/* * Copyright © 2007,2008,2009,2010 Red Hat, Inc. * Copyright © 2010,2012 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_GSUBGPOS_HH #define HB_OT_LAYOUT_GSUBGPOS_HH #include "hb.hh" #include "hb-buffer.hh" #include "hb-map.hh" #include "hb-set.hh" #include "hb-ot-map.hh" #include "hb-ot-layout-common.hh" #include "hb-ot-layout-gdef-table.hh" namespace OT { struct hb_intersects_context_t : hb_dispatch_context_t { template return_t dispatch (const T &obj) { return obj.intersects (this->glyphs); } static return_t default_return_value () { return false; } bool stop_sublookup_iteration (return_t r) const { return r; } const hb_set_t *glyphs; hb_intersects_context_t (const hb_set_t *glyphs_) : glyphs (glyphs_) {} }; struct hb_have_non_1to1_context_t : hb_dispatch_context_t { template return_t dispatch (const T &obj) { return obj.may_have_non_1to1 (); } static return_t default_return_value () { return false; } bool stop_sublookup_iteration (return_t r) const { return r; } }; struct hb_closure_context_t : hb_dispatch_context_t { typedef return_t (*recurse_func_t) (hb_closure_context_t *c, unsigned lookup_index, hb_set_t *covered_seq_indicies, unsigned seq_index, unsigned end_index); template return_t dispatch (const T &obj) { obj.closure (this); return hb_empty_t (); } static return_t default_return_value () { return hb_empty_t (); } void recurse (unsigned lookup_index, hb_set_t *covered_seq_indicies, unsigned seq_index, unsigned end_index) { if (unlikely (nesting_level_left == 0 || !recurse_func)) return; nesting_level_left--; recurse_func (this, lookup_index, covered_seq_indicies, seq_index, end_index); nesting_level_left++; } void reset_lookup_visit_count () { lookup_count = 0; } bool lookup_limit_exceeded () { return lookup_count > HB_MAX_LOOKUP_VISIT_COUNT; } bool should_visit_lookup (unsigned int lookup_index) { if (lookup_count++ > HB_MAX_LOOKUP_VISIT_COUNT) return false; if (is_lookup_done (lookup_index)) return false; return true; } bool is_lookup_done (unsigned int lookup_index) { if (done_lookups_glyph_count->in_error () || done_lookups_glyph_set->in_error ()) return true; /* Have we visited this lookup with the current set of glyphs? */ if (done_lookups_glyph_count->get (lookup_index) != glyphs->get_population ()) { done_lookups_glyph_count->set (lookup_index, glyphs->get_population ()); if (!done_lookups_glyph_set->get (lookup_index)) { hb_set_t* empty_set = hb_set_create (); if (unlikely (!done_lookups_glyph_set->set (lookup_index, empty_set))) { hb_set_destroy (empty_set); return true; } } hb_set_clear (done_lookups_glyph_set->get (lookup_index)); } hb_set_t *covered_glyph_set = done_lookups_glyph_set->get (lookup_index); if (unlikely (covered_glyph_set->in_error ())) return true; if (parent_active_glyphs ().is_subset (*covered_glyph_set)) return true; covered_glyph_set->union_ (parent_active_glyphs ()); return false; } const hb_set_t& previous_parent_active_glyphs () { if (active_glyphs_stack.length <= 1) return *glyphs; return active_glyphs_stack[active_glyphs_stack.length - 2]; } const hb_set_t& parent_active_glyphs () { if (!active_glyphs_stack) return *glyphs; return active_glyphs_stack.tail (); } hb_set_t& push_cur_active_glyphs () { return *active_glyphs_stack.push (); } bool pop_cur_done_glyphs () { if (active_glyphs_stack.length < 1) return false; active_glyphs_stack.pop (); return true; } hb_face_t *face; hb_set_t *glyphs; hb_set_t output[1]; hb_vector_t active_glyphs_stack; recurse_func_t recurse_func; unsigned int nesting_level_left; hb_closure_context_t (hb_face_t *face_, hb_set_t *glyphs_, hb_map_t *done_lookups_glyph_count_, hb_hashmap_t *done_lookups_glyph_set_, unsigned int nesting_level_left_ = HB_MAX_NESTING_LEVEL) : face (face_), glyphs (glyphs_), recurse_func (nullptr), nesting_level_left (nesting_level_left_), done_lookups_glyph_count (done_lookups_glyph_count_), done_lookups_glyph_set (done_lookups_glyph_set_), lookup_count (0) {} ~hb_closure_context_t () { flush (); } void set_recurse_func (recurse_func_t func) { recurse_func = func; } void flush () { output->del_range (face->get_num_glyphs (), HB_SET_VALUE_INVALID); /* Remove invalid glyphs. */ glyphs->union_ (*output); output->clear (); active_glyphs_stack.pop (); active_glyphs_stack.reset (); } private: hb_map_t *done_lookups_glyph_count; hb_hashmap_t *done_lookups_glyph_set; unsigned int lookup_count; }; struct hb_closure_lookups_context_t : hb_dispatch_context_t { typedef return_t (*recurse_func_t) (hb_closure_lookups_context_t *c, unsigned lookup_index); template return_t dispatch (const T &obj) { obj.closure_lookups (this); return hb_empty_t (); } static return_t default_return_value () { return hb_empty_t (); } void recurse (unsigned lookup_index) { if (unlikely (nesting_level_left == 0 || !recurse_func)) return; /* Return if new lookup was recursed to before. */ if (lookup_limit_exceeded () || visited_lookups->in_error () || visited_lookups->has (lookup_index)) // Don't increment lookup count here, that will be done in the call to closure_lookups() // made by recurse_func. return; nesting_level_left--; recurse_func (this, lookup_index); nesting_level_left++; } void set_lookup_visited (unsigned lookup_index) { visited_lookups->add (lookup_index); } void set_lookup_inactive (unsigned lookup_index) { inactive_lookups->add (lookup_index); } bool lookup_limit_exceeded () { bool ret = lookup_count > HB_MAX_LOOKUP_VISIT_COUNT; if (ret) DEBUG_MSG (SUBSET, nullptr, "lookup visit count limit exceeded in lookup closure!"); return ret; } bool is_lookup_visited (unsigned lookup_index) { if (unlikely (lookup_count++ > HB_MAX_LOOKUP_VISIT_COUNT)) { DEBUG_MSG (SUBSET, nullptr, "total visited lookup count %u exceeds max limit, lookup %u is dropped.", lookup_count, lookup_index); return true; } if (unlikely (visited_lookups->in_error ())) return true; return visited_lookups->has (lookup_index); } hb_face_t *face; const hb_set_t *glyphs; recurse_func_t recurse_func; unsigned int nesting_level_left; hb_closure_lookups_context_t (hb_face_t *face_, const hb_set_t *glyphs_, hb_set_t *visited_lookups_, hb_set_t *inactive_lookups_, unsigned nesting_level_left_ = HB_MAX_NESTING_LEVEL) : face (face_), glyphs (glyphs_), recurse_func (nullptr), nesting_level_left (nesting_level_left_), visited_lookups (visited_lookups_), inactive_lookups (inactive_lookups_), lookup_count (0) {} void set_recurse_func (recurse_func_t func) { recurse_func = func; } private: hb_set_t *visited_lookups; hb_set_t *inactive_lookups; unsigned int lookup_count; }; struct hb_would_apply_context_t : hb_dispatch_context_t { template return_t dispatch (const T &obj) { return obj.would_apply (this); } static return_t default_return_value () { return false; } bool stop_sublookup_iteration (return_t r) const { return r; } hb_face_t *face; const hb_codepoint_t *glyphs; unsigned int len; bool zero_context; hb_would_apply_context_t (hb_face_t *face_, const hb_codepoint_t *glyphs_, unsigned int len_, bool zero_context_) : face (face_), glyphs (glyphs_), len (len_), zero_context (zero_context_) {} }; struct hb_collect_glyphs_context_t : hb_dispatch_context_t { typedef return_t (*recurse_func_t) (hb_collect_glyphs_context_t *c, unsigned int lookup_index); template return_t dispatch (const T &obj) { obj.collect_glyphs (this); return hb_empty_t (); } static return_t default_return_value () { return hb_empty_t (); } void recurse (unsigned int lookup_index) { if (unlikely (nesting_level_left == 0 || !recurse_func)) return; /* Note that GPOS sets recurse_func to nullptr already, so it doesn't get * past the previous check. For GSUB, we only want to collect the output * glyphs in the recursion. If output is not requested, we can go home now. * * Note further, that the above is not exactly correct. A recursed lookup * is allowed to match input that is not matched in the context, but that's * not how most fonts are built. It's possible to relax that and recurse * with all sets here if it proves to be an issue. */ if (output == hb_set_get_empty ()) return; /* Return if new lookup was recursed to before. */ if (recursed_lookups->has (lookup_index)) return; hb_set_t *old_before = before; hb_set_t *old_input = input; hb_set_t *old_after = after; before = input = after = hb_set_get_empty (); nesting_level_left--; recurse_func (this, lookup_index); nesting_level_left++; before = old_before; input = old_input; after = old_after; recursed_lookups->add (lookup_index); } hb_face_t *face; hb_set_t *before; hb_set_t *input; hb_set_t *after; hb_set_t *output; recurse_func_t recurse_func; hb_set_t *recursed_lookups; unsigned int nesting_level_left; hb_collect_glyphs_context_t (hb_face_t *face_, hb_set_t *glyphs_before, /* OUT. May be NULL */ hb_set_t *glyphs_input, /* OUT. May be NULL */ hb_set_t *glyphs_after, /* OUT. May be NULL */ hb_set_t *glyphs_output, /* OUT. May be NULL */ unsigned int nesting_level_left_ = HB_MAX_NESTING_LEVEL) : face (face_), before (glyphs_before ? glyphs_before : hb_set_get_empty ()), input (glyphs_input ? glyphs_input : hb_set_get_empty ()), after (glyphs_after ? glyphs_after : hb_set_get_empty ()), output (glyphs_output ? glyphs_output : hb_set_get_empty ()), recurse_func (nullptr), recursed_lookups (hb_set_create ()), nesting_level_left (nesting_level_left_) {} ~hb_collect_glyphs_context_t () { hb_set_destroy (recursed_lookups); } void set_recurse_func (recurse_func_t func) { recurse_func = func; } }; template struct hb_collect_coverage_context_t : hb_dispatch_context_t, const Coverage &> { typedef const Coverage &return_t; // Stoopid that we have to dupe this here. template return_t dispatch (const T &obj) { return obj.get_coverage (); } static return_t default_return_value () { return Null (Coverage); } bool stop_sublookup_iteration (return_t r) const { r.collect_coverage (set); return false; } hb_collect_coverage_context_t (set_t *set_) : set (set_) {} set_t *set; }; struct hb_ot_apply_context_t : hb_dispatch_context_t { struct matcher_t { matcher_t () : lookup_props (0), mask (-1), ignore_zwnj (false), ignore_zwj (false), per_syllable (false), syllable {0}, match_func (nullptr), match_data (nullptr) {} typedef bool (*match_func_t) (hb_codepoint_t glyph_id, const HBUINT16 &value, const void *data); void set_ignore_zwnj (bool ignore_zwnj_) { ignore_zwnj = ignore_zwnj_; } void set_ignore_zwj (bool ignore_zwj_) { ignore_zwj = ignore_zwj_; } void set_lookup_props (unsigned int lookup_props_) { lookup_props = lookup_props_; } void set_mask (hb_mask_t mask_) { mask = mask_; } void set_per_syllable (bool per_syllable_) { per_syllable = per_syllable_; } void set_syllable (uint8_t syllable_) { syllable = per_syllable ? syllable_ : 0; } void set_match_func (match_func_t match_func_, const void *match_data_) { match_func = match_func_; match_data = match_data_; } enum may_match_t { MATCH_NO, MATCH_YES, MATCH_MAYBE }; may_match_t may_match (const hb_glyph_info_t &info, const HBUINT16 *glyph_data) const { if (!(info.mask & mask) || (syllable && syllable != info.syllable ())) return MATCH_NO; if (match_func) return match_func (info.codepoint, *glyph_data, match_data) ? MATCH_YES : MATCH_NO; return MATCH_MAYBE; } enum may_skip_t { SKIP_NO, SKIP_YES, SKIP_MAYBE }; may_skip_t may_skip (const hb_ot_apply_context_t *c, const hb_glyph_info_t &info) const { if (!c->check_glyph_property (&info, lookup_props)) return SKIP_YES; if (unlikely (_hb_glyph_info_is_default_ignorable_and_not_hidden (&info) && (ignore_zwnj || !_hb_glyph_info_is_zwnj (&info)) && (ignore_zwj || !_hb_glyph_info_is_zwj (&info)))) return SKIP_MAYBE; return SKIP_NO; } protected: unsigned int lookup_props; hb_mask_t mask; bool ignore_zwnj; bool ignore_zwj; bool per_syllable; uint8_t syllable; match_func_t match_func; const void *match_data; }; struct skipping_iterator_t { void init (hb_ot_apply_context_t *c_, bool context_match = false) { c = c_; match_glyph_data = nullptr; matcher.set_match_func (nullptr, nullptr); matcher.set_lookup_props (c->lookup_props); /* Ignore ZWNJ if we are matching GPOS, or matching GSUB context and asked to. */ matcher.set_ignore_zwnj (c->table_index == 1 || (context_match && c->auto_zwnj)); /* Ignore ZWJ if we are matching context, or asked to. */ matcher.set_ignore_zwj (context_match || c->auto_zwj); matcher.set_mask (context_match ? -1 : c->lookup_mask); matcher.set_per_syllable (c->per_syllable); } void set_lookup_props (unsigned int lookup_props) { matcher.set_lookup_props (lookup_props); } void set_match_func (matcher_t::match_func_t match_func_, const void *match_data_, const HBUINT16 glyph_data[]) { matcher.set_match_func (match_func_, match_data_); match_glyph_data = glyph_data; } void reset (unsigned int start_index_, unsigned int num_items_) { idx = start_index_; num_items = num_items_; end = c->buffer->len; matcher.set_syllable (start_index_ == c->buffer->idx ? c->buffer->cur().syllable () : 0); } void reject () { num_items++; if (match_glyph_data) match_glyph_data--; } matcher_t::may_skip_t may_skip (const hb_glyph_info_t &info) const { return matcher.may_skip (c, info); } bool next (unsigned *unsafe_to = nullptr) { assert (num_items > 0); while (idx + num_items < end) { idx++; const hb_glyph_info_t &info = c->buffer->info[idx]; matcher_t::may_skip_t skip = matcher.may_skip (c, info); if (unlikely (skip == matcher_t::SKIP_YES)) continue; matcher_t::may_match_t match = matcher.may_match (info, match_glyph_data); if (match == matcher_t::MATCH_YES || (match == matcher_t::MATCH_MAYBE && skip == matcher_t::SKIP_NO)) { num_items--; if (match_glyph_data) match_glyph_data++; return true; } if (skip == matcher_t::SKIP_NO) { if (unsafe_to) *unsafe_to = idx + 1; return false; } } if (unsafe_to) *unsafe_to = end; return false; } bool prev (unsigned *unsafe_from = nullptr) { assert (num_items > 0); while (idx > num_items - 1) { idx--; const hb_glyph_info_t &info = c->buffer->out_info[idx]; matcher_t::may_skip_t skip = matcher.may_skip (c, info); if (unlikely (skip == matcher_t::SKIP_YES)) continue; matcher_t::may_match_t match = matcher.may_match (info, match_glyph_data); if (match == matcher_t::MATCH_YES || (match == matcher_t::MATCH_MAYBE && skip == matcher_t::SKIP_NO)) { num_items--; if (match_glyph_data) match_glyph_data++; return true; } if (skip == matcher_t::SKIP_NO) { if (unsafe_from) *unsafe_from = hb_max (1u, idx) - 1u; return false; } } if (unsafe_from) *unsafe_from = 0; return false; } unsigned int idx; protected: hb_ot_apply_context_t *c; matcher_t matcher; const HBUINT16 *match_glyph_data; unsigned int num_items; unsigned int end; }; const char *get_name () { return "APPLY"; } typedef return_t (*recurse_func_t) (hb_ot_apply_context_t *c, unsigned int lookup_index); template return_t dispatch (const T &obj) { return obj.apply (this); } static return_t default_return_value () { return false; } bool stop_sublookup_iteration (return_t r) const { return r; } return_t recurse (unsigned int sub_lookup_index) { if (unlikely (nesting_level_left == 0 || !recurse_func || buffer->max_ops-- <= 0)) return default_return_value (); nesting_level_left--; bool ret = recurse_func (this, sub_lookup_index); nesting_level_left++; return ret; } skipping_iterator_t iter_input, iter_context; hb_font_t *font; hb_face_t *face; hb_buffer_t *buffer; recurse_func_t recurse_func; const GDEF &gdef; const VariationStore &var_store; hb_direction_t direction; hb_mask_t lookup_mask; unsigned int table_index; /* GSUB/GPOS */ unsigned int lookup_index; unsigned int lookup_props; unsigned int nesting_level_left; bool has_glyph_classes; bool auto_zwnj; bool auto_zwj; bool per_syllable; bool random; uint32_t random_state; hb_ot_apply_context_t (unsigned int table_index_, hb_font_t *font_, hb_buffer_t *buffer_) : iter_input (), iter_context (), font (font_), face (font->face), buffer (buffer_), recurse_func (nullptr), gdef ( #ifndef HB_NO_OT_LAYOUT *face->table.GDEF->table #else Null (GDEF) #endif ), var_store (gdef.get_var_store ()), direction (buffer_->props.direction), lookup_mask (1), table_index (table_index_), lookup_index ((unsigned int) -1), lookup_props (0), nesting_level_left (HB_MAX_NESTING_LEVEL), has_glyph_classes (gdef.has_glyph_classes ()), auto_zwnj (true), auto_zwj (true), per_syllable (false), random (false), random_state (1) { init_iters (); } void init_iters () { iter_input.init (this, false); iter_context.init (this, true); } void set_lookup_mask (hb_mask_t mask) { lookup_mask = mask; init_iters (); } void set_auto_zwj (bool auto_zwj_) { auto_zwj = auto_zwj_; init_iters (); } void set_auto_zwnj (bool auto_zwnj_) { auto_zwnj = auto_zwnj_; init_iters (); } void set_per_syllable (bool per_syllable_) { per_syllable = per_syllable_; init_iters (); } void set_random (bool random_) { random = random_; } void set_recurse_func (recurse_func_t func) { recurse_func = func; } void set_lookup_index (unsigned int lookup_index_) { lookup_index = lookup_index_; } void set_lookup_props (unsigned int lookup_props_) { lookup_props = lookup_props_; init_iters (); } uint32_t random_number () { /* http://www.cplusplus.com/reference/random/minstd_rand/ */ random_state = random_state * 48271 % 2147483647; return random_state; } bool match_properties_mark (hb_codepoint_t glyph, unsigned int glyph_props, unsigned int match_props) const { /* If using mark filtering sets, the high short of * match_props has the set index. */ if (match_props & LookupFlag::UseMarkFilteringSet) return gdef.mark_set_covers (match_props >> 16, glyph); /* The second byte of match_props has the meaning * "ignore marks of attachment type different than * the attachment type specified." */ if (match_props & LookupFlag::MarkAttachmentType) return (match_props & LookupFlag::MarkAttachmentType) == (glyph_props & LookupFlag::MarkAttachmentType); return true; } bool check_glyph_property (const hb_glyph_info_t *info, unsigned int match_props) const { hb_codepoint_t glyph = info->codepoint; unsigned int glyph_props = _hb_glyph_info_get_glyph_props (info); /* Not covered, if, for example, glyph class is ligature and * match_props includes LookupFlags::IgnoreLigatures */ if (glyph_props & match_props & LookupFlag::IgnoreFlags) return false; if (unlikely (glyph_props & HB_OT_LAYOUT_GLYPH_PROPS_MARK)) return match_properties_mark (glyph, glyph_props, match_props); return true; } void _set_glyph_class (hb_codepoint_t glyph_index, unsigned int class_guess = 0, bool ligature = false, bool component = false) const { unsigned int props = _hb_glyph_info_get_glyph_props (&buffer->cur()); props |= HB_OT_LAYOUT_GLYPH_PROPS_SUBSTITUTED; if (ligature) { props |= HB_OT_LAYOUT_GLYPH_PROPS_LIGATED; /* In the only place that the MULTIPLIED bit is used, Uniscribe * seems to only care about the "last" transformation between * Ligature and Multiple substitutions. Ie. if you ligate, expand, * and ligate again, it forgives the multiplication and acts as * if only ligation happened. As such, clear MULTIPLIED bit. */ props &= ~HB_OT_LAYOUT_GLYPH_PROPS_MULTIPLIED; } if (component) props |= HB_OT_LAYOUT_GLYPH_PROPS_MULTIPLIED; if (likely (has_glyph_classes)) { props &= HB_OT_LAYOUT_GLYPH_PROPS_PRESERVE; _hb_glyph_info_set_glyph_props (&buffer->cur(), props | gdef.get_glyph_props (glyph_index)); } else if (class_guess) { props &= HB_OT_LAYOUT_GLYPH_PROPS_PRESERVE; _hb_glyph_info_set_glyph_props (&buffer->cur(), props | class_guess); } else _hb_glyph_info_set_glyph_props (&buffer->cur(), props); } void replace_glyph (hb_codepoint_t glyph_index) const { _set_glyph_class (glyph_index); (void) buffer->replace_glyph (glyph_index); } void replace_glyph_inplace (hb_codepoint_t glyph_index) const { _set_glyph_class (glyph_index); buffer->cur().codepoint = glyph_index; } void replace_glyph_with_ligature (hb_codepoint_t glyph_index, unsigned int class_guess) const { _set_glyph_class (glyph_index, class_guess, true); (void) buffer->replace_glyph (glyph_index); } void output_glyph_for_component (hb_codepoint_t glyph_index, unsigned int class_guess) const { _set_glyph_class (glyph_index, class_guess, false, true); (void) buffer->output_glyph (glyph_index); } }; struct hb_get_subtables_context_t : hb_dispatch_context_t { template static inline bool apply_to (const void *obj, OT::hb_ot_apply_context_t *c) { const Type *typed_obj = (const Type *) obj; return typed_obj->apply (c); } typedef bool (*hb_apply_func_t) (const void *obj, OT::hb_ot_apply_context_t *c); struct hb_applicable_t { template void init (const T &obj_, hb_apply_func_t apply_func_) { obj = &obj_; apply_func = apply_func_; digest.init (); obj_.get_coverage ().collect_coverage (&digest); } bool apply (OT::hb_ot_apply_context_t *c) const { return digest.may_have (c->buffer->cur().codepoint) && apply_func (obj, c); } private: const void *obj; hb_apply_func_t apply_func; hb_set_digest_t digest; }; typedef hb_vector_t array_t; /* Dispatch interface. */ template return_t dispatch (const T &obj) { hb_applicable_t *entry = array.push(); entry->init (obj, apply_to); return hb_empty_t (); } static return_t default_return_value () { return hb_empty_t (); } hb_get_subtables_context_t (array_t &array_) : array (array_) {} array_t &array; }; typedef bool (*intersects_func_t) (const hb_set_t *glyphs, const HBUINT16 &value, const void *data); typedef void (*intersected_glyphs_func_t) (const hb_set_t *glyphs, const void *data, unsigned value, hb_set_t *intersected_glyphs); typedef void (*collect_glyphs_func_t) (hb_set_t *glyphs, const HBUINT16 &value, const void *data); typedef bool (*match_func_t) (hb_codepoint_t glyph_id, const HBUINT16 &value, const void *data); struct ContextClosureFuncs { intersects_func_t intersects; intersected_glyphs_func_t intersected_glyphs; }; struct ContextCollectGlyphsFuncs { collect_glyphs_func_t collect; }; struct ContextApplyFuncs { match_func_t match; }; static inline bool intersects_glyph (const hb_set_t *glyphs, const HBUINT16 &value, const void *data HB_UNUSED) { return glyphs->has (value); } static inline bool intersects_class (const hb_set_t *glyphs, const HBUINT16 &value, const void *data) { const ClassDef &class_def = *reinterpret_cast(data); return class_def.intersects_class (glyphs, value); } static inline bool intersects_coverage (const hb_set_t *glyphs, const HBUINT16 &value, const void *data) { const Offset16To &coverage = (const Offset16To&)value; return (data+coverage).intersects (glyphs); } static inline void intersected_glyph (const hb_set_t *glyphs HB_UNUSED, const void *data, unsigned value, hb_set_t *intersected_glyphs) { unsigned g = reinterpret_cast(data)[value]; intersected_glyphs->add (g); } static inline void intersected_class_glyphs (const hb_set_t *glyphs, const void *data, unsigned value, hb_set_t *intersected_glyphs) { const ClassDef &class_def = *reinterpret_cast(data); class_def.intersected_class_glyphs (glyphs, value, intersected_glyphs); } static inline void intersected_coverage_glyphs (const hb_set_t *glyphs, const void *data, unsigned value, hb_set_t *intersected_glyphs) { Offset16To coverage; coverage = value; (data+coverage).intersected_coverage_glyphs (glyphs, intersected_glyphs); } static inline bool array_is_subset_of (const hb_set_t *glyphs, unsigned int count, const HBUINT16 values[], intersects_func_t intersects_func, const void *intersects_data) { for (const HBUINT16 &_ : + hb_iter (values, count)) if (!intersects_func (glyphs, _, intersects_data)) return false; return true; } static inline void collect_glyph (hb_set_t *glyphs, const HBUINT16 &value, const void *data HB_UNUSED) { glyphs->add (value); } static inline void collect_class (hb_set_t *glyphs, const HBUINT16 &value, const void *data) { const ClassDef &class_def = *reinterpret_cast(data); class_def.collect_class (glyphs, value); } static inline void collect_coverage (hb_set_t *glyphs, const HBUINT16 &value, const void *data) { const Offset16To &coverage = (const Offset16To&)value; (data+coverage).collect_coverage (glyphs); } static inline void collect_array (hb_collect_glyphs_context_t *c HB_UNUSED, hb_set_t *glyphs, unsigned int count, const HBUINT16 values[], collect_glyphs_func_t collect_func, const void *collect_data) { return + hb_iter (values, count) | hb_apply ([&] (const HBUINT16 &_) { collect_func (glyphs, _, collect_data); }) ; } static inline bool match_glyph (hb_codepoint_t glyph_id, const HBUINT16 &value, const void *data HB_UNUSED) { return glyph_id == value; } static inline bool match_class (hb_codepoint_t glyph_id, const HBUINT16 &value, const void *data) { const ClassDef &class_def = *reinterpret_cast(data); return class_def.get_class (glyph_id) == value; } static inline bool match_coverage (hb_codepoint_t glyph_id, const HBUINT16 &value, const void *data) { const Offset16To &coverage = (const Offset16To&)value; return (data+coverage).get_coverage (glyph_id) != NOT_COVERED; } static inline bool would_match_input (hb_would_apply_context_t *c, unsigned int count, /* Including the first glyph (not matched) */ const HBUINT16 input[], /* Array of input values--start with second glyph */ match_func_t match_func, const void *match_data) { if (count != c->len) return false; for (unsigned int i = 1; i < count; i++) if (likely (!match_func (c->glyphs[i], input[i - 1], match_data))) return false; return true; } static inline bool match_input (hb_ot_apply_context_t *c, unsigned int count, /* Including the first glyph (not matched) */ const HBUINT16 input[], /* Array of input values--start with second glyph */ match_func_t match_func, const void *match_data, unsigned int *end_position, unsigned int match_positions[HB_MAX_CONTEXT_LENGTH], unsigned int *p_total_component_count = nullptr) { TRACE_APPLY (nullptr); if (unlikely (count > HB_MAX_CONTEXT_LENGTH)) return_trace (false); hb_buffer_t *buffer = c->buffer; hb_ot_apply_context_t::skipping_iterator_t &skippy_iter = c->iter_input; skippy_iter.reset (buffer->idx, count - 1); skippy_iter.set_match_func (match_func, match_data, input); /* * This is perhaps the trickiest part of OpenType... Remarks: * * - If all components of the ligature were marks, we call this a mark ligature. * * - If there is no GDEF, and the ligature is NOT a mark ligature, we categorize * it as a ligature glyph. * * - Ligatures cannot be formed across glyphs attached to different components * of previous ligatures. Eg. the sequence is LAM,SHADDA,LAM,FATHA,HEH, and * LAM,LAM,HEH form a ligature, leaving SHADDA,FATHA next to eachother. * However, it would be wrong to ligate that SHADDA,FATHA sequence. * There are a couple of exceptions to this: * * o If a ligature tries ligating with marks that belong to it itself, go ahead, * assuming that the font designer knows what they are doing (otherwise it can * break Indic stuff when a matra wants to ligate with a conjunct, * * o If two marks want to ligate and they belong to different components of the * same ligature glyph, and said ligature glyph is to be ignored according to * mark-filtering rules, then allow. * https://github.com/harfbuzz/harfbuzz/issues/545 */ unsigned int total_component_count = 0; total_component_count += _hb_glyph_info_get_lig_num_comps (&buffer->cur()); unsigned int first_lig_id = _hb_glyph_info_get_lig_id (&buffer->cur()); unsigned int first_lig_comp = _hb_glyph_info_get_lig_comp (&buffer->cur()); enum { LIGBASE_NOT_CHECKED, LIGBASE_MAY_NOT_SKIP, LIGBASE_MAY_SKIP } ligbase = LIGBASE_NOT_CHECKED; match_positions[0] = buffer->idx; for (unsigned int i = 1; i < count; i++) { unsigned unsafe_to; if (!skippy_iter.next (&unsafe_to)) { *end_position = unsafe_to; return_trace (false); } match_positions[i] = skippy_iter.idx; unsigned int this_lig_id = _hb_glyph_info_get_lig_id (&buffer->info[skippy_iter.idx]); unsigned int this_lig_comp = _hb_glyph_info_get_lig_comp (&buffer->info[skippy_iter.idx]); if (first_lig_id && first_lig_comp) { /* If first component was attached to a previous ligature component, * all subsequent components should be attached to the same ligature * component, otherwise we shouldn't ligate them... */ if (first_lig_id != this_lig_id || first_lig_comp != this_lig_comp) { /* ...unless, we are attached to a base ligature and that base * ligature is ignorable. */ if (ligbase == LIGBASE_NOT_CHECKED) { bool found = false; const auto *out = buffer->out_info; unsigned int j = buffer->out_len; while (j && _hb_glyph_info_get_lig_id (&out[j - 1]) == first_lig_id) { if (_hb_glyph_info_get_lig_comp (&out[j - 1]) == 0) { j--; found = true; break; } j--; } if (found && skippy_iter.may_skip (out[j]) == hb_ot_apply_context_t::matcher_t::SKIP_YES) ligbase = LIGBASE_MAY_SKIP; else ligbase = LIGBASE_MAY_NOT_SKIP; } if (ligbase == LIGBASE_MAY_NOT_SKIP) return_trace (false); } } else { /* If first component was NOT attached to a previous ligature component, * all subsequent components should also NOT be attached to any ligature * component, unless they are attached to the first component itself! */ if (this_lig_id && this_lig_comp && (this_lig_id != first_lig_id)) return_trace (false); } total_component_count += _hb_glyph_info_get_lig_num_comps (&buffer->info[skippy_iter.idx]); } *end_position = skippy_iter.idx + 1; if (p_total_component_count) *p_total_component_count = total_component_count; return_trace (true); } static inline bool ligate_input (hb_ot_apply_context_t *c, unsigned int count, /* Including the first glyph */ const unsigned int match_positions[HB_MAX_CONTEXT_LENGTH], /* Including the first glyph */ unsigned int match_end, hb_codepoint_t lig_glyph, unsigned int total_component_count) { TRACE_APPLY (nullptr); hb_buffer_t *buffer = c->buffer; buffer->merge_clusters (buffer->idx, match_end); /* - If a base and one or more marks ligate, consider that as a base, NOT * ligature, such that all following marks can still attach to it. * https://github.com/harfbuzz/harfbuzz/issues/1109 * * - If all components of the ligature were marks, we call this a mark ligature. * If it *is* a mark ligature, we don't allocate a new ligature id, and leave * the ligature to keep its old ligature id. This will allow it to attach to * a base ligature in GPOS. Eg. if the sequence is: LAM,LAM,SHADDA,FATHA,HEH, * and LAM,LAM,HEH for a ligature, they will leave SHADDA and FATHA with a * ligature id and component value of 2. Then if SHADDA,FATHA form a ligature * later, we don't want them to lose their ligature id/component, otherwise * GPOS will fail to correctly position the mark ligature on top of the * LAM,LAM,HEH ligature. See: * https://bugzilla.gnome.org/show_bug.cgi?id=676343 * * - If a ligature is formed of components that some of which are also ligatures * themselves, and those ligature components had marks attached to *their* * components, we have to attach the marks to the new ligature component * positions! Now *that*'s tricky! And these marks may be following the * last component of the whole sequence, so we should loop forward looking * for them and update them. * * Eg. the sequence is LAM,LAM,SHADDA,FATHA,HEH, and the font first forms a * 'calt' ligature of LAM,HEH, leaving the SHADDA and FATHA with a ligature * id and component == 1. Now, during 'liga', the LAM and the LAM-HEH ligature * form a LAM-LAM-HEH ligature. We need to reassign the SHADDA and FATHA to * the new ligature with a component value of 2. * * This in fact happened to a font... See: * https://bugzilla.gnome.org/show_bug.cgi?id=437633 */ bool is_base_ligature = _hb_glyph_info_is_base_glyph (&buffer->info[match_positions[0]]); bool is_mark_ligature = _hb_glyph_info_is_mark (&buffer->info[match_positions[0]]); for (unsigned int i = 1; i < count; i++) if (!_hb_glyph_info_is_mark (&buffer->info[match_positions[i]])) { is_base_ligature = false; is_mark_ligature = false; break; } bool is_ligature = !is_base_ligature && !is_mark_ligature; unsigned int klass = is_ligature ? HB_OT_LAYOUT_GLYPH_PROPS_LIGATURE : 0; unsigned int lig_id = is_ligature ? _hb_allocate_lig_id (buffer) : 0; unsigned int last_lig_id = _hb_glyph_info_get_lig_id (&buffer->cur()); unsigned int last_num_components = _hb_glyph_info_get_lig_num_comps (&buffer->cur()); unsigned int components_so_far = last_num_components; if (is_ligature) { _hb_glyph_info_set_lig_props_for_ligature (&buffer->cur(), lig_id, total_component_count); if (_hb_glyph_info_get_general_category (&buffer->cur()) == HB_UNICODE_GENERAL_CATEGORY_NON_SPACING_MARK) { _hb_glyph_info_set_general_category (&buffer->cur(), HB_UNICODE_GENERAL_CATEGORY_OTHER_LETTER); } } c->replace_glyph_with_ligature (lig_glyph, klass); for (unsigned int i = 1; i < count; i++) { while (buffer->idx < match_positions[i] && buffer->successful) { if (is_ligature) { unsigned int this_comp = _hb_glyph_info_get_lig_comp (&buffer->cur()); if (this_comp == 0) this_comp = last_num_components; unsigned int new_lig_comp = components_so_far - last_num_components + hb_min (this_comp, last_num_components); _hb_glyph_info_set_lig_props_for_mark (&buffer->cur(), lig_id, new_lig_comp); } (void) buffer->next_glyph (); } last_lig_id = _hb_glyph_info_get_lig_id (&buffer->cur()); last_num_components = _hb_glyph_info_get_lig_num_comps (&buffer->cur()); components_so_far += last_num_components; /* Skip the base glyph */ buffer->idx++; } if (!is_mark_ligature && last_lig_id) { /* Re-adjust components for any marks following. */ for (unsigned i = buffer->idx; i < buffer->len; ++i) { if (last_lig_id != _hb_glyph_info_get_lig_id (&buffer->info[i])) break; unsigned this_comp = _hb_glyph_info_get_lig_comp (&buffer->info[i]); if (!this_comp) break; unsigned new_lig_comp = components_so_far - last_num_components + hb_min (this_comp, last_num_components); _hb_glyph_info_set_lig_props_for_mark (&buffer->info[i], lig_id, new_lig_comp); } } return_trace (true); } static inline bool match_backtrack (hb_ot_apply_context_t *c, unsigned int count, const HBUINT16 backtrack[], match_func_t match_func, const void *match_data, unsigned int *match_start) { TRACE_APPLY (nullptr); hb_ot_apply_context_t::skipping_iterator_t &skippy_iter = c->iter_context; skippy_iter.reset (c->buffer->backtrack_len (), count); skippy_iter.set_match_func (match_func, match_data, backtrack); for (unsigned int i = 0; i < count; i++) { unsigned unsafe_from; if (!skippy_iter.prev (&unsafe_from)) { *match_start = unsafe_from; return_trace (false); } } *match_start = skippy_iter.idx; return_trace (true); } static inline bool match_lookahead (hb_ot_apply_context_t *c, unsigned int count, const HBUINT16 lookahead[], match_func_t match_func, const void *match_data, unsigned int start_index, unsigned int *end_index) { TRACE_APPLY (nullptr); hb_ot_apply_context_t::skipping_iterator_t &skippy_iter = c->iter_context; skippy_iter.reset (start_index - 1, count); skippy_iter.set_match_func (match_func, match_data, lookahead); for (unsigned int i = 0; i < count; i++) { unsigned unsafe_to; if (!skippy_iter.next (&unsafe_to)) { *end_index = unsafe_to; return_trace (false); } } *end_index = skippy_iter.idx + 1; return_trace (true); } struct LookupRecord { bool serialize (hb_serialize_context_t *c, const hb_map_t *lookup_map) const { TRACE_SERIALIZE (this); auto *out = c->embed (*this); if (unlikely (!out)) return_trace (false); return_trace (c->check_assign (out->lookupListIndex, lookup_map->get (lookupListIndex), HB_SERIALIZE_ERROR_INT_OVERFLOW)); } bool sanitize (hb_sanitize_context_t *c) const { TRACE_SANITIZE (this); return_trace (c->check_struct (this)); } HBUINT16 sequenceIndex; /* Index into current glyph * sequence--first glyph = 0 */ HBUINT16 lookupListIndex; /* Lookup to apply to that * position--zero--based */ public: DEFINE_SIZE_STATIC (4); }; static unsigned serialize_lookuprecord_array (hb_serialize_context_t *c, const hb_array_t lookupRecords, const hb_map_t *lookup_map) { unsigned count = 0; for (const LookupRecord& r : lookupRecords) { if (!lookup_map->has (r.lookupListIndex)) continue; if (!r.serialize (c, lookup_map)) return 0; count++; } return count; } enum ContextFormat { SimpleContext = 1, ClassBasedContext = 2, CoverageBasedContext = 3 }; static void context_closure_recurse_lookups (hb_closure_context_t *c, unsigned inputCount, const HBUINT16 input[], unsigned lookupCount, const LookupRecord lookupRecord[] /* Array of LookupRecords--in design order */, unsigned value, ContextFormat context_format, const void *data, intersected_glyphs_func_t intersected_glyphs_func) { hb_set_t *covered_seq_indicies = hb_set_create (); for (unsigned int i = 0; i < lookupCount; i++) { unsigned seqIndex = lookupRecord[i].sequenceIndex; if (seqIndex >= inputCount) continue; bool has_pos_glyphs = false; hb_set_t pos_glyphs; if (hb_set_is_empty (covered_seq_indicies) || !hb_set_has (covered_seq_indicies, seqIndex)) { has_pos_glyphs = true; if (seqIndex == 0) { switch (context_format) { case ContextFormat::SimpleContext: pos_glyphs.add (value); break; case ContextFormat::ClassBasedContext: intersected_glyphs_func (&c->parent_active_glyphs (), data, value, &pos_glyphs); break; case ContextFormat::CoverageBasedContext: pos_glyphs.set (c->parent_active_glyphs ()); break; } } else { const void *input_data = input; unsigned input_value = seqIndex - 1; if (context_format != ContextFormat::SimpleContext) { input_data = data; input_value = input[seqIndex - 1]; } intersected_glyphs_func (c->glyphs, input_data, input_value, &pos_glyphs); } } covered_seq_indicies->add (seqIndex); if (has_pos_glyphs) { c->push_cur_active_glyphs () = pos_glyphs; } else { c->push_cur_active_glyphs ().set (*c->glyphs); } unsigned endIndex = inputCount; if (context_format == ContextFormat::CoverageBasedContext) endIndex += 1; c->recurse (lookupRecord[i].lookupListIndex, covered_seq_indicies, seqIndex, endIndex); c->pop_cur_done_glyphs (); } hb_set_destroy (covered_seq_indicies); } template static inline void recurse_lookups (context_t *c, unsigned int lookupCount, const LookupRecord lookupRecord[] /* Array of LookupRecords--in design order */) { for (unsigned int i = 0; i < lookupCount; i++) c->recurse (lookupRecord[i].lookupListIndex); } static inline void apply_lookup (hb_ot_apply_context_t *c, unsigned int count, /* Including the first glyph */ unsigned int match_positions[HB_MAX_CONTEXT_LENGTH], /* Including the first glyph */ unsigned int lookupCount, const LookupRecord lookupRecord[], /* Array of LookupRecords--in design order */ unsigned int match_end) { hb_buffer_t *buffer = c->buffer; int end; /* All positions are distance from beginning of *output* buffer. * Adjust. */ { unsigned int bl = buffer->backtrack_len (); end = bl + match_end - buffer->idx; int delta = bl - buffer->idx; /* Convert positions to new indexing. */ for (unsigned int j = 0; j < count; j++) match_positions[j] += delta; } for (unsigned int i = 0; i < lookupCount && buffer->successful; i++) { unsigned int idx = lookupRecord[i].sequenceIndex; if (idx >= count) continue; unsigned int orig_len = buffer->backtrack_len () + buffer->lookahead_len (); /* This can happen if earlier recursed lookups deleted many entries. */ if (unlikely (match_positions[idx] >= orig_len)) continue; if (unlikely (!buffer->move_to (match_positions[idx]))) break; if (unlikely (buffer->max_ops <= 0)) break; if (!c->recurse (lookupRecord[i].lookupListIndex)) continue; unsigned int new_len = buffer->backtrack_len () + buffer->lookahead_len (); int delta = new_len - orig_len; if (!delta) continue; /* Recursed lookup changed buffer len. Adjust. * * TODO: * * Right now, if buffer length increased by n, we assume n new glyphs * were added right after the current position, and if buffer length * was decreased by n, we assume n match positions after the current * one where removed. The former (buffer length increased) case is * fine, but the decrease case can be improved in at least two ways, * both of which are significant: * * - If recursed-to lookup is MultipleSubst and buffer length * decreased, then it's current match position that was deleted, * NOT the one after it. * * - If buffer length was decreased by n, it does not necessarily * mean that n match positions where removed, as there recursed-to * lookup might had a different LookupFlag. Here's a constructed * case of that: * https://github.com/harfbuzz/harfbuzz/discussions/3538 * * It should be possible to construct tests for both of these cases. */ end += delta; if (end < int (match_positions[idx])) { /* End might end up being smaller than match_positions[idx] if the recursed * lookup ended up removing many items. * Just never rewind end beyond start of current position, since that is * not possible in the recursed lookup. Also adjust delta as such. * * https://bugs.chromium.org/p/chromium/issues/detail?id=659496 * https://github.com/harfbuzz/harfbuzz/issues/1611 */ delta += match_positions[idx] - end; end = match_positions[idx]; } unsigned int next = idx + 1; /* next now is the position after the recursed lookup. */ if (delta > 0) { if (unlikely (delta + count > HB_MAX_CONTEXT_LENGTH)) break; } else { /* NOTE: delta is non-positive. */ delta = hb_max (delta, (int) next - (int) count); next -= delta; } /* Shift! */ memmove (match_positions + next + delta, match_positions + next, (count - next) * sizeof (match_positions[0])); next += delta; count += delta; /* Fill in new entries. */ for (unsigned int j = idx + 1; j < next; j++) match_positions[j] = match_positions[j - 1] + 1; /* And fixup the rest. */ for (; next < count; next++) match_positions[next] += delta; } (void) buffer->move_to (end); } /* Contextual lookups */ struct ContextClosureLookupContext { ContextClosureFuncs funcs; ContextFormat context_format; const void *intersects_data; }; struct ContextCollectGlyphsLookupContext { ContextCollectGlyphsFuncs funcs; const void *collect_data; }; struct ContextApplyLookupContext { ContextApplyFuncs funcs; const void *match_data; }; static inline bool context_intersects (const hb_set_t *glyphs, unsigned int inputCount, /* Including the first glyph (not matched) */ const HBUINT16 input[], /* Array of input values--start with second glyph */ ContextClosureLookupContext &lookup_context) { return array_is_subset_of (glyphs, inputCount ? inputCount - 1 : 0, input, lookup_context.funcs.intersects, lookup_context.intersects_data); } static inline void context_closure_lookup (hb_closure_context_t *c, unsigned int inputCount, /* Including the first glyph (not matched) */ const HBUINT16 input[], /* Array of input values--start with second glyph */ unsigned int lookupCount, const LookupRecord lookupRecord[], unsigned value, /* Index of first glyph in Coverage or Class value in ClassDef table */ ContextClosureLookupContext &lookup_context) { if (context_intersects (c->glyphs, inputCount, input, lookup_context)) context_closure_recurse_lookups (c, inputCount, input, lookupCount, lookupRecord, value, lookup_context.context_format, lookup_context.intersects_data, lookup_context.funcs.intersected_glyphs); } static inline void context_collect_glyphs_lookup (hb_collect_glyphs_context_t *c, unsigned int inputCount, /* Including the first glyph (not matched) */ const HBUINT16 input[], /* Array of input values--start with second glyph */ unsigned int lookupCount, const LookupRecord lookupRecord[], ContextCollectGlyphsLookupContext &lookup_context) { collect_array (c, c->input, inputCount ? inputCount - 1 : 0, input, lookup_context.funcs.collect, lookup_context.collect_data); recurse_lookups (c, lookupCount, lookupRecord); } static inline bool context_would_apply_lookup (hb_would_apply_context_t *c, unsigned int inputCount, /* Including the first glyph (not matched) */ const HBUINT16 input[], /* Array of input values--start with second glyph */ unsigned int lookupCount HB_UNUSED, const LookupRecord lookupRecord[] HB_UNUSED, ContextApplyLookupContext &lookup_context) { return would_match_input (c, inputCount, input, lookup_context.funcs.match, lookup_context.match_data); } static inline bool context_apply_lookup (hb_ot_apply_context_t *c, unsigned int inputCount, /* Including the first glyph (not matched) */ const HBUINT16 input[], /* Array of input values--start with second glyph */ unsigned int lookupCount, const LookupRecord lookupRecord[], ContextApplyLookupContext &lookup_context) { unsigned match_end = 0; unsigned match_positions[HB_MAX_CONTEXT_LENGTH]; if (match_input (c, inputCount, input, lookup_context.funcs.match, lookup_context.match_data, &match_end, match_positions)) { c->buffer->unsafe_to_break (c->buffer->idx, match_end); apply_lookup (c, inputCount, match_positions, lookupCount, lookupRecord, match_end); return true; } else { c->buffer->unsafe_to_concat (c->buffer->idx, match_end); return false; } } struct Rule { bool intersects (const hb_set_t *glyphs, ContextClosureLookupContext &lookup_context) const { return context_intersects (glyphs, inputCount, inputZ.arrayZ, lookup_context); } void closure (hb_closure_context_t *c, unsigned value, ContextClosureLookupContext &lookup_context) const { if (unlikely (c->lookup_limit_exceeded ())) return; const UnsizedArrayOf &lookupRecord = StructAfter> (inputZ.as_array ((inputCount ? inputCount - 1 : 0))); context_closure_lookup (c, inputCount, inputZ.arrayZ, lookupCount, lookupRecord.arrayZ, value, lookup_context); } void closure_lookups (hb_closure_lookups_context_t *c, ContextClosureLookupContext &lookup_context) const { if (unlikely (c->lookup_limit_exceeded ())) return; if (!intersects (c->glyphs, lookup_context)) return; const UnsizedArrayOf &lookupRecord = StructAfter> (inputZ.as_array (inputCount ? inputCount - 1 : 0)); recurse_lookups (c, lookupCount, lookupRecord.arrayZ); } void collect_glyphs (hb_collect_glyphs_context_t *c, ContextCollectGlyphsLookupContext &lookup_context) const { const UnsizedArrayOf &lookupRecord = StructAfter> (inputZ.as_array (inputCount ? inputCount - 1 : 0)); context_collect_glyphs_lookup (c, inputCount, inputZ.arrayZ, lookupCount, lookupRecord.arrayZ, lookup_context); } bool would_apply (hb_would_apply_context_t *c, ContextApplyLookupContext &lookup_context) const { const UnsizedArrayOf &lookupRecord = StructAfter> (inputZ.as_array (inputCount ? inputCount - 1 : 0)); return context_would_apply_lookup (c, inputCount, inputZ.arrayZ, lookupCount, lookupRecord.arrayZ, lookup_context); } bool apply (hb_ot_apply_context_t *c, ContextApplyLookupContext &lookup_context) const { TRACE_APPLY (this); const UnsizedArrayOf &lookupRecord = StructAfter> (inputZ.as_array (inputCount ? inputCount - 1 : 0)); return_trace (context_apply_lookup (c, inputCount, inputZ.arrayZ, lookupCount, lookupRecord.arrayZ, lookup_context)); } bool serialize (hb_serialize_context_t *c, const hb_map_t *input_mapping, /* old->new glyphid or class mapping */ const hb_map_t *lookup_map) const { TRACE_SERIALIZE (this); auto *out = c->start_embed (this); if (unlikely (!c->extend_min (out))) return_trace (false); out->inputCount = inputCount; const hb_array_t input = inputZ.as_array (inputCount - 1); for (const auto org : input) { HBUINT16 d; d = input_mapping->get (org); c->copy (d); } const UnsizedArrayOf &lookupRecord = StructAfter> (inputZ.as_array ((inputCount ? inputCount - 1 : 0))); unsigned count = serialize_lookuprecord_array (c, lookupRecord.as_array (lookupCount), lookup_map); return_trace (c->check_assign (out->lookupCount, count, HB_SERIALIZE_ERROR_INT_OVERFLOW)); } bool subset (hb_subset_context_t *c, const hb_map_t *lookup_map, const hb_map_t *klass_map = nullptr) const { TRACE_SUBSET (this); if (unlikely (!inputCount)) return_trace (false); const hb_array_t input = inputZ.as_array (inputCount - 1); const hb_map_t *mapping = klass_map == nullptr ? c->plan->glyph_map : klass_map; if (!hb_all (input, mapping)) return_trace (false); return_trace (serialize (c->serializer, mapping, lookup_map)); } public: bool sanitize (hb_sanitize_context_t *c) const { TRACE_SANITIZE (this); return_trace (inputCount.sanitize (c) && lookupCount.sanitize (c) && c->check_range (inputZ.arrayZ, inputZ.item_size * (inputCount ? inputCount - 1 : 0) + LookupRecord::static_size * lookupCount)); } protected: HBUINT16 inputCount; /* Total number of glyphs in input * glyph sequence--includes the first * glyph */ HBUINT16 lookupCount; /* Number of LookupRecords */ UnsizedArrayOf inputZ; /* Array of match inputs--start with * second glyph */ /*UnsizedArrayOf lookupRecordX;*/ /* Array of LookupRecords--in * design order */ public: DEFINE_SIZE_ARRAY (4, inputZ); }; struct RuleSet { bool intersects (const hb_set_t *glyphs, ContextClosureLookupContext &lookup_context) const { return + hb_iter (rule) | hb_map (hb_add (this)) | hb_map ([&] (const Rule &_) { return _.intersects (glyphs, lookup_context); }) | hb_any ; } void closure (hb_closure_context_t *c, unsigned value, ContextClosureLookupContext &lookup_context) const { if (unlikely (c->lookup_limit_exceeded ())) return; return + hb_iter (rule) | hb_map (hb_add (this)) | hb_apply ([&] (const Rule &_) { _.closure (c, value, lookup_context); }) ; } void closure_lookups (hb_closure_lookups_context_t *c, ContextClosureLookupContext &lookup_context) const { if (unlikely (c->lookup_limit_exceeded ())) return; + hb_iter (rule) | hb_map (hb_add (this)) | hb_apply ([&] (const Rule &_) { _.closure_lookups (c, lookup_context); }) ; } void collect_glyphs (hb_collect_glyphs_context_t *c, ContextCollectGlyphsLookupContext &lookup_context) const { return + hb_iter (rule) | hb_map (hb_add (this)) | hb_apply ([&] (const Rule &_) { _.collect_glyphs (c, lookup_context); }) ; } bool would_apply (hb_would_apply_context_t *c, ContextApplyLookupContext &lookup_context) const { return + hb_iter (rule) | hb_map (hb_add (this)) | hb_map ([&] (const Rule &_) { return _.would_apply (c, lookup_context); }) | hb_any ; } bool apply (hb_ot_apply_context_t *c, ContextApplyLookupContext &lookup_context) const { TRACE_APPLY (this); return_trace ( + hb_iter (rule) | hb_map (hb_add (this)) | hb_map ([&] (const Rule &_) { return _.apply (c, lookup_context); }) | hb_any ) ; } bool subset (hb_subset_context_t *c, const hb_map_t *lookup_map, const hb_map_t *klass_map = nullptr) const { TRACE_SUBSET (this); auto snap = c->serializer->snapshot (); auto *out = c->serializer->start_embed (*this); if (unlikely (!c->serializer->extend_min (out))) return_trace (false); for (const Offset16To& _ : rule) { if (!_) continue; auto o_snap = c->serializer->snapshot (); auto *o = out->rule.serialize_append (c->serializer); if (unlikely (!o)) continue; if (!o->serialize_subset (c, _, this, lookup_map, klass_map)) { out->rule.pop (); c->serializer->revert (o_snap); } } bool ret = bool (out->rule); if (!ret) c->serializer->revert (snap); return_trace (ret); } bool sanitize (hb_sanitize_context_t *c) const { TRACE_SANITIZE (this); return_trace (rule.sanitize (c, this)); } protected: Array16OfOffset16To rule; /* Array of Rule tables * ordered by preference */ public: DEFINE_SIZE_ARRAY (2, rule); }; struct ContextFormat1 { bool intersects (const hb_set_t *glyphs) const { struct ContextClosureLookupContext lookup_context = { {intersects_glyph, intersected_glyph}, ContextFormat::SimpleContext, nullptr }; return + hb_zip (this+coverage, ruleSet) | hb_filter (*glyphs, hb_first) | hb_map (hb_second) | hb_map (hb_add (this)) | hb_map ([&] (const RuleSet &_) { return _.intersects (glyphs, lookup_context); }) | hb_any ; } bool may_have_non_1to1 () const { return true; } void closure (hb_closure_context_t *c) const { hb_set_t* cur_active_glyphs = &c->push_cur_active_glyphs (); get_coverage ().intersected_coverage_glyphs (&c->previous_parent_active_glyphs (), cur_active_glyphs); struct ContextClosureLookupContext lookup_context = { {intersects_glyph, intersected_glyph}, ContextFormat::SimpleContext, nullptr }; + hb_zip (this+coverage, hb_range ((unsigned) ruleSet.len)) | hb_filter ([&] (hb_codepoint_t _) { return c->previous_parent_active_glyphs ().has (_); }, hb_first) | hb_map ([&](const hb_pair_t _) { return hb_pair_t (_.first, this+ruleSet[_.second]); }) | hb_apply ([&] (const hb_pair_t& _) { _.second.closure (c, _.first, lookup_context); }) ; c->pop_cur_done_glyphs (); } void closure_lookups (hb_closure_lookups_context_t *c) const { struct ContextClosureLookupContext lookup_context = { {intersects_glyph, intersected_glyph}, ContextFormat::SimpleContext, nullptr }; + hb_zip (this+coverage, ruleSet) | hb_filter (*c->glyphs, hb_first) | hb_map (hb_second) | hb_map (hb_add (this)) | hb_apply ([&] (const RuleSet &_) { _.closure_lookups (c, lookup_context); }) ; } void collect_variation_indices (hb_collect_variation_indices_context_t *c) const {} void collect_glyphs (hb_collect_glyphs_context_t *c) const { (this+coverage).collect_coverage (c->input); struct ContextCollectGlyphsLookupContext lookup_context = { {collect_glyph}, nullptr }; + hb_iter (ruleSet) | hb_map (hb_add (this)) | hb_apply ([&] (const RuleSet &_) { _.collect_glyphs (c, lookup_context); }) ; } bool would_apply (hb_would_apply_context_t *c) const { const RuleSet &rule_set = this+ruleSet[(this+coverage).get_coverage (c->glyphs[0])]; struct ContextApplyLookupContext lookup_context = { {match_glyph}, nullptr }; return rule_set.would_apply (c, lookup_context); } const Coverage &get_coverage () const { return this+coverage; } bool apply (hb_ot_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); const RuleSet &rule_set = this+ruleSet[index]; struct ContextApplyLookupContext lookup_context = { {match_glyph}, nullptr }; return_trace (rule_set.apply (c, lookup_context)); } bool subset (hb_subset_context_t *c) const { TRACE_SUBSET (this); const hb_set_t &glyphset = *c->plan->glyphset_gsub (); const hb_map_t &glyph_map = *c->plan->glyph_map; auto *out = c->serializer->start_embed (*this); if (unlikely (!c->serializer->extend_min (out))) return_trace (false); out->format = format; const hb_map_t *lookup_map = c->table_tag == HB_OT_TAG_GSUB ? c->plan->gsub_lookups : c->plan->gpos_lookups; hb_sorted_vector_t new_coverage; + hb_zip (this+coverage, ruleSet) | hb_filter (glyphset, hb_first) | hb_filter (subset_offset_array (c, out->ruleSet, this, lookup_map), hb_second) | hb_map (hb_first) | hb_map (glyph_map) | hb_sink (new_coverage) ; out->coverage.serialize_serialize (c->serializer, new_coverage.iter ()); return_trace (bool (new_coverage)); } bool sanitize (hb_sanitize_context_t *c) const { TRACE_SANITIZE (this); return_trace (coverage.sanitize (c, this) && ruleSet.sanitize (c, this)); } protected: HBUINT16 format; /* Format identifier--format = 1 */ Offset16To coverage; /* Offset to Coverage table--from * beginning of table */ Array16OfOffset16To ruleSet; /* Array of RuleSet tables * ordered by Coverage Index */ public: DEFINE_SIZE_ARRAY (6, ruleSet); }; struct ContextFormat2 { bool intersects (const hb_set_t *glyphs) const { if (!(this+coverage).intersects (glyphs)) return false; const ClassDef &class_def = this+classDef; struct ContextClosureLookupContext lookup_context = { {intersects_class, intersected_class_glyphs}, ContextFormat::ClassBasedContext, &class_def }; hb_set_t retained_coverage_glyphs; (this+coverage).intersected_coverage_glyphs (glyphs, &retained_coverage_glyphs); hb_set_t coverage_glyph_classes; class_def.intersected_classes (&retained_coverage_glyphs, &coverage_glyph_classes); return + hb_iter (ruleSet) | hb_map (hb_add (this)) | hb_enumerate | hb_map ([&] (const hb_pair_t p) { return class_def.intersects_class (glyphs, p.first) && coverage_glyph_classes.has (p.first) && p.second.intersects (glyphs, lookup_context); }) | hb_any ; } bool may_have_non_1to1 () const { return true; } void closure (hb_closure_context_t *c) const { if (!(this+coverage).intersects (c->glyphs)) return; hb_set_t* cur_active_glyphs = &c->push_cur_active_glyphs (); get_coverage ().intersected_coverage_glyphs (&c->previous_parent_active_glyphs (), cur_active_glyphs); const ClassDef &class_def = this+classDef; struct ContextClosureLookupContext lookup_context = { {intersects_class, intersected_class_glyphs}, ContextFormat::ClassBasedContext, &class_def }; + hb_enumerate (ruleSet) | hb_filter ([&] (unsigned _) { return class_def.intersects_class (&c->parent_active_glyphs (), _); }, hb_first) | hb_apply ([&] (const hb_pair_t&> _) { const RuleSet& rule_set = this+_.second; rule_set.closure (c, _.first, lookup_context); }) ; c->pop_cur_done_glyphs (); } void closure_lookups (hb_closure_lookups_context_t *c) const { if (!(this+coverage).intersects (c->glyphs)) return; const ClassDef &class_def = this+classDef; struct ContextClosureLookupContext lookup_context = { {intersects_class, intersected_class_glyphs}, ContextFormat::ClassBasedContext, &class_def }; + hb_iter (ruleSet) | hb_map (hb_add (this)) | hb_enumerate | hb_filter ([&] (const hb_pair_t p) { return class_def.intersects_class (c->glyphs, p.first); }) | hb_map (hb_second) | hb_apply ([&] (const RuleSet & _) { _.closure_lookups (c, lookup_context); }); } void collect_variation_indices (hb_collect_variation_indices_context_t *c) const {} void collect_glyphs (hb_collect_glyphs_context_t *c) const { (this+coverage).collect_coverage (c->input); const ClassDef &class_def = this+classDef; struct ContextCollectGlyphsLookupContext lookup_context = { {collect_class}, &class_def }; + hb_iter (ruleSet) | hb_map (hb_add (this)) | hb_apply ([&] (const RuleSet &_) { _.collect_glyphs (c, lookup_context); }) ; } bool would_apply (hb_would_apply_context_t *c) const { const ClassDef &class_def = this+classDef; unsigned int index = class_def.get_class (c->glyphs[0]); const RuleSet &rule_set = this+ruleSet[index]; struct ContextApplyLookupContext lookup_context = { {match_class}, &class_def }; return rule_set.would_apply (c, lookup_context); } const Coverage &get_coverage () const { return this+coverage; } bool apply (hb_ot_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); const ClassDef &class_def = this+classDef; index = class_def.get_class (c->buffer->cur().codepoint); const RuleSet &rule_set = this+ruleSet[index]; struct ContextApplyLookupContext lookup_context = { {match_class}, &class_def }; return_trace (rule_set.apply (c, lookup_context)); } bool subset (hb_subset_context_t *c) const { TRACE_SUBSET (this); auto *out = c->serializer->start_embed (*this); if (unlikely (!c->serializer->extend_min (out))) return_trace (false); out->format = format; if (unlikely (!out->coverage.serialize_subset (c, coverage, this))) return_trace (false); hb_map_t klass_map; out->classDef.serialize_subset (c, classDef, this, &klass_map); const hb_set_t* glyphset = c->plan->glyphset_gsub (); hb_set_t retained_coverage_glyphs; (this+coverage).intersected_coverage_glyphs (glyphset, &retained_coverage_glyphs); hb_set_t coverage_glyph_classes; (this+classDef).intersected_classes (&retained_coverage_glyphs, &coverage_glyph_classes); const hb_map_t *lookup_map = c->table_tag == HB_OT_TAG_GSUB ? c->plan->gsub_lookups : c->plan->gpos_lookups; bool ret = true; int non_zero_index = -1, index = 0; for (const auto& _ : + hb_enumerate (ruleSet) | hb_filter (klass_map, hb_first)) { auto *o = out->ruleSet.serialize_append (c->serializer); if (unlikely (!o)) { ret = false; break; } if (coverage_glyph_classes.has (_.first) && o->serialize_subset (c, _.second, this, lookup_map, &klass_map)) non_zero_index = index; index++; } if (!ret || non_zero_index == -1) return_trace (false); //prune empty trailing ruleSets --index; while (index > non_zero_index) { out->ruleSet.pop (); index--; } return_trace (bool (out->ruleSet)); } bool sanitize (hb_sanitize_context_t *c) const { TRACE_SANITIZE (this); return_trace (coverage.sanitize (c, this) && classDef.sanitize (c, this) && ruleSet.sanitize (c, this)); } protected: HBUINT16 format; /* Format identifier--format = 2 */ Offset16To coverage; /* Offset to Coverage table--from * beginning of table */ Offset16To classDef; /* Offset to glyph ClassDef table--from * beginning of table */ Array16OfOffset16To ruleSet; /* Array of RuleSet tables * ordered by class */ public: DEFINE_SIZE_ARRAY (8, ruleSet); }; struct ContextFormat3 { bool intersects (const hb_set_t *glyphs) const { if (!(this+coverageZ[0]).intersects (glyphs)) return false; struct ContextClosureLookupContext lookup_context = { {intersects_coverage, intersected_coverage_glyphs}, ContextFormat::CoverageBasedContext, this }; return context_intersects (glyphs, glyphCount, (const HBUINT16 *) (coverageZ.arrayZ + 1), lookup_context); } bool may_have_non_1to1 () const { return true; } void closure (hb_closure_context_t *c) const { if (!(this+coverageZ[0]).intersects (c->glyphs)) return; hb_set_t* cur_active_glyphs = &c->push_cur_active_glyphs (); get_coverage ().intersected_coverage_glyphs (&c->previous_parent_active_glyphs (), cur_active_glyphs); const LookupRecord *lookupRecord = &StructAfter (coverageZ.as_array (glyphCount)); struct ContextClosureLookupContext lookup_context = { {intersects_coverage, intersected_coverage_glyphs}, ContextFormat::CoverageBasedContext, this }; context_closure_lookup (c, glyphCount, (const HBUINT16 *) (coverageZ.arrayZ + 1), lookupCount, lookupRecord, 0, lookup_context); c->pop_cur_done_glyphs (); } void closure_lookups (hb_closure_lookups_context_t *c) const { if (!intersects (c->glyphs)) return; const LookupRecord *lookupRecord = &StructAfter (coverageZ.as_array (glyphCount)); recurse_lookups (c, lookupCount, lookupRecord); } void collect_variation_indices (hb_collect_variation_indices_context_t *c) const {} void collect_glyphs (hb_collect_glyphs_context_t *c) const { (this+coverageZ[0]).collect_coverage (c->input); const LookupRecord *lookupRecord = &StructAfter (coverageZ.as_array (glyphCount)); struct ContextCollectGlyphsLookupContext lookup_context = { {collect_coverage}, this }; context_collect_glyphs_lookup (c, glyphCount, (const HBUINT16 *) (coverageZ.arrayZ + 1), lookupCount, lookupRecord, lookup_context); } bool would_apply (hb_would_apply_context_t *c) const { const LookupRecord *lookupRecord = &StructAfter (coverageZ.as_array (glyphCount)); struct ContextApplyLookupContext lookup_context = { {match_coverage}, this }; return context_would_apply_lookup (c, glyphCount, (const HBUINT16 *) (coverageZ.arrayZ + 1), lookupCount, lookupRecord, lookup_context); } const Coverage &get_coverage () const { return this+coverageZ[0]; } bool apply (hb_ot_apply_context_t *c) const { TRACE_APPLY (this); unsigned int index = (this+coverageZ[0]).get_coverage (c->buffer->cur().codepoint); if (likely (index == NOT_COVERED)) return_trace (false); const LookupRecord *lookupRecord = &StructAfter (coverageZ.as_array (glyphCount)); struct ContextApplyLookupContext lookup_context = { {match_coverage}, this }; return_trace (context_apply_lookup (c, glyphCount, (const HBUINT16 *) (coverageZ.arrayZ + 1), lookupCount, lookupRecord, lookup_context)); } bool subset (hb_subset_context_t *c) const { TRACE_SUBSET (this); auto *out = c->serializer->start_embed (this); if (unlikely (!c->serializer->extend_min (out))) return_trace (false); out->format = format; out->glyphCount = glyphCount; auto coverages = coverageZ.as_array (glyphCount); for (const Offset16To& offset : coverages) { /* TODO(subset) This looks like should not be necessary to write this way. */ auto *o = c->serializer->allocate_size> (Offset16To::static_size); if (unlikely (!o)) return_trace (false); if (!o->serialize_subset (c, offset, this)) return_trace (false); } const UnsizedArrayOf& lookupRecord = StructAfter> (coverageZ.as_array (glyphCount)); const hb_map_t *lookup_map = c->table_tag == HB_OT_TAG_GSUB ? c->plan->gsub_lookups : c->plan->gpos_lookups; unsigned count = serialize_lookuprecord_array (c->serializer, lookupRecord.as_array (lookupCount), lookup_map); return_trace (c->serializer->check_assign (out->lookupCount, count, HB_SERIALIZE_ERROR_INT_OVERFLOW)); } bool sanitize (hb_sanitize_context_t *c) const { TRACE_SANITIZE (this); if (!c->check_struct (this)) return_trace (false); unsigned int count = glyphCount; if (!count) return_trace (false); /* We want to access coverageZ[0] freely. */ if (!c->check_array (coverageZ.arrayZ, count)) return_trace (false); for (unsigned int i = 0; i < count; i++) if (!coverageZ[i].sanitize (c, this)) return_trace (false); const LookupRecord *lookupRecord = &StructAfter (coverageZ.as_array (glyphCount)); return_trace (c->check_array (lookupRecord, lookupCount)); } protected: HBUINT16 format; /* Format identifier--format = 3 */ HBUINT16 glyphCount; /* Number of glyphs in the input glyph * sequence */ HBUINT16 lookupCount; /* Number of LookupRecords */ UnsizedArrayOf> coverageZ; /* Array of offsets to Coverage * table in glyph sequence order */ /*UnsizedArrayOf lookupRecordX;*/ /* Array of LookupRecords--in * design order */ public: DEFINE_SIZE_ARRAY (6, coverageZ); }; struct Context { template typename context_t::return_t dispatch (context_t *c, Ts&&... ds) 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, std::forward (ds)...)); case 2: return_trace (c->dispatch (u.format2, std::forward (ds)...)); case 3: return_trace (c->dispatch (u.format3, std::forward (ds)...)); default:return_trace (c->default_return_value ()); } } protected: union { HBUINT16 format; /* Format identifier */ ContextFormat1 format1; ContextFormat2 format2; ContextFormat3 format3; } u; }; /* Chaining Contextual lookups */ struct ChainContextClosureLookupContext { ContextClosureFuncs funcs; ContextFormat context_format; const void *intersects_data[3]; }; struct ChainContextCollectGlyphsLookupContext { ContextCollectGlyphsFuncs funcs; const void *collect_data[3]; }; struct ChainContextApplyLookupContext { ContextApplyFuncs funcs; const void *match_data[3]; }; static inline bool chain_context_intersects (const hb_set_t *glyphs, unsigned int backtrackCount, const HBUINT16 backtrack[], unsigned int inputCount, /* Including the first glyph (not matched) */ const HBUINT16 input[], /* Array of input values--start with second glyph */ unsigned int lookaheadCount, const HBUINT16 lookahead[], ChainContextClosureLookupContext &lookup_context) { return array_is_subset_of (glyphs, backtrackCount, backtrack, lookup_context.funcs.intersects, lookup_context.intersects_data[0]) && array_is_subset_of (glyphs, inputCount ? inputCount - 1 : 0, input, lookup_context.funcs.intersects, lookup_context.intersects_data[1]) && array_is_subset_of (glyphs, lookaheadCount, lookahead, lookup_context.funcs.intersects, lookup_context.intersects_data[2]); } static inline void chain_context_closure_lookup (hb_closure_context_t *c, unsigned int backtrackCount, const HBUINT16 backtrack[], unsigned int inputCount, /* Including the first glyph (not matched) */ const HBUINT16 input[], /* Array of input values--start with second glyph */ unsigned int lookaheadCount, const HBUINT16 lookahead[], unsigned int lookupCount, const LookupRecord lookupRecord[], unsigned value, ChainContextClosureLookupContext &lookup_context) { if (chain_context_intersects (c->glyphs, backtrackCount, backtrack, inputCount, input, lookaheadCount, lookahead, lookup_context)) context_closure_recurse_lookups (c, inputCount, input, lookupCount, lookupRecord, value, lookup_context.context_format, lookup_context.intersects_data[1], lookup_context.funcs.intersected_glyphs); } static inline void chain_context_collect_glyphs_lookup (hb_collect_glyphs_context_t *c, unsigned int backtrackCount, const HBUINT16 backtrack[], unsigned int inputCount, /* Including the first glyph (not matched) */ const HBUINT16 input[], /* Array of input values--start with second glyph */ unsigned int lookaheadCount, const HBUINT16 lookahead[], unsigned int lookupCount, const LookupRecord lookupRecord[], ChainContextCollectGlyphsLookupContext &lookup_context) { collect_array (c, c->before, backtrackCount, backtrack, lookup_context.funcs.collect, lookup_context.collect_data[0]); collect_array (c, c->input, inputCount ? inputCount - 1 : 0, input, lookup_context.funcs.collect, lookup_context.collect_data[1]); collect_array (c, c->after, lookaheadCount, lookahead, lookup_context.funcs.collect, lookup_context.collect_data[2]); recurse_lookups (c, lookupCount, lookupRecord); } static inline bool chain_context_would_apply_lookup (hb_would_apply_context_t *c, unsigned int backtrackCount, const HBUINT16 backtrack[] HB_UNUSED, unsigned int inputCount, /* Including the first glyph (not matched) */ const HBUINT16 input[], /* Array of input values--start with second glyph */ unsigned int lookaheadCount, const HBUINT16 lookahead[] HB_UNUSED, unsigned int lookupCount HB_UNUSED, const LookupRecord lookupRecord[] HB_UNUSED, ChainContextApplyLookupContext &lookup_context) { return (c->zero_context ? !backtrackCount && !lookaheadCount : true) && would_match_input (c, inputCount, input, lookup_context.funcs.match, lookup_context.match_data[1]); } static inline bool chain_context_apply_lookup (hb_ot_apply_context_t *c, unsigned int backtrackCount, const HBUINT16 backtrack[], unsigned int inputCount, /* Including the first glyph (not matched) */ const HBUINT16 input[], /* Array of input values--start with second glyph */ unsigned int lookaheadCount, const HBUINT16 lookahead[], unsigned int lookupCount, const LookupRecord lookupRecord[], ChainContextApplyLookupContext &lookup_context) { unsigned end_index = c->buffer->idx; unsigned match_end = 0; unsigned match_positions[HB_MAX_CONTEXT_LENGTH]; if (!(match_input (c, inputCount, input, lookup_context.funcs.match, lookup_context.match_data[1], &match_end, match_positions) && (end_index = match_end) && match_lookahead (c, lookaheadCount, lookahead, lookup_context.funcs.match, lookup_context.match_data[2], match_end, &end_index))) { c->buffer->unsafe_to_concat (c->buffer->idx, end_index); return false; } unsigned start_index = c->buffer->out_len; if (!match_backtrack (c, backtrackCount, backtrack, lookup_context.funcs.match, lookup_context.match_data[0], &start_index)) { c->buffer->unsafe_to_concat_from_outbuffer (start_index, end_index); return false; } c->buffer->unsafe_to_break_from_outbuffer (start_index, end_index); apply_lookup (c, inputCount, match_positions, lookupCount, lookupRecord, match_end); return true; } struct ChainRule { bool intersects (const hb_set_t *glyphs, ChainContextClosureLookupContext &lookup_context) const { const HeadlessArrayOf &input = StructAfter> (backtrack); const Array16Of &lookahead = StructAfter> (input); return chain_context_intersects (glyphs, backtrack.len, backtrack.arrayZ, input.lenP1, input.arrayZ, lookahead.len, lookahead.arrayZ, lookup_context); } void closure (hb_closure_context_t *c, unsigned value, ChainContextClosureLookupContext &lookup_context) const { if (unlikely (c->lookup_limit_exceeded ())) return; const HeadlessArrayOf &input = StructAfter> (backtrack); const Array16Of &lookahead = StructAfter> (input); const Array16Of &lookup = StructAfter> (lookahead); chain_context_closure_lookup (c, backtrack.len, backtrack.arrayZ, input.lenP1, input.arrayZ, lookahead.len, lookahead.arrayZ, lookup.len, lookup.arrayZ, value, lookup_context); } void closure_lookups (hb_closure_lookups_context_t *c, ChainContextClosureLookupContext &lookup_context) const { if (unlikely (c->lookup_limit_exceeded ())) return; if (!intersects (c->glyphs, lookup_context)) return; const HeadlessArrayOf &input = StructAfter> (backtrack); const Array16Of &lookahead = StructAfter> (input); const Array16Of &lookup = StructAfter> (lookahead); recurse_lookups (c, lookup.len, lookup.arrayZ); } void collect_glyphs (hb_collect_glyphs_context_t *c, ChainContextCollectGlyphsLookupContext &lookup_context) const { const HeadlessArrayOf &input = StructAfter> (backtrack); const Array16Of &lookahead = StructAfter> (input); const Array16Of &lookup = StructAfter> (lookahead); chain_context_collect_glyphs_lookup (c, backtrack.len, backtrack.arrayZ, input.lenP1, input.arrayZ, lookahead.len, lookahead.arrayZ, lookup.len, lookup.arrayZ, lookup_context); } bool would_apply (hb_would_apply_context_t *c, ChainContextApplyLookupContext &lookup_context) const { const HeadlessArrayOf &input = StructAfter> (backtrack); const Array16Of &lookahead = StructAfter> (input); const Array16Of &lookup = StructAfter> (lookahead); return chain_context_would_apply_lookup (c, backtrack.len, backtrack.arrayZ, input.lenP1, input.arrayZ, lookahead.len, lookahead.arrayZ, lookup.len, lookup.arrayZ, lookup_context); } bool apply (hb_ot_apply_context_t *c, ChainContextApplyLookupContext &lookup_context) const { TRACE_APPLY (this); const HeadlessArrayOf &input = StructAfter> (backtrack); const Array16Of &lookahead = StructAfter> (input); const Array16Of &lookup = StructAfter> (lookahead); return_trace (chain_context_apply_lookup (c, backtrack.len, backtrack.arrayZ, input.lenP1, input.arrayZ, lookahead.len, lookahead.arrayZ, lookup.len, lookup.arrayZ, lookup_context)); } template void serialize_array (hb_serialize_context_t *c, HBUINT16 len, Iterator it) const { c->copy (len); for (const auto g : it) c->copy ((HBUINT16) g); } bool serialize (hb_serialize_context_t *c, const hb_map_t *lookup_map, const hb_map_t *backtrack_map, const hb_map_t *input_map = nullptr, const hb_map_t *lookahead_map = nullptr) const { TRACE_SERIALIZE (this); auto *out = c->start_embed (this); if (unlikely (!out)) return_trace (false); const hb_map_t *mapping = backtrack_map; serialize_array (c, backtrack.len, + backtrack.iter () | hb_map (mapping)); const HeadlessArrayOf &input = StructAfter> (backtrack); if (input_map) mapping = input_map; serialize_array (c, input.lenP1, + input.iter () | hb_map (mapping)); const Array16Of &lookahead = StructAfter> (input); if (lookahead_map) mapping = lookahead_map; serialize_array (c, lookahead.len, + lookahead.iter () | hb_map (mapping)); const Array16Of &lookupRecord = StructAfter> (lookahead); HBUINT16* lookupCount = c->embed (&(lookupRecord.len)); if (!lookupCount) return_trace (false); unsigned count = serialize_lookuprecord_array (c, lookupRecord.as_array (), lookup_map); return_trace (c->check_assign (*lookupCount, count, HB_SERIALIZE_ERROR_INT_OVERFLOW)); } bool subset (hb_subset_context_t *c, const hb_map_t *lookup_map, const hb_map_t *backtrack_map = nullptr, const hb_map_t *input_map = nullptr, const hb_map_t *lookahead_map = nullptr) const { TRACE_SUBSET (this); const HeadlessArrayOf &input = StructAfter> (backtrack); const Array16Of &lookahead = StructAfter> (input); if (!backtrack_map) { const hb_set_t &glyphset = *c->plan->glyphset_gsub (); if (!hb_all (backtrack, glyphset) || !hb_all (input, glyphset) || !hb_all (lookahead, glyphset)) return_trace (false); serialize (c->serializer, lookup_map, c->plan->glyph_map); } else { if (!hb_all (backtrack, backtrack_map) || !hb_all (input, input_map) || !hb_all (lookahead, lookahead_map)) return_trace (false); serialize (c->serializer, lookup_map, backtrack_map, input_map, lookahead_map); } return_trace (true); } bool sanitize (hb_sanitize_context_t *c) const { TRACE_SANITIZE (this); if (!backtrack.sanitize (c)) return_trace (false); const HeadlessArrayOf &input = StructAfter> (backtrack); if (!input.sanitize (c)) return_trace (false); const Array16Of &lookahead = StructAfter> (input); if (!lookahead.sanitize (c)) return_trace (false); const Array16Of &lookup = StructAfter> (lookahead); return_trace (lookup.sanitize (c)); } protected: Array16Of backtrack; /* Array of backtracking values * (to be matched before the input * sequence) */ HeadlessArrayOf inputX; /* Array of input values (start with * second glyph) */ Array16Of lookaheadX; /* Array of lookahead values's (to be * matched after the input sequence) */ Array16Of lookupX; /* Array of LookupRecords--in * design order) */ public: DEFINE_SIZE_MIN (8); }; struct ChainRuleSet { bool intersects (const hb_set_t *glyphs, ChainContextClosureLookupContext &lookup_context) const { return + hb_iter (rule) | hb_map (hb_add (this)) | hb_map ([&] (const ChainRule &_) { return _.intersects (glyphs, lookup_context); }) | hb_any ; } void closure (hb_closure_context_t *c, unsigned value, ChainContextClosureLookupContext &lookup_context) const { if (unlikely (c->lookup_limit_exceeded ())) return; return + hb_iter (rule) | hb_map (hb_add (this)) | hb_apply ([&] (const ChainRule &_) { _.closure (c, value, lookup_context); }) ; } void closure_lookups (hb_closure_lookups_context_t *c, ChainContextClosureLookupContext &lookup_context) const { if (unlikely (c->lookup_limit_exceeded ())) return; + hb_iter (rule) | hb_map (hb_add (this)) | hb_apply ([&] (const ChainRule &_) { _.closure_lookups (c, lookup_context); }) ; } void collect_glyphs (hb_collect_glyphs_context_t *c, ChainContextCollectGlyphsLookupContext &lookup_context) const { return + hb_iter (rule) | hb_map (hb_add (this)) | hb_apply ([&] (const ChainRule &_) { _.collect_glyphs (c, lookup_context); }) ; } bool would_apply (hb_would_apply_context_t *c, ChainContextApplyLookupContext &lookup_context) const { return + hb_iter (rule) | hb_map (hb_add (this)) | hb_map ([&] (const ChainRule &_) { return _.would_apply (c, lookup_context); }) | hb_any ; } bool apply (hb_ot_apply_context_t *c, ChainContextApplyLookupContext &lookup_context) const { TRACE_APPLY (this); return_trace ( + hb_iter (rule) | hb_map (hb_add (this)) | hb_map ([&] (const ChainRule &_) { return _.apply (c, lookup_context); }) | hb_any ) ; } bool subset (hb_subset_context_t *c, const hb_map_t *lookup_map, const hb_map_t *backtrack_klass_map = nullptr, const hb_map_t *input_klass_map = nullptr, const hb_map_t *lookahead_klass_map = nullptr) const { TRACE_SUBSET (this); auto snap = c->serializer->snapshot (); auto *out = c->serializer->start_embed (*this); if (unlikely (!c->serializer->extend_min (out))) return_trace (false); for (const Offset16To& _ : rule) { if (!_) continue; auto o_snap = c->serializer->snapshot (); auto *o = out->rule.serialize_append (c->serializer); if (unlikely (!o)) continue; if (!o->serialize_subset (c, _, this, lookup_map, backtrack_klass_map, input_klass_map, lookahead_klass_map)) { out->rule.pop (); c->serializer->revert (o_snap); } } bool ret = bool (out->rule); if (!ret) c->serializer->revert (snap); return_trace (ret); } bool sanitize (hb_sanitize_context_t *c) const { TRACE_SANITIZE (this); return_trace (rule.sanitize (c, this)); } protected: Array16OfOffset16To rule; /* Array of ChainRule tables * ordered by preference */ public: DEFINE_SIZE_ARRAY (2, rule); }; struct ChainContextFormat1 { bool intersects (const hb_set_t *glyphs) const { struct ChainContextClosureLookupContext lookup_context = { {intersects_glyph, intersected_glyph}, ContextFormat::SimpleContext, {nullptr, nullptr, nullptr} }; return + hb_zip (this+coverage, ruleSet) | hb_filter (*glyphs, hb_first) | hb_map (hb_second) | hb_map (hb_add (this)) | hb_map ([&] (const ChainRuleSet &_) { return _.intersects (glyphs, lookup_context); }) | hb_any ; } bool may_have_non_1to1 () const { return true; } void closure (hb_closure_context_t *c) const { hb_set_t* cur_active_glyphs = &c->push_cur_active_glyphs (); get_coverage ().intersected_coverage_glyphs (&c->previous_parent_active_glyphs (), cur_active_glyphs); struct ChainContextClosureLookupContext lookup_context = { {intersects_glyph, intersected_glyph}, ContextFormat::SimpleContext, {nullptr, nullptr, nullptr} }; + hb_zip (this+coverage, hb_range ((unsigned) ruleSet.len)) | hb_filter ([&] (hb_codepoint_t _) { return c->previous_parent_active_glyphs ().has (_); }, hb_first) | hb_map ([&](const hb_pair_t _) { return hb_pair_t (_.first, this+ruleSet[_.second]); }) | hb_apply ([&] (const hb_pair_t& _) { _.second.closure (c, _.first, lookup_context); }) ; c->pop_cur_done_glyphs (); } void closure_lookups (hb_closure_lookups_context_t *c) const { struct ChainContextClosureLookupContext lookup_context = { {intersects_glyph, intersected_glyph}, ContextFormat::SimpleContext, {nullptr, nullptr, nullptr} }; + hb_zip (this+coverage, ruleSet) | hb_filter (*c->glyphs, hb_first) | hb_map (hb_second) | hb_map (hb_add (this)) | hb_apply ([&] (const ChainRuleSet &_) { _.closure_lookups (c, lookup_context); }) ; } void collect_variation_indices (hb_collect_variation_indices_context_t *c) const {} void collect_glyphs (hb_collect_glyphs_context_t *c) const { (this+coverage).collect_coverage (c->input); struct ChainContextCollectGlyphsLookupContext lookup_context = { {collect_glyph}, {nullptr, nullptr, nullptr} }; + hb_iter (ruleSet) | hb_map (hb_add (this)) | hb_apply ([&] (const ChainRuleSet &_) { _.collect_glyphs (c, lookup_context); }) ; } bool would_apply (hb_would_apply_context_t *c) const { const ChainRuleSet &rule_set = this+ruleSet[(this+coverage).get_coverage (c->glyphs[0])]; struct ChainContextApplyLookupContext lookup_context = { {match_glyph}, {nullptr, nullptr, nullptr} }; return rule_set.would_apply (c, lookup_context); } const Coverage &get_coverage () const { return this+coverage; } bool apply (hb_ot_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); const ChainRuleSet &rule_set = this+ruleSet[index]; struct ChainContextApplyLookupContext lookup_context = { {match_glyph}, {nullptr, nullptr, nullptr} }; return_trace (rule_set.apply (c, lookup_context)); } bool subset (hb_subset_context_t *c) const { TRACE_SUBSET (this); const hb_set_t &glyphset = *c->plan->glyphset_gsub (); const hb_map_t &glyph_map = *c->plan->glyph_map; auto *out = c->serializer->start_embed (*this); if (unlikely (!c->serializer->extend_min (out))) return_trace (false); out->format = format; const hb_map_t *lookup_map = c->table_tag == HB_OT_TAG_GSUB ? c->plan->gsub_lookups : c->plan->gpos_lookups; hb_sorted_vector_t new_coverage; + hb_zip (this+coverage, ruleSet) | hb_filter (glyphset, hb_first) | hb_filter (subset_offset_array (c, out->ruleSet, this, lookup_map), hb_second) | hb_map (hb_first) | hb_map (glyph_map) | hb_sink (new_coverage) ; out->coverage.serialize_serialize (c->serializer, new_coverage.iter ()); return_trace (bool (new_coverage)); } bool sanitize (hb_sanitize_context_t *c) const { TRACE_SANITIZE (this); return_trace (coverage.sanitize (c, this) && ruleSet.sanitize (c, this)); } protected: HBUINT16 format; /* Format identifier--format = 1 */ Offset16To coverage; /* Offset to Coverage table--from * beginning of table */ Array16OfOffset16To ruleSet; /* Array of ChainRuleSet tables * ordered by Coverage Index */ public: DEFINE_SIZE_ARRAY (6, ruleSet); }; struct ChainContextFormat2 { bool intersects (const hb_set_t *glyphs) const { if (!(this+coverage).intersects (glyphs)) return false; const ClassDef &backtrack_class_def = this+backtrackClassDef; const ClassDef &input_class_def = this+inputClassDef; const ClassDef &lookahead_class_def = this+lookaheadClassDef; struct ChainContextClosureLookupContext lookup_context = { {intersects_class, intersected_class_glyphs}, ContextFormat::ClassBasedContext, {&backtrack_class_def, &input_class_def, &lookahead_class_def} }; hb_set_t retained_coverage_glyphs; (this+coverage).intersected_coverage_glyphs (glyphs, &retained_coverage_glyphs); hb_set_t coverage_glyph_classes; input_class_def.intersected_classes (&retained_coverage_glyphs, &coverage_glyph_classes); return + hb_iter (ruleSet) | hb_map (hb_add (this)) | hb_enumerate | hb_map ([&] (const hb_pair_t p) { return input_class_def.intersects_class (glyphs, p.first) && coverage_glyph_classes.has (p.first) && p.second.intersects (glyphs, lookup_context); }) | hb_any ; } bool may_have_non_1to1 () const { return true; } void closure (hb_closure_context_t *c) const { if (!(this+coverage).intersects (c->glyphs)) return; hb_set_t* cur_active_glyphs = &c->push_cur_active_glyphs (); get_coverage ().intersected_coverage_glyphs (&c->previous_parent_active_glyphs (), cur_active_glyphs); const ClassDef &backtrack_class_def = this+backtrackClassDef; const ClassDef &input_class_def = this+inputClassDef; const ClassDef &lookahead_class_def = this+lookaheadClassDef; struct ChainContextClosureLookupContext lookup_context = { {intersects_class, intersected_class_glyphs}, ContextFormat::ClassBasedContext, {&backtrack_class_def, &input_class_def, &lookahead_class_def} }; + hb_enumerate (ruleSet) | hb_filter ([&] (unsigned _) { return input_class_def.intersects_class (&c->parent_active_glyphs (), _); }, hb_first) | hb_apply ([&] (const hb_pair_t&> _) { const ChainRuleSet& chainrule_set = this+_.second; chainrule_set.closure (c, _.first, lookup_context); }) ; c->pop_cur_done_glyphs (); } void closure_lookups (hb_closure_lookups_context_t *c) const { if (!(this+coverage).intersects (c->glyphs)) return; const ClassDef &backtrack_class_def = this+backtrackClassDef; const ClassDef &input_class_def = this+inputClassDef; const ClassDef &lookahead_class_def = this+lookaheadClassDef; struct ChainContextClosureLookupContext lookup_context = { {intersects_class, intersected_class_glyphs}, ContextFormat::ClassBasedContext, {&backtrack_class_def, &input_class_def, &lookahead_class_def} }; + hb_iter (ruleSet) | hb_map (hb_add (this)) | hb_enumerate | hb_filter([&] (unsigned klass) { return input_class_def.intersects_class (c->glyphs, klass); }, hb_first) | hb_map (hb_second) | hb_apply ([&] (const ChainRuleSet &_) { _.closure_lookups (c, lookup_context); }) ; } void collect_variation_indices (hb_collect_variation_indices_context_t *c) const {} void collect_glyphs (hb_collect_glyphs_context_t *c) const { (this+coverage).collect_coverage (c->input); const ClassDef &backtrack_class_def = this+backtrackClassDef; const ClassDef &input_class_def = this+inputClassDef; const ClassDef &lookahead_class_def = this+lookaheadClassDef; struct ChainContextCollectGlyphsLookupContext lookup_context = { {collect_class}, {&backtrack_class_def, &input_class_def, &lookahead_class_def} }; + hb_iter (ruleSet) | hb_map (hb_add (this)) | hb_apply ([&] (const ChainRuleSet &_) { _.collect_glyphs (c, lookup_context); }) ; } bool would_apply (hb_would_apply_context_t *c) const { const ClassDef &backtrack_class_def = this+backtrackClassDef; const ClassDef &input_class_def = this+inputClassDef; const ClassDef &lookahead_class_def = this+lookaheadClassDef; unsigned int index = input_class_def.get_class (c->glyphs[0]); const ChainRuleSet &rule_set = this+ruleSet[index]; struct ChainContextApplyLookupContext lookup_context = { {match_class}, {&backtrack_class_def, &input_class_def, &lookahead_class_def} }; return rule_set.would_apply (c, lookup_context); } const Coverage &get_coverage () const { return this+coverage; } bool apply (hb_ot_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); const ClassDef &backtrack_class_def = this+backtrackClassDef; const ClassDef &input_class_def = this+inputClassDef; const ClassDef &lookahead_class_def = this+lookaheadClassDef; index = input_class_def.get_class (c->buffer->cur().codepoint); const ChainRuleSet &rule_set = this+ruleSet[index]; struct ChainContextApplyLookupContext lookup_context = { {match_class}, {&backtrack_class_def, &input_class_def, &lookahead_class_def} }; return_trace (rule_set.apply (c, lookup_context)); } bool subset (hb_subset_context_t *c) const { TRACE_SUBSET (this); auto *out = c->serializer->start_embed (*this); if (unlikely (!c->serializer->extend_min (out))) return_trace (false); out->format = format; out->coverage.serialize_subset (c, coverage, this); hb_map_t backtrack_klass_map; hb_map_t input_klass_map; hb_map_t lookahead_klass_map; out->backtrackClassDef.serialize_subset (c, backtrackClassDef, this, &backtrack_klass_map); // TODO: subset inputClassDef based on glyphs survived in Coverage subsetting out->inputClassDef.serialize_subset (c, inputClassDef, this, &input_klass_map); out->lookaheadClassDef.serialize_subset (c, lookaheadClassDef, this, &lookahead_klass_map); if (unlikely (!c->serializer->propagate_error (backtrack_klass_map, input_klass_map, lookahead_klass_map))) return_trace (false); const hb_set_t* glyphset = c->plan->glyphset_gsub (); hb_set_t retained_coverage_glyphs; (this+coverage).intersected_coverage_glyphs (glyphset, &retained_coverage_glyphs); hb_set_t coverage_glyph_classes; (this+inputClassDef).intersected_classes (&retained_coverage_glyphs, &coverage_glyph_classes); int non_zero_index = -1, index = 0; bool ret = true; const hb_map_t *lookup_map = c->table_tag == HB_OT_TAG_GSUB ? c->plan->gsub_lookups : c->plan->gpos_lookups; auto last_non_zero = c->serializer->snapshot (); for (const auto& _ : + hb_enumerate (ruleSet) | hb_filter (input_klass_map, hb_first)) { auto *o = out->ruleSet.serialize_append (c->serializer); if (unlikely (!o)) { ret = false; break; } if (coverage_glyph_classes.has (_.first) && o->serialize_subset (c, _.second, this, lookup_map, &backtrack_klass_map, &input_klass_map, &lookahead_klass_map)) { last_non_zero = c->serializer->snapshot (); non_zero_index = index; } index++; } if (!ret || non_zero_index == -1) return_trace (false); // prune empty trailing ruleSets if (index > non_zero_index) { c->serializer->revert (last_non_zero); out->ruleSet.len = non_zero_index + 1; } return_trace (bool (out->ruleSet)); } bool sanitize (hb_sanitize_context_t *c) const { TRACE_SANITIZE (this); return_trace (coverage.sanitize (c, this) && backtrackClassDef.sanitize (c, this) && inputClassDef.sanitize (c, this) && lookaheadClassDef.sanitize (c, this) && ruleSet.sanitize (c, this)); } protected: HBUINT16 format; /* Format identifier--format = 2 */ Offset16To coverage; /* Offset to Coverage table--from * beginning of table */ Offset16To backtrackClassDef; /* Offset to glyph ClassDef table * containing backtrack sequence * data--from beginning of table */ Offset16To inputClassDef; /* Offset to glyph ClassDef * table containing input sequence * data--from beginning of table */ Offset16To lookaheadClassDef; /* Offset to glyph ClassDef table * containing lookahead sequence * data--from beginning of table */ Array16OfOffset16To ruleSet; /* Array of ChainRuleSet tables * ordered by class */ public: DEFINE_SIZE_ARRAY (12, ruleSet); }; struct ChainContextFormat3 { bool intersects (const hb_set_t *glyphs) const { const Array16OfOffset16To &input = StructAfter> (backtrack); if (!(this+input[0]).intersects (glyphs)) return false; const Array16OfOffset16To &lookahead = StructAfter> (input); struct ChainContextClosureLookupContext lookup_context = { {intersects_coverage, intersected_coverage_glyphs}, ContextFormat::CoverageBasedContext, {this, this, this} }; return chain_context_intersects (glyphs, backtrack.len, (const HBUINT16 *) backtrack.arrayZ, input.len, (const HBUINT16 *) input.arrayZ + 1, lookahead.len, (const HBUINT16 *) lookahead.arrayZ, lookup_context); } bool may_have_non_1to1 () const { return true; } void closure (hb_closure_context_t *c) const { const Array16OfOffset16To &input = StructAfter> (backtrack); if (!(this+input[0]).intersects (c->glyphs)) return; hb_set_t* cur_active_glyphs = &c->push_cur_active_glyphs (); get_coverage ().intersected_coverage_glyphs (&c->previous_parent_active_glyphs (), cur_active_glyphs); const Array16OfOffset16To &lookahead = StructAfter> (input); const Array16Of &lookup = StructAfter> (lookahead); struct ChainContextClosureLookupContext lookup_context = { {intersects_coverage, intersected_coverage_glyphs}, ContextFormat::CoverageBasedContext, {this, this, this} }; chain_context_closure_lookup (c, backtrack.len, (const HBUINT16 *) backtrack.arrayZ, input.len, (const HBUINT16 *) input.arrayZ + 1, lookahead.len, (const HBUINT16 *) lookahead.arrayZ, lookup.len, lookup.arrayZ, 0, lookup_context); c->pop_cur_done_glyphs (); } void closure_lookups (hb_closure_lookups_context_t *c) const { if (!intersects (c->glyphs)) return; const Array16OfOffset16To &input = StructAfter> (backtrack); const Array16OfOffset16To &lookahead = StructAfter> (input); const Array16Of &lookup = StructAfter> (lookahead); recurse_lookups (c, lookup.len, lookup.arrayZ); } void collect_variation_indices (hb_collect_variation_indices_context_t *c) const {} void collect_glyphs (hb_collect_glyphs_context_t *c) const { const Array16OfOffset16To &input = StructAfter> (backtrack); (this+input[0]).collect_coverage (c->input); const Array16OfOffset16To &lookahead = StructAfter> (input); const Array16Of &lookup = StructAfter> (lookahead); struct ChainContextCollectGlyphsLookupContext lookup_context = { {collect_coverage}, {this, this, this} }; chain_context_collect_glyphs_lookup (c, backtrack.len, (const HBUINT16 *) backtrack.arrayZ, input.len, (const HBUINT16 *) input.arrayZ + 1, lookahead.len, (const HBUINT16 *) lookahead.arrayZ, lookup.len, lookup.arrayZ, lookup_context); } bool would_apply (hb_would_apply_context_t *c) const { const Array16OfOffset16To &input = StructAfter> (backtrack); const Array16OfOffset16To &lookahead = StructAfter> (input); const Array16Of &lookup = StructAfter> (lookahead); struct ChainContextApplyLookupContext lookup_context = { {match_coverage}, {this, this, this} }; return chain_context_would_apply_lookup (c, backtrack.len, (const HBUINT16 *) backtrack.arrayZ, input.len, (const HBUINT16 *) input.arrayZ + 1, lookahead.len, (const HBUINT16 *) lookahead.arrayZ, lookup.len, lookup.arrayZ, lookup_context); } const Coverage &get_coverage () const { const Array16OfOffset16To &input = StructAfter> (backtrack); return this+input[0]; } bool apply (hb_ot_apply_context_t *c) const { TRACE_APPLY (this); const Array16OfOffset16To &input = StructAfter> (backtrack); unsigned int index = (this+input[0]).get_coverage (c->buffer->cur().codepoint); if (likely (index == NOT_COVERED)) return_trace (false); const Array16OfOffset16To &lookahead = StructAfter> (input); const Array16Of &lookup = StructAfter> (lookahead); struct ChainContextApplyLookupContext lookup_context = { {match_coverage}, {this, this, this} }; return_trace (chain_context_apply_lookup (c, backtrack.len, (const HBUINT16 *) backtrack.arrayZ, input.len, (const HBUINT16 *) input.arrayZ + 1, lookahead.len, (const HBUINT16 *) lookahead.arrayZ, lookup.len, lookup.arrayZ, lookup_context)); } template bool serialize_coverage_offsets (hb_subset_context_t *c, Iterator it, const void* base) const { TRACE_SERIALIZE (this); auto *out = c->serializer->start_embed> (); if (unlikely (!c->serializer->allocate_size (HBUINT16::static_size))) return_trace (false); for (auto& offset : it) { auto *o = out->serialize_append (c->serializer); if (unlikely (!o) || !o->serialize_subset (c, offset, base)) return_trace (false); } return_trace (true); } bool subset (hb_subset_context_t *c) const { TRACE_SUBSET (this); auto *out = c->serializer->start_embed (this); if (unlikely (!out)) return_trace (false); if (unlikely (!c->serializer->embed (this->format))) return_trace (false); if (!serialize_coverage_offsets (c, backtrack.iter (), this)) return_trace (false); const Array16OfOffset16To &input = StructAfter> (backtrack); if (!serialize_coverage_offsets (c, input.iter (), this)) return_trace (false); const Array16OfOffset16To &lookahead = StructAfter> (input); if (!serialize_coverage_offsets (c, lookahead.iter (), this)) return_trace (false); const Array16Of &lookupRecord = StructAfter> (lookahead); const hb_map_t *lookup_map = c->table_tag == HB_OT_TAG_GSUB ? c->plan->gsub_lookups : c->plan->gpos_lookups; HBUINT16 *lookupCount = c->serializer->copy (lookupRecord.len); if (!lookupCount) return_trace (false); unsigned count = serialize_lookuprecord_array (c->serializer, lookupRecord.as_array (), lookup_map); return_trace (c->serializer->check_assign (*lookupCount, count, HB_SERIALIZE_ERROR_INT_OVERFLOW)); } bool sanitize (hb_sanitize_context_t *c) const { TRACE_SANITIZE (this); if (!backtrack.sanitize (c, this)) return_trace (false); const Array16OfOffset16To &input = StructAfter> (backtrack); if (!input.sanitize (c, this)) return_trace (false); if (!input.len) return_trace (false); /* To be consistent with Context. */ const Array16OfOffset16To &lookahead = StructAfter> (input); if (!lookahead.sanitize (c, this)) return_trace (false); const Array16Of &lookup = StructAfter> (lookahead); return_trace (lookup.sanitize (c)); } protected: HBUINT16 format; /* Format identifier--format = 3 */ Array16OfOffset16To backtrack; /* Array of coverage tables * in backtracking sequence, in glyph * sequence order */ Array16OfOffset16To inputX ; /* Array of coverage * tables in input sequence, in glyph * sequence order */ Array16OfOffset16To lookaheadX; /* Array of coverage tables * in lookahead sequence, in glyph * sequence order */ Array16Of lookupX; /* Array of LookupRecords--in * design order) */ public: DEFINE_SIZE_MIN (10); }; struct ChainContext { template typename context_t::return_t dispatch (context_t *c, Ts&&... ds) 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, std::forward (ds)...)); case 2: return_trace (c->dispatch (u.format2, std::forward (ds)...)); case 3: return_trace (c->dispatch (u.format3, std::forward (ds)...)); default:return_trace (c->default_return_value ()); } } protected: union { HBUINT16 format; /* Format identifier */ ChainContextFormat1 format1; ChainContextFormat2 format2; ChainContextFormat3 format3; } u; }; template struct ExtensionFormat1 { unsigned int get_type () const { return extensionLookupType; } template const X& get_subtable () const { return this + reinterpret_cast &> (extensionOffset); } template typename context_t::return_t dispatch (context_t *c, Ts&&... ds) const { TRACE_DISPATCH (this, format); if (unlikely (!c->may_dispatch (this, this))) return_trace (c->no_dispatch_return_value ()); return_trace (get_subtable ().dispatch (c, get_type (), std::forward (ds)...)); } void collect_variation_indices (hb_collect_variation_indices_context_t *c) const { dispatch (c); } /* This is called from may_dispatch() above with hb_sanitize_context_t. */ bool sanitize (hb_sanitize_context_t *c) const { TRACE_SANITIZE (this); return_trace (c->check_struct (this) && extensionLookupType != T::SubTable::Extension); } bool subset (hb_subset_context_t *c) const { TRACE_SUBSET (this); auto *out = c->serializer->start_embed (this); if (unlikely (!out || !c->serializer->extend_min (out))) return_trace (false); out->format = format; out->extensionLookupType = extensionLookupType; const auto& src_offset = reinterpret_cast &> (extensionOffset); auto& dest_offset = reinterpret_cast &> (out->extensionOffset); return_trace (dest_offset.serialize_subset (c, src_offset, this, get_type ())); } protected: HBUINT16 format; /* Format identifier. Set to 1. */ HBUINT16 extensionLookupType; /* Lookup type of subtable referenced * by ExtensionOffset (i.e. the * extension subtable). */ Offset32 extensionOffset; /* Offset to the extension subtable, * of lookup type subtable. */ public: DEFINE_SIZE_STATIC (8); }; template struct Extension { unsigned int get_type () const { switch (u.format) { case 1: return u.format1.get_type (); default:return 0; } } template const X& get_subtable () const { switch (u.format) { case 1: return u.format1.template get_subtable (); default:return Null (typename T::SubTable); } } // Specialization of dispatch for subset. dispatch() normally just // dispatches to the sub table this points too, but for subset // we need to run subset on this subtable too. template typename hb_subset_context_t::return_t dispatch (hb_subset_context_t *c, Ts&&... ds) const { switch (u.format) { case 1: return u.format1.subset (c); default: return c->default_return_value (); } } template typename context_t::return_t dispatch (context_t *c, Ts&&... ds) 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 (u.format1.dispatch (c, std::forward (ds)...)); default:return_trace (c->default_return_value ()); } } protected: union { HBUINT16 format; /* Format identifier */ ExtensionFormat1 format1; } u; }; /* * GSUB/GPOS Common */ struct hb_ot_layout_lookup_accelerator_t { template void init (const TLookup &lookup) { digest.init (); lookup.collect_coverage (&digest); subtables.init (); OT::hb_get_subtables_context_t c_get_subtables (subtables); lookup.dispatch (&c_get_subtables); } void fini () { subtables.fini (); } bool may_have (hb_codepoint_t g) const { return digest.may_have (g); } bool apply (hb_ot_apply_context_t *c) const { for (unsigned int i = 0; i < subtables.length; i++) if (subtables[i].apply (c)) return true; return false; } private: hb_set_digest_t digest; hb_get_subtables_context_t::array_t subtables; }; struct GSUBGPOS { bool has_data () const { return version.to_int (); } unsigned int get_script_count () const { return (this+scriptList).len; } const Tag& get_script_tag (unsigned int i) const { return (this+scriptList).get_tag (i); } unsigned int get_script_tags (unsigned int start_offset, unsigned int *script_count /* IN/OUT */, hb_tag_t *script_tags /* OUT */) const { return (this+scriptList).get_tags (start_offset, script_count, script_tags); } const Script& get_script (unsigned int i) const { return (this+scriptList)[i]; } bool find_script_index (hb_tag_t tag, unsigned int *index) const { return (this+scriptList).find_index (tag, index); } unsigned int get_feature_count () const { return (this+featureList).len; } hb_tag_t get_feature_tag (unsigned int i) const { return i == Index::NOT_FOUND_INDEX ? HB_TAG_NONE : (this+featureList).get_tag (i); } unsigned int get_feature_tags (unsigned int start_offset, unsigned int *feature_count /* IN/OUT */, hb_tag_t *feature_tags /* OUT */) const { return (this+featureList).get_tags (start_offset, feature_count, feature_tags); } const Feature& get_feature (unsigned int i) const { return (this+featureList)[i]; } bool find_feature_index (hb_tag_t tag, unsigned int *index) const { return (this+featureList).find_index (tag, index); } unsigned int get_lookup_count () const { return (this+lookupList).len; } const Lookup& get_lookup (unsigned int i) const { return (this+lookupList)[i]; } bool find_variations_index (const int *coords, unsigned int num_coords, unsigned int *index) const { #ifdef HB_NO_VAR *index = FeatureVariations::NOT_FOUND_INDEX; return false; #endif return (version.to_int () >= 0x00010001u ? this+featureVars : Null (FeatureVariations)) .find_index (coords, num_coords, index); } const Feature& get_feature_variation (unsigned int feature_index, unsigned int variations_index) const { #ifndef HB_NO_VAR if (FeatureVariations::NOT_FOUND_INDEX != variations_index && version.to_int () >= 0x00010001u) { const Feature *feature = (this+featureVars).find_substitute (variations_index, feature_index); if (feature) return *feature; } #endif return get_feature (feature_index); } void feature_variation_collect_lookups (const hb_set_t *feature_indexes, hb_set_t *lookup_indexes /* OUT */) const { #ifndef HB_NO_VAR if (version.to_int () >= 0x00010001u) (this+featureVars).collect_lookups (feature_indexes, lookup_indexes); #endif } template void closure_lookups (hb_face_t *face, const hb_set_t *glyphs, hb_set_t *lookup_indexes /* IN/OUT */) const { hb_set_t visited_lookups, inactive_lookups; OT::hb_closure_lookups_context_t c (face, glyphs, &visited_lookups, &inactive_lookups); for (unsigned lookup_index : + hb_iter (lookup_indexes)) reinterpret_cast (get_lookup (lookup_index)).closure_lookups (&c, lookup_index); hb_set_union (lookup_indexes, &visited_lookups); hb_set_subtract (lookup_indexes, &inactive_lookups); } void prune_langsys (const hb_map_t *duplicate_feature_map, hb_hashmap_t *script_langsys_map, hb_set_t *new_feature_indexes /* OUT */) const { hb_prune_langsys_context_t c (this, script_langsys_map, duplicate_feature_map, new_feature_indexes); unsigned count = get_script_count (); for (unsigned script_index = 0; script_index < count; script_index++) { const Script& s = get_script (script_index); s.prune_langsys (&c, script_index); } } template bool subset (hb_subset_layout_context_t *c) const { TRACE_SUBSET (this); auto *out = c->subset_context->serializer->embed (*this); if (unlikely (!out)) return_trace (false); typedef LookupOffsetList TLookupList; reinterpret_cast &> (out->lookupList) .serialize_subset (c->subset_context, reinterpret_cast &> (lookupList), this, c); reinterpret_cast &> (out->featureList) .serialize_subset (c->subset_context, reinterpret_cast &> (featureList), this, c); out->scriptList.serialize_subset (c->subset_context, scriptList, this, c); #ifndef HB_NO_VAR if (version.to_int () >= 0x00010001u) { bool ret = out->featureVars.serialize_subset (c->subset_context, featureVars, this, c); if (!ret) { out->version.major = 1; out->version.minor = 0; } } #endif return_trace (true); } void find_duplicate_features (const hb_map_t *lookup_indices, const hb_set_t *feature_indices, hb_map_t *duplicate_feature_map /* OUT */) const { if (feature_indices->is_empty ()) return; hb_hashmap_t unique_features; //find out duplicate features after subset for (unsigned i : feature_indices->iter ()) { hb_tag_t t = get_feature_tag (i); if (t == HB_MAP_VALUE_INVALID) continue; if (!unique_features.has (t)) { hb_set_t* indices = hb_set_create (); if (unlikely (indices == hb_set_get_empty () || !unique_features.set (t, indices))) { hb_set_destroy (indices); for (auto _ : unique_features.iter ()) hb_set_destroy (_.second); return; } if (unique_features.get (t)) unique_features.get (t)->add (i); duplicate_feature_map->set (i, i); continue; } bool found = false; hb_set_t* same_tag_features = unique_features.get (t); for (unsigned other_f_index : same_tag_features->iter ()) { const Feature& f = get_feature (i); const Feature& other_f = get_feature (other_f_index); auto f_iter = + hb_iter (f.lookupIndex) | hb_filter (lookup_indices) ; auto other_f_iter = + hb_iter (other_f.lookupIndex) | hb_filter (lookup_indices) ; bool is_equal = true; for (; f_iter && other_f_iter; f_iter++, other_f_iter++) { unsigned a = *f_iter; unsigned b = *other_f_iter; if (a != b) { is_equal = false; break; } } if (is_equal == false || f_iter || other_f_iter) continue; found = true; duplicate_feature_map->set (i, other_f_index); break; } if (found == false) { same_tag_features->add (i); duplicate_feature_map->set (i, i); } } for (auto _ : unique_features.iter ()) hb_set_destroy (_.second); } void prune_features (const hb_map_t *lookup_indices, /* IN */ hb_set_t *feature_indices /* IN/OUT */) const { #ifndef HB_NO_VAR // This is the set of feature indices which have alternate versions defined // if the FeatureVariation's table and the alternate version(s) intersect the // set of lookup indices. hb_set_t alternate_feature_indices; if (version.to_int () >= 0x00010001u) (this+featureVars).closure_features (lookup_indices, &alternate_feature_indices); if (unlikely (alternate_feature_indices.in_error())) { feature_indices->err (); return; } #endif for (unsigned i : feature_indices->iter()) { const Feature& f = get_feature (i); hb_tag_t tag = get_feature_tag (i); if (tag == HB_TAG ('p', 'r', 'e', 'f')) // Note: Never ever drop feature 'pref', even if it's empty. // HarfBuzz chooses shaper for Khmer based on presence of this // feature. See thread at: // http://lists.freedesktop.org/archives/harfbuzz/2012-November/002660.html continue; if (!f.featureParams.is_null () && tag == HB_TAG ('s', 'i', 'z', 'e')) continue; if (!f.intersects_lookup_indexes (lookup_indices) #ifndef HB_NO_VAR && !alternate_feature_indices.has (i) #endif ) feature_indices->del (i); } } unsigned int get_size () const { return min_size + (version.to_int () >= 0x00010001u ? featureVars.static_size : 0); } template bool sanitize (hb_sanitize_context_t *c) const { TRACE_SANITIZE (this); typedef List16OfOffset16To TLookupList; if (unlikely (!(version.sanitize (c) && likely (version.major == 1) && scriptList.sanitize (c, this) && featureList.sanitize (c, this) && reinterpret_cast &> (lookupList).sanitize (c, this)))) return_trace (false); #ifndef HB_NO_VAR if (unlikely (!(version.to_int () < 0x00010001u || featureVars.sanitize (c, this)))) return_trace (false); #endif return_trace (true); } template struct accelerator_t { accelerator_t (hb_face_t *face) { this->table = hb_sanitize_context_t ().reference_table (face); if (unlikely (this->table->is_blocklisted (this->table.get_blob (), face))) { hb_blob_destroy (this->table.get_blob ()); this->table = hb_blob_get_empty (); } this->lookup_count = table->get_lookup_count (); this->accels = (hb_ot_layout_lookup_accelerator_t *) hb_calloc (this->lookup_count, sizeof (hb_ot_layout_lookup_accelerator_t)); if (unlikely (!this->accels)) { this->lookup_count = 0; this->table.destroy (); this->table = hb_blob_get_empty (); } for (unsigned int i = 0; i < this->lookup_count; i++) this->accels[i].init (table->get_lookup (i)); } ~accelerator_t () { for (unsigned int i = 0; i < this->lookup_count; i++) this->accels[i].fini (); hb_free (this->accels); this->table.destroy (); } hb_blob_ptr_t table; unsigned int lookup_count; hb_ot_layout_lookup_accelerator_t *accels; }; protected: FixedVersion<>version; /* Version of the GSUB/GPOS table--initially set * to 0x00010000u */ Offset16To scriptList; /* ScriptList table */ Offset16To featureList; /* FeatureList table */ Offset16To lookupList; /* LookupList table */ Offset32To featureVars; /* Offset to Feature Variations table--from beginning of table * (may be NULL). Introduced * in version 0x00010001. */ public: DEFINE_SIZE_MIN (10); }; } /* namespace OT */ #endif /* HB_OT_LAYOUT_GSUBGPOS_HH */