freebsd-dev/lib/libefivar/efivar-dp.h

/*-
 * Copyright (c) 2017 Netflix, Inc.
 * 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
 *    in this position and unchanged.
 * 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 ``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 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.
 *
 * $FreeBSD$
 */

#ifndef	_EFIVAR_DP_H_
#define	_EFIVAR_DP_H_

/*
 * "Linux compatible" efivar-dp.h header. At the moment, it's really a
 * very thin, minimal interface.
 */

/*
 * Generic EFI_DEVICE_PATH, spelled the Linux way. We use this
 * interface to the outside world and type-pun to the EFI EDK2 code
 * we use to implement it.
 */
typedef struct {
	uint8_t type;
	uint8_t subtype;
	uint16_t length;
} __packed efidp_header;

/* NB: Linux has shadow types for all dp type */

typedef union {
        efidp_header header;
} efidp_data;
typedef efidp_data *efidp;
typedef const efidp_data *const_efidp;

/** format a device path into UEFI standard conforming output.
 *
 * NB: FreeBSD's implementation is taken from EDK2, while Linux's
 * was hand-rolled. There may be differences as a result.
 */
ssize_t efidp_format_device_path(char *buf, size_t len, const_efidp dp,
    ssize_t max);
ssize_t efidp_parse_device_path(char *path, efidp out, size_t max);

size_t efidp_size(const_efidp);

#endif /* _EFIVAR_DP_H_ */