/* * Copyright © 2018 Adobe 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. * * Adobe Author(s): Michiharu Ariza */ #ifndef HB_SUBSET_CFF_COMMON_HH #define HB_SUBSET_CFF_COMMON_HH #include "hb.hh" #include "hb-subset-plan.hh" #include "hb-cff-interp-cs-common.hh" namespace CFF { /* Used for writing a temporary charstring */ struct str_encoder_t { str_encoder_t (str_buff_t &buff_) : buff (buff_) {} void reset () { buff.reset (); } void encode_byte (unsigned char b) { if (likely ((signed) buff.length < buff.allocated)) buff.arrayZ[buff.length++] = b; else buff.push (b); } void encode_int (int v) { if ((-1131 <= v) && (v <= 1131)) { if ((-107 <= v) && (v <= 107)) encode_byte (v + 139); else if (v > 0) { v -= 108; encode_byte ((v >> 8) + OpCode_TwoBytePosInt0); encode_byte (v & 0xFF); } else { v = -v - 108; encode_byte ((v >> 8) + OpCode_TwoByteNegInt0); encode_byte (v & 0xFF); } } else { if (unlikely (v < -32768)) v = -32768; else if (unlikely (v > 32767)) v = 32767; encode_byte (OpCode_shortint); encode_byte ((v >> 8) & 0xFF); encode_byte (v & 0xFF); } } // Encode number for CharString void encode_num_cs (const number_t& n) { if (n.in_int_range ()) { encode_int (n.to_int ()); } else { int32_t v = n.to_fixed (); encode_byte (OpCode_fixedcs); encode_byte ((v >> 24) & 0xFF); encode_byte ((v >> 16) & 0xFF); encode_byte ((v >> 8) & 0xFF); encode_byte (v & 0xFF); } } // Encode number for TopDict / Private void encode_num_tp (const number_t& n) { if (n.in_int_range ()) { // TODO longint encode_int (n.to_int ()); } else { // Sigh. BCD // https://learn.microsoft.com/en-us/typography/opentype/spec/cff2#table-5-nibble-definitions double v = n.to_real (); encode_byte (OpCode_BCD); // Based on: // https://github.com/fonttools/fonttools/blob/0738c41dfbcbc213ab9263f486ef0cccc6eb5ce5/Lib/fontTools/misc/psCharStrings.py#L267-L316 char buf[16]; /* FontTools has the following comment: * * # Note: 14 decimal digits seems to be the limitation for CFF real numbers * # in macOS. However, we use 8 here to match the implementation of AFDKO. * * We use 8 here to match FontTools X-). */ hb_locale_t clocale HB_UNUSED; hb_locale_t oldlocale HB_UNUSED; oldlocale = hb_uselocale (clocale = newlocale (LC_ALL_MASK, "C", NULL)); snprintf (buf, sizeof (buf), "%.8G", v); (void) hb_uselocale (((void) freelocale (clocale), oldlocale)); char *s = buf; size_t len; char *comma = strchr (s, ','); if (comma) // Comma for some European locales in case no uselocale available. *comma = '.'; if (s[0] == '0' && s[1] == '.') s++; else if (s[0] == '-' && s[1] == '0' && s[2] == '.') { s[1] = '-'; s++; } else if ((len = strlen (s)) > 3 && !strcmp (s + len - 3, "000")) { unsigned exponent = len - 3; char *s2 = s + exponent - 1; while (*s2 == '0' && exponent > 1) { s2--; exponent++; } snprintf (s2 + 1, sizeof (buf) - (s2 + 1 - buf), "E%u", exponent); } else { char *dot = strchr (s, '.'); char *e = strchr (s, 'E'); if (dot && e) { memmove (dot, dot + 1, e - (dot + 1)); int exponent = atoi (e + 1); int new_exponent = exponent - (e - (dot + 1)); if (new_exponent == 1) { e[-1] = '0'; e[0] = '\0'; } else snprintf (e - 1, sizeof (buf) - (e - 1 - buf), "E%d", new_exponent); } } if ((s[0] == '.' && s[1] == '0') || (s[0] == '-' && s[1] == '.' && s[2] == '0')) { int sign = s[0] == '-'; char *s2 = s + sign + 1; while (*s2 == '0') s2++; len = strlen (s2); memmove (s + sign, s2, len); snprintf (s + sign + len, sizeof (buf) - (s + sign + len - buf), "E-%u", (unsigned) (strlen (s + sign) - 1)); } hb_vector_t nibbles; while (*s) { char c = s[0]; s++; switch (c) { case 'E': { char c2 = *s; if (c2 == '-') { s++; nibbles.push (0x0C); // E- } else { if (c2 == '+') s++; nibbles.push (0x0B); // E } if (*s == '0') s++; continue; } case '.': nibbles.push (0x0A); // . continue; case '-': nibbles.push (0x0E); // - continue; } nibbles.push (c - '0'); } nibbles.push (0x0F); if (nibbles.length % 2) nibbles.push (0x0F); unsigned count = nibbles.length; for (unsigned i = 0; i < count; i += 2) encode_byte ((nibbles[i] << 4) | nibbles[i+1]); } } void encode_op (op_code_t op) { if (Is_OpCode_ESC (op)) { encode_byte (OpCode_escape); encode_byte (Unmake_OpCode_ESC (op)); } else encode_byte (op); } void copy_str (const unsigned char *str, unsigned length) { assert ((signed) (buff.length + length) <= buff.allocated); hb_memcpy (buff.arrayZ + buff.length, str, length); buff.length += length; } bool in_error () const { return buff.in_error (); } protected: str_buff_t &buff; }; struct cff_sub_table_info_t { cff_sub_table_info_t () : fd_array_link (0), char_strings_link (0) { fd_select.init (); } table_info_t fd_select; objidx_t fd_array_link; objidx_t char_strings_link; }; template struct cff_top_dict_op_serializer_t : op_serializer_t { bool serialize (hb_serialize_context_t *c, const OPSTR &opstr, const cff_sub_table_info_t &info) const { TRACE_SERIALIZE (this); switch (opstr.op) { case OpCode_CharStrings: return_trace (FontDict::serialize_link4_op(c, opstr.op, info.char_strings_link, whence_t::Absolute)); case OpCode_FDArray: return_trace (FontDict::serialize_link4_op(c, opstr.op, info.fd_array_link, whence_t::Absolute)); case OpCode_FDSelect: return_trace (FontDict::serialize_link4_op(c, opstr.op, info.fd_select.link, whence_t::Absolute)); default: return_trace (copy_opstr (c, opstr)); } return_trace (true); } }; struct cff_font_dict_op_serializer_t : op_serializer_t { bool serialize (hb_serialize_context_t *c, const op_str_t &opstr, const table_info_t &privateDictInfo) const { TRACE_SERIALIZE (this); if (opstr.op == OpCode_Private) { /* serialize the private dict size & offset as 2-byte & 4-byte integers */ return_trace (UnsizedByteStr::serialize_int2 (c, privateDictInfo.size) && Dict::serialize_link4_op (c, opstr.op, privateDictInfo.link, whence_t::Absolute)); } else { unsigned char *d = c->allocate_size (opstr.length); if (unlikely (!d)) return_trace (false); /* Faster than hb_memcpy for small strings. */ for (unsigned i = 0; i < opstr.length; i++) d[i] = opstr.ptr[i]; //hb_memcpy (d, opstr.ptr, opstr.length); } return_trace (true); } }; struct flatten_param_t { str_buff_t &flatStr; bool drop_hints; const hb_subset_plan_t *plan; }; template struct subr_flattener_t { subr_flattener_t (const ACC &acc_, const hb_subset_plan_t *plan_) : acc (acc_), plan (plan_) {} bool flatten (str_buff_vec_t &flat_charstrings) { unsigned count = plan->num_output_glyphs (); if (!flat_charstrings.resize_exact (count)) return false; for (unsigned int i = 0; i < count; i++) { hb_codepoint_t glyph; if (!plan->old_gid_for_new_gid (i, &glyph)) { /* add an endchar only charstring for a missing glyph if CFF1 */ if (endchar_op != OpCode_Invalid) flat_charstrings[i].push (endchar_op); continue; } const hb_ubytes_t str = (*acc.charStrings)[glyph]; unsigned int fd = acc.fdSelect->get_fd (glyph); if (unlikely (fd >= acc.fdCount)) return false; ENV env (str, acc, fd, plan->normalized_coords.arrayZ, plan->normalized_coords.length); cs_interpreter_t interp (env); flatten_param_t param = { flat_charstrings.arrayZ[i], (bool) (plan->flags & HB_SUBSET_FLAGS_NO_HINTING), plan }; if (unlikely (!interp.interpret (param))) return false; } return true; } const ACC &acc; const hb_subset_plan_t *plan; }; struct subr_closures_t { subr_closures_t (unsigned int fd_count) : global_closure (), local_closures () { local_closures.resize_exact (fd_count); } void reset () { global_closure.clear(); for (unsigned int i = 0; i < local_closures.length; i++) local_closures[i].clear(); } bool in_error () const { return local_closures.in_error (); } hb_set_t global_closure; hb_vector_t local_closures; }; struct parsed_cs_op_t : op_str_t { parsed_cs_op_t (unsigned int subr_num_ = 0) : subr_num (subr_num_) {} bool is_hinting () const { return hinting_flag; } void set_hinting () { hinting_flag = true; } /* The layout of this struct is designed to fit within the * padding of op_str_t! */ protected: bool hinting_flag = false; public: uint16_t subr_num; }; struct parsed_cs_str_t : parsed_values_t { parsed_cs_str_t () : parsed (false), hint_dropped (false), has_prefix_ (false), has_calls_ (false) { SUPER::init (); } void add_op (op_code_t op, const byte_str_ref_t& str_ref) { if (!is_parsed ()) SUPER::add_op (op, str_ref); } void add_call_op (op_code_t op, const byte_str_ref_t& str_ref, unsigned int subr_num) { if (!is_parsed ()) { has_calls_ = true; /* Pop the subroutine number. */ values.pop (); SUPER::add_op (op, str_ref, {subr_num}); } } void set_prefix (const number_t &num, op_code_t op = OpCode_Invalid) { has_prefix_ = true; prefix_op_ = op; prefix_num_ = num; } bool at_end (unsigned int pos) const { return ((pos + 1 >= values.length) /* CFF2 */ || (values[pos + 1].op == OpCode_return)); } bool is_parsed () const { return parsed; } void set_parsed () { parsed = true; } bool is_hint_dropped () const { return hint_dropped; } void set_hint_dropped () { hint_dropped = true; } bool is_vsindex_dropped () const { return vsindex_dropped; } void set_vsindex_dropped () { vsindex_dropped = true; } bool has_prefix () const { return has_prefix_; } op_code_t prefix_op () const { return prefix_op_; } const number_t &prefix_num () const { return prefix_num_; } bool has_calls () const { return has_calls_; } void compact () { unsigned count = values.length; if (!count) return; auto &opstr = values.arrayZ; unsigned j = 0; for (unsigned i = 1; i < count; i++) { /* See if we can combine op j and op i. */ bool combine = (opstr[j].op != OpCode_callsubr && opstr[j].op != OpCode_callgsubr) && (opstr[i].op != OpCode_callsubr && opstr[i].op != OpCode_callgsubr) && (opstr[j].is_hinting () == opstr[i].is_hinting ()) && (opstr[j].ptr + opstr[j].length == opstr[i].ptr) && (opstr[j].length + opstr[i].length <= 255); if (combine) { opstr[j].length += opstr[i].length; opstr[j].op = OpCode_Invalid; } else { opstr[++j] = opstr[i]; } } values.shrink (j + 1); } protected: bool parsed : 1; bool hint_dropped : 1; bool vsindex_dropped : 1; bool has_prefix_ : 1; bool has_calls_ : 1; op_code_t prefix_op_; number_t prefix_num_; private: typedef parsed_values_t SUPER; }; struct parsed_cs_str_vec_t : hb_vector_t { private: typedef hb_vector_t SUPER; }; struct cff_subset_accelerator_t { static cff_subset_accelerator_t* create ( hb_blob_t* original_blob, const parsed_cs_str_vec_t& parsed_charstrings, const parsed_cs_str_vec_t& parsed_global_subrs, const hb_vector_t& parsed_local_subrs) { cff_subset_accelerator_t* accel = (cff_subset_accelerator_t*) hb_malloc (sizeof(cff_subset_accelerator_t)); if (unlikely (!accel)) return nullptr; new (accel) cff_subset_accelerator_t (original_blob, parsed_charstrings, parsed_global_subrs, parsed_local_subrs); return accel; } static void destroy (void* value) { if (!value) return; cff_subset_accelerator_t* accel = (cff_subset_accelerator_t*) value; accel->~cff_subset_accelerator_t (); hb_free (accel); } cff_subset_accelerator_t( hb_blob_t* original_blob_, const parsed_cs_str_vec_t& parsed_charstrings_, const parsed_cs_str_vec_t& parsed_global_subrs_, const hb_vector_t& parsed_local_subrs_) { parsed_charstrings = parsed_charstrings_; parsed_global_subrs = parsed_global_subrs_; parsed_local_subrs = parsed_local_subrs_; // the parsed charstrings point to memory in the original CFF table so we must hold a reference // to it to keep the memory valid. original_blob = hb_blob_reference (original_blob_); } ~cff_subset_accelerator_t() { hb_blob_destroy (original_blob); auto *mapping = glyph_to_sid_map.get_relaxed (); if (mapping) { mapping->~glyph_to_sid_map_t (); hb_free (mapping); } } parsed_cs_str_vec_t parsed_charstrings; parsed_cs_str_vec_t parsed_global_subrs; hb_vector_t parsed_local_subrs; mutable hb_atomic_ptr_t glyph_to_sid_map; private: hb_blob_t* original_blob; }; struct subr_subset_param_t { subr_subset_param_t (parsed_cs_str_t *parsed_charstring_, parsed_cs_str_vec_t *parsed_global_subrs_, parsed_cs_str_vec_t *parsed_local_subrs_, hb_set_t *global_closure_, hb_set_t *local_closure_, bool drop_hints_) : current_parsed_str (parsed_charstring_), parsed_charstring (parsed_charstring_), parsed_global_subrs (parsed_global_subrs_), parsed_local_subrs (parsed_local_subrs_), global_closure (global_closure_), local_closure (local_closure_), drop_hints (drop_hints_) {} parsed_cs_str_t *get_parsed_str_for_context (call_context_t &context) { switch (context.type) { case CSType_CharString: return parsed_charstring; case CSType_LocalSubr: if (likely (context.subr_num < parsed_local_subrs->length)) return &(*parsed_local_subrs)[context.subr_num]; break; case CSType_GlobalSubr: if (likely (context.subr_num < parsed_global_subrs->length)) return &(*parsed_global_subrs)[context.subr_num]; break; } return nullptr; } template void set_current_str (ENV &env, bool calling) { parsed_cs_str_t *parsed_str = get_parsed_str_for_context (env.context); if (unlikely (!parsed_str)) { env.set_error (); return; } /* If the called subroutine is parsed partially but not completely yet, * it must be because we are calling it recursively. * Handle it as an error. */ if (unlikely (calling && !parsed_str->is_parsed () && (parsed_str->values.length > 0))) env.set_error (); else { if (!parsed_str->is_parsed ()) parsed_str->alloc (env.str_ref.total_size ()); current_parsed_str = parsed_str; } } parsed_cs_str_t *current_parsed_str; parsed_cs_str_t *parsed_charstring; parsed_cs_str_vec_t *parsed_global_subrs; parsed_cs_str_vec_t *parsed_local_subrs; hb_set_t *global_closure; hb_set_t *local_closure; bool drop_hints; }; struct subr_remap_t : hb_inc_bimap_t { void create (const hb_set_t *closure) { /* create a remapping of subroutine numbers from old to new. * no optimization based on usage counts. fonttools doesn't appear doing that either. */ alloc (closure->get_population ()); for (auto old_num : *closure) add (old_num); if (get_population () < 1240) bias = 107; else if (get_population () < 33900) bias = 1131; else bias = 32768; } int biased_num (unsigned int old_num) const { hb_codepoint_t new_num = get (old_num); return (int)new_num - bias; } protected: int bias; }; struct subr_remaps_t { subr_remaps_t (unsigned int fdCount) { local_remaps.resize (fdCount); } bool in_error() { return local_remaps.in_error (); } void create (subr_closures_t& closures) { global_remap.create (&closures.global_closure); for (unsigned int i = 0; i < local_remaps.length; i++) local_remaps.arrayZ[i].create (&closures.local_closures[i]); } subr_remap_t global_remap; hb_vector_t local_remaps; }; template struct subr_subsetter_t { subr_subsetter_t (ACC &acc_, const hb_subset_plan_t *plan_) : acc (acc_), plan (plan_), closures(acc_.fdCount), remaps(acc_.fdCount) {} /* Subroutine subsetting with --no-desubroutinize runs in phases: * * 1. execute charstrings/subroutines to determine subroutine closures * 2. parse out all operators and numbers * 3. mark hint operators and operands for removal if --no-hinting * 4. re-encode all charstrings and subroutines with new subroutine numbers * * Phases #1 and #2 are done at the same time in collect_subrs (). * Phase #3 walks charstrings/subroutines forward then backward (hence parsing required), * because we can't tell if a number belongs to a hint op until we see the first moveto. * * Assumption: a callsubr/callgsubr operator must immediately follow a (biased) subroutine number * within the same charstring/subroutine, e.g., not split across a charstring and a subroutine. */ bool subset (void) { unsigned fd_count = acc.fdCount; const cff_subset_accelerator_t* cff_accelerator = nullptr; if (acc.cff_accelerator) { cff_accelerator = acc.cff_accelerator; fd_count = cff_accelerator->parsed_local_subrs.length; } if (cff_accelerator) { // If we are not dropping hinting then charstrings are not modified so we can // just use a reference to the cached copies. cached_charstrings.resize_exact (plan->num_output_glyphs ()); parsed_global_subrs = &cff_accelerator->parsed_global_subrs; parsed_local_subrs = &cff_accelerator->parsed_local_subrs; } else { parsed_charstrings.resize_exact (plan->num_output_glyphs ()); parsed_global_subrs_storage.resize_exact (acc.globalSubrs->count); if (unlikely (!parsed_local_subrs_storage.resize (fd_count))) return false; for (unsigned int i = 0; i < acc.fdCount; i++) { unsigned count = acc.privateDicts[i].localSubrs->count; parsed_local_subrs_storage[i].resize (count); if (unlikely (parsed_local_subrs_storage[i].in_error ())) return false; } parsed_global_subrs = &parsed_global_subrs_storage; parsed_local_subrs = &parsed_local_subrs_storage; } if (unlikely (remaps.in_error() || cached_charstrings.in_error () || parsed_charstrings.in_error () || parsed_global_subrs->in_error () || closures.in_error ())) { return false; } /* phase 1 & 2 */ for (auto _ : plan->new_to_old_gid_list) { hb_codepoint_t new_glyph = _.first; hb_codepoint_t old_glyph = _.second; const hb_ubytes_t str = (*acc.charStrings)[old_glyph]; unsigned int fd = acc.fdSelect->get_fd (old_glyph); if (unlikely (fd >= acc.fdCount)) return false; if (cff_accelerator) { // parsed string already exists in accelerator, copy it and move // on. if (cached_charstrings) cached_charstrings[new_glyph] = &cff_accelerator->parsed_charstrings[old_glyph]; else parsed_charstrings[new_glyph] = cff_accelerator->parsed_charstrings[old_glyph]; continue; } ENV env (str, acc, fd); cs_interpreter_t interp (env); parsed_charstrings[new_glyph].alloc (str.length); subr_subset_param_t param (&parsed_charstrings[new_glyph], &parsed_global_subrs_storage, &parsed_local_subrs_storage[fd], &closures.global_closure, &closures.local_closures[fd], plan->flags & HB_SUBSET_FLAGS_NO_HINTING); if (unlikely (!interp.interpret (param))) return false; /* complete parsed string esp. copy CFF1 width or CFF2 vsindex to the parsed charstring for encoding */ SUBSETTER::complete_parsed_str (interp.env, param, parsed_charstrings[new_glyph]); /* mark hint ops and arguments for drop */ if ((plan->flags & HB_SUBSET_FLAGS_NO_HINTING) || plan->inprogress_accelerator) { subr_subset_param_t param (&parsed_charstrings[new_glyph], &parsed_global_subrs_storage, &parsed_local_subrs_storage[fd], &closures.global_closure, &closures.local_closures[fd], plan->flags & HB_SUBSET_FLAGS_NO_HINTING); drop_hints_param_t drop; if (drop_hints_in_str (parsed_charstrings[new_glyph], param, drop)) { parsed_charstrings[new_glyph].set_hint_dropped (); if (drop.vsindex_dropped) parsed_charstrings[new_glyph].set_vsindex_dropped (); } } /* Doing this here one by one instead of compacting all at the end * has massive peak-memory saving. * * The compacting both saves memory and makes further operations * faster. */ parsed_charstrings[new_glyph].compact (); } /* Since parsed strings were loaded from accelerator, we still need * to compute the subroutine closures which would have normally happened during * parsing. * * Or if we are dropping hinting, redo closure to get actually used subrs. */ if ((cff_accelerator || (!cff_accelerator && plan->flags & HB_SUBSET_FLAGS_NO_HINTING)) && !closure_subroutines(*parsed_global_subrs, *parsed_local_subrs)) return false; remaps.create (closures); populate_subset_accelerator (); return true; } bool encode_charstrings (str_buff_vec_t &buffArray, bool encode_prefix = true) const { unsigned num_glyphs = plan->num_output_glyphs (); if (unlikely (!buffArray.resize_exact (num_glyphs))) return false; hb_codepoint_t last = 0; for (auto _ : plan->new_to_old_gid_list) { hb_codepoint_t gid = _.first; hb_codepoint_t old_glyph = _.second; if (endchar_op != OpCode_Invalid) for (; last < gid; last++) { // Hack to point vector to static string. auto &b = buffArray.arrayZ[last]; b.length = 1; b.arrayZ = const_cast(endchar_str); } last++; // Skip over gid unsigned int fd = acc.fdSelect->get_fd (old_glyph); if (unlikely (fd >= acc.fdCount)) return false; if (unlikely (!encode_str (get_parsed_charstring (gid), fd, buffArray.arrayZ[gid], encode_prefix))) return false; } if (endchar_op != OpCode_Invalid) for (; last < num_glyphs; last++) { // Hack to point vector to static string. auto &b = buffArray.arrayZ[last]; b.length = 1; b.arrayZ = const_cast(endchar_str); } return true; } bool encode_subrs (const parsed_cs_str_vec_t &subrs, const subr_remap_t& remap, unsigned int fd, str_buff_vec_t &buffArray) const { unsigned int count = remap.get_population (); if (unlikely (!buffArray.resize_exact (count))) return false; for (unsigned int new_num = 0; new_num < count; new_num++) { hb_codepoint_t old_num = remap.backward (new_num); assert (old_num != CFF_UNDEF_CODE); if (unlikely (!encode_str (subrs[old_num], fd, buffArray[new_num]))) return false; } return true; } bool encode_globalsubrs (str_buff_vec_t &buffArray) { return encode_subrs (*parsed_global_subrs, remaps.global_remap, 0, buffArray); } bool encode_localsubrs (unsigned int fd, str_buff_vec_t &buffArray) const { return encode_subrs ((*parsed_local_subrs)[fd], remaps.local_remaps[fd], fd, buffArray); } protected: struct drop_hints_param_t { drop_hints_param_t () : seen_moveto (false), ends_in_hint (false), all_dropped (false), vsindex_dropped (false) {} bool seen_moveto; bool ends_in_hint; bool all_dropped; bool vsindex_dropped; }; bool drop_hints_in_subr (parsed_cs_str_t &str, unsigned int pos, parsed_cs_str_vec_t &subrs, unsigned int subr_num, const subr_subset_param_t ¶m, drop_hints_param_t &drop) { drop.ends_in_hint = false; bool has_hint = drop_hints_in_str (subrs[subr_num], param, drop); /* if this subr ends with a stem hint (i.e., not a number; potential argument for moveto), * then this entire subroutine must be a hint. drop its call. */ if (drop.ends_in_hint) { str.values[pos].set_hinting (); /* if this subr call is at the end of the parent subr, propagate the flag * otherwise reset the flag */ if (!str.at_end (pos)) drop.ends_in_hint = false; } else if (drop.all_dropped) { str.values[pos].set_hinting (); } return has_hint; } /* returns true if it sees a hint op before the first moveto */ bool drop_hints_in_str (parsed_cs_str_t &str, const subr_subset_param_t ¶m, drop_hints_param_t &drop) { bool seen_hint = false; unsigned count = str.values.length; auto *values = str.values.arrayZ; for (unsigned int pos = 0; pos < count; pos++) { bool has_hint = false; switch (values[pos].op) { case OpCode_callsubr: has_hint = drop_hints_in_subr (str, pos, *param.parsed_local_subrs, values[pos].subr_num, param, drop); break; case OpCode_callgsubr: has_hint = drop_hints_in_subr (str, pos, *param.parsed_global_subrs, values[pos].subr_num, param, drop); break; case OpCode_rmoveto: case OpCode_hmoveto: case OpCode_vmoveto: drop.seen_moveto = true; break; case OpCode_hintmask: case OpCode_cntrmask: if (drop.seen_moveto) { values[pos].set_hinting (); break; } HB_FALLTHROUGH; case OpCode_hstemhm: case OpCode_vstemhm: case OpCode_hstem: case OpCode_vstem: has_hint = true; values[pos].set_hinting (); if (str.at_end (pos)) drop.ends_in_hint = true; break; case OpCode_dotsection: values[pos].set_hinting (); break; default: /* NONE */ break; } if (has_hint) { for (int i = pos - 1; i >= 0; i--) { parsed_cs_op_t &csop = values[(unsigned)i]; if (csop.is_hinting ()) break; csop.set_hinting (); if (csop.op == OpCode_vsindexcs) drop.vsindex_dropped = true; } seen_hint |= has_hint; } } /* Raise all_dropped flag if all operators except return are dropped from a subr. * It may happen even after seeing the first moveto if a subr contains * only (usually one) hintmask operator, then calls to this subr can be dropped. */ drop.all_dropped = true; for (unsigned int pos = 0; pos < count; pos++) { parsed_cs_op_t &csop = values[pos]; if (csop.op == OpCode_return) break; if (!csop.is_hinting ()) { drop.all_dropped = false; break; } } return seen_hint; } bool closure_subroutines (const parsed_cs_str_vec_t& global_subrs, const hb_vector_t& local_subrs) { closures.reset (); for (auto _ : plan->new_to_old_gid_list) { hb_codepoint_t new_glyph = _.first; hb_codepoint_t old_glyph = _.second; unsigned int fd = acc.fdSelect->get_fd (old_glyph); if (unlikely (fd >= acc.fdCount)) return false; // Note: const cast is safe here because the collect_subr_refs_in_str only performs a // closure and does not modify any of the charstrings. subr_subset_param_t param (const_cast (&get_parsed_charstring (new_glyph)), const_cast (&global_subrs), const_cast (&local_subrs[fd]), &closures.global_closure, &closures.local_closures[fd], plan->flags & HB_SUBSET_FLAGS_NO_HINTING); collect_subr_refs_in_str (get_parsed_charstring (new_glyph), param); } return true; } void collect_subr_refs_in_subr (unsigned int subr_num, parsed_cs_str_vec_t &subrs, hb_set_t *closure, const subr_subset_param_t ¶m) { if (closure->has (subr_num)) return; closure->add (subr_num); collect_subr_refs_in_str (subrs[subr_num], param); } void collect_subr_refs_in_str (const parsed_cs_str_t &str, const subr_subset_param_t ¶m) { if (!str.has_calls ()) return; for (auto &opstr : str.values) { if (!param.drop_hints || !opstr.is_hinting ()) { switch (opstr.op) { case OpCode_callsubr: collect_subr_refs_in_subr (opstr.subr_num, *param.parsed_local_subrs, param.local_closure, param); break; case OpCode_callgsubr: collect_subr_refs_in_subr (opstr.subr_num, *param.parsed_global_subrs, param.global_closure, param); break; default: break; } } } } bool encode_str (const parsed_cs_str_t &str, const unsigned int fd, str_buff_t &buff, bool encode_prefix = true) const { str_encoder_t encoder (buff); encoder.reset (); bool hinting = !(plan->flags & HB_SUBSET_FLAGS_NO_HINTING); /* if a prefix (CFF1 width or CFF2 vsindex) has been removed along with hints, * re-insert it at the beginning of charstreing */ if (encode_prefix && str.has_prefix () && !hinting && str.is_hint_dropped ()) { encoder.encode_num_cs (str.prefix_num ()); if (str.prefix_op () != OpCode_Invalid) encoder.encode_op (str.prefix_op ()); } unsigned size = 0; for (auto &opstr : str.values) { size += opstr.length; if (opstr.op == OpCode_callsubr || opstr.op == OpCode_callgsubr) size += 3; } if (!buff.alloc (buff.length + size, true)) return false; for (auto &opstr : str.values) { if (hinting || !opstr.is_hinting ()) { switch (opstr.op) { case OpCode_callsubr: encoder.encode_int (remaps.local_remaps[fd].biased_num (opstr.subr_num)); encoder.copy_str (opstr.ptr, opstr.length); break; case OpCode_callgsubr: encoder.encode_int (remaps.global_remap.biased_num (opstr.subr_num)); encoder.copy_str (opstr.ptr, opstr.length); break; default: encoder.copy_str (opstr.ptr, opstr.length); break; } } } return !encoder.in_error (); } void compact_parsed_subrs () const { for (auto &cs : parsed_global_subrs_storage) cs.compact (); for (auto &vec : parsed_local_subrs_storage) for (auto &cs : vec) cs.compact (); } void populate_subset_accelerator () const { if (!plan->inprogress_accelerator) return; compact_parsed_subrs (); acc.cff_accelerator = cff_subset_accelerator_t::create(acc.blob, parsed_charstrings, parsed_global_subrs_storage, parsed_local_subrs_storage); } const parsed_cs_str_t& get_parsed_charstring (unsigned i) const { if (cached_charstrings) return *(cached_charstrings[i]); return parsed_charstrings[i]; } protected: const ACC &acc; const hb_subset_plan_t *plan; subr_closures_t closures; hb_vector_t cached_charstrings; const parsed_cs_str_vec_t* parsed_global_subrs; const hb_vector_t* parsed_local_subrs; subr_remaps_t remaps; private: parsed_cs_str_vec_t parsed_charstrings; parsed_cs_str_vec_t parsed_global_subrs_storage; hb_vector_t parsed_local_subrs_storage; typedef typename SUBRS::count_type subr_count_type; }; } /* namespace CFF */ HB_INTERNAL bool hb_plan_subset_cff_fdselect (const hb_subset_plan_t *plan, unsigned int fdCount, const CFF::FDSelect &src, /* IN */ unsigned int &subset_fd_count /* OUT */, unsigned int &subset_fdselect_size /* OUT */, unsigned int &subset_fdselect_format /* OUT */, hb_vector_t &fdselect_ranges /* OUT */, hb_inc_bimap_t &fdmap /* OUT */); HB_INTERNAL bool hb_serialize_cff_fdselect (hb_serialize_context_t *c, unsigned int num_glyphs, const CFF::FDSelect &src, unsigned int fd_count, unsigned int fdselect_format, unsigned int size, const hb_vector_t &fdselect_ranges); #endif /* HB_SUBSET_CFF_COMMON_HH */