"A long time ago in a galaxy far, far away...." we started NFC subsystem refactoring. Starring: - @gornekich - NFC refactoring project lead, architect, senior developer - @gsurkov - architect, senior developer - @RebornedBrain - senior developer Supporting roles: - @skotopes, @DrZlo13, @hedger - general architecture advisors, code review - @Astrrra, @doomwastaken, @Hellitron, @ImagineVagon333 - quality assurance Special thanks: @bettse, @pcunning, @nxv, @noproto, @AloneLiberty and everyone else who has been helping us all this time and contributing valuable knowledges, ideas and source code.
		
			
				
	
	
		
			70 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			70 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| #include "nfc_util.h"
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| 
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| #include <furi.h>
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| 
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| static const uint8_t nfc_util_odd_byte_parity[256] = {
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|     1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0,
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|     1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1,
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|     1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1,
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|     0, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0,
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|     1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 1,
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|     0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0,
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|     0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1,
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|     0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
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|     1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1};
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| 
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| void nfc_util_num2bytes(uint64_t src, uint8_t len, uint8_t* dest) {
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|     furi_assert(dest);
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|     furi_assert(len <= 8);
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| 
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|     while(len--) {
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|         dest[len] = (uint8_t)src;
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|         src >>= 8;
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|     }
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| }
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| 
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| uint64_t nfc_util_bytes2num(const uint8_t* src, uint8_t len) {
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|     furi_assert(src);
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|     furi_assert(len <= 8);
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| 
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|     uint64_t res = 0;
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|     while(len--) {
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|         res = (res << 8) | (*src);
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|         src++;
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|     }
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|     return res;
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| }
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| 
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| uint8_t nfc_util_even_parity32(uint32_t data) {
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|     // data ^= data >> 16;
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|     // data ^= data >> 8;
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|     // return !nfc_util_odd_byte_parity[data];
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|     return (__builtin_parity(data) & 0xFF);
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| }
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| 
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| uint8_t nfc_util_odd_parity8(uint8_t data) {
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|     return nfc_util_odd_byte_parity[data];
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| }
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| 
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| void nfc_util_odd_parity(const uint8_t* src, uint8_t* dst, uint8_t len) {
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|     furi_assert(src);
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|     furi_assert(dst);
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| 
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|     uint8_t parity = 0;
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|     uint8_t bit = 0;
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|     while(len--) {
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|         parity |= nfc_util_odd_parity8(*src) << (7 - bit); // parity is MSB first
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|         bit++;
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|         if(bit == 8) {
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|             *dst = parity;
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|             dst++;
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|             parity = 0;
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|             bit = 0;
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|         }
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|         src++;
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|     }
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| 
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|     if(bit) {
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|         *dst = parity;
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|     }
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| } |