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

/*-
 * 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>
#if defined(LIBC_SCCS) && !defined(lint)
__RCSID("$NetBSD: citrus_mapper_zone.c,v 1.4 2003/07/12 15:39:21 tshiozak Exp $");
#endif /* LIBC_SCCS and not lint */

#include <assert.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/queue.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 {
        u_int32_t z_begin;
        u_int32_t z_end;
};

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

struct _parse_state {
        enum { S_BEGIN, S_OFFSET }      ps_state;
        union {
                u_int32_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,
                                  size_t lenops, uint32_t expected_version)
{
        if (expected_version<_CITRUS_MAPPER_ABI_VERSION || lenops<sizeof(*ops))
                return EINVAL;

        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 sign = 0;
        int c, i;
        char buf[BUFSIZE+1], *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)
{
        u_int32_t remain;

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

        if (ofs > 0) {
                if (maxval == 0) {
                        /* this should 0x100000000 - z->z_end */
                        if (z->z_end == 0) {
                                remain = 0xFFFFFFFF;
                        } else {
                                remain = 0xFFFFFFFF - z->z_end + 1;
                        }
                } else
                        remain = maxval - z->z_end;
                if ((u_int32_t)ofs > remain)
                        return -1;
        } else if (ofs < 0) {
                if (z->z_begin < (u_int32_t)-ofs)
                        return -1;
        }

        return 0;
}

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

        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 */
        if (mz->mz_col_bits==32)
                colmax = 0;
        else
                colmax = 1 << mz->mz_col_bits;
        if (mz->mz_col_bits==0)
                rowmax = 0;
        else
                rowmax = 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,
                                struct _citrus_mapper * __restrict cm,
                                const char * __restrict dir,
                                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;

        _DIAGASSERT(cm && dir && mt);

        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, (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)
{
}

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)
{
        u_int32_t row, col;
        struct _citrus_mapper_zone *mz = cm->cm_closure;

        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 += (u_int32_t)mz->mz_col_offset;
                else
                        col -= (u_int32_t)-mz->mz_col_offset;
                *dst = col;
        } else {
                col = src & (((u_int32_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 += (u_int32_t)mz->mz_col_offset;
                else
                        col -= (u_int32_t)-mz->mz_col_offset;
                if (mz->mz_row_offset>0)
                        row += (u_int32_t)mz->mz_row_offset;
                else
                        row -= (u_int32_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(struct _citrus_mapper * __restrict cm,
                                      void * __restrict ps)
{
}