/*

 * libfdt - Flat Device Tree manipulation

 * Copyright (C) 2006 David Gibson, IBM Corporation.

 *

 * libfdt is dual licensed: you can use it either under the terms of

 * the GPL, or the BSD license, at your option.

 *

 *  a) This library is free software; you can redistribute it and/or

 *     modify it under the terms of the GNU General Public License as

 *     published by the Free Software Foundation; either version 2 of the

 *     License, or (at your option) any later version.

 *

 *     This library is distributed in the hope that it will be useful,

 *     but WITHOUT ANY WARRANTY; without even the implied warranty of

 *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 *     GNU General Public License for more details.

 *

 *     You should have received a copy of the GNU General Public

 *     License along with this library; if not, write to the Free

 *     Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,

 *     MA 02110-1301 USA

 *

 * Alternatively,

 *

 *  b) 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 COPYRIGHT HOLDERS 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 COPYRIGHT OWNER 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 "libfdt_env.h"

#include <fdt.h>

#include <libfdt.h>

#include "libfdt_internal.h"

int fdt_check_header(const void *fdt)

{

	if (fdt_magic(fdt) == FDT_MAGIC) {

		/* Complete tree */

		if (fdt_version(fdt) < FDT_FIRST_SUPPORTED_VERSION)

			return -FDT_ERR_BADVERSION;

		if (fdt_last_comp_version(fdt) > FDT_LAST_SUPPORTED_VERSION)

			return -FDT_ERR_BADVERSION;

	} else if (fdt_magic(fdt) == FDT_SW_MAGIC) {

		/* Unfinished sequential-write blob */

		if (fdt_size_dt_struct(fdt) == 0)

			return -FDT_ERR_BADSTATE;

	} else {

		return -FDT_ERR_BADMAGIC;

	}

	return 0;

}

const void *fdt_offset_ptr(const void *fdt, int offset, int len)

{

	const char *p;

	if (fdt_version(fdt) >= 0x11)

		if (((offset + len) < offset)

		    || ((offset + len) > fdt_size_dt_struct(fdt)))

			return NULL;

	p = _fdt_offset_ptr(fdt, offset);

	if (p + len < p)

		return NULL;

	return p;

}

uint32_t fdt_next_tag(const void *fdt, int offset, int *nextoffset)

{

	const uint32_t *tagp, *lenp;

	uint32_t tag;

	const char *p;

	if (offset % FDT_TAGSIZE)

		return -1;

	tagp = fdt_offset_ptr(fdt, offset, FDT_TAGSIZE);

	if (! tagp)

		return FDT_END; /* premature end */

	tag = fdt32_to_cpu(*tagp);

	offset += FDT_TAGSIZE;

	switch (tag) {

	case FDT_BEGIN_NODE:

		/* skip name */

		do {

			p = fdt_offset_ptr(fdt, offset++, 1);

		} while (p && (*p != '\0'));

		if (! p)

			return FDT_END;

		break;

	case FDT_PROP:

		lenp = fdt_offset_ptr(fdt, offset, sizeof(*lenp));

		if (! lenp)

			return FDT_END;

		/* skip name offset, length and value */

		offset += 2*FDT_TAGSIZE + fdt32_to_cpu(*lenp);

		break;

	}

	if (nextoffset)

		*nextoffset = FDT_TAGALIGN(offset);

	return tag;

}

int _fdt_check_node_offset(const void *fdt, int offset)

{

	if ((offset < 0) || (offset % FDT_TAGSIZE)

	    || (fdt_next_tag(fdt, offset, &offset) != FDT_BEGIN_NODE))

		return -FDT_ERR_BADOFFSET;

	return offset;

}

int fdt_next_node(const void *fdt, int offset, int *depth)

{

	int nextoffset = 0;

	uint32_t tag;

	if (offset >= 0)

		if ((nextoffset = _fdt_check_node_offset(fdt, offset)) < 0)

			return nextoffset;

	do {

		offset = nextoffset;

		tag = fdt_next_tag(fdt, offset, &nextoffset);

		switch (tag) {

		case FDT_PROP:

		case FDT_NOP:

			break;

		case FDT_BEGIN_NODE:

			if (depth)

				(*depth)++;

			break;

		case FDT_END_NODE:

			if (depth)

				(*depth)--;

			break;

		case FDT_END:

			return -FDT_ERR_NOTFOUND;

		default:

			return -FDT_ERR_BADSTRUCTURE;

		}

	} while (tag != FDT_BEGIN_NODE);

	return offset;

}

const char *_fdt_find_string(const char *strtab, int tabsize, const char *s)

{

	int len = strlen(s) + 1;

	const char *last = strtab + tabsize - len;

	const char *p;

	for (p = strtab; p <= last; p++)

		if (memcmp(p, s, len) == 0)

			return p;

	return NULL;

}

int fdt_move(const void *fdt, void *buf, int bufsize)

{

	FDT_CHECK_HEADER(fdt);

	if (fdt_totalsize(fdt) > bufsize)

		return -FDT_ERR_NOSPACE;

	memmove(buf, fdt, fdt_totalsize(fdt));

	return 0;

}