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/*
* Copyright (C) 2017 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef HEADER_HDLC_LITE_H_INCLUDED
#define HEADER_HDLC_LITE_H_INCLUDED 1
#include <stdint.h>
#include <stdbool.h>
#if defined(__cplusplus)
extern "C" {
#endif
static const uint8_t kHdlcResetSignal[] = { 0x7E, 0x13, 0x11, 0x7E };
static const uint16_t kHdlcCrcCheckValue = 0xf0b8;
static const uint16_t kHdlcCrcResetValue = 0xffff;
#define HDLC_BYTE_FLAG 0x7E
#define HDLC_BYTE_ESC 0x7D
#define HDLC_BYTE_XON 0x11
#define HDLC_BYTE_XOFF 0x13
#define HDLC_BYTE_SPECIAL 0xF8
#define HDLC_ESCAPE_XFORM 0x20
/** HDLC CRC function */
extern uint16_t hdlc_crc16(uint16_t fcs, uint8_t byte);
/** HDLC CRC Finalize function */
extern uint16_t hdlc_crc16_finalize(uint16_t fcs);
/** Returns true if the byte needs to be escaped, false otherwise */
extern bool hdlc_byte_needs_escape(uint8_t byte);
/**
* Writes one or two HDLC-encoded bytes to out_buffer,
* and returns how many bytes were written.
*/
extern int hdlc_write_byte(uint8_t* out_buffer, uint8_t byte);
#if defined(__cplusplus)
}
#endif
#endif // HEADER_HDLC_LITE_H_INCLUDED
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