/*

 * Copyright © 2012  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

 */

#include "hb.hh"

#include "hb-shaper.hh"

#include "hb-machinery.hh"

static const hb_shaper_entry_t _hb_all_shapers[] = {

#define HB_SHAPER_IMPLEMENT(name) {#name, _hb_##name##_shape},

#include "hb-shaper-list.hh"

#undef HB_SHAPER_IMPLEMENT

};

#ifndef HB_NO_SHAPER

static_assert (0 != ARRAY_LENGTH_CONST (_hb_all_shapers), "No shaper enabled.");

#endif

static inline void free_static_shapers ();

static struct hb_shapers_lazy_loader_t : hb_lazy_loader_t<hb_shaper_entry_t,

                hb_shapers_lazy_loader_t>

{

  static hb_shaper_entry_t *create ()

  {

    char *env = getenv ("HB_SHAPER_LIST");

    if (!env || !*env)

      return nullptr;

    hb_shaper_entry_t *shapers = (hb_shaper_entry_t *) hb_calloc (1, sizeof (_hb_all_shapers));

    if (unlikely (!shapers))

      return nullptr;

    hb_memcpy (shapers, _hb_all_shapers, sizeof (_hb_all_shapers));

     /* Reorder shaper list to prefer requested shapers. */

    unsigned int i = 0;

    char *end, *p = env;

    for (;;)

    {

      end = strchr (p, ',');

      if (!end)

  end = p + strlen (p);

      for (unsigned int j = i; j < ARRAY_LENGTH_CONST (_hb_all_shapers); j++)

  if (end - p == (int) strlen (shapers[j].name) &&

      0 == strncmp (shapers[j].name, p, end - p))

  {

    /* Reorder this shaper to position i */

   struct hb_shaper_entry_t t = shapers[j];

   memmove (&shapers[i + 1], &shapers[i], sizeof (shapers[i]) * (j - i));

   shapers[i] = t;

   i++;

  }

      if (!*end)

  break;

      else

  p = end + 1;

    }

    hb_atexit (free_static_shapers);

    return shapers;

  }

  static void destroy (hb_shaper_entry_t *p) { hb_free (p); }

  static const hb_shaper_entry_t *get_null ()      { return _hb_all_shapers; }

} static_shapers;

static inline

void free_static_shapers ()

{

  static_shapers.free_instance ();

}

const hb_shaper_entry_t *

_hb_shapers_get ()

{

  return static_shapers.get_unconst ();

}