0:     ArrayOf<GlyphID> &substitute = StructAfter<ArrayOf<GlyphID> > (lookahead);
michael@0:     return TRACE_RETURN (substitute.sanitize (c));
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<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: 		lookaheadX;		/* Array of coverage tables
michael@0: 					 * in lookahead sequence, in glyph
michael@0: 					 * sequence order */
michael@0:   ArrayOf<GlyphID>
michael@0: 		substituteX;		/* Array of substitute
michael@0: 					 * GlyphIDs--ordered by Coverage Index */
michael@0:   public:
michael@0:   DEFINE_SIZE_MIN (10);
michael@0: };
michael@0: 
michael@0: struct ReverseChainSingleSubst
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:     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:     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:   ReverseChainSingleSubstFormat1	format1;
michael@0:   } u;
michael@0: };
michael@0: 
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * SubstLookup
michael@0:  */
michael@0: 
michael@0: struct SubstLookupSubTable
michael@0: {
michael@0:   friend struct SubstLookup;
michael@0: 
michael@0:   enum Type {
michael@0:     Single		= 1,
michael@0:     Multiple		= 2,
michael@0:     Alternate		= 3,
michael@0:     Ligature		= 4,
michael@0:     Context		= 5,
michael@0:     ChainContext	= 6,
michael@0:     Extension		= 7,
michael@0:     ReverseChainSingle	= 8
michael@0:   };
michael@0: 
michael@0:   template <typename context_t>
michael@0:   inline typename context_t::return_t dispatch (context_t *c, unsigned int lookup_type) const
michael@0:   {
michael@0:     TRACE_DISPATCH (this);
michael@0:     switch (lookup_type) {
michael@0:     case Single:		return TRACE_RETURN (u.single.dispatch (c));
michael@0:     case Multiple:		return TRACE_RETURN (u.multiple.dispatch (c));
michael@0:     case Alternate:		return TRACE_RETURN (u.alternate.dispatch (c));
michael@0:     case Ligature:		return TRACE_RETURN (u.ligature.dispatch (c));
michael@0:     case Context:		return TRACE_RETURN (u.context.dispatch (c));
michael@0:     case ChainContext:		return TRACE_RETURN (u.chainContext.dispatch (c));
michael@0:     case Extension:		return TRACE_RETURN (u.extension.dispatch (c));
michael@0:     case ReverseChainSingle:	return TRACE_RETURN (u.reverseChainContextSingle.dispatch (c));
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, unsigned int lookup_type) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     if (!u.header.sub_format.sanitize (c))
michael@0:       return TRACE_RETURN (false);
michael@0:     switch (lookup_type) {
michael@0:     case Single:		return TRACE_RETURN (u.single.sanitize (c));
michael@0:     case Multiple:		return TRACE_RETURN (u.multiple.sanitize (c));
michael@0:     case Alternate:		return TRACE_RETURN (u.alternate.sanitize (c));
michael@0:     case Ligature:		return TRACE_RETURN (u.ligature.sanitize (c));
michael@0:     case Context:		return TRACE_RETURN (u.context.sanitize (c));
michael@0:     case ChainContext:		return TRACE_RETURN (u.chainContext.sanitize (c));
michael@0:     case Extension:		return TRACE_RETURN (u.extension.sanitize (c));
michael@0:     case ReverseChainSingle:	return TRACE_RETURN (u.reverseChainContextSingle.sanitize (c));
michael@0:     default:			return TRACE_RETURN (true);
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   protected:
michael@0:   union {
michael@0:   struct {
michael@0:     USHORT			sub_format;
michael@0:   } header;
michael@0:   SingleSubst			single;
michael@0:   MultipleSubst			multiple;
michael@0:   AlternateSubst		alternate;
michael@0:   LigatureSubst			ligature;
michael@0:   ContextSubst			context;
michael@0:   ChainContextSubst		chainContext;
michael@0:   ExtensionSubst		extension;
michael@0:   ReverseChainSingleSubst	reverseChainContextSingle;
michael@0:   } u;
michael@0:   public:
michael@0:   DEFINE_SIZE_UNION (2, header.sub_format);
michael@0: };
michael@0: 
michael@0: 
michael@0: struct SubstLookup : Lookup
michael@0: {
michael@0:   inline const SubstLookupSubTable& get_subtable (unsigned int i) const
michael@0:   { return this+CastR<OffsetArrayOf<SubstLookupSubTable> > (subTable)[i]; }
michael@0: 
michael@0:   inline static bool lookup_type_is_reverse (unsigned int lookup_type)
michael@0:   { return lookup_type == SubstLookupSubTable::ReverseChainSingle; }
michael@0: 
michael@0:   inline bool is_reverse (void) const
michael@0:   {
michael@0:     unsigned int type = get_type ();
michael@0:     if (unlikely (type == SubstLookupSubTable::Extension))
michael@0:       return CastR<ExtensionSubst> (get_subtable(0)).is_reverse ();
michael@0:     return lookup_type_is_reverse (type);
michael@0:   }
michael@0: 
michael@0:   inline hb_closure_context_t::return_t closure (hb_closure_context_t *c) const
michael@0:   {
michael@0:     TRACE_CLOSURE (this);
michael@0:     c->set_recurse_func (dispatch_recurse_func<hb_closure_context_t>);
michael@0:     return TRACE_RETURN (dispatch (c));
michael@0:   }
michael@0: 
michael@0:   inline hb_collect_glyphs_context_t::return_t collect_glyphs (hb_collect_glyphs_context_t *c) const
michael@0:   {
michael@0:     TRACE_COLLECT_GLYPHS (this);
michael@0:     c->set_recurse_func (dispatch_recurse_func<hb_collect_glyphs_context_t>);
michael@0:     return TRACE_RETURN (dispatch (c));
michael@0:   }
michael@0: 
michael@0:   template <typename set_t>
michael@0:   inline void add_coverage (set_t *glyphs) const
michael@0:   {
michael@0:     hb_get_coverage_context_t c;
michael@0:     const Coverage *last = NULL;
michael@0:     unsigned int count = get_subtable_count ();
michael@0:     for (unsigned int i = 0; i < count; i++) {
michael@0:       const Coverage *coverage = &get_subtable (i).dispatch (&c, get_type ());
michael@0:       if (coverage != last) {
michael@0:         coverage->add_coverage (glyphs);
michael@0:         last = coverage;
michael@0:       }
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   inline bool would_apply (hb_would_apply_context_t *c, const hb_set_digest_t *digest) const
michael@0:   {
michael@0:     TRACE_WOULD_APPLY (this);
michael@0:     if (unlikely (!c->len))  return TRACE_RETURN (false);
michael@0:     if (!digest->may_have (c->glyphs[0]))  return TRACE_RETURN (false);
michael@0:       return TRACE_RETURN (dispatch (c));
michael@0:   }
michael@0: 
michael@0:   inline bool apply_once (hb_apply_context_t *c) const
michael@0:   {
michael@0:     TRACE_APPLY (this);
michael@0:     if (!c->check_glyph_property (&c->buffer->cur(), c->lookup_props))
michael@0:       return TRACE_RETURN (false);
michael@0:     return TRACE_RETURN (dispatch (c));
michael@0:   }
michael@0: 
michael@0:   static bool apply_recurse_func (hb_apply_context_t *c, unsigned int lookup_index);
michael@0: 
michael@0:   inline SubstLookupSubTable& serialize_subtable (hb_serialize_context_t *c,
michael@0: 						  unsigned int i)
michael@0:   { return CastR<OffsetArrayOf<SubstLookupSubTable> > (subTable)[i].serialize (c, this); }
michael@0: 
michael@0:   inline bool serialize_single (hb_serialize_context_t *c,
michael@0: 				uint32_t lookup_props,
michael@0: 			        Supplier<GlyphID> &glyphs,
michael@0: 			        Supplier<GlyphID> &substitutes,
michael@0: 			        unsigned int num_glyphs)
michael@0:   {
michael@0:     TRACE_SERIALIZE (this);
michael@0:     if (unlikely (!Lookup::serialize (c, SubstLookupSubTable::Single, lookup_props, 1))) return TRACE_RETURN (false);
michael@0:     return TRACE_RETURN (serialize_subtable (c, 0).u.single.serialize (c, glyphs, substitutes, num_glyphs));
michael@0:   }
michael@0: 
michael@0:   inline bool serialize_multiple (hb_serialize_context_t *c,
michael@0: 				  uint32_t lookup_props,
michael@0: 				  Supplier<GlyphID> &glyphs,
michael@0: 				  Supplier<unsigned int> &substitute_len_list,
michael@0: 				  unsigned int num_glyphs,
michael@0: 				  Supplier<GlyphID> &substitute_glyphs_list)
michael@0:   {
michael@0:     TRACE_SERIALIZE (this);
michael@0:     if (unlikely (!Lookup::serialize (c, SubstLookupSubTable::Multiple, lookup_props, 1))) return TRACE_RETURN (false);
michael@0:     return TRACE_RETURN (serialize_subtable (c, 0).u.multiple.serialize (c, glyphs, substitute_len_list, num_glyphs,
michael@0: 									 substitute_glyphs_list));
michael@0:   }
michael@0: 
michael@0:   inline bool serialize_alternate (hb_serialize_context_t *c,
michael@0: 				   uint32_t lookup_props,
michael@0: 				   Supplier<GlyphID> &glyphs,
michael@0: 				   Supplier<unsigned int> &alternate_len_list,
michael@0: 				   unsigned int num_glyphs,
michael@0: 				   Supplier<GlyphID> &alternate_glyphs_list)
michael@0:   {
michael@0:     TRACE_SERIALIZE (this);
michael@0:     if (unlikely (!Lookup::serialize (c, SubstLookupSubTable::Alternate, lookup_props, 1))) return TRACE_RETURN (false);
michael@0:     return TRACE_RETURN (serialize_subtable (c, 0).u.alternate.serialize (c, glyphs, alternate_len_list, num_glyphs,
michael@0: 									  alternate_glyphs_list));
michael@0:   }
michael@0: 
michael@0:   inline bool serialize_ligature (hb_serialize_context_t *c,
michael@0: 				  uint32_t lookup_props,
michael@0: 				  Supplier<GlyphID> &first_glyphs,
michael@0: 				  Supplier<unsigned int> &ligature_per_first_glyph_count_list,
michael@0: 				  unsigned int num_first_glyphs,
michael@0: 				  Supplier<GlyphID> &ligatures_list,
michael@0: 				  Supplier<unsigned int> &component_count_list,
michael@0: 				  Supplier<GlyphID> &component_list /* Starting from second for each ligature */)
michael@0:   {
michael@0:     TRACE_SERIALIZE (this);
michael@0:     if (unlikely (!Lookup::serialize (c, SubstLookupSubTable::Ligature, lookup_props, 1))) return TRACE_RETURN (false);
michael@0:     return TRACE_RETURN (serialize_subtable (c, 0).u.ligature.serialize (c, first_glyphs, ligature_per_first_glyph_count_list, num_first_glyphs,
michael@0: 									 ligatures_list, component_count_list, component_list));
michael@0:   }
michael@0: 
michael@0:   template <typename context_t>
michael@0:   static inline typename context_t::return_t dispatch_recurse_func (context_t *c, unsigned int lookup_index);
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:     unsigned int lookup_type = get_type ();
michael@0:     unsigned int count = get_subtable_count ();
michael@0:     for (unsigned int i = 0; i < count; i++) {
michael@0:       typename context_t::return_t r = get_subtable (i).dispatch (c, lookup_type);
michael@0:       if (c->stop_sublookup_iteration (r))
michael@0:         return TRACE_RETURN (r);
michael@0:     }
michael@0:     return TRACE_RETURN (c->default_return_value ());
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c)
michael@0:   {
michael@0:     TRACE_SANITIZE (this);
michael@0:     if (unlikely (!Lookup::sanitize (c))) return TRACE_RETURN (false);
michael@0:     OffsetArrayOf<SubstLookupSubTable> &list = CastR<OffsetArrayOf<SubstLookupSubTable> > (subTable);
michael@0:     if (unlikely (!list.sanitize (c, this, get_type ()))) return TRACE_RETURN (false);
michael@0: 
michael@0:     if (unlikely (get_type () == SubstLookupSubTable::Extension))
michael@0:     {
michael@0:       /* The spec says all subtables of an Extension lookup should
michael@0:        * have the same type.  This is specially important if one has
michael@0:        * a reverse type! */
michael@0:       unsigned int type = get_subtable (0).u.extension.get_type ();
michael@0:       unsigned int count = get_subtable_count ();
michael@0:       for (unsigned int i = 1; i < count; i++)
michael@0:         if (get_subtable (i).u.extension.get_type () != type)
michael@0: 	  return TRACE_RETURN (false);
michael@0:     }
michael@0:     return TRACE_RETURN (true);
michael@0:   }
michael@0: };
michael@0: 
michael@0: typedef OffsetListOf<SubstLookup> SubstLookupList;
michael@0: 
michael@0: /*
michael@0:  * GSUB -- The Glyph Substitution Table
michael@0:  */
michael@0: 
michael@0: struct GSUB : GSUBGPOS
michael@0: {
michael@0:   static const hb_tag_t tableTag	= HB_OT_TAG_GSUB;
michael@0: 
michael@0:   inline const SubstLookup& get_lookup (unsigned int i) const
michael@0:   { return CastR<SubstLookup> (GSUBGPOS::get_lookup (i)); }
michael@0: 
michael@0:   static inline void substitute_start (hb_font_t *font, hb_buffer_t *buffer);
michael@0:   static inline void substitute_finish (hb_font_t *font, hb_buffer_t *buffer);
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     if (unlikely (!GSUBGPOS::sanitize (c))) return TRACE_RETURN (false);
michael@0:     OffsetTo<SubstLookupList> &list = CastR<OffsetTo<SubstLookupList> > (lookupList);
michael@0:     return TRACE_RETURN (list.sanitize (c, this));
michael@0:   }
michael@0:   public:
michael@0:   DEFINE_SIZE_STATIC (10);
michael@0: };
michael@0: 
michael@0: 
michael@0: void
michael@0: GSUB::substitute_start (hb_font_t *font, hb_buffer_t *buffer)
michael@0: {
michael@0:   _hb_buffer_allocate_gsubgpos_vars (buffer);
michael@0: 
michael@0:   const GDEF &gdef = *hb_ot_layout_from_face (font->face)->gdef;
michael@0:   unsigned int count = buffer->len;
michael@0:   for (unsigned int i = 0; i < count; i++)
michael@0:   {
michael@0:     _hb_glyph_info_set_glyph_props (&buffer->info[i], gdef.get_glyph_props (buffer->info[i].codepoint));
michael@0:     _hb_glyph_info_clear_lig_props (&buffer->info[i]);
michael@0:     buffer->info[i].syllable() = 0;
michael@0:   }
michael@0: }
michael@0: 
michael@0: void
michael@0: GSUB::substitute_finish (hb_font_t *font HB_UNUSED, hb_buffer_t *buffer HB_UNUSED)
michael@0: {
michael@0: }
michael@0: 
michael@0: 
michael@0: /* Out-of-class implementation for methods recursing */
michael@0: 
michael@0: inline bool ExtensionSubst::is_reverse (void) const
michael@0: {
michael@0:   unsigned int type = get_type ();
michael@0:   if (unlikely (type == SubstLookupSubTable::Extension))
michael@0:     return CastR<ExtensionSubst> (get_subtable<SubstLookupSubTable>()).is_reverse ();
michael@0:   return SubstLookup::lookup_type_is_reverse (type);
michael@0: }
michael@0: 
michael@0: template <typename context_t>
michael@0: inline typename context_t::return_t SubstLookup::dispatch_recurse_func (context_t *c, unsigned int lookup_index)
michael@0: {
michael@0:   const GSUB &gsub = *(hb_ot_layout_from_face (c->face)->gsub);
michael@0:   const SubstLookup &l = gsub.get_lookup (lookup_index);
michael@0:   return l.dispatch (c);
michael@0: }
michael@0: 
michael@0: inline bool SubstLookup::apply_recurse_func (hb_apply_context_t *c, unsigned int lookup_index)
michael@0: {
michael@0:   const GSUB &gsub = *(hb_ot_layout_from_face (c->face)->gsub);
michael@0:   const SubstLookup &l = gsub.get_lookup (lookup_index);
michael@0:   unsigned int saved_lookup_props = c->lookup_props;
michael@0:   c->set_lookup (l);
michael@0:   bool ret = l.apply_once (c);
michael@0:   c->lookup_props = saved_lookup_props;
michael@0:   return ret;
michael@0: }
michael@0: 
michael@0: 
michael@0: } /* namespace OT */
michael@0: 
michael@0: 
michael@0: #endif /* HB_OT_LAYOUT_GSUB_TABLE_HH */