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Diffstat (limited to 'Build/source/libs/harfbuzz/harfbuzz-src/src/hb-subset.cc')
-rw-r--r-- | Build/source/libs/harfbuzz/harfbuzz-src/src/hb-subset.cc | 339 |
1 files changed, 339 insertions, 0 deletions
diff --git a/Build/source/libs/harfbuzz/harfbuzz-src/src/hb-subset.cc b/Build/source/libs/harfbuzz/harfbuzz-src/src/hb-subset.cc new file mode 100644 index 00000000000..9ebe5d31da2 --- /dev/null +++ b/Build/source/libs/harfbuzz/harfbuzz-src/src/hb-subset.cc @@ -0,0 +1,339 @@ +/* + * 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" + + +#ifndef HB_NO_VISIBILITY +const void * const OT::_hb_NullPool[HB_NULL_POOL_SIZE / sizeof (void *)] = {}; +#endif + + +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_t>(); +} + +/** + * 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<typename TableType> +static bool +_subset (hb_subset_plan_t *plan) +{ + OT::Sanitizer<TableType> sanitizer; + + hb_blob_t *source_blob = sanitizer.sanitize (plan->source->reference_table (TableType::tableTag)); + const TableType *table = OT::Sanitizer<TableType>::lock_instance (source_blob); + + hb_bool_t result = false; + if (table != &OT::Null(TableType)) + result = table->subset(plan); + + hb_blob_destroy (source_blob); + hb_tag_t tag = TableType::tableTag; + 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_prealloced_array_t<table_entry_t, 32> 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; + + 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.finish (); + + 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.array[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<OT::OpenTypeFontFile> (); + + 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<hb_tag_t> tags_supplier (&data->tables[0].tag, table_count, sizeof (data->tables[0])); + OT::Supplier<hb_blob_t *> 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_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 (); + if (unlikely (!entry)) + return false; + + 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<const OT::glyf> (plan); + break; + case HB_OT_TAG_hdmx: + result = _subset<const OT::hdmx> (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<const OT::hmtx> (plan); + break; + case HB_OT_TAG_maxp: + result = _subset<const OT::maxp> (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<const OT::cmap> (plan); + break; + case HB_OT_TAG_os2: + result = _subset<const OT::os2> (plan); + break; + default: + hb_blob_t *source_table = hb_face_reference_table(plan->source, tag); + if (likely (source_table)) + result = hb_subset_plan_add_table(plan, 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; + case HB_TAG ('G', 'D', 'E', 'F'): /* temporary */ + case HB_TAG ('G', 'P', 'O', 'S'): /* temporary */ + case HB_TAG ('G', 'S', 'U', 'B'): /* temporary */ + case HB_TAG ('D', 'S', 'I', 'G'): + 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); + } + } 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; +} |