/*
 * Copyright 2014 Garrett D'Amore <garrett@damore.org>
 * Copyright 2010 Nexenta Systems, Inc.  All rights reserved.
 * Copyright (c) 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Paul Borman at Krystal Technologies.
 *
 * 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.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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 "lint.h"
#include "file64.h"
#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <fcntl.h>
#include <unistd.h>

#include "libc.h"
#include "runetype.h"
#include "runefile.h"

_RuneLocale *
_Read_RuneMagi(const char *fname)
{
        char *fdata, *data;
        void *lastp;
        _FileRuneLocale *frl;
        _RuneLocale *rl;
        _FileRuneEntry *frr;
        _RuneEntry *rr;
        struct stat sb;
        int x, saverr;
        void *variable;
        _FileRuneEntry *runetype_ext_ranges;
        _FileRuneEntry *maplower_ext_ranges;
        _FileRuneEntry *mapupper_ext_ranges;
        int runetype_ext_len = 0;
        int fd;

        if ((fd = open(fname, O_RDONLY)) < 0) {
                errno = EINVAL;
                return (NULL);
        }

        if (fstat(fd, &sb) < 0) {
                (void) close(fd);
                errno = EINVAL;
                return (NULL);
        }

        if ((size_t)sb.st_size < sizeof (_FileRuneLocale)) {
                (void) close(fd);
                errno = EINVAL;
                return (NULL);
        }


        fdata = mmap(NULL, sb.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
        (void) close(fd);
        if (fdata == NULL) {
                errno = EINVAL;
                return (NULL);
        }

        frl = (_FileRuneLocale *)(void *)fdata;
        lastp = fdata + sb.st_size;

        variable = frl + 1;

        if (memcmp(frl->magic, _FILE_RUNE_MAGIC_1, sizeof (frl->magic))) {
                goto invalid;
        }

        runetype_ext_ranges = (_FileRuneEntry *)variable;
        variable = runetype_ext_ranges + frl->runetype_ext_nranges;
        if (variable > lastp) {
                goto invalid;
        }

        maplower_ext_ranges = (_FileRuneEntry *)variable;
        variable = maplower_ext_ranges + frl->maplower_ext_nranges;
        if (variable > lastp) {
                goto invalid;
        }

        mapupper_ext_ranges = (_FileRuneEntry *)variable;
        variable = mapupper_ext_ranges + frl->mapupper_ext_nranges;
        if (variable > lastp) {
                goto invalid;
        }

        frr = runetype_ext_ranges;
        for (x = 0; x < frl->runetype_ext_nranges; ++x) {
                uint32_t *types;

                if (frr[x].map == 0) {
                        int len = frr[x].max - frr[x].min + 1;
                        types = variable;
                        variable = types + len;
                        runetype_ext_len += len;
                        if (variable > lastp) {
                                goto invalid;
                        }
                }
        }

        if ((char *)variable + frl->variable_len > (char *)lastp) {
                goto invalid;
        }

        /*
         * Convert from disk format to host format.
         */
        data = libc_malloc(sizeof (_RuneLocale) +
            (frl->runetype_ext_nranges + frl->maplower_ext_nranges +
            frl->mapupper_ext_nranges) * sizeof (_RuneEntry) +
            runetype_ext_len * sizeof (*rr->__types) +
            frl->variable_len);
        if (data == NULL) {
                saverr = errno;
                (void) munmap(fdata, sb.st_size);
                errno = saverr;
                return (NULL);
        }

        rl = (_RuneLocale *)(void *)data;
        rl->__variable = rl + 1;

        (void) memcpy(rl->__magic, _RUNE_MAGIC_1, sizeof (rl->__magic));
        (void) memcpy(rl->__encoding, frl->encoding, sizeof (rl->__encoding));

        rl->__variable_len = frl->variable_len;
        rl->__runetype_ext.__nranges = frl->runetype_ext_nranges;
        rl->__maplower_ext.__nranges = frl->maplower_ext_nranges;
        rl->__mapupper_ext.__nranges = frl->mapupper_ext_nranges;

        for (x = 0; x < _CACHED_RUNES; ++x) {
                rl->__runetype[x] = frl->runetype[x];
                rl->__maplower[x] = frl->maplower[x];
                rl->__mapupper[x] = frl->mapupper[x];
        }

        rl->__runetype_ext.__ranges = (_RuneEntry *)rl->__variable;
        rl->__variable = rl->__runetype_ext.__ranges +
            rl->__runetype_ext.__nranges;

        rl->__maplower_ext.__ranges = (_RuneEntry *)rl->__variable;
        rl->__variable = rl->__maplower_ext.__ranges +
            rl->__maplower_ext.__nranges;

        rl->__mapupper_ext.__ranges = (_RuneEntry *)rl->__variable;
        rl->__variable = rl->__mapupper_ext.__ranges +
            rl->__mapupper_ext.__nranges;

        variable = mapupper_ext_ranges + frl->mapupper_ext_nranges;
        frr = runetype_ext_ranges;
        rr = rl->__runetype_ext.__ranges;
        for (x = 0; x < rl->__runetype_ext.__nranges; ++x) {
                uint32_t *types;

                rr[x].__min = frr[x].min;
                rr[x].__max = frr[x].max;
                rr[x].__map = frr[x].map;
                if (rr[x].__map == 0) {
                        int len = rr[x].__max - rr[x].__min + 1;
                        types = variable;
                        variable = types + len;
                        rr[x].__types = rl->__variable;
                        rl->__variable = rr[x].__types + len;
                        while (len-- > 0)
                                rr[x].__types[len] = types[len];
                } else
                        rr[x].__types = NULL;
        }

        frr = maplower_ext_ranges;
        rr = rl->__maplower_ext.__ranges;
        for (x = 0; x < rl->__maplower_ext.__nranges; ++x) {
                rr[x].__min = frr[x].min;
                rr[x].__max = frr[x].max;
                rr[x].__map = frr[x].map;
        }

        frr = mapupper_ext_ranges;
        rr = rl->__mapupper_ext.__ranges;
        for (x = 0; x < rl->__mapupper_ext.__nranges; ++x) {
                rr[x].__min = frr[x].min;
                rr[x].__max = frr[x].max;
                rr[x].__map = frr[x].map;
        }

        (void) memcpy(rl->__variable, variable, rl->__variable_len);
        (void) munmap(fdata, sb.st_size);

        /*
         * Go out and zero pointers that should be zero.
         */
        if (!rl->__variable_len)
                rl->__variable = NULL;

        if (!rl->__runetype_ext.__nranges)
                rl->__runetype_ext.__ranges = NULL;

        if (!rl->__maplower_ext.__nranges)
                rl->__maplower_ext.__ranges = NULL;

        if (!rl->__mapupper_ext.__nranges)
                rl->__mapupper_ext.__ranges = NULL;

        return (rl);

invalid:
        (void) munmap(fdata, sb.st_size);
        errno = EINVAL;
        return (NULL);
}