/*      $NetBSD: citrus_mapper_zone.c,v 1.4 2003/07/12 15:39:21 tshiozak Exp $  */

/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * 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 <sys/cdefs.h>
#include <sys/queue.h>

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

#include "citrus_namespace.h"
#include "citrus_types.h"
#include "citrus_bcs.h"
#include "citrus_module.h"
#include "citrus_region.h"
#include "citrus_memstream.h"
#include "citrus_mmap.h"
#include "citrus_hash.h"
#include "citrus_mapper.h"
#include "citrus_mapper_zone.h"

/* ---------------------------------------------------------------------- */

_CITRUS_MAPPER_DECLS(mapper_zone);
_CITRUS_MAPPER_DEF_OPS(mapper_zone);


/* ---------------------------------------------------------------------- */

struct _zone {
        uint32_t         z_begin;
        uint32_t         z_end;
};

struct _citrus_mapper_zone {
        struct _zone     mz_col;
        struct _zone     mz_row;
        int32_t          mz_col_offset;
        int32_t          mz_row_offset;
        int              mz_col_bits;
};

struct _parse_state {
        enum { S_BEGIN, S_OFFSET }      ps_state;
        union {
                uint32_t        u_imm;
                int32_t         s_imm;
                struct _zone    zone;
        } u;
#define ps_u_imm        u.u_imm
#define ps_s_imm        u.s_imm
#define ps_zone         u.zone
        int ps_top;
};

int
_citrus_mapper_zone_mapper_getops(struct _citrus_mapper_ops *ops)
{

        memcpy(ops, &_citrus_mapper_zone_mapper_ops,
               sizeof(_citrus_mapper_zone_mapper_ops));

        return (0);
}

#define BUFSIZE 20
#define T_ERR   0x100
#define T_IMM   0x101

static int
get_imm(struct _memstream *ms, struct _parse_state *ps)
{
        int c, i, sign = 0;
        char buf[BUFSIZE + 1];
        char *p;

        for (i = 0; i < BUFSIZE; i++) {
retry:
                c = _memstream_peek(ms);
                if (i == 0) {
                        if (sign == 0 && (c == '+' || c == '-')) {
                                sign = c;
                                _memstream_getc(ms);
                                goto retry;
                        } else if (!_bcs_isdigit(c))
                                break;
                } else if (!_bcs_isxdigit(c))
                        if (!(i == 1 && c == 'x'))
                                break;
                buf[i] = _memstream_getc(ms);
        }
        buf[i] = '\0';
        ps->ps_u_imm = strtoul(buf, &p, 0);
        if ((p - buf) != i)
                return (T_ERR);
        if (sign == '-')
                ps->ps_u_imm = (unsigned long)-(long)ps->ps_u_imm;
        return (T_IMM);
}

static int
get_tok(struct _memstream *ms, struct _parse_state *ps)
{
        int c;

loop:
        c = _memstream_peek(ms);
        if (c == 0x00)
                return (EOF);
        if (_bcs_isspace(c)) {
                _memstream_getc(ms);
                goto loop;
        }

        switch (ps->ps_state) {
        case S_BEGIN:
                switch (c) {
                case ':':
                case '-':
                case '/':
                        _memstream_getc(ms);
                        return (c);
                case '0':
                case '1':
                case '2':
                case '3':
                case '4':
                case '5':
                case '6':
                case '7':
                case '8':
                case '9':
                        return (get_imm(ms, ps));
                }
                break;
        case S_OFFSET:
                switch (c) {
                case '/':
                        _memstream_getc(ms);
                        return (c);
                case '+':
                case '-':
                case '0':
                case '1':
                case '2':
                case '3':
                case '4':
                case '5':
                case '6':
                case '7':
                case '8':
                case '9':
                        return (get_imm(ms, ps));
                }
                break;
        }
        return (T_ERR);
}

static int
parse_zone(struct _memstream *ms, struct _parse_state *ps, struct _zone *z)
{

        if (get_tok(ms, ps) != T_IMM)
                return (-1);
        z->z_begin = ps->ps_u_imm;
        if (get_tok(ms, ps) != '-')
                return (-1);
        if (get_tok(ms, ps) != T_IMM)
                return (-1);
        z->z_end = ps->ps_u_imm;

        if (z->z_begin > z->z_end)
                return (-1);

        return (0);
}

static int
check_rowcol(struct _zone *z, int32_t ofs, uint32_t maxval)
{
        uint32_t remain;

        if (maxval != 0 && z->z_end >= maxval)
                return (-1);

        if (ofs > 0) {
                if (maxval == 0)
                        /* this should 0x100000000 - z->z_end */
                        remain = (z->z_end == 0) ? 0xFFFFFFFF :
                            0xFFFFFFFF - z->z_end + 1;
                else
                        remain = maxval - z->z_end;
                if ((uint32_t)ofs > remain)
                        return (-1);
        } else if (ofs < 0) {
                if (z->z_begin < (uint32_t)-ofs)
                        return (-1);
        }

        return (0);
}

static int
parse_var(struct _citrus_mapper_zone *mz, struct _memstream *ms)
{
        struct _parse_state ps;
        uint32_t colmax, rowmax;
        int isrc, ret;

        ps.ps_state = S_BEGIN;

        if (parse_zone(ms, &ps, &mz->mz_col))
                return (-1);

        ret = get_tok(ms, &ps);
        if (ret == '/') {
                /* rowzone / colzone / bits */
                isrc = 1;
                mz->mz_row = mz->mz_col;

                if (parse_zone(ms, &ps, &mz->mz_col))
                        return (-1);
                if (get_tok(ms, &ps) != '/')
                        return (-1);
                if (get_tok(ms, &ps) != T_IMM)
                        return (-1);
                mz->mz_col_bits = ps.ps_u_imm;
                if (mz->mz_col_bits < 0 || mz->mz_col_bits > 32)
                        return (-1);
                ret = get_tok(ms, &ps);
        } else {
                /* colzone */
                isrc = 0;
                mz->mz_col_bits = 32;
                mz->mz_row.z_begin = mz->mz_row.z_end = 0;
        }
        if (ret == ':') {
                /* offset */
                ps.ps_state = S_OFFSET;
                if (get_tok(ms, &ps) != T_IMM)
                        return (-1);
                mz->mz_col_offset = ps.ps_s_imm;
                if (isrc) {
                        /* row/col */
                        mz->mz_row_offset = mz->mz_col_offset;
                        if (get_tok(ms, &ps) != '/')
                                return (-1);
                        if (get_tok(ms, &ps) != T_IMM)
                                return (-1);
                        mz->mz_col_offset = ps.ps_s_imm;
                } else
                        mz->mz_row_offset = 0;
                ret = get_tok(ms, &ps);
        }
        if (ret != EOF)
                return (-1);

        /* sanity check */
        colmax = (mz->mz_col_bits == 32) ? 0 : 1 << mz->mz_col_bits;
        rowmax = (mz->mz_col_bits == 0) ? 0 : 1 << (32-mz->mz_col_bits);
        if (check_rowcol(&mz->mz_col, mz->mz_col_offset, colmax))
                return (-1);
        if (check_rowcol(&mz->mz_row, mz->mz_row_offset, rowmax))
                return (-1);

        return (0);
}

static int
/*ARGSUSED*/
_citrus_mapper_zone_mapper_init(struct _citrus_mapper_area *__restrict ma __unused,
    struct _citrus_mapper * __restrict cm, const char * __restrict dir __unused,
    const void * __restrict var, size_t lenvar,
    struct _citrus_mapper_traits * __restrict mt, size_t lenmt)
{
        struct _citrus_mapper_zone *mz;
        struct _memstream ms;
        struct _region r;

        if (lenmt < sizeof(*mt))
                return (EINVAL);

        mz = malloc(sizeof(*mz));
        if (mz == NULL)
                return (errno);

        mz->mz_col.z_begin = mz->mz_col.z_end = 0;
        mz->mz_row.z_begin = mz->mz_row.z_end = 0;
        mz->mz_col_bits = 0;
        mz->mz_row_offset = 0;
        mz->mz_col_offset = 0;

        _region_init(&r, __DECONST(void *, var), lenvar);
        _memstream_bind(&ms, &r);
        if (parse_var(mz, &ms)) {
                free(mz);
                return (EINVAL);
        }
        cm->cm_closure = mz;
        mt->mt_src_max = mt->mt_dst_max = 1;    /* 1:1 converter */
        mt->mt_state_size = 0;                  /* stateless */

        return (0);
}

static void
/*ARGSUSED*/
_citrus_mapper_zone_mapper_uninit(struct _citrus_mapper *cm __unused)
{

}

static int
/*ARGSUSED*/
_citrus_mapper_zone_mapper_convert(struct _citrus_mapper * __restrict cm,
    _citrus_index_t * __restrict dst, _citrus_index_t src,
    void * __restrict ps __unused)
{
        struct _citrus_mapper_zone *mz = cm->cm_closure;
        uint32_t col, row;

        if (mz->mz_col_bits == 32) {
                col = src;
                row = 0;
                if (col < mz->mz_col.z_begin || col > mz->mz_col.z_end)
                        return (_CITRUS_MAPPER_CONVERT_NONIDENTICAL);
                if (mz->mz_col_offset > 0)
                        col += (uint32_t)mz->mz_col_offset;
                else
                        col -= (uint32_t)-mz->mz_col_offset;
                *dst = col;
        } else {
                col = src & (((uint32_t)1 << mz->mz_col_bits) - 1);
                row = src >> mz->mz_col_bits;
                if (row < mz->mz_row.z_begin || row > mz->mz_row.z_end ||
                    col < mz->mz_col.z_begin || col > mz->mz_col.z_end)
                        return (_CITRUS_MAPPER_CONVERT_NONIDENTICAL);
                if (mz->mz_col_offset > 0)
                        col += (uint32_t)mz->mz_col_offset;
                else
                        col -= (uint32_t)-mz->mz_col_offset;
                if (mz->mz_row_offset > 0)
                        row += (uint32_t)mz->mz_row_offset;
                else
                        row -= (uint32_t)-mz->mz_row_offset;
                *dst = col | (row << mz->mz_col_bits);
        }
        return (_CITRUS_MAPPER_CONVERT_SUCCESS);
}

static void
/*ARGSUSED*/
_citrus_mapper_zone_mapper_init_state(void)
{

}