/* Licensed to the Apache Software Foundation (ASF) under one or more

 * contributor license agreements.  See the NOTICE file distributed with

 * this work for additional information regarding copyright ownership.

 * The ASF licenses this file to You under the Apache License, Version 2.0

 * (the "License"); you may not use this file except in compliance with

 * the License.  You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

#include "apu.h"

#include "apr_private.h"

#include "apr_lib.h"

#include "apr_strings.h"

#include "apr_portable.h"

#include "apr_xlate.h"

/* If no implementation is available, don't generate code here since

 * apr_xlate.h emitted macros which return APR_ENOTIMPL.

 */

#if APR_HAS_XLATE

#ifdef HAVE_STDDEF_H

#include <stddef.h> /* for NULL */

#endif

#if APR_HAVE_STRING_H

#include <string.h>

#endif

#if APR_HAVE_STRINGS_H

#include <strings.h>

#endif

#ifdef HAVE_ICONV_H

#include <iconv.h>

#endif

#if defined(APU_ICONV_INBUF_CONST)

#define ICONV_INBUF_TYPE const char **

#else

#define ICONV_INBUF_TYPE char **

#endif

#ifndef min

#define min(x,y) ((x) <= (y) ? (x) : (y))

#endif

struct apr_xlate_t {

    apr_pool_t *pool;

    char *frompage;

    char *topage;

    char *sbcs_table;

#if APU_HAVE_ICONV

    iconv_t ich;

#endif

};

static const char *handle_special_names(const char *page, apr_pool_t *pool)

{

    if (page == APR_DEFAULT_CHARSET) {

        return apr_os_default_encoding(pool);

    }

    else if (page == APR_LOCALE_CHARSET) {

        return apr_os_locale_encoding(pool);

    }

#ifdef __MVS__

    else if (!strcasecmp(page, "ISO-8859-1")) {

        return "ISO8859-1"; /* z/OS ASCII name has no dash after ISO */

    }

#endif

    else {

        return page;

    }

}

static apr_status_t apr_xlate_cleanup(void *convset)

{

    apr_xlate_t *old = convset;

#if APU_HAVE_ICONV

    if (old->ich != (iconv_t)-1) {

        if (iconv_close(old->ich)) {

            int rv = errno;

            /* Sometimes, iconv is not good about setting errno. */

            return rv ? rv : APR_EINVAL;

        }

    }

#endif

    return APR_SUCCESS;

}

#if APU_HAVE_ICONV

static void check_sbcs(apr_xlate_t *convset)

{

    char inbuf[256], outbuf[256];

    char *inbufptr = inbuf;

    char *outbufptr = outbuf;

    apr_size_t inbytes_left, outbytes_left;

    int i;

    apr_size_t translated;

    for (i = 0; i < sizeof(inbuf); i++) {

        inbuf[i] = i;

    }

    inbytes_left = outbytes_left = sizeof(inbuf);

    translated = iconv(convset->ich, (ICONV_INBUF_TYPE)&inbufptr,

                       &inbytes_left, &outbufptr, &outbytes_left);

    if (translated != (apr_size_t)-1

        && inbytes_left == 0

        && outbytes_left == 0) {

        /* hurray... this is simple translation; save the table,

         * close the iconv descriptor

         */

        convset->sbcs_table = apr_pmemdup(convset->pool, outbuf, sizeof(outbuf));

        iconv_close(convset->ich);

        convset->ich = (iconv_t)-1;

        /* TODO: add the table to the cache */

    }

    else {

        /* reset the iconv descriptor, since it's now in an undefined

         * state. */

        iconv_close(convset->ich);

        convset->ich = iconv_open(convset->topage, convset->frompage);

    }

}

#elif APU_HAVE_APR_ICONV

static void check_sbcs(apr_xlate_t *convset)

{

    char inbuf[256], outbuf[256];

    char *inbufptr = inbuf;

    char *outbufptr = outbuf;

    apr_size_t inbytes_left, outbytes_left;

    int i;

    apr_size_t translated;

    apr_status_t rv;

    for (i = 0; i < sizeof(inbuf); i++) {

        inbuf[i] = i;

    }

    inbytes_left = outbytes_left = sizeof(inbuf);

    rv = apr_iconv(convset->ich, (ICONV_INBUF_TYPE)&inbufptr,

                   &inbytes_left, &outbufptr, &outbytes_left,

                   &translated);

    if ((rv == APR_SUCCESS)

        && (translated != (apr_size_t)-1)

        && inbytes_left == 0

        && outbytes_left == 0) {

        /* hurray... this is simple translation; save the table,

         * close the iconv descriptor

         */

        convset->sbcs_table = apr_palloc(convset->pool, sizeof(outbuf));

        memcpy(convset->sbcs_table, outbuf, sizeof(outbuf));

        apr_iconv_close(convset->ich, convset->pool);

        convset->ich = (apr_iconv_t)-1;

        /* TODO: add the table to the cache */

    }

    else {

        /* reset the iconv descriptor, since it's now in an undefined

         * state. */

        apr_iconv_close(convset->ich, convset->pool);

        rv = apr_iconv_open(convset->topage, convset->frompage,

                            convset->pool, &convset->ich);

    }

}

#endif /* APU_HAVE_APR_ICONV */

static void make_identity_table(apr_xlate_t *convset)

{

  int i;

  convset->sbcs_table = apr_palloc(convset->pool, 256);

  for (i = 0; i < 256; i++)

      convset->sbcs_table[i] = i;

}

APR_DECLARE(apr_status_t) apr_xlate_open(apr_xlate_t **convset,

                                         const char *topage,

                                         const char *frompage,

                                         apr_pool_t *pool)

{

    apr_status_t rv;

    apr_xlate_t *new;

    int found = 0;

    *convset = NULL;

    topage = handle_special_names(topage, pool);

    frompage = handle_special_names(frompage, pool);

    new = (apr_xlate_t *)apr_pcalloc(pool, sizeof(apr_xlate_t));

    if (!new) {

        return APR_ENOMEM;

    }

    new->pool = pool;

    new->topage = apr_pstrdup(pool, topage);

    new->frompage = apr_pstrdup(pool, frompage);

    if (!new->topage || !new->frompage) {

        return APR_ENOMEM;

    }

#ifdef TODO

    /* search cache of codepage pairs; we may be able to avoid the

     * expensive iconv_open()

     */

    set found to non-zero if found in the cache

#endif

    if ((! found) && (strcmp(topage, frompage) == 0)) {

        /* to and from are the same */

        found = 1;

        make_identity_table(new);

    }

#if APU_HAVE_APR_ICONV

    if (!found) {

        rv = apr_iconv_open(topage, frompage, pool, &new->ich);

        if (rv != APR_SUCCESS) {

            return rv;

        }

        found = 1;

        check_sbcs(new);

    } else

        new->ich = (apr_iconv_t)-1;

#elif APU_HAVE_ICONV

    if (!found) {

        new->ich = iconv_open(topage, frompage);

        if (new->ich == (iconv_t)-1) {

            int rv = errno;

            /* Sometimes, iconv is not good about setting errno. */

            return rv ? rv : APR_EINVAL;

        }

        found = 1;

        check_sbcs(new);

    } else

        new->ich = (iconv_t)-1;

#endif /* APU_HAVE_ICONV */

    if (found) {

        *convset = new;

        apr_pool_cleanup_register(pool, (void *)new, apr_xlate_cleanup,

                            apr_pool_cleanup_null);

        rv = APR_SUCCESS;

    }

    else {

        rv = APR_EINVAL; /* iconv() would return EINVAL if it

                                couldn't handle the pair */

    }

    return rv;

}

APR_DECLARE(apr_status_t) apr_xlate_sb_get(apr_xlate_t *convset, int *onoff)

{

    *onoff = convset->sbcs_table != NULL;

    return APR_SUCCESS;

}

APR_DECLARE(apr_status_t) apr_xlate_conv_buffer(apr_xlate_t *convset,

                                                const char *inbuf,

                                                apr_size_t *inbytes_left,

                                                char *outbuf,

                                                apr_size_t *outbytes_left)

{

    apr_status_t status = APR_SUCCESS;

#if APU_HAVE_ICONV

    if (convset->ich != (iconv_t)-1) {

        const char *inbufptr = inbuf;

        char *outbufptr = outbuf;

        apr_size_t translated;

        translated = iconv(convset->ich, (ICONV_INBUF_TYPE)&inbufptr,

                           inbytes_left, &outbufptr, outbytes_left);

        /* If everything went fine but we ran out of buffer, don't

         * report it as an error.  Caller needs to look at the two

         * bytes-left values anyway.

         *

         * There are three expected cases where rc is -1.  In each of

         * these cases, *inbytes_left != 0.

         * a) the non-error condition where we ran out of output

         *    buffer

         * b) the non-error condition where we ran out of input (i.e.,

         *    the last input character is incomplete)

         * c) the error condition where the input is invalid

         */

        if (translated == (apr_size_t)-1) {

            int rv = errno;

            switch (rv) {

            case E2BIG:  /* out of space on output */

                status = 0; /* change table lookup code below if you

                               make this an error */

                break;

            case EINVAL: /* input character not complete (yet) */

                status = APR_INCOMPLETE;

                break;

            case EILSEQ: /* bad input byte */

                status = APR_EINVAL;

                break;

             /* Sometimes, iconv is not good about setting errno. */

            case 0:

                status = APR_INCOMPLETE;

                break;

            default:

                status = rv;

                break;

            }

        }

    }

    else

#endif

    if (inbuf) {

        apr_size_t to_convert = min(*inbytes_left, *outbytes_left);

        apr_size_t converted = to_convert;

        char *table = convset->sbcs_table;

        while (to_convert) {

            *outbuf = table[(unsigned char)*inbuf];

            ++outbuf;

            ++inbuf;

            --to_convert;

        }

        *inbytes_left -= converted;

        *outbytes_left -= converted;

    }

    return status;

}

APR_DECLARE(apr_int32_t) apr_xlate_conv_byte(apr_xlate_t *convset,

                                             unsigned char inchar)

{

    if (convset->sbcs_table) {

        return convset->sbcs_table[inchar];

    }

    else {

        return -1;

    }

}

APR_DECLARE(apr_status_t) apr_xlate_close(apr_xlate_t *convset)

{

    return apr_pool_cleanup_run(convset->pool, convset, apr_xlate_cleanup);

}

#else /* !APR_HAS_XLATE */

APR_DECLARE(apr_status_t) apr_xlate_open(apr_xlate_t **convset,

                                         const char *topage,

                                         const char *frompage,

                                         apr_pool_t *pool)

{

    return APR_ENOTIMPL;

}

APR_DECLARE(apr_status_t) apr_xlate_sb_get(apr_xlate_t *convset, int *onoff)

{

    return APR_ENOTIMPL;

}

APR_DECLARE(apr_int32_t) apr_xlate_conv_byte(apr_xlate_t *convset,

                                             unsigned char inchar)

{

    return (-1);

}

APR_DECLARE(apr_status_t) apr_xlate_conv_buffer(apr_xlate_t *convset,

                                                const char *inbuf,

                                                apr_size_t *inbytes_left,

                                                char *outbuf,

                                                apr_size_t *outbytes_left)

{

    return APR_ENOTIMPL;

}

APR_DECLARE(apr_status_t) apr_xlate_close(apr_xlate_t *convset)

{

    return APR_ENOTIMPL;

}

#endif /* APR_HAS_XLATE */