/*	$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)
{
}