| 
						
						
							
								
							
						
						
					 | 
				
				 | 
				 | 
				
					@ -10,6 +10,7 @@
					 | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					
 | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					/// used to generate up a [u32; 256] lookup table in `crc32`. this computes
 | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					/// the table on demand for a given "index" `i`
 | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					#[rustfmt::skip] | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					const fn table_fn(i: u32) -> u32 { | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					    let mut out = i; | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					
 | 
				
			
			
		
	
	
		
			
				
					| 
						
							
								
							
						
						
							
								
							
						
						
					 | 
				
				 | 
				 | 
				
					@ -101,12 +102,10 @@ mod tests {
					 | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					    fn crc32_compute_table() -> [u32; 256] { | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					        let mut crc32_table = [0; 256]; | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					
 | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					        for n in 0..256 { | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					            crc32_table[n as usize] = (0..8).fold(n as u32, |acc, _| { | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					                match acc & 1 { | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					                    1 => 0xedb88320 ^ (acc >> 1), | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					                    _ => acc >> 1, | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					                } | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					        for n in 0..256_u32 { | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					            crc32_table[n as usize] = (0..8).fold(n, |acc, _| match acc & 1 { | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					                1 => 0xedb88320 ^ (acc >> 1), | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					                _ => acc >> 1, | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					            }); | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					        } | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					
 | 
				
			
			
		
	
	
		
			
				
					| 
						
						
						
							
								
							
						
					 | 
				
				 | 
				 | 
				
					@ -116,7 +115,7 @@ mod tests {
					 | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					    #[test] | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					    fn check_table_fn_against_example_code() { | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					        let table = crc32_compute_table(); | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					        for i in 0..256{ | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					        for i in 0..256 { | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					            assert_eq!(table[i], table_fn(i as u32)); | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					        } | 
				
			
			
		
	
		
			
				
					 | 
					 | 
				
				 | 
				 | 
				
					    } | 
				
			
			
		
	
	
		
			
				
					| 
						
							
								
							
						
						
						
					 | 
				
				 | 
				 | 
				
					
 
					 |