freebsd-skq/sys/dev/bhnd/nvram/bhnd_nvram_valuevar.h
landonf 55e6f51da0 bhnd(4): support direct conversion of bhnd_nvram_val
This adds support for bhnd_nvram_val_convert_init() and
bhnd_nvram_val_convert_new(), which may be used to perform value
format-aware encoding of an NVRAM value to a new target format/type.

This will be used to simplify converting to/from serialized
format-specific NVRAM value representations to common external
representations.

Approved by:	adrian (mentor)
Differential Revision:	https://reviews.freebsd.org/D8757
2016-12-19 20:20:33 +00:00

101 lines
3.9 KiB
C

/*-
* Copyright (c) 2015-2016 Landon Fuller <landonf@FreeBSD.org>
* 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,
* without modification.
* 2. Redistributions in binary form must reproduce at minimum a disclaimer
* similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
* redistribution must be conditioned upon including a substantially
* similar Disclaimer requirement for further binary redistribution.
*
* NO WARRANTY
* 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 NONINFRINGEMENT, MERCHANTIBILITY
* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR 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 DAMAGES.
*
* $FreeBSD$
*/
#ifndef _BHND_NVRAM_BHND_NVRAM_VALUEVAR_H_
#define _BHND_NVRAM_BHND_NVRAM_VALUEVAR_H_
#include "bhnd_nvram_value.h"
int bhnd_nvram_val_generic_encode(bhnd_nvram_val *value,
void *outp, size_t *olen, bhnd_nvram_type otype);
int bhnd_nvram_val_generic_encode_elem(bhnd_nvram_val *value,
const void *inp, size_t ilen, void *outp, size_t *olen,
bhnd_nvram_type otype);
const void *bhnd_nvram_val_generic_next(bhnd_nvram_val *value,
const void *prev, size_t *olen);
/**
* Filter input data prior to initialization.
*
* This may be used to permit direct initialization from data types other than
* the default native_type defined by @p fmt.
*
* @param[in,out] fmt Indirect pointer to the NVRAM value format. If
* modified by the caller, initialization will be
* restarted and performed using the provided
* format instance.
* @param inp Input data.
* @param ilen Input data length.
* @param itype Input data type.
*
* @retval 0 If initialization from @p inp is supported.
* @retval EFTYPE If initialization from @p inp is unsupported.
* @retval EFAULT if @p ilen is not correctly aligned for elements of
* @p itype.
*/
typedef int (bhnd_nvram_val_op_filter)(const bhnd_nvram_val_fmt **fmt,
const void *inp, size_t ilen, bhnd_nvram_type itype);
/** @see bhnd_nvram_val_encode() */
typedef int (bhnd_nvram_val_op_encode)(bhnd_nvram_val *value, void *outp,
size_t *olen, bhnd_nvram_type otype);
/** @see bhnd_nvram_val_encode_elem() */
typedef int (bhnd_nvram_val_op_encode_elem)(bhnd_nvram_val *value,
const void *inp, size_t ilen, void *outp, size_t *olen,
bhnd_nvram_type otype);
/** @see bhnd_nvram_val_next() */
typedef const void *(bhnd_nvram_val_op_next)(bhnd_nvram_val *value,
const void *prev, size_t *olen);
/** @see bhnd_nvram_val_nelem() */
typedef size_t (bhnd_nvram_val_op_nelem)(bhnd_nvram_val *value);
/**
* NVRAM value format.
*
* Provides a set of callbacks to support defining custom parsing
* and encoding/conversion behavior when representing values as
* instances of bhnd_nvram_val.
*/
struct bhnd_nvram_val_fmt {
const char *name; /**< type name */
bhnd_nvram_type native_type; /**< native value representation */
bhnd_nvram_val_op_filter *op_filter;
bhnd_nvram_val_op_encode *op_encode;
bhnd_nvram_val_op_encode_elem *op_encode_elem;
bhnd_nvram_val_op_nelem *op_nelem;
bhnd_nvram_val_op_next *op_next;
};
#endif /* _BHND_NVRAM_BHND_NVRAM_VALUEVAR_H_ */