/* * Copyright © 2018 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. * * Google Author(s): Garret Rieger, Rod Sheeter, Behdad Esfahbod */ #include "hb-private.hh" #include "hb-object-private.hh" #include "hb-open-type-private.hh" #include "hb-subset-glyf.hh" #include "hb-subset-private.hh" #include "hb-subset-plan.hh" #include "hb-open-file-private.hh" #include "hb-ot-cmap-table.hh" #include "hb-ot-glyf-table.hh" #include "hb-ot-hdmx-table.hh" #include "hb-ot-head-table.hh" #include "hb-ot-hhea-table.hh" #include "hb-ot-hmtx-table.hh" #include "hb-ot-maxp-table.hh" #include "hb-ot-os2-table.hh" #include "hb-ot-post-table.hh" struct hb_subset_profile_t { hb_object_header_t header; ASSERT_POD (); }; /** * hb_subset_profile_create: * * Return value: New profile with default settings. * * Since: 1.8.0 **/ hb_subset_profile_t * hb_subset_profile_create () { return hb_object_create(); } /** * hb_subset_profile_destroy: * * Since: 1.8.0 **/ void hb_subset_profile_destroy (hb_subset_profile_t *profile) { if (!hb_object_destroy (profile)) return; free (profile); } template static bool _subset (hb_subset_plan_t *plan) { OT::Sanitizer sanitizer; hb_blob_t *source_blob = sanitizer.sanitize (plan->source->reference_table (TableType::tableTag)); const TableType *table = source_blob->as (); hb_tag_t tag = TableType::tableTag; hb_bool_t result = false; if (table != &Null(TableType)) { result = table->subset(plan); } else { DEBUG_MSG(SUBSET, nullptr, "OT::%c%c%c%c::subset sanitize failed on source table.", HB_UNTAG(tag)); } hb_blob_destroy (source_blob); DEBUG_MSG(SUBSET, nullptr, "OT::%c%c%c%c::subset %s", HB_UNTAG(tag), result ? "success" : "FAILED!"); return result; } /* * A face that has add_table(). */ struct hb_subset_face_data_t { struct table_entry_t { inline int cmp (const hb_tag_t *t) const { if (*t < tag) return -1; if (*t > tag) return -1; return 0; } hb_tag_t tag; hb_blob_t *blob; }; hb_vector_t tables; }; static hb_subset_face_data_t * _hb_subset_face_data_create (void) { hb_subset_face_data_t *data = (hb_subset_face_data_t *) calloc (1, sizeof (hb_subset_face_data_t)); if (unlikely (!data)) return nullptr; data->tables.init (); return data; } static void _hb_subset_face_data_destroy (void *user_data) { hb_subset_face_data_t *data = (hb_subset_face_data_t *) user_data; for (unsigned int i = 0; i < data->tables.len; i++) hb_blob_destroy (data->tables[i].blob); data->tables.fini (); free (data); } static hb_blob_t * _hb_subset_face_data_reference_blob (hb_subset_face_data_t *data) { unsigned int table_count = data->tables.len; unsigned int face_length = table_count * 16 + 12; for (unsigned int i = 0; i < table_count; i++) face_length += _hb_ceil_to_4 (hb_blob_get_length (data->tables.arrayZ[i].blob)); char *buf = (char *) malloc (face_length); if (unlikely (!buf)) return nullptr; OT::hb_serialize_context_t c (buf, face_length); OT::OpenTypeFontFile *f = c.start_serialize (); bool is_cff = data->tables.lsearch (HB_TAG ('C','F','F',' ')) || data->tables.lsearch (HB_TAG ('C','F','F','2')); hb_tag_t sfnt_tag = is_cff ? OT::OpenTypeFontFile::CFFTag : OT::OpenTypeFontFile::TrueTypeTag; OT::Supplier tags_supplier (&data->tables[0].tag, table_count, sizeof (data->tables[0])); OT::Supplier blobs_supplier (&data->tables[0].blob, table_count, sizeof (data->tables[0])); bool ret = f->serialize_single (&c, sfnt_tag, tags_supplier, blobs_supplier, table_count); c.end_serialize (); if (unlikely (!ret)) { free (buf); return nullptr; } return hb_blob_create (buf, face_length, HB_MEMORY_MODE_WRITABLE, buf, free); } static hb_blob_t * _hb_subset_face_reference_table (hb_face_t *face, hb_tag_t tag, void *user_data) { hb_subset_face_data_t *data = (hb_subset_face_data_t *) user_data; if (!tag) return _hb_subset_face_data_reference_blob (data); hb_subset_face_data_t::table_entry_t *entry = data->tables.lsearch (tag); if (entry) return hb_blob_reference (entry->blob); return nullptr; } /* TODO: Move this to hb-face.h and rename to hb_face_builder_create() * with hb_face_builder_add_table(). */ hb_face_t * hb_subset_face_create (void) { hb_subset_face_data_t *data = _hb_subset_face_data_create (); if (unlikely (!data)) return hb_face_get_empty (); return hb_face_create_for_tables (_hb_subset_face_reference_table, data, _hb_subset_face_data_destroy); } hb_bool_t hb_subset_face_add_table (hb_face_t *face, hb_tag_t tag, hb_blob_t *blob) { if (unlikely (face->destroy != (hb_destroy_func_t) _hb_subset_face_data_destroy)) return false; hb_subset_face_data_t *data = (hb_subset_face_data_t *) face->user_data; hb_subset_face_data_t::table_entry_t *entry = data->tables.push (); entry->tag = tag; entry->blob = hb_blob_reference (blob); return true; } static bool _subset_table (hb_subset_plan_t *plan, hb_tag_t tag) { DEBUG_MSG(SUBSET, nullptr, "begin subset %c%c%c%c", HB_UNTAG(tag)); bool result = true; switch (tag) { case HB_OT_TAG_glyf: result = _subset (plan); break; case HB_OT_TAG_hdmx: result = _subset (plan); break; case HB_OT_TAG_head: // TODO that won't work well if there is no glyf DEBUG_MSG(SUBSET, nullptr, "skip head, handled by glyf"); result = true; break; case HB_OT_TAG_hhea: DEBUG_MSG(SUBSET, nullptr, "skip hhea handled by hmtx"); return true; case HB_OT_TAG_hmtx: result = _subset (plan); break; case HB_OT_TAG_vhea: DEBUG_MSG(SUBSET, nullptr, "skip vhea handled by vmtx"); return true; case HB_OT_TAG_vmtx: result = _subset (plan); break; case HB_OT_TAG_maxp: result = _subset (plan); break; case HB_OT_TAG_loca: DEBUG_MSG(SUBSET, nullptr, "skip loca handled by glyf"); return true; case HB_OT_TAG_cmap: result = _subset (plan); break; case HB_OT_TAG_os2: result = _subset (plan); break; case HB_OT_TAG_post: result = _subset (plan); break; default: hb_blob_t *source_table = hb_face_reference_table(plan->source, tag); if (likely (source_table)) result = plan->add_table(tag, source_table); else result = false; hb_blob_destroy (source_table); break; } DEBUG_MSG(SUBSET, nullptr, "subset %c%c%c%c %s", HB_UNTAG(tag), result ? "ok" : "FAILED"); return result; } static bool _should_drop_table(hb_subset_plan_t *plan, hb_tag_t tag) { switch (tag) { case HB_TAG ('c', 'v', 'a', 'r'): /* hint table, fallthrough */ case HB_TAG ('c', 'v', 't', ' '): /* hint table, fallthrough */ case HB_TAG ('f', 'p', 'g', 'm'): /* hint table, fallthrough */ case HB_TAG ('p', 'r', 'e', 'p'): /* hint table, fallthrough */ case HB_TAG ('h', 'd', 'm', 'x'): /* hint table, fallthrough */ case HB_TAG ('V', 'D', 'M', 'X'): /* hint table, fallthrough */ return plan->drop_hints; // Drop Layout Tables if requested. case HB_TAG ('G', 'D', 'E', 'F'): /* temporary */ case HB_TAG ('G', 'P', 'O', 'S'): /* temporary */ case HB_TAG ('G', 'S', 'U', 'B'): /* temporary */ return plan->drop_ot_layout; // Drop these tables below by default, list pulled // from fontTools: case HB_TAG ('B', 'A', 'S', 'E'): case HB_TAG ('J', 'S', 'T', 'F'): case HB_TAG ('D', 'S', 'I', 'G'): case HB_TAG ('E', 'B', 'D', 'T'): case HB_TAG ('E', 'B', 'L', 'C'): case HB_TAG ('E', 'B', 'S', 'C'): case HB_TAG ('S', 'V', 'G', ' '): case HB_TAG ('P', 'C', 'L', 'T'): case HB_TAG ('L', 'T', 'S', 'H'): // Graphite tables: case HB_TAG ('F', 'e', 'a', 't'): case HB_TAG ('G', 'l', 'a', 't'): case HB_TAG ('G', 'l', 'o', 'c'): case HB_TAG ('S', 'i', 'l', 'f'): case HB_TAG ('S', 'i', 'l', 'l'): // Colour case HB_TAG ('s', 'b', 'i', 'x'): return true; default: return false; } } /** * hb_subset: * @source: font face data to be subset. * @profile: profile to use for the subsetting. * @input: input to use for the subsetting. * * Subsets a font according to provided profile and input. **/ hb_face_t * hb_subset (hb_face_t *source, hb_subset_profile_t *profile, hb_subset_input_t *input) { if (unlikely (!profile || !input || !source)) return hb_face_get_empty(); hb_subset_plan_t *plan = hb_subset_plan_create (source, profile, input); hb_tag_t table_tags[32]; unsigned int offset = 0, count; bool success = true; do { count = ARRAY_LENGTH (table_tags); hb_face_get_table_tags (source, offset, &count, table_tags); for (unsigned int i = 0; i < count; i++) { hb_tag_t tag = table_tags[i]; if (_should_drop_table(plan, tag)) { DEBUG_MSG(SUBSET, nullptr, "drop %c%c%c%c", HB_UNTAG(tag)); continue; } success = success && _subset_table (plan, tag); } offset += count; } while (count == ARRAY_LENGTH (table_tags)); hb_face_t *result = success ? hb_face_reference(plan->dest) : hb_face_get_empty(); hb_subset_plan_destroy (plan); return result; } /** * hb_subset_get_all_codepoints: * @source: font face data to load. * @out: set to add the all codepoints covered by font face, source. */ void hb_subset_get_all_codepoints (hb_face_t *source, hb_set_t *out) { OT::cmap::accelerator_t cmap; cmap.init (source); cmap.get_all_codepoints (out); cmap.fini(); }