--- /dev/null 2019-02-21 13:14:21.200397537 -0800 +++ new/src/java.desktop/share/native/libfontmanager/harfbuzz/hb-subset-glyf.cc 2019-02-28 12:04:49.950502120 -0800 @@ -0,0 +1,310 @@ +/* + * 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, Roderick Sheeter + */ + +#include "hb-open-type.hh" +#include "hb-ot-glyf-table.hh" +#include "hb-set.h" +#include "hb-subset-glyf.hh" + +static bool +_calculate_glyf_and_loca_prime_size (const OT::glyf::accelerator_t &glyf, + hb_vector_t &glyph_ids, + hb_bool_t drop_hints, + bool *use_short_loca /* OUT */, + unsigned int *glyf_size /* OUT */, + unsigned int *loca_size /* OUT */, + hb_vector_t *instruction_ranges /* OUT */) +{ + unsigned int total = 0; + for (unsigned int i = 0; i < glyph_ids.length; i++) + { + hb_codepoint_t next_glyph = glyph_ids[i]; + if (!instruction_ranges->resize (instruction_ranges->length + 2)) + { + DEBUG_MSG(SUBSET, nullptr, "Failed to resize instruction_ranges."); + return false; + } + unsigned int *instruction_start = &(*instruction_ranges)[instruction_ranges->length - 2]; + *instruction_start = 0; + unsigned int *instruction_end = &(*instruction_ranges)[instruction_ranges->length - 1]; + *instruction_end = 0; + + unsigned int start_offset, end_offset; + if (unlikely (!(glyf.get_offsets (next_glyph, &start_offset, &end_offset) && + glyf.remove_padding (start_offset, &end_offset)))) + { + DEBUG_MSG(SUBSET, nullptr, "Invalid gid %d", next_glyph); + continue; + } + if (end_offset - start_offset < OT::glyf::GlyphHeader::static_size) + continue; /* 0-length glyph */ + + if (drop_hints) + { + if (unlikely (!glyf.get_instruction_offsets (start_offset, end_offset, + instruction_start, instruction_end))) + { + DEBUG_MSG(SUBSET, nullptr, "Unable to get instruction offsets for %d", next_glyph); + return false; + } + } + + total += end_offset - start_offset - (*instruction_end - *instruction_start); + /* round2 so short loca will work */ + total += total % 2; + } + + *glyf_size = total; + *use_short_loca = (total <= 131070); + *loca_size = (glyph_ids.length + 1) + * (*use_short_loca ? sizeof (OT::HBUINT16) : sizeof (OT::HBUINT32)); + + DEBUG_MSG(SUBSET, nullptr, "preparing to subset glyf: final size %d, loca size %d, using %s loca", + total, + *loca_size, + *use_short_loca ? "short" : "long"); + return true; +} + +static bool +_write_loca_entry (unsigned int id, + unsigned int offset, + bool is_short, + void *loca_prime, + unsigned int loca_size) +{ + unsigned int entry_size = is_short ? sizeof (OT::HBUINT16) : sizeof (OT::HBUINT32); + if ((id + 1) * entry_size <= loca_size) + { + if (is_short) { + ((OT::HBUINT16*) loca_prime) [id].set (offset / 2); + } else { + ((OT::HBUINT32*) loca_prime) [id].set (offset); + } + return true; + } + + // Offset was not written because the write is out of bounds. + DEBUG_MSG(SUBSET, + nullptr, + "WARNING: Attempted to write an out of bounds loca entry at index %d. Loca size is %d.", + id, + loca_size); + return false; +} + +static void +_update_components (hb_subset_plan_t * plan, + char * glyph_start, + unsigned int length) +{ + OT::glyf::CompositeGlyphHeader::Iterator iterator; + if (OT::glyf::CompositeGlyphHeader::get_iterator (glyph_start, + length, + &iterator)) + { + do + { + hb_codepoint_t new_gid; + if (!plan->new_gid_for_old_gid (iterator.current->glyphIndex, + &new_gid)) + continue; + + ((OT::glyf::CompositeGlyphHeader *) iterator.current)->glyphIndex.set (new_gid); + } while (iterator.move_to_next ()); + } +} + +static bool _remove_composite_instruction_flag (char *glyf_prime, unsigned int length) +{ + /* remove WE_HAVE_INSTRUCTIONS from flags in dest */ + OT::glyf::CompositeGlyphHeader::Iterator composite_it; + if (unlikely (!OT::glyf::CompositeGlyphHeader::get_iterator (glyf_prime, length, &composite_it))) return false; + const OT::glyf::CompositeGlyphHeader *glyph; + do { + glyph = composite_it.current; + OT::HBUINT16 *flags = const_cast (&glyph->flags); + flags->set ( (uint16_t) *flags & ~OT::glyf::CompositeGlyphHeader::WE_HAVE_INSTRUCTIONS); + } while (composite_it.move_to_next ()); + return true; +} + +static bool +_write_glyf_and_loca_prime (hb_subset_plan_t *plan, + const OT::glyf::accelerator_t &glyf, + const char *glyf_data, + bool use_short_loca, + hb_vector_t &instruction_ranges, + unsigned int glyf_prime_size, + char *glyf_prime_data /* OUT */, + unsigned int loca_prime_size, + char *loca_prime_data /* OUT */) +{ + hb_vector_t &glyph_ids = plan->glyphs; + char *glyf_prime_data_next = glyf_prime_data; + + bool success = true; + for (unsigned int i = 0; i < glyph_ids.length; i++) + { + unsigned int start_offset, end_offset; + if (unlikely (!(glyf.get_offsets (glyph_ids[i], &start_offset, &end_offset) && + glyf.remove_padding (start_offset, &end_offset)))) + end_offset = start_offset = 0; + + unsigned int instruction_start = instruction_ranges[i * 2]; + unsigned int instruction_end = instruction_ranges[i * 2 + 1]; + + int length = end_offset - start_offset - (instruction_end - instruction_start); + + if (glyf_prime_data_next + length > glyf_prime_data + glyf_prime_size) + { + DEBUG_MSG(SUBSET, + nullptr, + "WARNING: Attempted to write an out of bounds glyph entry for gid %d (length %d)", + i, length); + return false; + } + + if (instruction_start == instruction_end) + memcpy (glyf_prime_data_next, glyf_data + start_offset, length); + else + { + memcpy (glyf_prime_data_next, glyf_data + start_offset, instruction_start - start_offset); + memcpy (glyf_prime_data_next + instruction_start - start_offset, glyf_data + instruction_end, end_offset - instruction_end); + /* if the instructions end at the end this was a composite glyph, else simple */ + if (instruction_end == end_offset) + { + if (unlikely (!_remove_composite_instruction_flag (glyf_prime_data_next, length))) return false; + } + else + /* zero instruction length, which is just before instruction_start */ + memset (glyf_prime_data_next + instruction_start - start_offset - 2, 0, 2); + } + + success = success && _write_loca_entry (i, + glyf_prime_data_next - glyf_prime_data, + use_short_loca, + loca_prime_data, + loca_prime_size); + _update_components (plan, glyf_prime_data_next, length); + + // TODO: don't align to two bytes if using long loca. + glyf_prime_data_next += length + (length % 2); // Align to 2 bytes for short loca. + } + + success = success && _write_loca_entry (glyph_ids.length, + glyf_prime_data_next - glyf_prime_data, + use_short_loca, + loca_prime_data, + loca_prime_size); + return success; +} + +static bool +_hb_subset_glyf_and_loca (const OT::glyf::accelerator_t &glyf, + const char *glyf_data, + hb_subset_plan_t *plan, + bool *use_short_loca, + hb_blob_t **glyf_prime /* OUT */, + hb_blob_t **loca_prime /* OUT */) +{ + // TODO(grieger): Sanity check allocation size for the new table. + hb_vector_t &glyphs_to_retain = plan->glyphs; + + unsigned int glyf_prime_size; + unsigned int loca_prime_size; + hb_vector_t instruction_ranges; + instruction_ranges.init (); + + if (unlikely (!_calculate_glyf_and_loca_prime_size (glyf, + glyphs_to_retain, + plan->drop_hints, + use_short_loca, + &glyf_prime_size, + &loca_prime_size, + &instruction_ranges))) { + instruction_ranges.fini (); + return false; + } + + char *glyf_prime_data = (char *) calloc (1, glyf_prime_size); + char *loca_prime_data = (char *) calloc (1, loca_prime_size); + if (unlikely (!_write_glyf_and_loca_prime (plan, glyf, glyf_data, + *use_short_loca, + instruction_ranges, + glyf_prime_size, glyf_prime_data, + loca_prime_size, loca_prime_data))) { + free (glyf_prime_data); + free (loca_prime_data); + instruction_ranges.fini (); + return false; + } + instruction_ranges.fini (); + + *glyf_prime = hb_blob_create (glyf_prime_data, + glyf_prime_size, + HB_MEMORY_MODE_READONLY, + glyf_prime_data, + free); + *loca_prime = hb_blob_create (loca_prime_data, + loca_prime_size, + HB_MEMORY_MODE_READONLY, + loca_prime_data, + free); + return true; +} + +/** + * hb_subset_glyf: + * Subsets the glyph table according to a provided plan. + * + * Return value: subsetted glyf table. + * + * Since: 1.7.5 + **/ +bool +hb_subset_glyf_and_loca (hb_subset_plan_t *plan, + bool *use_short_loca, /* OUT */ + hb_blob_t **glyf_prime, /* OUT */ + hb_blob_t **loca_prime /* OUT */) +{ + hb_blob_t *glyf_blob = hb_sanitize_context_t ().reference_table (plan->source); + const char *glyf_data = hb_blob_get_data (glyf_blob, nullptr); + + OT::glyf::accelerator_t glyf; + glyf.init (plan->source); + bool result = _hb_subset_glyf_and_loca (glyf, + glyf_data, + plan, + use_short_loca, + glyf_prime, + loca_prime); + + hb_blob_destroy (glyf_blob); + glyf.fini (); + + return result; +}