/* SPDX-License-Identifier: LGPL-2.1-or-later OR (GPL-2.0-or-later WITH eCos-exception-2.0) */

/*

  This file is part of GNU libmicrohttpd.

  Copyright (C) 2024 Evgeny Grin (Karlson2k)

  GNU libmicrohttpd is free software; you can redistribute it and/or

  modify it under the terms of the GNU Lesser General Public

  License as published by the Free Software Foundation; either

  version 2.1 of the License, or (at your option) any later version.

  GNU libmicrohttpd is distributed in the hope that it will be useful,

  but WITHOUT ANY WARRANTY; without even the implied warranty of

  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

  Lesser General Public License for more details.

  Alternatively, you can redistribute GNU libmicrohttpd and/or

  modify it under the terms of the GNU General Public License as

  published by the Free Software Foundation; either version 2 of

  the License, or (at your option) any later version, together

  with the eCos exception, as follows:

    As a special exception, if other files instantiate templates or

    use macros or inline functions from this file, or you compile this

    file and link it with other works to produce a work based on this

    file, this file does not by itself cause the resulting work to be

    covered by the GNU General Public License. However the source code

    for this file must still be made available in accordance with

    section (3) of the GNU General Public License v2.

    This exception does not invalidate any other reasons why a work

    based on this file might be covered by the GNU General Public

    License.

  You should have received copies of the GNU Lesser General Public

  License and the GNU General Public License along with this library;

  if not, see <https://www.gnu.org/licenses/>.

*/

/**

 * @file src/mhd2/response_funcs.c

 * @brief  The definition of the internal response helper functions

 * @author Karlson2k (Evgeny Grin)

 */

#include "mhd_sys_options.h"

#include "sys_malloc.h"

#include "mhd_assert.h"

#include "sys_null_macro.h"

#include "mhd_response.h"

#include "response_funcs.h"

#include "mhd_locks.h"

#include "response_options.h"

#include "mhd_atomic_counter.h"

MHD_INTERNAL

MHD_FN_PAR_NONNULL_ALL_ bool

response_make_reusable (struct MHD_Response *restrict r)

{

  mhd_assert (! r->reuse.reusable);

  mhd_assert (! r->frozen);

  mhd_assert (NULL != r->settings);

  if (mhd_mutex_init (&(r->reuse.settings_lock)))

  {

    if (mhd_atomic_counter_init (&(r->reuse.counter), 1))

    {

      r->reuse.reusable = true;

      return true;

    }

    (void) mhd_mutex_destroy (&(r->reuse.settings_lock));

  }

  return false;

}

MHD_INTERNAL

MHD_FN_PAR_NONNULL_ALL_ void

mhd_response_deinit_reusable (struct MHD_Response *restrict r)

{

  mhd_assert (r->reuse.reusable);

  mhd_assert (0 == mhd_atomic_counter_get (&(r->reuse.counter)));

  mhd_atomic_counter_deinit (&(r->reuse.counter));

  mhd_mutex_destroy_chk (&(r->reuse.settings_lock));

}

static MHD_FN_PAR_NONNULL_ALL_ void

response_set_properties (struct MHD_Response *restrict r)

{

  struct ResponseOptions *restrict const s = r->settings;

  mhd_assert (NULL != s);

  r->cfg.head_only = s->head_only_response;

  if (s->http_1_0_compatible_strict)

  {

    r->cfg.close_forced = true;

    r->cfg.chunked = false;

    r->cfg.mode_1_0 = s->http_1_0_server;

  }

  else if (s->http_1_0_server)

  {

    r->cfg.close_forced = s->conn_close || (MHD_SIZE_UNKNOWN == r->cntn_size);

    r->cfg.chunked = false;

    r->cfg.mode_1_0 = true;

  }

  else

  {

    r->cfg.close_forced = s->conn_close;

    r->cfg.chunked = s->chunked_enc || (MHD_SIZE_UNKNOWN == r->cntn_size);

    r->cfg.mode_1_0 = false;

  }

  r->cfg.cnt_len_by_app = s->insanity_header_content_length; // TODO: set only if "content-lengh" header is used

  // TODO: calculate size of the headers and the "Connection:" header

  r->frozen = true;

  r->settings = NULL;

  free (s);

}

MHD_INTERNAL MHD_FN_PAR_NONNULL_ALL_ void

mhd_response_check_frozen_freeze (struct MHD_Response *restrict response)

{

  bool need_unlock;

  if (response->frozen)

    return;

  if (response->reuse.reusable)

  {

    mhd_mutex_lock_chk (&(response->reuse.settings_lock));

    need_unlock = true;

  }

  else

    need_unlock = false;

  if (! response->frozen)/* Re-check under the lock */

  {

    mhd_assert ((! response->reuse.reusable) || \

                (1 == mhd_atomic_counter_get (&(response->reuse.counter))));

    response_set_properties (response);

  }

  if (need_unlock)

    mhd_mutex_unlock_chk (&(response->reuse.settings_lock));

}