csu3_am335x/EVSE/GPL/open-plc-utils-0.3/nvm/manifetch.c

/*====================================================================*
 *
 *   Copyright (c) 2013 Qualcomm Atheros, Inc.
 *
 *   All rights reserved.
 *
 *   Redistribution and use in source and binary forms, with or
 *   without modification, are permitted (subject to the limitations
 *   in the disclaimer below) provided that the following conditions
 *   are met:
 *
 *   * Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   * 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.
 *
 *   * Neither the name of Qualcomm Atheros nor the names of
 *     its contributors may be used to endorse or promote products
 *     derived from this software without specific prior written
 *     permission.
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 *   GRANTED BY THIS LICENSE. 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
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 *   NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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 *--------------------------------------------------------------------*/

/*====================================================================*
 *
 *   void * manifetch (void const * memory, size_t extent);
 *
 *   nvm.h
 *
 *   search an nvm manifest for a given variable type and return a
 *   void pointer to the value, if present, or NULL if not; users
 *   must apply the correct type cast to the pointer to access the
 *   value;
 *
 *
 *   Contributor(s):
 *	Charles Maier
 *
 *--------------------------------------------------------------------*/

#ifndef MANIFETCH_SOURCE
#define MANIFETCH_SOURCE

#include <stdio.h>
#include <stdint.h>

#include "../tools/endian.h"
#include "../tools/tlv.h"

void * manifetch (void const * memory, size_t extent, uint32_t type)

{
	uint8_t * offset = (uint8_t *) (memory);
	while (extent)
	{
		struct TLVNode * node = (struct TLVNode *) (offset);
		if (LE32TOH (node->type) == type)
		{
			return ((void *) (& node->data));
		}
		extent -= TLVSPAN (node);
		offset += TLVSPAN (node);
	}
	return ((void *) (0));
}

#endif