/*      $NetBSD: rune.c,v 1.50 2025/09/15 00:11:54 riastradh Exp $      */
/*-
 * Copyright (c)2010 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 <sys/endian.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <assert.h>
#include <errno.h>
#include <fcntl.h>
#define __SETLOCALE_SOURCE__
#include <locale.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <wchar.h>

#include "ctype_guard.h"

#include "setlocale_local.h"

#include "citrus_module.h"
#include "citrus_ctype.h"

#include "runetype_local.h"

#include "multibyte.h"

#include "_wctype_local.h"
#include "_wctrans_local.h"

typedef struct {
        _RuneLocale rl;
#ifdef __CHAR_UNSIGNED__
        unsigned short  rlp_ctype_tab  [_CTYPE_NUM_CHARS + 1];
        short           rlp_tolower_tab[_CTYPE_NUM_CHARS + 1];
        short           rlp_toupper_tab[_CTYPE_NUM_CHARS + 1];
#else
        unsigned short  *rlp_ctype_tab;
        short           *rlp_tolower_tab;
        short           *rlp_toupper_tab;
#endif
        char            rlp_codeset[33]; /* XXX */

#ifdef __BUILD_LEGACY
        unsigned char   rlp_compat_bsdctype[_CTYPE_NUM_CHARS + 1];
#endif
} _RuneLocalePriv;

#ifndef __CHAR_UNSIGNED__

#define roundup(X, N)   ((((X) + ((N) - 1))/(N))*(N))

static void *
alloc_guarded(size_t elemsize, size_t nelem)
{
        const unsigned long page_size = sysconf(_SC_PAGESIZE);
        size_t nbytes = 0;
        void *p = MAP_FAILED, *q = NULL;

        _DIAGASSERT(elemsize != 0);
        if (nelem > SIZE_MAX/elemsize)
                goto fail;
        nbytes = page_size + roundup(elemsize*nelem, page_size);
        p = mmap(NULL, nbytes, PROT_READ|PROT_WRITE, MAP_ANON,
            /*fd*/-1, /*offset*/0);
        if (p == MAP_FAILED)
                goto fail;
        if (allow_ctype_abuse())
                memset(p, 0xff, page_size);
        else if (mprotect(p, page_size, PROT_NONE) == -1)
                goto fail;
        q = (char *)p + page_size;
        return q;

fail:   if (p != MAP_FAILED)
                (void)munmap(p, nbytes);
        return NULL;
}

static void
free_guarded(void *q, size_t elemsize, size_t nelem)
{
        const unsigned long page_size = sysconf(_SC_PAGESIZE);
        size_t nbytes = 0;
        void *p;

        if (q == NULL)
                return;
        _DIAGASSERT(elemsize <= SIZE_MAX/nelem);
        nbytes = page_size + roundup(elemsize*nelem, page_size);
        p = (char *)q - page_size;
        (void)munmap(p, nbytes);
}

#endif  /* !__CHAR_UNSIGNED__ */

static __inline void
_rune_wctype_init(_RuneLocale *rl)
{
        memcpy(&rl->rl_wctype, &_DefaultRuneLocale.rl_wctype,
            sizeof(rl->rl_wctype));
}

static __inline void
_rune_wctrans_init(_RuneLocale *rl)
{
        rl->rl_wctrans[_WCTRANS_INDEX_LOWER].te_name   = "tolower";
        rl->rl_wctrans[_WCTRANS_INDEX_LOWER].te_cached = &rl->rl_maplower[0];
        rl->rl_wctrans[_WCTRANS_INDEX_LOWER].te_extmap = &rl->rl_maplower_ext;
        rl->rl_wctrans[_WCTRANS_INDEX_UPPER].te_name   = "toupper";
        rl->rl_wctrans[_WCTRANS_INDEX_UPPER].te_cached = &rl->rl_mapupper[0];
        rl->rl_wctrans[_WCTRANS_INDEX_UPPER].te_extmap = &rl->rl_mapupper_ext;
}

static __inline void
_rune_init_priv(_RuneLocalePriv *rlp)
{
#if _CTYPE_CACHE_SIZE != _CTYPE_NUM_CHARS
        int i;

        for (i = _CTYPE_CACHE_SIZE; i < _CTYPE_NUM_CHARS; ++i) {
                rlp->rlp_ctype_tab  [i + 1] = 0;
                rlp->rlp_tolower_tab[i + 1] = i;
                rlp->rlp_toupper_tab[i + 1] = i;

#ifdef __BUILD_LEGACY
                rlp->rlp_compat_bsdctype[i + 1] = 0;
#endif
        }
#endif
        rlp->rlp_ctype_tab  [0] = 0;
        rlp->rlp_tolower_tab[0] = EOF;
        rlp->rlp_toupper_tab[0] = EOF;

        rlp->rl.rl_ctype_tab   = (const unsigned short *)&rlp->rlp_ctype_tab[0];
        rlp->rl.rl_tolower_tab = (const short *)&rlp->rlp_tolower_tab[0];
        rlp->rl.rl_toupper_tab = (const short *)&rlp->rlp_toupper_tab[0];
        rlp->rl.rl_codeset     = (const char *)&rlp->rlp_codeset[0];

        _rune_wctype_init(&rlp->rl);
        _rune_wctrans_init(&rlp->rl);

#ifdef __BUILD_LEGACY
        rlp->rlp_compat_bsdctype[0] = 0;
        rlp->rl.rl_compat_bsdctype = (const unsigned char *)
            &rlp->rlp_compat_bsdctype[0];
#endif
}

static __inline void
_rune_find_codeset(char *s, size_t n,
    char *var, size_t *plenvar)
{
        size_t lenvar;
        const char *endvar;

#define _RUNE_CODESET_LEN (sizeof(_RUNE_CODESET)-1)

        lenvar = *plenvar;
        for (/**/; lenvar > _RUNE_CODESET_LEN; ++var, --lenvar) {
                if (!memcmp(var, _RUNE_CODESET, _RUNE_CODESET_LEN)) {
                        *var = '\0';
                        *plenvar -= lenvar;
                        endvar = &var[_RUNE_CODESET_LEN];
                        while (n-- > 1 && lenvar-- > _RUNE_CODESET_LEN) {
                                if (*endvar == ' ' || *endvar == '\t')
                                        break;
                                *s++ = *endvar++;
                        }
                        break;
                }
        }
        *s = '\0';
}

#ifdef __BUILD_LEGACY
static __inline int
_runetype_to_bsdctype(_RuneType bits)
{
        int ret;

        if (bits == (_RuneType)0)
                return 0;
        ret = 0;
        if (bits & _RUNETYPE_U)
                ret |= _COMPAT_U;
        if (bits & _RUNETYPE_L)
                ret |= _COMPAT_L;
        if (bits & _RUNETYPE_D)
                ret |= _COMPAT_N;
        if (bits & _RUNETYPE_S)
                ret |= _COMPAT_S;
        if (bits & _RUNETYPE_P)
                ret |= _COMPAT_P;
        if (bits & _RUNETYPE_C)
                ret |= _COMPAT_C;
        if ((bits & (_RUNETYPE_X | _RUNETYPE_D)) == _RUNETYPE_X)
                ret |= _COMPAT_X;
        if ((bits & (_RUNETYPE_R | _RUNETYPE_G)) == _RUNETYPE_R)
                ret |= _COMPAT_B;
        return ret;
}
#endif /* __BUILD_LEGACY */

static __inline int
_rune_read_file(const char * __restrict var, size_t lenvar,
    _RuneLocale ** __restrict prl)
{
        int ret, i;
        const _FileRuneLocale *frl;
        const _FileRuneEntry *fre;
        const uint32_t *frune;
        _RuneLocalePriv *rlp;
        _RuneLocale *rl;
        _RuneEntry *re;
        uint32_t *rune;
        uint32_t runetype_len, maplower_len, mapupper_len, variable_len;
        size_t len, n;

        if (lenvar < sizeof(*frl))
                return EFTYPE;
        lenvar -= sizeof(*frl);
        frl = (const _FileRuneLocale *)(const void *)var;
        if (memcmp(_RUNECT10_MAGIC, &frl->frl_magic[0], sizeof(frl->frl_magic)))
                return EFTYPE;

        runetype_len = be32toh(frl->frl_runetype_ext.frr_nranges);
        maplower_len = be32toh(frl->frl_maplower_ext.frr_nranges);
        mapupper_len = be32toh(frl->frl_mapupper_ext.frr_nranges);
        len = runetype_len + maplower_len + mapupper_len;

        fre = (const _FileRuneEntry *)(const void *)(frl + 1);
        frune = (const uint32_t *)(const void *)(fre + len);

        variable_len = be32toh((uint32_t)frl->frl_variable_len);

        n = len * sizeof(*fre);
        if (lenvar < n)
                return EFTYPE;
        lenvar -= n;

        n = sizeof(*rlp) + (len * sizeof(*re)) + lenvar;
        rlp = (_RuneLocalePriv *)malloc(n);
        if (rlp == NULL)
                return ENOMEM;
#ifndef __CHAR_UNSIGNED__
        rlp->rlp_ctype_tab = NULL;
        rlp->rlp_tolower_tab = NULL;
        rlp->rlp_toupper_tab = NULL;
        if ((rlp->rlp_ctype_tab = alloc_guarded(sizeof(rlp->rlp_ctype_tab[0]),
                    _CTYPE_NUM_CHARS + 1)) == NULL ||
            (rlp->rlp_tolower_tab =
                alloc_guarded(sizeof(rlp->rlp_tolower_tab[0]),
                    _CTYPE_NUM_CHARS + 1)) == NULL ||
            (rlp->rlp_toupper_tab =
                alloc_guarded(sizeof(rlp->rlp_toupper_tab[0]),
                    _CTYPE_NUM_CHARS + 1)) == NULL) {
                ret = ENOMEM;
                goto err;
        }
#endif  /* !__CHAR_UNSIGNED__ */
        _rune_init_priv(rlp);

        rl = &rlp->rl;
        re = (_RuneEntry *)(void *)(rlp + 1);
        rune = (uint32_t *)(void *)(re + len);

        for (i = 0; i < _CTYPE_CACHE_SIZE; ++i) {
                rl->rl_runetype[i] = be32toh(frl->frl_runetype[i]);
                rl->rl_maplower[i] = be32toh((uint32_t)frl->frl_maplower[i]);
                rl->rl_mapupper[i] = be32toh((uint32_t)frl->frl_mapupper[i]);
        }

#define READ_RANGE(name)                                                \
do {                                                                    \
        const _FileRuneEntry *end_fre;                                  \
        const uint32_t *end_frune;                                      \
                                                                        \
        rl->rl_##name##_ext.rr_nranges = name##_len;                    \
        rl->rl_##name##_ext.rr_rune_ranges = re;                        \
                                                                        \
        end_fre = fre + name##_len;                                     \
        while (fre < end_fre) {                                         \
                re->re_min = be32toh((uint32_t)fre->fre_min);           \
                re->re_max = be32toh((uint32_t)fre->fre_max);           \
                re->re_map = be32toh((uint32_t)fre->fre_map);           \
                if (re->re_map != 0) {                                  \
                        re->re_rune_types = NULL;                       \
                } else {                                                \
                        re->re_rune_types = rune;                       \
                        len = re->re_max - re->re_min + 1;              \
                        n = len * sizeof(*frune);                       \
                        if (lenvar < n) {                               \
                                ret = EFTYPE;                           \
                                goto err;                               \
                        }                                               \
                        lenvar -= n;                                    \
                        end_frune = frune + len;                        \
                        while (frune < end_frune)                       \
                                *rune++ = be32toh(*frune++);            \
                }                                                       \
                ++fre, ++re;                                            \
        }                                                               \
} while (0)

        READ_RANGE(runetype);
        READ_RANGE(maplower);
        READ_RANGE(mapupper);

        if (lenvar < variable_len) {
                ret = EFTYPE;
                goto err;
        }

        memcpy((void *)rune, (void const *)frune, variable_len);
        rl->rl_variable_len = variable_len;
        rl->rl_variable = (void *)rune;

        _rune_find_codeset(rlp->rlp_codeset, sizeof(rlp->rlp_codeset),
            (char *)rl->rl_variable, &rl->rl_variable_len);

        ret = _citrus_ctype_open(&rl->rl_citrus_ctype, frl->frl_encoding,
            rl->rl_variable, rl->rl_variable_len, _PRIVSIZE);
        if (ret)
                goto err;
        if (__mb_len_max_runtime <
            _citrus_ctype_get_mb_cur_max(rl->rl_citrus_ctype)) {
                ret = EINVAL;
                goto err;
        }

        for (i = 0; i < _CTYPE_CACHE_SIZE; ++i) {
                wint_t wc;
                _RuneType rc;

                ret = _citrus_ctype_btowc(rl->rl_citrus_ctype, i, &wc);
                if (ret)
                        goto err;
                if (wc == WEOF) {
                        rlp->rlp_ctype_tab[i + 1] = 0;
                        rlp->rlp_tolower_tab[i + 1] = i;
                        rlp->rlp_toupper_tab[i + 1] = i;
                } else {
                        rc = _runetype_priv(rl, wc);
                        rlp->rlp_ctype_tab[i + 1] = (unsigned short)
                            ((rc & ~_RUNETYPE_SWM) >> 8);

#ifdef __BUILD_LEGACY
                        rlp->rlp_compat_bsdctype[i + 1]
                          = _runetype_to_bsdctype(rc);
#endif

#define CONVERT_MAP(name)                                               \
do {                                                                    \
        wint_t map;                                                     \
        int c;                                                          \
                                                                        \
        map = _towctrans_priv(wc, _wctrans_##name(rl));                 \
        if (map == wc || (_citrus_ctype_wctob(rl->rl_citrus_ctype,      \
            map, &c)  || c == EOF))                                     \
                c = i;                                                  \
        rlp->rlp_to##name##_tab[i + 1] = (short)c;                      \
} while (0)

                        CONVERT_MAP(lower);
                        CONVERT_MAP(upper);
                }
        }
        *prl = rl;
        return 0;

err:
#ifndef __CHAR_UNSIGNED__
        free_guarded(rlp->rlp_ctype_tab, sizeof(rlp->rlp_ctype_tab[0]),
            _CTYPE_NUM_CHARS + 1);
        free_guarded(rlp->rlp_tolower_tab, sizeof(rlp->rlp_tolower_tab[0]),
            _CTYPE_NUM_CHARS + 1);
        free_guarded(rlp->rlp_toupper_tab, sizeof(rlp->rlp_toupper_tab[0]),
            _CTYPE_NUM_CHARS + 1);
#endif
        free(rlp);
        return ret;
}

int
_rune_load(const char * __restrict var, size_t lenvar,
    _RuneLocale ** __restrict prl)
{
        int ret;

        _DIAGASSERT(var != NULL || lenvar < 1);
        _DIAGASSERT(prl != NULL);

        if (lenvar < 1)
                return EFTYPE;
        switch (*var) {
        case 'R':
                ret = _rune_read_file(var, lenvar, prl);
                break;
        default:
                ret = EFTYPE;
        }
        return ret;
}