/*

 * Copyright © 2011,2014  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): Behdad Esfahbod, Roozbeh Pournader

 */

#include "hb.hh"

#ifndef HB_NO_OT_FONT

#include "hb-ot.h"

#include "hb-cache.hh"

#include "hb-font.hh"

#include "hb-machinery.hh"

#include "hb-ot-face.hh"

#include "hb-outline.hh"

#include "hb-ot-cmap-table.hh"

#include "hb-ot-glyf-table.hh"

#include "hb-ot-cff1-table.hh"

#include "hb-ot-cff2-table.hh"

#include "hb-ot-hmtx-table.hh"

#include "hb-ot-post-table.hh"

#include "hb-ot-stat-table.hh" // Just so we compile it; unused otherwise.

#include "hb-ot-vorg-table.hh"

#include "OT/Color/CBDT/CBDT.hh"

#include "OT/Color/COLR/COLR.hh"

#include "OT/Color/sbix/sbix.hh"

#include "OT/Color/svg/svg.hh"

/**

 * SECTION:hb-ot-font

 * @title: hb-ot-font

 * @short_description: OpenType font implementation

 * @include: hb-ot.h

 *

 * Functions for using OpenType fonts with hb_shape().  Note that fonts returned

 * by hb_font_create() default to using these functions, so most clients would

 * never need to call these functions directly.

 **/

using hb_ot_font_cmap_cache_t    = hb_cache_t<21, 16, 8, true>;

using hb_ot_font_advance_cache_t = hb_cache_t<24, 16, 8, true>;

#ifndef HB_NO_OT_FONT_CMAP_CACHE

static hb_user_data_key_t hb_ot_font_cmap_cache_user_data_key;

#endif

struct hb_ot_font_t

{

  const hb_ot_face_t *ot_face;

#ifndef HB_NO_OT_FONT_CMAP_CACHE

  hb_ot_font_cmap_cache_t *cmap_cache;

#endif

  /* h_advance caching */

  mutable hb_atomic_int_t cached_coords_serial;

  mutable hb_atomic_ptr_t<hb_ot_font_advance_cache_t> advance_cache;

};

static hb_ot_font_t *

_hb_ot_font_create (hb_font_t *font)

{

  hb_ot_font_t *ot_font = (hb_ot_font_t *) hb_calloc (1, sizeof (hb_ot_font_t));

  if (unlikely (!ot_font))

    return nullptr;

  ot_font->ot_face = &font->face->table;

#ifndef HB_NO_OT_FONT_CMAP_CACHE

  // retry:

  auto *cmap_cache  = (hb_ot_font_cmap_cache_t *) hb_face_get_user_data (font->face,

                   &hb_ot_font_cmap_cache_user_data_key);

  if (!cmap_cache)

  {

    cmap_cache = (hb_ot_font_cmap_cache_t *) hb_malloc (sizeof (hb_ot_font_cmap_cache_t));

    if (unlikely (!cmap_cache)) goto out;

    cmap_cache->init ();

    if (unlikely (!hb_face_set_user_data (font->face,

            &hb_ot_font_cmap_cache_user_data_key,

            cmap_cache,

            hb_free,

            false)))

    {

      hb_free (cmap_cache);

      cmap_cache = nullptr;

      /* Normally we would retry here, but that would

       * infinite-loop if the face is the empty-face.

       * Just let it go and this font will be uncached if it

       * happened to collide with another thread creating the

       * cache at the same time. */

      // goto retry;

    }

  }

  out:

  ot_font->cmap_cache = cmap_cache;

#endif

  return ot_font;

}

static void

_hb_ot_font_destroy (void *font_data)

{

  hb_ot_font_t *ot_font = (hb_ot_font_t *) font_data;

  auto *cache = ot_font->advance_cache.get_relaxed ();

  hb_free (cache);

  hb_free (ot_font);

}

static hb_bool_t

hb_ot_get_nominal_glyph (hb_font_t *font HB_UNUSED,

       void *font_data,

       hb_codepoint_t unicode,

       hb_codepoint_t *glyph,

       void *user_data HB_UNUSED)

{

  const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data;

  const hb_ot_face_t *ot_face = ot_font->ot_face;

  hb_ot_font_cmap_cache_t *cmap_cache = nullptr;

#ifndef HB_NO_OT_FONT_CMAP_CACHE

  cmap_cache = ot_font->cmap_cache;

#endif

  return ot_face->cmap->get_nominal_glyph (unicode, glyph, cmap_cache);

}

static unsigned int

hb_ot_get_nominal_glyphs (hb_font_t *font HB_UNUSED,

        void *font_data,

        unsigned int count,

        const hb_codepoint_t *first_unicode,

        unsigned int unicode_stride,

        hb_codepoint_t *first_glyph,

        unsigned int glyph_stride,

        void *user_data HB_UNUSED)

{

  const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data;

  const hb_ot_face_t *ot_face = ot_font->ot_face;

  hb_ot_font_cmap_cache_t *cmap_cache = nullptr;

#ifndef HB_NO_OT_FONT_CMAP_CACHE

  cmap_cache = ot_font->cmap_cache;

#endif

  return ot_face->cmap->get_nominal_glyphs (count,

              first_unicode, unicode_stride,

              first_glyph, glyph_stride,

              cmap_cache);

}

static hb_bool_t

hb_ot_get_variation_glyph (hb_font_t *font HB_UNUSED,

         void *font_data,

         hb_codepoint_t unicode,

         hb_codepoint_t variation_selector,

         hb_codepoint_t *glyph,

         void *user_data HB_UNUSED)

{

  const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data;

  const hb_ot_face_t *ot_face = ot_font->ot_face;

  hb_ot_font_cmap_cache_t *cmap_cache = nullptr;

#ifndef HB_NO_OT_FONT_CMAP_CACHE

  cmap_cache = ot_font->cmap_cache;

#endif

  return ot_face->cmap->get_variation_glyph (unicode,

                                             variation_selector, glyph,

                                             cmap_cache);

}

static void

hb_ot_get_glyph_h_advances (hb_font_t* font, void* font_data,

          unsigned count,

          const hb_codepoint_t *first_glyph,

          unsigned glyph_stride,

          hb_position_t *first_advance,

          unsigned advance_stride,

          void *user_data HB_UNUSED)

{

  const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data;

  const hb_ot_face_t *ot_face = ot_font->ot_face;

  const OT::hmtx_accelerator_t &hmtx = *ot_face->hmtx;

  hb_position_t *orig_first_advance = first_advance;

#if !defined(HB_NO_VAR) && !defined(HB_NO_OT_FONT_ADVANCE_CACHE)

  const OT::HVAR &HVAR = *hmtx.var_table;

  const OT::VariationStore &varStore = &HVAR + HVAR.varStore;

  OT::VariationStore::cache_t *varStore_cache = font->num_coords * count >= 128 ? varStore.create_cache () : nullptr;

  bool use_cache = font->num_coords;

#else

  OT::VariationStore::cache_t *varStore_cache = nullptr;

  bool use_cache = false;

#endif

  hb_ot_font_advance_cache_t *cache = nullptr;

  if (use_cache)

  {

  retry:

    cache = ot_font->advance_cache.get_acquire ();

    if (unlikely (!cache))

    {

      cache = (hb_ot_font_advance_cache_t *) hb_malloc (sizeof (hb_ot_font_advance_cache_t));

      if (unlikely (!cache))

      {

  use_cache = false;

  goto out;

      }

      cache->init ();

      if (unlikely (!ot_font->advance_cache.cmpexch (nullptr, cache)))

      {

  hb_free (cache);

  goto retry;

      }

      ot_font->cached_coords_serial.set_release (font->serial_coords);

    }

  }

  out:

  if (!use_cache)

  {

    for (unsigned int i = 0; i < count; i++)

    {

      *first_advance = font->em_scale_x (hmtx.get_advance_with_var_unscaled (*first_glyph, font, varStore_cache));

      first_glyph = &StructAtOffsetUnaligned<hb_codepoint_t> (first_glyph, glyph_stride);

      first_advance = &StructAtOffsetUnaligned<hb_position_t> (first_advance, advance_stride);

    }

  }

  else

  { /* Use cache. */

    if (ot_font->cached_coords_serial.get_acquire () != (int) font->serial_coords)

    {

      ot_font->advance_cache->init ();

      ot_font->cached_coords_serial.set_release (font->serial_coords);

    }

    for (unsigned int i = 0; i < count; i++)

    {

      hb_position_t v;

      unsigned cv;

      if (ot_font->advance_cache->get (*first_glyph, &cv))

  v = cv;

      else

      {

        v = hmtx.get_advance_with_var_unscaled (*first_glyph, font, varStore_cache);

  ot_font->advance_cache->set (*first_glyph, v);

      }

      *first_advance = font->em_scale_x (v);

      first_glyph = &StructAtOffsetUnaligned<hb_codepoint_t> (first_glyph, glyph_stride);

      first_advance = &StructAtOffsetUnaligned<hb_position_t> (first_advance, advance_stride);

    }

  }

#if !defined(HB_NO_VAR) && !defined(HB_NO_OT_FONT_ADVANCE_CACHE)

  OT::VariationStore::destroy_cache (varStore_cache);

#endif

  if (font->x_strength && !font->embolden_in_place)

  {

    /* Emboldening. */

    hb_position_t x_strength = font->x_scale >= 0 ? font->x_strength : -font->x_strength;

    first_advance = orig_first_advance;

    for (unsigned int i = 0; i < count; i++)

    {

      *first_advance += *first_advance ? x_strength : 0;

      first_advance = &StructAtOffsetUnaligned<hb_position_t> (first_advance, advance_stride);

    }

  }

}

#ifndef HB_NO_VERTICAL

static void

hb_ot_get_glyph_v_advances (hb_font_t* font, void* font_data,

          unsigned count,

          const hb_codepoint_t *first_glyph,

          unsigned glyph_stride,

          hb_position_t *first_advance,

          unsigned advance_stride,

          void *user_data HB_UNUSED)

{

  const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data;

  const hb_ot_face_t *ot_face = ot_font->ot_face;

  const OT::vmtx_accelerator_t &vmtx = *ot_face->vmtx;

  hb_position_t *orig_first_advance = first_advance;

  if (vmtx.has_data ())

  {

#if !defined(HB_NO_VAR) && !defined(HB_NO_OT_FONT_ADVANCE_CACHE)

    const OT::VVAR &VVAR = *vmtx.var_table;

    const OT::VariationStore &varStore = &VVAR + VVAR.varStore;

    OT::VariationStore::cache_t *varStore_cache = font->num_coords ? varStore.create_cache () : nullptr;

#else

    OT::VariationStore::cache_t *varStore_cache = nullptr;

#endif

    for (unsigned int i = 0; i < count; i++)

    {

      *first_advance = font->em_scale_y (-(int) vmtx.get_advance_with_var_unscaled (*first_glyph, font, varStore_cache));

      first_glyph = &StructAtOffsetUnaligned<hb_codepoint_t> (first_glyph, glyph_stride);

      first_advance = &StructAtOffsetUnaligned<hb_position_t> (first_advance, advance_stride);

    }

#if !defined(HB_NO_VAR) && !defined(HB_NO_OT_FONT_ADVANCE_CACHE)

    OT::VariationStore::destroy_cache (varStore_cache);

#endif

  }

  else

  {

    hb_font_extents_t font_extents;

    font->get_h_extents_with_fallback (&font_extents);

    hb_position_t advance = -(font_extents.ascender - font_extents.descender);

    for (unsigned int i = 0; i < count; i++)

    {

      *first_advance = advance;

      first_glyph = &StructAtOffsetUnaligned<hb_codepoint_t> (first_glyph, glyph_stride);

      first_advance = &StructAtOffsetUnaligned<hb_position_t> (first_advance, advance_stride);

    }

  }

  if (font->y_strength && !font->embolden_in_place)

  {

    /* Emboldening. */

    hb_position_t y_strength = font->y_scale >= 0 ? font->y_strength : -font->y_strength;

    first_advance = orig_first_advance;

    for (unsigned int i = 0; i < count; i++)

    {

      *first_advance += *first_advance ? y_strength : 0;

      first_advance = &StructAtOffsetUnaligned<hb_position_t> (first_advance, advance_stride);

    }

  }

}

#endif

#ifndef HB_NO_VERTICAL

static hb_bool_t

hb_ot_get_glyph_v_origin (hb_font_t *font,

        void *font_data,

        hb_codepoint_t glyph,

        hb_position_t *x,

        hb_position_t *y,

        void *user_data HB_UNUSED)

{

  const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data;

  const hb_ot_face_t *ot_face = ot_font->ot_face;

  *x = font->get_glyph_h_advance (glyph) / 2;

  const OT::VORG &VORG = *ot_face->VORG;

  if (VORG.has_data ())

  {

    float delta = 0;

#ifndef HB_NO_VAR

    const OT::vmtx_accelerator_t &vmtx = *ot_face->vmtx;

    const OT::VVAR &VVAR = *vmtx.var_table;

    if (font->num_coords)

      VVAR.get_vorg_delta_unscaled (glyph,

            font->coords, font->num_coords,

            &delta);

#endif

    *y = font->em_scalef_y (VORG.get_y_origin (glyph) + delta);

    return true;

  }

  hb_glyph_extents_t extents = {0};

  if (ot_face->glyf->get_extents (font, glyph, &extents))

  {

    const OT::vmtx_accelerator_t &vmtx = *ot_face->vmtx;

    int tsb = 0;

    if (vmtx.get_leading_bearing_with_var_unscaled (font, glyph, &tsb))

    {

      *y = extents.y_bearing + font->em_scale_y (tsb);

      return true;

    }

    hb_font_extents_t font_extents;

    font->get_h_extents_with_fallback (&font_extents);

    hb_position_t advance = font_extents.ascender - font_extents.descender;

    int diff = advance - -extents.height;

    *y = extents.y_bearing + (diff >> 1);

    return true;

  }

  hb_font_extents_t font_extents;

  font->get_h_extents_with_fallback (&font_extents);

  *y = font_extents.ascender;

  return true;

}

#endif

static hb_bool_t

hb_ot_get_glyph_extents (hb_font_t *font,

       void *font_data,

       hb_codepoint_t glyph,

       hb_glyph_extents_t *extents,

       void *user_data HB_UNUSED)

{

  const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data;

  const hb_ot_face_t *ot_face = ot_font->ot_face;

#if !defined(HB_NO_OT_FONT_BITMAP) && !defined(HB_NO_COLOR)

  if (ot_face->sbix->get_extents (font, glyph, extents)) return true;

  if (ot_face->CBDT->get_extents (font, glyph, extents)) return true;

#endif

#if !defined(HB_NO_COLOR) && !defined(HB_NO_PAINT)

  if (ot_face->COLR->get_extents (font, glyph, extents)) return true;

#endif

  if (ot_face->glyf->get_extents (font, glyph, extents)) return true;

#ifndef HB_NO_OT_FONT_CFF

  if (ot_face->cff1->get_extents (font, glyph, extents)) return true;

  if (ot_face->cff2->get_extents (font, glyph, extents)) return true;

#endif

  return false;

}

#ifndef HB_NO_OT_FONT_GLYPH_NAMES

static hb_bool_t

hb_ot_get_glyph_name (hb_font_t *font HB_UNUSED,

          void *font_data,

          hb_codepoint_t glyph,

          char *name, unsigned int size,

          void *user_data HB_UNUSED)

{

  const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data;

  const hb_ot_face_t *ot_face = ot_font->ot_face;

  if (ot_face->post->get_glyph_name (glyph, name, size)) return true;

#ifndef HB_NO_OT_FONT_CFF

  if (ot_face->cff1->get_glyph_name (glyph, name, size)) return true;

#endif

  return false;

}

static hb_bool_t

hb_ot_get_glyph_from_name (hb_font_t *font HB_UNUSED,

         void *font_data,

         const char *name, int len,

         hb_codepoint_t *glyph,

         void *user_data HB_UNUSED)

{

  const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data;

  const hb_ot_face_t *ot_face = ot_font->ot_face;

  if (ot_face->post->get_glyph_from_name (name, len, glyph)) return true;

#ifndef HB_NO_OT_FONT_CFF

    if (ot_face->cff1->get_glyph_from_name (name, len, glyph)) return true;

#endif

  return false;

}

#endif

static hb_bool_t

hb_ot_get_font_h_extents (hb_font_t *font,

        void *font_data HB_UNUSED,

        hb_font_extents_t *metrics,

        void *user_data HB_UNUSED)

{

  bool ret = _hb_ot_metrics_get_position_common (font, HB_OT_METRICS_TAG_HORIZONTAL_ASCENDER, &metrics->ascender) &&

       _hb_ot_metrics_get_position_common (font, HB_OT_METRICS_TAG_HORIZONTAL_DESCENDER, &metrics->descender) &&

       _hb_ot_metrics_get_position_common (font, HB_OT_METRICS_TAG_HORIZONTAL_LINE_GAP, &metrics->line_gap);

  /* Embolden */

  int y_shift = font->y_strength;

  if (font->y_scale < 0) y_shift = -y_shift;

  metrics->ascender += y_shift;

  return ret;

}

#ifndef HB_NO_VERTICAL

static hb_bool_t

hb_ot_get_font_v_extents (hb_font_t *font,

        void *font_data HB_UNUSED,

        hb_font_extents_t *metrics,

        void *user_data HB_UNUSED)

{

  return _hb_ot_metrics_get_position_common (font, HB_OT_METRICS_TAG_VERTICAL_ASCENDER, &metrics->ascender) &&

   _hb_ot_metrics_get_position_common (font, HB_OT_METRICS_TAG_VERTICAL_DESCENDER, &metrics->descender) &&

   _hb_ot_metrics_get_position_common (font, HB_OT_METRICS_TAG_VERTICAL_LINE_GAP, &metrics->line_gap);

}

#endif

#ifndef HB_NO_DRAW

static void

hb_ot_draw_glyph (hb_font_t *font,

      void *font_data HB_UNUSED,

      hb_codepoint_t glyph,

      hb_draw_funcs_t *draw_funcs, void *draw_data,

      void *user_data)

{

  bool embolden = font->x_strength || font->y_strength;

  hb_outline_t outline;

  { // Need draw_session to be destructed before emboldening.

    hb_draw_session_t draw_session (embolden ? hb_outline_recording_pen_get_funcs () : draw_funcs,

            embolden ? &outline : draw_data, font->slant_xy);

    if (!font->face->table.glyf->get_path (font, glyph, draw_session))

#ifndef HB_NO_CFF

    if (!font->face->table.cff1->get_path (font, glyph, draw_session))

    if (!font->face->table.cff2->get_path (font, glyph, draw_session))

#endif

    {}

  }

  if (embolden)

  {

    float x_shift = font->embolden_in_place ? 0 : (float) font->x_strength / 2;

    float y_shift = (float) font->y_strength / 2;

    if (font->x_scale < 0) x_shift = -x_shift;

    if (font->y_scale < 0) y_shift = -y_shift;

    outline.embolden (font->x_strength, font->y_strength,

          x_shift, y_shift);

    outline.replay (draw_funcs, draw_data);

  }

}

#endif

#ifndef HB_NO_PAINT

static void

hb_ot_paint_glyph (hb_font_t *font,

                   void *font_data,

                   hb_codepoint_t glyph,

                   hb_paint_funcs_t *paint_funcs, void *paint_data,

                   unsigned int palette,

                   hb_color_t foreground,

                   void *user_data)

{

#ifndef HB_NO_COLOR

  if (font->face->table.COLR->paint_glyph (font, glyph, paint_funcs, paint_data, palette, foreground)) return;

  if (font->face->table.SVG->paint_glyph (font, glyph, paint_funcs, paint_data)) return;

#ifndef HB_NO_OT_FONT_BITMAP

  if (font->face->table.CBDT->paint_glyph (font, glyph, paint_funcs, paint_data)) return;

  if (font->face->table.sbix->paint_glyph (font, glyph, paint_funcs, paint_data)) return;

#endif

#endif

  if (font->face->table.glyf->paint_glyph (font, glyph, paint_funcs, paint_data, foreground)) return;

#ifndef HB_NO_CFF

  if (font->face->table.cff1->paint_glyph (font, glyph, paint_funcs, paint_data, foreground)) return;

  if (font->face->table.cff2->paint_glyph (font, glyph, paint_funcs, paint_data, foreground)) return;

#endif

}

#endif

static inline void free_static_ot_funcs ();

static struct hb_ot_font_funcs_lazy_loader_t : hb_font_funcs_lazy_loader_t<hb_ot_font_funcs_lazy_loader_t>

{

  static hb_font_funcs_t *create ()

  {

    hb_font_funcs_t *funcs = hb_font_funcs_create ();

    hb_font_funcs_set_nominal_glyph_func (funcs, hb_ot_get_nominal_glyph, nullptr, nullptr);

    hb_font_funcs_set_nominal_glyphs_func (funcs, hb_ot_get_nominal_glyphs, nullptr, nullptr);

    hb_font_funcs_set_variation_glyph_func (funcs, hb_ot_get_variation_glyph, nullptr, nullptr);

    hb_font_funcs_set_font_h_extents_func (funcs, hb_ot_get_font_h_extents, nullptr, nullptr);

    hb_font_funcs_set_glyph_h_advances_func (funcs, hb_ot_get_glyph_h_advances, nullptr, nullptr);

    //hb_font_funcs_set_glyph_h_origin_func (funcs, hb_ot_get_glyph_h_origin, nullptr, nullptr);

#ifndef HB_NO_VERTICAL

    hb_font_funcs_set_font_v_extents_func (funcs, hb_ot_get_font_v_extents, nullptr, nullptr);

    hb_font_funcs_set_glyph_v_advances_func (funcs, hb_ot_get_glyph_v_advances, nullptr, nullptr);

    hb_font_funcs_set_glyph_v_origin_func (funcs, hb_ot_get_glyph_v_origin, nullptr, nullptr);

#endif

#ifndef HB_NO_DRAW

    hb_font_funcs_set_draw_glyph_func (funcs, hb_ot_draw_glyph, nullptr, nullptr);

#endif

#ifndef HB_NO_PAINT

    hb_font_funcs_set_paint_glyph_func (funcs, hb_ot_paint_glyph, nullptr, nullptr);

#endif

    hb_font_funcs_set_glyph_extents_func (funcs, hb_ot_get_glyph_extents, nullptr, nullptr);

    //hb_font_funcs_set_glyph_contour_point_func (funcs, hb_ot_get_glyph_contour_point, nullptr, nullptr);

#ifndef HB_NO_OT_FONT_GLYPH_NAMES

    hb_font_funcs_set_glyph_name_func (funcs, hb_ot_get_glyph_name, nullptr, nullptr);

    hb_font_funcs_set_glyph_from_name_func (funcs, hb_ot_get_glyph_from_name, nullptr, nullptr);

#endif

    hb_font_funcs_make_immutable (funcs);

    hb_atexit (free_static_ot_funcs);

    return funcs;

  }

} static_ot_funcs;

static inline

void free_static_ot_funcs ()

{

  static_ot_funcs.free_instance ();

}

static hb_font_funcs_t *

_hb_ot_get_font_funcs ()

{

  return static_ot_funcs.get_unconst ();

}

/**

 * hb_ot_font_set_funcs:

 * @font: #hb_font_t to work upon

 *

 * Sets the font functions to use when working with @font. 

 *

 * Since: 0.9.28

 **/

void

hb_ot_font_set_funcs (hb_font_t *font)

{

  hb_ot_font_t *ot_font = _hb_ot_font_create (font);

  if (unlikely (!ot_font))

    return;

  hb_font_set_funcs (font,

         _hb_ot_get_font_funcs (),

         ot_font,

         _hb_ot_font_destroy);

}

#endif