mirror of
https://github.com/merbanan/rtl_433.git
synced 2026-04-20 09:37:00 -04:00
216 lines
6.5 KiB
C
216 lines
6.5 KiB
C
/**
|
|
* Various utility functions for use by device drivers
|
|
*
|
|
* Copyright (C) 2015 Tommy Vestermark
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*/
|
|
|
|
#ifndef INCLUDE_UTIL_H_
|
|
#define INCLUDE_UTIL_H_
|
|
|
|
#include <stdlib.h>
|
|
#include <stdint.h>
|
|
#include <stdbool.h>
|
|
#include <time.h>
|
|
|
|
|
|
#if defined _MSC_VER // Microsoft Visual Studio
|
|
#define restrict __restrict
|
|
#endif
|
|
|
|
// Helper macros
|
|
#ifndef max
|
|
#define max(a,b) ((a) > (b) ? (a) : (b))
|
|
#endif
|
|
#ifndef min
|
|
#define min(a,b) ((a) < (b) ? (a) : (b))
|
|
#endif
|
|
|
|
/// Reverse the bits in an 8 bit byte
|
|
/// @param x: input byte
|
|
/// @return bit reversed byte
|
|
uint8_t reverse8(uint8_t x);
|
|
|
|
/// CRC-4
|
|
///
|
|
/// @param message[]: array of bytes to check
|
|
/// @param nBytes: number of bytes in message
|
|
/// @param polynomial: CRC polynomial
|
|
/// @param init: starting crc value
|
|
/// @return CRC value
|
|
uint8_t crc4(uint8_t const message[], unsigned nBytes, uint8_t polynomial, uint8_t init);
|
|
|
|
/// CRC-7
|
|
///
|
|
/// @param message[]: array of bytes to check
|
|
/// @param nBytes: number of bytes in message
|
|
/// @param polynomial: CRC polynomial
|
|
/// @param init: starting crc value
|
|
/// @return CRC value
|
|
uint8_t crc7(uint8_t const message[], unsigned nBytes, uint8_t polynomial, uint8_t init);
|
|
|
|
/// Generic Cyclic Redundancy Check CRC-8
|
|
///
|
|
/// Example polynomial: 0x31 = x8 + x5 + x4 + 1 (x8 is implicit)
|
|
/// Example polynomial: 0x80 = x8 + x7 (a normal bit-by-bit parity XOR)
|
|
///
|
|
/// @param message[]: array of bytes to check
|
|
/// @param nBytes: number of bytes in message
|
|
/// @param polynomial: byte is from x^7 to x^0 (x^8 is implicitly one)
|
|
/// @param init: starting crc value
|
|
/// @return CRC value
|
|
uint8_t crc8(uint8_t const message[], unsigned nBytes, uint8_t polynomial, uint8_t init);
|
|
|
|
/// "Little-endian" Cyclic Redundancy Check CRC-8 LE
|
|
///
|
|
/// Based on code generated from PyCyc, (pycrc.org)
|
|
///
|
|
/// @param message[]: array of bytes to check
|
|
/// @param nBytes: number of bytes in message
|
|
/// @param polynomial: CRC polynomial
|
|
/// @param init: starting crc value
|
|
/// @return CRC value
|
|
uint8_t crc8le(uint8_t const message[], unsigned nBytes, uint8_t polynomial, uint8_t init);
|
|
|
|
/// CRC-16
|
|
///
|
|
/// @param message[]: array of bytes to check
|
|
/// @param nBytes: number of bytes in message
|
|
/// @param polynomial: CRC polynomial
|
|
/// @param init: starting crc value
|
|
/// @return CRC value
|
|
uint16_t crc16(uint8_t const message[], unsigned nBytes, uint16_t polynomial, uint16_t init);
|
|
|
|
/// CRC-16 CCITT
|
|
///
|
|
/// @param message[]: array of bytes to check
|
|
/// @param nBytes: number of bytes in message
|
|
/// @param polynomial: CRC polynomial
|
|
/// @param init: starting crc value
|
|
/// @return CRC value
|
|
uint16_t crc16_ccitt(uint8_t const message[], unsigned nBytes, uint16_t polynomial, uint16_t init);
|
|
|
|
/// Digest-8 by "LFSR-based Toeplitz hash"
|
|
/// @param message bytes of message data
|
|
/// @param bytes number of bytes to digest
|
|
/// @param gen key stream generator, needs to includes the MSB if the LFSR is rolling
|
|
/// @param key initial key
|
|
/// @return digest value
|
|
uint8_t lfsr_digest8(uint8_t const message[], unsigned bytes, uint8_t gen, uint8_t key);
|
|
|
|
/// Digest-16 by "LFSR-based Toeplitz hash"
|
|
/// @param data up to 32 bits data, LSB aligned
|
|
/// @param bits number of bits to digest
|
|
/// @param gen key stream generator, needs to includes the MSB if the LFSR is rolling
|
|
/// @param key initial key
|
|
/// @return digest value
|
|
uint16_t lfsr_digest16(uint32_t data, int bits, uint16_t gen, uint16_t key);
|
|
|
|
/// compute bit parity of a single byte
|
|
///
|
|
/// @param inByte: single byte to check
|
|
/// @return 1 odd parity, 0 even parity
|
|
int byteParity(uint8_t inByte);
|
|
|
|
// buffer to hold localized timestamp YYYY-MM-DD HH:MM:SS
|
|
#define LOCAL_TIME_BUFLEN 32
|
|
|
|
/// Printable timestamp in local time
|
|
///
|
|
/// @param time_secs: 0 for now, or seconds since the epoch
|
|
/// @param buf: output buffer, long enough for YYYY-MM-DD HH:MM:SS
|
|
/// @return buf pointer (for short hand use as operator)
|
|
char* local_time_str(time_t time_secs, char *buf);
|
|
|
|
/// Convert Celsius to Fahrenheit
|
|
///
|
|
/// @param celsius: temperature in Celsius
|
|
/// @return temperature value in Fahrenheit
|
|
float celsius2fahrenheit(float celsius);
|
|
|
|
|
|
/// Convert Fahrenheit to Celsius
|
|
///
|
|
/// @param celsius: temperature in Fahrenheit
|
|
/// @return temperature value in Celsius
|
|
float fahrenheit2celsius(float fahrenheit);
|
|
|
|
|
|
/// Convert Kilometers per hour (kph) to Miles per hour (mph)
|
|
///
|
|
/// @param kph: speed in Kilometers per hour
|
|
/// @return speed in miles per hour
|
|
float kmph2mph(float kph);
|
|
|
|
/// Convert Miles per hour (mph) to Kilometers per hour (kmph)
|
|
///
|
|
/// @param mph: speed in Kilometers per hour
|
|
/// @return speed in kilometers per hour
|
|
float mph2kmph(float kph);
|
|
|
|
|
|
/// Convert millimeters (mm) to inches (inch)
|
|
///
|
|
/// @param mm: measurement in millimeters
|
|
/// @return measurement in inches
|
|
float mm2inch(float mm);
|
|
|
|
/// Convert inches (inch) to millimeters (mm)
|
|
///
|
|
/// @param inch: measurement in inches
|
|
/// @return measurement in millimeters
|
|
float inch2mm(float inch);
|
|
|
|
|
|
/// Convert kilo Pascal (kPa) to pounds per square inch (PSI)
|
|
///
|
|
/// @param kpa: pressure in kPa
|
|
/// @return pressure in PSI
|
|
float kpa2psi(float kpa);
|
|
|
|
/// Convert pounds per square inch (PSI) to kilo Pascal (kPa)
|
|
///
|
|
/// @param psi: pressure in PSI
|
|
/// @return pressure in kPa
|
|
float psi2kpa(float psi);
|
|
|
|
|
|
/// Convert hecto Pascal (hPa) to inches of mercury (inHg)
|
|
///
|
|
/// @param kpa: pressure in kPa
|
|
/// @return pressure in inHg
|
|
float hpa2inhg(float hpa);
|
|
|
|
/// Convert inches of mercury (inHg) to hecto Pascal (hPa)
|
|
///
|
|
/// @param kpa: pressure in inHg
|
|
/// @return pressure in hPa
|
|
float inhg2hpa(float inhg);
|
|
|
|
|
|
/// Return true if the string ends with the specified suffix, otherwise return false.
|
|
///
|
|
/// @param str: string to search for patterns
|
|
/// @param suffix: the pattern to search
|
|
/// @return true if the string ends with the specified suffix, false otherwise.
|
|
bool str_endswith(const char *restrict str, const char *restrict suffix);
|
|
|
|
/// Replace a pattern in a string. This utility function is
|
|
/// useful when converting native units to si or customary.
|
|
///
|
|
/// @param orig: string to search for patterns
|
|
/// @param rep: the pattern to replace
|
|
/// @param with: the replacement pattern
|
|
/// @return a new string that has rep replaced with with
|
|
char *str_replace(char *orig, char *rep, char *with);
|
|
|
|
/// Make a nice printable string for a frequency.
|
|
///
|
|
/// @param freq: the frequency to convert to a string.
|
|
const char *nice_freq (double freq);
|
|
|
|
#endif /* INCLUDE_UTIL_H_ */
|