diff options
Diffstat (limited to 'gfx/harfbuzz/src/hb-ot-layout-gsub-table.hh')
| -rw-r--r-- | gfx/harfbuzz/src/hb-ot-layout-gsub-table.hh | 1369 |
1 files changed, 1369 insertions, 0 deletions
diff --git a/gfx/harfbuzz/src/hb-ot-layout-gsub-table.hh b/gfx/harfbuzz/src/hb-ot-layout-gsub-table.hh new file mode 100644 index 000000000..66fcb3f3a --- /dev/null +++ b/gfx/harfbuzz/src/hb-ot-layout-gsub-table.hh @@ -0,0 +1,1369 @@ +/* + * Copyright © 2007,2008,2009,2010 Red Hat, Inc. + * Copyright © 2010,2012,2013 Google, Inc. + * + * This is part of HarfBuzz, a text shaping library. + * + * Permission is hereby granted, without written agreement and without + * license or royalty fees, to use, copy, modify, and distribute this + * software and its documentation for any purpose, provided that the + * above copyright notice and the following two paragraphs appear in + * all copies of this software. + * + * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR + * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES + * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN + * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH + * DAMAGE. + * + * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, + * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND + * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS + * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO + * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. + * + * Red Hat Author(s): Behdad Esfahbod + * Google Author(s): Behdad Esfahbod + */ + +#ifndef HB_OT_LAYOUT_GSUB_TABLE_HH +#define HB_OT_LAYOUT_GSUB_TABLE_HH + +#include "hb-ot-layout-gsubgpos-private.hh" + + +namespace OT { + + +struct SingleSubstFormat1 +{ + inline void closure (hb_closure_context_t *c) const + { + TRACE_CLOSURE (this); + Coverage::Iter iter; + for (iter.init (this+coverage); iter.more (); iter.next ()) + { + /* TODO Switch to range-based API to work around malicious fonts. + * https://github.com/behdad/harfbuzz/issues/363 */ + hb_codepoint_t glyph_id = iter.get_glyph (); + if (c->glyphs->has (glyph_id)) + c->glyphs->add ((glyph_id + deltaGlyphID) & 0xFFFFu); + } + } + + inline void collect_glyphs (hb_collect_glyphs_context_t *c) const + { + TRACE_COLLECT_GLYPHS (this); + Coverage::Iter iter; + for (iter.init (this+coverage); iter.more (); iter.next ()) + { + /* TODO Switch to range-based API to work around malicious fonts. + * https://github.com/behdad/harfbuzz/issues/363 */ + hb_codepoint_t glyph_id = iter.get_glyph (); + c->input->add (glyph_id); + c->output->add ((glyph_id + deltaGlyphID) & 0xFFFFu); + } + } + + inline const Coverage &get_coverage (void) const + { + return this+coverage; + } + + inline bool would_apply (hb_would_apply_context_t *c) const + { + TRACE_WOULD_APPLY (this); + return_trace (c->len == 1 && (this+coverage).get_coverage (c->glyphs[0]) != NOT_COVERED); + } + + inline bool apply (hb_apply_context_t *c) const + { + TRACE_APPLY (this); + hb_codepoint_t glyph_id = c->buffer->cur().codepoint; + unsigned int index = (this+coverage).get_coverage (glyph_id); + if (likely (index == NOT_COVERED)) return_trace (false); + + /* According to the Adobe Annotated OpenType Suite, result is always + * limited to 16bit. */ + glyph_id = (glyph_id + deltaGlyphID) & 0xFFFFu; + c->replace_glyph (glyph_id); + + return_trace (true); + } + + inline bool serialize (hb_serialize_context_t *c, + Supplier<GlyphID> &glyphs, + unsigned int num_glyphs, + int delta) + { + TRACE_SERIALIZE (this); + if (unlikely (!c->extend_min (*this))) return_trace (false); + if (unlikely (!coverage.serialize (c, this).serialize (c, glyphs, num_glyphs))) return_trace (false); + deltaGlyphID.set (delta); /* TODO(serilaize) overflow? */ + return_trace (true); + } + + inline bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + return_trace (coverage.sanitize (c, this) && deltaGlyphID.sanitize (c)); + } + + protected: + USHORT format; /* Format identifier--format = 1 */ + OffsetTo<Coverage> + coverage; /* Offset to Coverage table--from + * beginning of Substitution table */ + SHORT deltaGlyphID; /* Add to original GlyphID to get + * substitute GlyphID */ + public: + DEFINE_SIZE_STATIC (6); +}; + +struct SingleSubstFormat2 +{ + inline void closure (hb_closure_context_t *c) const + { + TRACE_CLOSURE (this); + Coverage::Iter iter; + unsigned int count = substitute.len; + for (iter.init (this+coverage); iter.more (); iter.next ()) + { + if (unlikely (iter.get_coverage () >= count)) + break; /* Work around malicious fonts. https://github.com/behdad/harfbuzz/issues/363 */ + if (c->glyphs->has (iter.get_glyph ())) + c->glyphs->add (substitute[iter.get_coverage ()]); + } + } + + inline void collect_glyphs (hb_collect_glyphs_context_t *c) const + { + TRACE_COLLECT_GLYPHS (this); + Coverage::Iter iter; + unsigned int count = substitute.len; + for (iter.init (this+coverage); iter.more (); iter.next ()) + { + if (unlikely (iter.get_coverage () >= count)) + break; /* Work around malicious fonts. https://github.com/behdad/harfbuzz/issues/363 */ + c->input->add (iter.get_glyph ()); + c->output->add (substitute[iter.get_coverage ()]); + } + } + + inline const Coverage &get_coverage (void) const + { + return this+coverage; + } + + inline bool would_apply (hb_would_apply_context_t *c) const + { + TRACE_WOULD_APPLY (this); + return_trace (c->len == 1 && (this+coverage).get_coverage (c->glyphs[0]) != NOT_COVERED); + } + + inline bool apply (hb_apply_context_t *c) const + { + TRACE_APPLY (this); + hb_codepoint_t glyph_id = c->buffer->cur().codepoint; + unsigned int index = (this+coverage).get_coverage (glyph_id); + if (likely (index == NOT_COVERED)) return_trace (false); + + if (unlikely (index >= substitute.len)) return_trace (false); + + glyph_id = substitute[index]; + c->replace_glyph (glyph_id); + + return_trace (true); + } + + inline bool serialize (hb_serialize_context_t *c, + Supplier<GlyphID> &glyphs, + Supplier<GlyphID> &substitutes, + unsigned int num_glyphs) + { + TRACE_SERIALIZE (this); + if (unlikely (!c->extend_min (*this))) return_trace (false); + if (unlikely (!substitute.serialize (c, substitutes, num_glyphs))) return_trace (false); + if (unlikely (!coverage.serialize (c, this).serialize (c, glyphs, num_glyphs))) return_trace (false); + return_trace (true); + } + + inline bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + return_trace (coverage.sanitize (c, this) && substitute.sanitize (c)); + } + + protected: + USHORT format; /* Format identifier--format = 2 */ + OffsetTo<Coverage> + coverage; /* Offset to Coverage table--from + * beginning of Substitution table */ + ArrayOf<GlyphID> + substitute; /* Array of substitute + * GlyphIDs--ordered by Coverage Index */ + public: + DEFINE_SIZE_ARRAY (6, substitute); +}; + +struct SingleSubst +{ + inline bool serialize (hb_serialize_context_t *c, + Supplier<GlyphID> &glyphs, + Supplier<GlyphID> &substitutes, + unsigned int num_glyphs) + { + TRACE_SERIALIZE (this); + if (unlikely (!c->extend_min (u.format))) return_trace (false); + unsigned int format = 2; + int delta = 0; + if (num_glyphs) { + format = 1; + /* TODO(serialize) check for wrap-around */ + delta = substitutes[0] - glyphs[0]; + for (unsigned int i = 1; i < num_glyphs; i++) + if (delta != substitutes[i] - glyphs[i]) { + format = 2; + break; + } + } + u.format.set (format); + switch (u.format) { + case 1: return_trace (u.format1.serialize (c, glyphs, num_glyphs, delta)); + case 2: return_trace (u.format2.serialize (c, glyphs, substitutes, num_glyphs)); + default:return_trace (false); + } + } + + template <typename context_t> + inline typename context_t::return_t dispatch (context_t *c) const + { + TRACE_DISPATCH (this, u.format); + if (unlikely (!c->may_dispatch (this, &u.format))) return_trace (c->no_dispatch_return_value ()); + switch (u.format) { + case 1: return_trace (c->dispatch (u.format1)); + case 2: return_trace (c->dispatch (u.format2)); + default:return_trace (c->default_return_value ()); + } + } + + protected: + union { + USHORT format; /* Format identifier */ + SingleSubstFormat1 format1; + SingleSubstFormat2 format2; + } u; +}; + + +struct Sequence +{ + inline void closure (hb_closure_context_t *c) const + { + TRACE_CLOSURE (this); + unsigned int count = substitute.len; + for (unsigned int i = 0; i < count; i++) + c->glyphs->add (substitute[i]); + } + + inline void collect_glyphs (hb_collect_glyphs_context_t *c) const + { + TRACE_COLLECT_GLYPHS (this); + unsigned int count = substitute.len; + for (unsigned int i = 0; i < count; i++) + c->output->add (substitute[i]); + } + + inline bool apply (hb_apply_context_t *c) const + { + TRACE_APPLY (this); + unsigned int count = substitute.len; + + /* Special-case to make it in-place and not consider this + * as a "multiplied" substitution. */ + if (unlikely (count == 1)) + { + c->replace_glyph (substitute.array[0]); + return_trace (true); + } + /* Spec disallows this, but Uniscribe allows it. + * https://github.com/behdad/harfbuzz/issues/253 */ + else if (unlikely (count == 0)) + { + c->buffer->delete_glyph (); + return_trace (true); + } + + unsigned int klass = _hb_glyph_info_is_ligature (&c->buffer->cur()) ? + HB_OT_LAYOUT_GLYPH_PROPS_BASE_GLYPH : 0; + + for (unsigned int i = 0; i < count; i++) { + _hb_glyph_info_set_lig_props_for_component (&c->buffer->cur(), i); + c->output_glyph_for_component (substitute.array[i], klass); + } + c->buffer->skip_glyph (); + + return_trace (true); + } + + inline bool serialize (hb_serialize_context_t *c, + Supplier<GlyphID> &glyphs, + unsigned int num_glyphs) + { + TRACE_SERIALIZE (this); + if (unlikely (!c->extend_min (*this))) return_trace (false); + if (unlikely (!substitute.serialize (c, glyphs, num_glyphs))) return_trace (false); + return_trace (true); + } + + inline bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + return_trace (substitute.sanitize (c)); + } + + protected: + ArrayOf<GlyphID> + substitute; /* String of GlyphIDs to substitute */ + public: + DEFINE_SIZE_ARRAY (2, substitute); +}; + +struct MultipleSubstFormat1 +{ + inline void closure (hb_closure_context_t *c) const + { + TRACE_CLOSURE (this); + Coverage::Iter iter; + unsigned int count = sequence.len; + for (iter.init (this+coverage); iter.more (); iter.next ()) + { + if (unlikely (iter.get_coverage () >= count)) + break; /* Work around malicious fonts. https://github.com/behdad/harfbuzz/issues/363 */ + if (c->glyphs->has (iter.get_glyph ())) + (this+sequence[iter.get_coverage ()]).closure (c); + } + } + + inline void collect_glyphs (hb_collect_glyphs_context_t *c) const + { + TRACE_COLLECT_GLYPHS (this); + (this+coverage).add_coverage (c->input); + unsigned int count = sequence.len; + for (unsigned int i = 0; i < count; i++) + (this+sequence[i]).collect_glyphs (c); + } + + inline const Coverage &get_coverage (void) const + { + return this+coverage; + } + + inline bool would_apply (hb_would_apply_context_t *c) const + { + TRACE_WOULD_APPLY (this); + return_trace (c->len == 1 && (this+coverage).get_coverage (c->glyphs[0]) != NOT_COVERED); + } + + inline bool apply (hb_apply_context_t *c) const + { + TRACE_APPLY (this); + + unsigned int index = (this+coverage).get_coverage (c->buffer->cur().codepoint); + if (likely (index == NOT_COVERED)) return_trace (false); + + return_trace ((this+sequence[index]).apply (c)); + } + + inline bool serialize (hb_serialize_context_t *c, + Supplier<GlyphID> &glyphs, + Supplier<unsigned int> &substitute_len_list, + unsigned int num_glyphs, + Supplier<GlyphID> &substitute_glyphs_list) + { + TRACE_SERIALIZE (this); + if (unlikely (!c->extend_min (*this))) return_trace (false); + if (unlikely (!sequence.serialize (c, num_glyphs))) return_trace (false); + for (unsigned int i = 0; i < num_glyphs; i++) + if (unlikely (!sequence[i].serialize (c, this).serialize (c, + substitute_glyphs_list, + substitute_len_list[i]))) return_trace (false); + substitute_len_list.advance (num_glyphs); + if (unlikely (!coverage.serialize (c, this).serialize (c, glyphs, num_glyphs))) return_trace (false); + return_trace (true); + } + + inline bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + return_trace (coverage.sanitize (c, this) && sequence.sanitize (c, this)); + } + + protected: + USHORT format; /* Format identifier--format = 1 */ + OffsetTo<Coverage> + coverage; /* Offset to Coverage table--from + * beginning of Substitution table */ + OffsetArrayOf<Sequence> + sequence; /* Array of Sequence tables + * ordered by Coverage Index */ + public: + DEFINE_SIZE_ARRAY (6, sequence); +}; + +struct MultipleSubst +{ + inline bool serialize (hb_serialize_context_t *c, + Supplier<GlyphID> &glyphs, + Supplier<unsigned int> &substitute_len_list, + unsigned int num_glyphs, + Supplier<GlyphID> &substitute_glyphs_list) + { + TRACE_SERIALIZE (this); + if (unlikely (!c->extend_min (u.format))) return_trace (false); + unsigned int format = 1; + u.format.set (format); + switch (u.format) { + case 1: return_trace (u.format1.serialize (c, glyphs, substitute_len_list, num_glyphs, substitute_glyphs_list)); + default:return_trace (false); + } + } + + template <typename context_t> + inline typename context_t::return_t dispatch (context_t *c) const + { + TRACE_DISPATCH (this, u.format); + if (unlikely (!c->may_dispatch (this, &u.format))) return_trace (c->no_dispatch_return_value ()); + switch (u.format) { + case 1: return_trace (c->dispatch (u.format1)); + default:return_trace (c->default_return_value ()); + } + } + + protected: + union { + USHORT format; /* Format identifier */ + MultipleSubstFormat1 format1; + } u; +}; + + +typedef ArrayOf<GlyphID> AlternateSet; /* Array of alternate GlyphIDs--in + * arbitrary order */ + +struct AlternateSubstFormat1 +{ + inline void closure (hb_closure_context_t *c) const + { + TRACE_CLOSURE (this); + Coverage::Iter iter; + unsigned int count = alternateSet.len; + for (iter.init (this+coverage); iter.more (); iter.next ()) + { + if (unlikely (iter.get_coverage () >= count)) + break; /* Work around malicious fonts. https://github.com/behdad/harfbuzz/issues/363 */ + if (c->glyphs->has (iter.get_glyph ())) { + const AlternateSet &alt_set = this+alternateSet[iter.get_coverage ()]; + unsigned int count = alt_set.len; + for (unsigned int i = 0; i < count; i++) + c->glyphs->add (alt_set[i]); + } + } + } + + inline void collect_glyphs (hb_collect_glyphs_context_t *c) const + { + TRACE_COLLECT_GLYPHS (this); + Coverage::Iter iter; + unsigned int count = alternateSet.len; + for (iter.init (this+coverage); iter.more (); iter.next ()) + { + if (unlikely (iter.get_coverage () >= count)) + break; /* Work around malicious fonts. https://github.com/behdad/harfbuzz/issues/363 */ + c->input->add (iter.get_glyph ()); + const AlternateSet &alt_set = this+alternateSet[iter.get_coverage ()]; + unsigned int count = alt_set.len; + for (unsigned int i = 0; i < count; i++) + c->output->add (alt_set[i]); + } + } + + inline const Coverage &get_coverage (void) const + { + return this+coverage; + } + + inline bool would_apply (hb_would_apply_context_t *c) const + { + TRACE_WOULD_APPLY (this); + return_trace (c->len == 1 && (this+coverage).get_coverage (c->glyphs[0]) != NOT_COVERED); + } + + inline bool apply (hb_apply_context_t *c) const + { + TRACE_APPLY (this); + hb_codepoint_t glyph_id = c->buffer->cur().codepoint; + + unsigned int index = (this+coverage).get_coverage (glyph_id); + if (likely (index == NOT_COVERED)) return_trace (false); + + const AlternateSet &alt_set = this+alternateSet[index]; + + if (unlikely (!alt_set.len)) return_trace (false); + + hb_mask_t glyph_mask = c->buffer->cur().mask; + hb_mask_t lookup_mask = c->lookup_mask; + + /* Note: This breaks badly if two features enabled this lookup together. */ + unsigned int shift = _hb_ctz (lookup_mask); + unsigned int alt_index = ((lookup_mask & glyph_mask) >> shift); + + if (unlikely (alt_index > alt_set.len || alt_index == 0)) return_trace (false); + + glyph_id = alt_set[alt_index - 1]; + + c->replace_glyph (glyph_id); + + return_trace (true); + } + + inline bool serialize (hb_serialize_context_t *c, + Supplier<GlyphID> &glyphs, + Supplier<unsigned int> &alternate_len_list, + unsigned int num_glyphs, + Supplier<GlyphID> &alternate_glyphs_list) + { + TRACE_SERIALIZE (this); + if (unlikely (!c->extend_min (*this))) return_trace (false); + if (unlikely (!alternateSet.serialize (c, num_glyphs))) return_trace (false); + for (unsigned int i = 0; i < num_glyphs; i++) + if (unlikely (!alternateSet[i].serialize (c, this).serialize (c, + alternate_glyphs_list, + alternate_len_list[i]))) return_trace (false); + alternate_len_list.advance (num_glyphs); + if (unlikely (!coverage.serialize (c, this).serialize (c, glyphs, num_glyphs))) return_trace (false); + return_trace (true); + } + + inline bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + return_trace (coverage.sanitize (c, this) && alternateSet.sanitize (c, this)); + } + + protected: + USHORT format; /* Format identifier--format = 1 */ + OffsetTo<Coverage> + coverage; /* Offset to Coverage table--from + * beginning of Substitution table */ + OffsetArrayOf<AlternateSet> + alternateSet; /* Array of AlternateSet tables + * ordered by Coverage Index */ + public: + DEFINE_SIZE_ARRAY (6, alternateSet); +}; + +struct AlternateSubst +{ + inline bool serialize (hb_serialize_context_t *c, + Supplier<GlyphID> &glyphs, + Supplier<unsigned int> &alternate_len_list, + unsigned int num_glyphs, + Supplier<GlyphID> &alternate_glyphs_list) + { + TRACE_SERIALIZE (this); + if (unlikely (!c->extend_min (u.format))) return_trace (false); + unsigned int format = 1; + u.format.set (format); + switch (u.format) { + case 1: return_trace (u.format1.serialize (c, glyphs, alternate_len_list, num_glyphs, alternate_glyphs_list)); + default:return_trace (false); + } + } + + template <typename context_t> + inline typename context_t::return_t dispatch (context_t *c) const + { + TRACE_DISPATCH (this, u.format); + if (unlikely (!c->may_dispatch (this, &u.format))) return_trace (c->no_dispatch_return_value ()); + switch (u.format) { + case 1: return_trace (c->dispatch (u.format1)); + default:return_trace (c->default_return_value ()); + } + } + + protected: + union { + USHORT format; /* Format identifier */ + AlternateSubstFormat1 format1; + } u; +}; + + +struct Ligature +{ + inline void closure (hb_closure_context_t *c) const + { + TRACE_CLOSURE (this); + unsigned int count = component.len; + for (unsigned int i = 1; i < count; i++) + if (!c->glyphs->has (component[i])) + return; + c->glyphs->add (ligGlyph); + } + + inline void collect_glyphs (hb_collect_glyphs_context_t *c) const + { + TRACE_COLLECT_GLYPHS (this); + unsigned int count = component.len; + for (unsigned int i = 1; i < count; i++) + c->input->add (component[i]); + c->output->add (ligGlyph); + } + + inline bool would_apply (hb_would_apply_context_t *c) const + { + TRACE_WOULD_APPLY (this); + if (c->len != component.len) + return_trace (false); + + for (unsigned int i = 1; i < c->len; i++) + if (likely (c->glyphs[i] != component[i])) + return_trace (false); + + return_trace (true); + } + + inline bool apply (hb_apply_context_t *c) const + { + TRACE_APPLY (this); + unsigned int count = component.len; + + if (unlikely (!count)) return_trace (false); + + /* Special-case to make it in-place and not consider this + * as a "ligated" substitution. */ + if (unlikely (count == 1)) + { + c->replace_glyph (ligGlyph); + return_trace (true); + } + + bool is_mark_ligature = false; + unsigned int total_component_count = 0; + + unsigned int match_length = 0; + unsigned int match_positions[HB_MAX_CONTEXT_LENGTH]; + + if (likely (!match_input (c, count, + &component[1], + match_glyph, + NULL, + &match_length, + match_positions, + &is_mark_ligature, + &total_component_count))) + return_trace (false); + + ligate_input (c, + count, + match_positions, + match_length, + ligGlyph, + is_mark_ligature, + total_component_count); + + return_trace (true); + } + + inline bool serialize (hb_serialize_context_t *c, + GlyphID ligature, + Supplier<GlyphID> &components, /* Starting from second */ + unsigned int num_components /* Including first component */) + { + TRACE_SERIALIZE (this); + if (unlikely (!c->extend_min (*this))) return_trace (false); + ligGlyph = ligature; + if (unlikely (!component.serialize (c, components, num_components))) return_trace (false); + return_trace (true); + } + + public: + inline bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + return_trace (ligGlyph.sanitize (c) && component.sanitize (c)); + } + + protected: + GlyphID ligGlyph; /* GlyphID of ligature to substitute */ + HeadlessArrayOf<GlyphID> + component; /* Array of component GlyphIDs--start + * with the second component--ordered + * in writing direction */ + public: + DEFINE_SIZE_ARRAY (4, component); +}; + +struct LigatureSet +{ + inline void closure (hb_closure_context_t *c) const + { + TRACE_CLOSURE (this); + unsigned int num_ligs = ligature.len; + for (unsigned int i = 0; i < num_ligs; i++) + (this+ligature[i]).closure (c); + } + + inline void collect_glyphs (hb_collect_glyphs_context_t *c) const + { + TRACE_COLLECT_GLYPHS (this); + unsigned int num_ligs = ligature.len; + for (unsigned int i = 0; i < num_ligs; i++) + (this+ligature[i]).collect_glyphs (c); + } + + inline bool would_apply (hb_would_apply_context_t *c) const + { + TRACE_WOULD_APPLY (this); + unsigned int num_ligs = ligature.len; + for (unsigned int i = 0; i < num_ligs; i++) + { + const Ligature &lig = this+ligature[i]; + if (lig.would_apply (c)) + return_trace (true); + } + return_trace (false); + } + + inline bool apply (hb_apply_context_t *c) const + { + TRACE_APPLY (this); + unsigned int num_ligs = ligature.len; + for (unsigned int i = 0; i < num_ligs; i++) + { + const Ligature &lig = this+ligature[i]; + if (lig.apply (c)) return_trace (true); + } + + return_trace (false); + } + + inline bool serialize (hb_serialize_context_t *c, + Supplier<GlyphID> &ligatures, + Supplier<unsigned int> &component_count_list, + unsigned int num_ligatures, + Supplier<GlyphID> &component_list /* Starting from second for each ligature */) + { + TRACE_SERIALIZE (this); + if (unlikely (!c->extend_min (*this))) return_trace (false); + if (unlikely (!ligature.serialize (c, num_ligatures))) return_trace (false); + for (unsigned int i = 0; i < num_ligatures; i++) + if (unlikely (!ligature[i].serialize (c, this).serialize (c, + ligatures[i], + component_list, + component_count_list[i]))) return_trace (false); + ligatures.advance (num_ligatures); + component_count_list.advance (num_ligatures); + return_trace (true); + } + + inline bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + return_trace (ligature.sanitize (c, this)); + } + + protected: + OffsetArrayOf<Ligature> + ligature; /* Array LigatureSet tables + * ordered by preference */ + public: + DEFINE_SIZE_ARRAY (2, ligature); +}; + +struct LigatureSubstFormat1 +{ + inline void closure (hb_closure_context_t *c) const + { + TRACE_CLOSURE (this); + Coverage::Iter iter; + unsigned int count = ligatureSet.len; + for (iter.init (this+coverage); iter.more (); iter.next ()) + { + if (unlikely (iter.get_coverage () >= count)) + break; /* Work around malicious fonts. https://github.com/behdad/harfbuzz/issues/363 */ + if (c->glyphs->has (iter.get_glyph ())) + (this+ligatureSet[iter.get_coverage ()]).closure (c); + } + } + + inline void collect_glyphs (hb_collect_glyphs_context_t *c) const + { + TRACE_COLLECT_GLYPHS (this); + Coverage::Iter iter; + unsigned int count = ligatureSet.len; + for (iter.init (this+coverage); iter.more (); iter.next ()) + { + if (unlikely (iter.get_coverage () >= count)) + break; /* Work around malicious fonts. https://github.com/behdad/harfbuzz/issues/363 */ + c->input->add (iter.get_glyph ()); + (this+ligatureSet[iter.get_coverage ()]).collect_glyphs (c); + } + } + + inline const Coverage &get_coverage (void) const + { + return this+coverage; + } + + inline bool would_apply (hb_would_apply_context_t *c) const + { + TRACE_WOULD_APPLY (this); + unsigned int index = (this+coverage).get_coverage (c->glyphs[0]); + if (likely (index == NOT_COVERED)) return_trace (false); + + const LigatureSet &lig_set = this+ligatureSet[index]; + return_trace (lig_set.would_apply (c)); + } + + inline bool apply (hb_apply_context_t *c) const + { + TRACE_APPLY (this); + hb_codepoint_t glyph_id = c->buffer->cur().codepoint; + + unsigned int index = (this+coverage).get_coverage (glyph_id); + if (likely (index == NOT_COVERED)) return_trace (false); + + const LigatureSet &lig_set = this+ligatureSet[index]; + return_trace (lig_set.apply (c)); + } + + inline bool serialize (hb_serialize_context_t *c, + Supplier<GlyphID> &first_glyphs, + Supplier<unsigned int> &ligature_per_first_glyph_count_list, + unsigned int num_first_glyphs, + Supplier<GlyphID> &ligatures_list, + Supplier<unsigned int> &component_count_list, + Supplier<GlyphID> &component_list /* Starting from second for each ligature */) + { + TRACE_SERIALIZE (this); + if (unlikely (!c->extend_min (*this))) return_trace (false); + if (unlikely (!ligatureSet.serialize (c, num_first_glyphs))) return_trace (false); + for (unsigned int i = 0; i < num_first_glyphs; i++) + if (unlikely (!ligatureSet[i].serialize (c, this).serialize (c, + ligatures_list, + component_count_list, + ligature_per_first_glyph_count_list[i], + component_list))) return_trace (false); + ligature_per_first_glyph_count_list.advance (num_first_glyphs); + if (unlikely (!coverage.serialize (c, this).serialize (c, first_glyphs, num_first_glyphs))) return_trace (false); + return_trace (true); + } + + inline bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + return_trace (coverage.sanitize (c, this) && ligatureSet.sanitize (c, this)); + } + + protected: + USHORT format; /* Format identifier--format = 1 */ + OffsetTo<Coverage> + coverage; /* Offset to Coverage table--from + * beginning of Substitution table */ + OffsetArrayOf<LigatureSet> + ligatureSet; /* Array LigatureSet tables + * ordered by Coverage Index */ + public: + DEFINE_SIZE_ARRAY (6, ligatureSet); +}; + +struct LigatureSubst +{ + inline bool serialize (hb_serialize_context_t *c, + Supplier<GlyphID> &first_glyphs, + Supplier<unsigned int> &ligature_per_first_glyph_count_list, + unsigned int num_first_glyphs, + Supplier<GlyphID> &ligatures_list, + Supplier<unsigned int> &component_count_list, + Supplier<GlyphID> &component_list /* Starting from second for each ligature */) + { + TRACE_SERIALIZE (this); + if (unlikely (!c->extend_min (u.format))) return_trace (false); + unsigned int format = 1; + u.format.set (format); + switch (u.format) { + case 1: return_trace (u.format1.serialize (c, + first_glyphs, + ligature_per_first_glyph_count_list, + num_first_glyphs, + ligatures_list, + component_count_list, + component_list)); + default:return_trace (false); + } + } + + template <typename context_t> + inline typename context_t::return_t dispatch (context_t *c) const + { + TRACE_DISPATCH (this, u.format); + if (unlikely (!c->may_dispatch (this, &u.format))) return_trace (c->no_dispatch_return_value ()); + switch (u.format) { + case 1: return_trace (c->dispatch (u.format1)); + default:return_trace (c->default_return_value ()); + } + } + + protected: + union { + USHORT format; /* Format identifier */ + LigatureSubstFormat1 format1; + } u; +}; + + +struct ContextSubst : Context {}; + +struct ChainContextSubst : ChainContext {}; + +struct ExtensionSubst : Extension<ExtensionSubst> +{ + typedef struct SubstLookupSubTable LookupSubTable; + + inline bool is_reverse (void) const; +}; + + +struct ReverseChainSingleSubstFormat1 +{ + inline void closure (hb_closure_context_t *c) const + { + TRACE_CLOSURE (this); + const OffsetArrayOf<Coverage> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (backtrack); + + unsigned int count; + + count = backtrack.len; + for (unsigned int i = 0; i < count; i++) + if (!(this+backtrack[i]).intersects (c->glyphs)) + return; + + count = lookahead.len; + for (unsigned int i = 0; i < count; i++) + if (!(this+lookahead[i]).intersects (c->glyphs)) + return; + + const ArrayOf<GlyphID> &substitute = StructAfter<ArrayOf<GlyphID> > (lookahead); + Coverage::Iter iter; + count = substitute.len; + for (iter.init (this+coverage); iter.more (); iter.next ()) + { + if (unlikely (iter.get_coverage () >= count)) + break; /* Work around malicious fonts. https://github.com/behdad/harfbuzz/issues/363 */ + if (c->glyphs->has (iter.get_glyph ())) + c->glyphs->add (substitute[iter.get_coverage ()]); + } + } + + inline void collect_glyphs (hb_collect_glyphs_context_t *c) const + { + TRACE_COLLECT_GLYPHS (this); + + const OffsetArrayOf<Coverage> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (backtrack); + + unsigned int count; + + (this+coverage).add_coverage (c->input); + + count = backtrack.len; + for (unsigned int i = 0; i < count; i++) + (this+backtrack[i]).add_coverage (c->before); + + count = lookahead.len; + for (unsigned int i = 0; i < count; i++) + (this+lookahead[i]).add_coverage (c->after); + + const ArrayOf<GlyphID> &substitute = StructAfter<ArrayOf<GlyphID> > (lookahead); + count = substitute.len; + for (unsigned int i = 0; i < count; i++) + c->output->add (substitute[i]); + } + + inline const Coverage &get_coverage (void) const + { + return this+coverage; + } + + inline bool would_apply (hb_would_apply_context_t *c) const + { + TRACE_WOULD_APPLY (this); + return_trace (c->len == 1 && (this+coverage).get_coverage (c->glyphs[0]) != NOT_COVERED); + } + + inline bool apply (hb_apply_context_t *c) const + { + TRACE_APPLY (this); + if (unlikely (c->nesting_level_left != HB_MAX_NESTING_LEVEL)) + return_trace (false); /* No chaining to this type */ + + unsigned int index = (this+coverage).get_coverage (c->buffer->cur().codepoint); + if (likely (index == NOT_COVERED)) return_trace (false); + + const OffsetArrayOf<Coverage> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (backtrack); + const ArrayOf<GlyphID> &substitute = StructAfter<ArrayOf<GlyphID> > (lookahead); + + if (match_backtrack (c, + backtrack.len, (USHORT *) backtrack.array, + match_coverage, this) && + match_lookahead (c, + lookahead.len, (USHORT *) lookahead.array, + match_coverage, this, + 1)) + { + c->replace_glyph_inplace (substitute[index]); + /* Note: We DON'T decrease buffer->idx. The main loop does it + * for us. This is useful for preventing surprises if someone + * calls us through a Context lookup. */ + return_trace (true); + } + + return_trace (false); + } + + inline bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + if (!(coverage.sanitize (c, this) && backtrack.sanitize (c, this))) + return_trace (false); + const OffsetArrayOf<Coverage> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (backtrack); + if (!lookahead.sanitize (c, this)) + return_trace (false); + const ArrayOf<GlyphID> &substitute = StructAfter<ArrayOf<GlyphID> > (lookahead); + return_trace (substitute.sanitize (c)); + } + + protected: + USHORT format; /* Format identifier--format = 1 */ + OffsetTo<Coverage> + coverage; /* Offset to Coverage table--from + * beginning of table */ + OffsetArrayOf<Coverage> + backtrack; /* Array of coverage tables + * in backtracking sequence, in glyph + * sequence order */ + OffsetArrayOf<Coverage> + lookaheadX; /* Array of coverage tables + * in lookahead sequence, in glyph + * sequence order */ + ArrayOf<GlyphID> + substituteX; /* Array of substitute + * GlyphIDs--ordered by Coverage Index */ + public: + DEFINE_SIZE_MIN (10); +}; + +struct ReverseChainSingleSubst +{ + template <typename context_t> + inline typename context_t::return_t dispatch (context_t *c) const + { + TRACE_DISPATCH (this, u.format); + if (unlikely (!c->may_dispatch (this, &u.format))) return_trace (c->no_dispatch_return_value ()); + switch (u.format) { + case 1: return_trace (c->dispatch (u.format1)); + default:return_trace (c->default_return_value ()); + } + } + + protected: + union { + USHORT format; /* Format identifier */ + ReverseChainSingleSubstFormat1 format1; + } u; +}; + + + +/* + * SubstLookup + */ + +struct SubstLookupSubTable +{ + friend struct SubstLookup; + + enum Type { + Single = 1, + Multiple = 2, + Alternate = 3, + Ligature = 4, + Context = 5, + ChainContext = 6, + Extension = 7, + ReverseChainSingle = 8 + }; + + template <typename context_t> + inline typename context_t::return_t dispatch (context_t *c, unsigned int lookup_type) const + { + TRACE_DISPATCH (this, lookup_type); + if (unlikely (!c->may_dispatch (this, &u.sub_format))) return_trace (c->no_dispatch_return_value ()); + switch (lookup_type) { + case Single: return_trace (u.single.dispatch (c)); + case Multiple: return_trace (u.multiple.dispatch (c)); + case Alternate: return_trace (u.alternate.dispatch (c)); + case Ligature: return_trace (u.ligature.dispatch (c)); + case Context: return_trace (u.context.dispatch (c)); + case ChainContext: return_trace (u.chainContext.dispatch (c)); + case Extension: return_trace (u.extension.dispatch (c)); + case ReverseChainSingle: return_trace (u.reverseChainContextSingle.dispatch (c)); + default: return_trace (c->default_return_value ()); + } + } + + protected: + union { + USHORT sub_format; + SingleSubst single; + MultipleSubst multiple; + AlternateSubst alternate; + LigatureSubst ligature; + ContextSubst context; + ChainContextSubst chainContext; + ExtensionSubst extension; + ReverseChainSingleSubst reverseChainContextSingle; + } u; + public: + DEFINE_SIZE_UNION (2, sub_format); +}; + + +struct SubstLookup : Lookup +{ + inline const SubstLookupSubTable& get_subtable (unsigned int i) const + { return Lookup::get_subtable<SubstLookupSubTable> (i); } + + inline static bool lookup_type_is_reverse (unsigned int lookup_type) + { return lookup_type == SubstLookupSubTable::ReverseChainSingle; } + + inline bool is_reverse (void) const + { + unsigned int type = get_type (); + if (unlikely (type == SubstLookupSubTable::Extension)) + return CastR<ExtensionSubst> (get_subtable(0)).is_reverse (); + return lookup_type_is_reverse (type); + } + + inline bool apply (hb_apply_context_t *c) const + { + TRACE_APPLY (this); + return_trace (dispatch (c)); + } + + inline hb_closure_context_t::return_t closure (hb_closure_context_t *c) const + { + TRACE_CLOSURE (this); + c->set_recurse_func (dispatch_recurse_func<hb_closure_context_t>); + return_trace (dispatch (c)); + } + + inline hb_collect_glyphs_context_t::return_t collect_glyphs (hb_collect_glyphs_context_t *c) const + { + TRACE_COLLECT_GLYPHS (this); + c->set_recurse_func (dispatch_recurse_func<hb_collect_glyphs_context_t>); + return_trace (dispatch (c)); + } + + template <typename set_t> + inline void add_coverage (set_t *glyphs) const + { + hb_add_coverage_context_t<set_t> c (glyphs); + dispatch (&c); + } + + inline bool would_apply (hb_would_apply_context_t *c, + const hb_ot_layout_lookup_accelerator_t *accel) const + { + TRACE_WOULD_APPLY (this); + if (unlikely (!c->len)) return_trace (false); + if (!accel->may_have (c->glyphs[0])) return_trace (false); + return_trace (dispatch (c)); + } + + static bool apply_recurse_func (hb_apply_context_t *c, unsigned int lookup_index); + + inline SubstLookupSubTable& serialize_subtable (hb_serialize_context_t *c, + unsigned int i) + { return get_subtables<SubstLookupSubTable> ()[i].serialize (c, this); } + + inline bool serialize_single (hb_serialize_context_t *c, + uint32_t lookup_props, + Supplier<GlyphID> &glyphs, + Supplier<GlyphID> &substitutes, + unsigned int num_glyphs) + { + TRACE_SERIALIZE (this); + if (unlikely (!Lookup::serialize (c, SubstLookupSubTable::Single, lookup_props, 1))) return_trace (false); + return_trace (serialize_subtable (c, 0).u.single.serialize (c, glyphs, substitutes, num_glyphs)); + } + + inline bool serialize_multiple (hb_serialize_context_t *c, + uint32_t lookup_props, + Supplier<GlyphID> &glyphs, + Supplier<unsigned int> &substitute_len_list, + unsigned int num_glyphs, + Supplier<GlyphID> &substitute_glyphs_list) + { + TRACE_SERIALIZE (this); + if (unlikely (!Lookup::serialize (c, SubstLookupSubTable::Multiple, lookup_props, 1))) return_trace (false); + return_trace (serialize_subtable (c, 0).u.multiple.serialize (c, + glyphs, + substitute_len_list, + num_glyphs, + substitute_glyphs_list)); + } + + inline bool serialize_alternate (hb_serialize_context_t *c, + uint32_t lookup_props, + Supplier<GlyphID> &glyphs, + Supplier<unsigned int> &alternate_len_list, + unsigned int num_glyphs, + Supplier<GlyphID> &alternate_glyphs_list) + { + TRACE_SERIALIZE (this); + if (unlikely (!Lookup::serialize (c, SubstLookupSubTable::Alternate, lookup_props, 1))) return_trace (false); + return_trace (serialize_subtable (c, 0).u.alternate.serialize (c, + glyphs, + alternate_len_list, + num_glyphs, + alternate_glyphs_list)); + } + + inline bool serialize_ligature (hb_serialize_context_t *c, + uint32_t lookup_props, + Supplier<GlyphID> &first_glyphs, + Supplier<unsigned int> &ligature_per_first_glyph_count_list, + unsigned int num_first_glyphs, + Supplier<GlyphID> &ligatures_list, + Supplier<unsigned int> &component_count_list, + Supplier<GlyphID> &component_list /* Starting from second for each ligature */) + { + TRACE_SERIALIZE (this); + if (unlikely (!Lookup::serialize (c, SubstLookupSubTable::Ligature, lookup_props, 1))) return_trace (false); + return_trace (serialize_subtable (c, 0).u.ligature.serialize (c, + first_glyphs, + ligature_per_first_glyph_count_list, + num_first_glyphs, + ligatures_list, + component_count_list, + component_list)); + } + + template <typename context_t> + static inline typename context_t::return_t dispatch_recurse_func (context_t *c, unsigned int lookup_index); + + template <typename context_t> + inline typename context_t::return_t dispatch (context_t *c) const + { return Lookup::dispatch<SubstLookupSubTable> (c); } + + inline bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + if (unlikely (!Lookup::sanitize (c))) return_trace (false); + if (unlikely (!dispatch (c))) return_trace (false); + + if (unlikely (get_type () == SubstLookupSubTable::Extension)) + { + /* The spec says all subtables of an Extension lookup should + * have the same type. This is specially important if one has + * a reverse type! */ + unsigned int type = get_subtable (0).u.extension.get_type (); + unsigned int count = get_subtable_count (); + for (unsigned int i = 1; i < count; i++) + if (get_subtable (i).u.extension.get_type () != type) + return_trace (false); + } + return_trace (true); + } +}; + +typedef OffsetListOf<SubstLookup> SubstLookupList; + +/* + * GSUB -- The Glyph Substitution Table + */ + +struct GSUB : GSUBGPOS +{ + static const hb_tag_t tableTag = HB_OT_TAG_GSUB; + + inline const SubstLookup& get_lookup (unsigned int i) const + { return CastR<SubstLookup> (GSUBGPOS::get_lookup (i)); } + + static inline void substitute_start (hb_font_t *font, hb_buffer_t *buffer); + + inline bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + if (unlikely (!GSUBGPOS::sanitize (c))) return_trace (false); + const OffsetTo<SubstLookupList> &list = CastR<OffsetTo<SubstLookupList> > (lookupList); + return_trace (list.sanitize (c, this)); + } +}; + + +void +GSUB::substitute_start (hb_font_t *font, hb_buffer_t *buffer) +{ + _hb_buffer_assert_gsubgpos_vars (buffer); + + const GDEF &gdef = *hb_ot_layout_from_face (font->face)->gdef; + unsigned int count = buffer->len; + for (unsigned int i = 0; i < count; i++) + { + _hb_glyph_info_set_glyph_props (&buffer->info[i], gdef.get_glyph_props (buffer->info[i].codepoint)); + _hb_glyph_info_clear_lig_props (&buffer->info[i]); + buffer->info[i].syllable() = 0; + } +} + + +/* Out-of-class implementation for methods recursing */ + +/*static*/ inline bool ExtensionSubst::is_reverse (void) const +{ + unsigned int type = get_type (); + if (unlikely (type == SubstLookupSubTable::Extension)) + return CastR<ExtensionSubst> (get_subtable<LookupSubTable>()).is_reverse (); + return SubstLookup::lookup_type_is_reverse (type); +} + +template <typename context_t> +/*static*/ inline typename context_t::return_t SubstLookup::dispatch_recurse_func (context_t *c, unsigned int lookup_index) +{ + const GSUB &gsub = *(hb_ot_layout_from_face (c->face)->gsub); + const SubstLookup &l = gsub.get_lookup (lookup_index); + return l.dispatch (c); +} + +/*static*/ inline bool SubstLookup::apply_recurse_func (hb_apply_context_t *c, unsigned int lookup_index) +{ + const GSUB &gsub = *(hb_ot_layout_from_face (c->face)->gsub); + const SubstLookup &l = gsub.get_lookup (lookup_index); + unsigned int saved_lookup_props = c->lookup_props; + unsigned int saved_lookup_index = c->lookup_index; + c->set_lookup_index (lookup_index); + c->set_lookup_props (l.get_props ()); + bool ret = l.dispatch (c); + c->set_lookup_index (saved_lookup_index); + c->set_lookup_props (saved_lookup_props); + return ret; +} + + +} /* namespace OT */ + + +#endif /* HB_OT_LAYOUT_GSUB_TABLE_HH */ |