/*
 * Copyright 2019 The Chromium OS Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 *
 * This is a copy from upstream:
 * https://chromium.googlesource.com/chromiumos/platform/vpd/+/master/include/lib/vpd_decode.h
 */

#ifndef __VPD_DECODE_H
#define __VPD_DECODE_H

#include <stdint.h>

enum {
	VPD_DECODE_OK = 0,
	VPD_DECODE_FAIL = 1,
};

enum {
	VPD_TYPE_TERMINATOR = 0,
	VPD_TYPE_STRING,
	VPD_TYPE_INFO = 0xfe,
	VPD_TYPE_IMPLICIT_TERMINATOR = 0xff,
};

/* Callback for vpd_decode_string to invoke. */
typedef int vpd_decode_callback(
		const u8 *key, u32 key_len, const u8 *value, u32 value_len,
		void *arg);

/*
 * vpd_decode_len
 *
 * Given an encoded string, this function extracts the length of content
 * (either key or value). The *consumed will contain the number of bytes
 * consumed.
 *
 * The input_buf points to the first byte of the input buffer.
 *
 * The *consumed starts from 0, which is actually the next byte to be decoded.
 * It can be non-zero to be used in multiple calls.
 *
 * Returns VPD_DECODE_OK on success, otherwise VPD_DECODE_FAIL.
 */
int vpd_decode_len(
		const u32 max_len, const u8 *in, u32 *length, u32 *decoded_len);

/*
 * vpd_decode_string
 *
 * Given the encoded string, this function invokes callback with extracted
 * (key, value). The *consumed will be plused the number of bytes consumed in
 * this function.
 *
 * The input_buf points to the first byte of the input buffer.
 *
 * The *consumed starts from 0, which is actually the next byte to be decoded.
 * It can be non-zero to be used in multiple calls.
 *
 * If one entry is successfully decoded, sends it to callback and returns the
 * result.
 */
int vpd_decode_string(
		const u32 max_len, const u8 *input_buf, u32 *consumed,
		vpd_decode_callback callback, void *callback_arg);

#endif  /* __VPD_DECODE_H */