/*-
 * Copyright (c)2003 Citrus Project,
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include "dcmtk/config/osconfig.h"
#include "citrus_stdenc.h"

#include <errno.h>
#include <stdlib.h>
#include <string.h>

#include "citrus_bcs.h"
#include "citrus_types.h"
#include "citrus_module.h"
#include "citrus_none.h"

#ifdef _MSC_VER
/* disable warning about typecasts from void * to function pointer in older MSVC versions */
#pragma warning(disable: 4055)
#endif

struct _citrus_stdenc _citrus_stdenc_default = {
    &_citrus_NONE_stdenc_ops,   /* ce_ops */
    NULL,               /* ce_closure */
    NULL,               /* ce_module */
    &_citrus_NONE_stdenc_traits,    /* ce_traits */
};

int
_citrus_stdenc_open(struct _citrus_stdenc * * rce,
    char const * encname, const void * variable,
    size_t lenvar)
{
    struct _citrus_stdenc *ce;
    _citrus_module_t handle;
    _citrus_stdenc_getops_t getops;
    int ret;

    if (!strcmp(encname, _CITRUS_DEFAULT_STDENC_NAME)) {
        *rce = &_citrus_stdenc_default;
        return (0);
    }
    ce = malloc(sizeof(*ce));
    if (ce == NULL) {
        ret = errno;
        goto bad;
    }
    ce->ce_ops = NULL;
    ce->ce_closure = NULL;
    ce->ce_module = NULL;
    ce->ce_traits = NULL;

    ret = _citrus_load_module(&handle, encname);
    if (ret)
        goto bad;

    ce->ce_module = handle;

    getops = (_citrus_stdenc_getops_t)_citrus_find_getops(ce->ce_module,
        encname, "stdenc");
    if (getops == NULL) {
        ret = EINVAL;
        goto bad;
    }

    ce->ce_ops = (struct _citrus_stdenc_ops *)malloc(sizeof(*ce->ce_ops));
    if (ce->ce_ops == NULL) {
        ret = errno;
        goto bad;
    }

    ret = (*getops)(ce->ce_ops, sizeof(*ce->ce_ops));
    if (ret)
        goto bad;

    /* validation check */
    if (ce->ce_ops->eo_init == NULL ||
        ce->ce_ops->eo_uninit == NULL ||
        ce->ce_ops->eo_init_state == NULL ||
        ce->ce_ops->eo_mbtocs == NULL ||
        ce->ce_ops->eo_cstomb == NULL ||
        ce->ce_ops->eo_mbtowc == NULL ||
        ce->ce_ops->eo_wctomb == NULL ||
        ce->ce_ops->eo_get_state_desc == NULL) {
            ret = EINVAL;
            goto bad;
    }

    /* allocate traits */
    ce->ce_traits = malloc(sizeof(*ce->ce_traits));
    if (ce->ce_traits == NULL) {
        ret = errno;
        goto bad;
    }
    /* init and get closure */
    ret = (*ce->ce_ops->eo_init)(ce, variable, lenvar, ce->ce_traits);
    if (ret)
        goto bad;

    *rce = ce;

    return (0);

bad:
    _citrus_stdenc_close(ce);
    return (ret);
}

void
_citrus_stdenc_close(struct _citrus_stdenc *ce)
{

    if (ce == &_citrus_stdenc_default)
        return;

    if (ce->ce_module) {
        if (ce->ce_ops) {
            if (ce->ce_closure && ce->ce_ops->eo_uninit)
                (*ce->ce_ops->eo_uninit)(ce);
            free(ce->ce_ops);
        }
        free(ce->ce_traits);
        _citrus_unload_module(ce->ce_module);
    }
    free(ce);
}