433_STM32/Core/Src/fifo.c

#include "fifo.h"

#define MIN(a, b) (((a) < (b)) ? (a) : (b))


fifo_error_t fifo_create( fifo_t *fifo , uint8_t *buffer, uint32_t size )
{
		/* <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> */
		if( (fifo == 0) || (buffer == 0) || (size == 0) )
		{
			return FIFO_ERROR_NULL;
		}
		
		/* <20><><EFBFBD>ȼ<EFBFBD><C8BC><EFBFBD> (<28><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>2^n) */
		if( size & (size - 1) )
		{
			return FIFO_ERROR_LENGTH;
		}
		
		/* Ĭ<><C4AC> */
		fifo->size = size;
		fifo->buffer = buffer;
		fifo->in = 0;
		fifo->out = 0;
		
		return FIFO_OK;
}

fifo_error_t fifo_clear( fifo_t *fifo )
{
		/* <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> */
		if( fifo == 0 ) 
		{
			return FIFO_ERROR_NULL;
		}
		
    fifo->in = 0;
    fifo->out = 0;
	
    return FIFO_OK;
}


fifo_error_t fifo_write( fifo_t *fifo, uint8_t *buffer, uint32_t length )
{
    uint32_t i, j;
    uint32_t end_length, org_length;
    uint8_t *fifo_buffer;

		/* <20><>¼ԭʼ<D4AD>û<EFBFBD>д<EFBFBD>볤<EFBFBD><EBB3A4> */
    org_length = length;
	
    /* <20><><EFBFBD><EFBFBD>FIFOʣ<4F><CAA3><EFBFBD><EFBFBD><EFBFBD><EFBFBD> */
    length = MIN( length, fifo->size - fifo->in + fifo->out );
	
    /* <20><><EFBFBD><EFBFBD>FIFO<46><4F><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ĩβ<C4A9>Ƿ<EFBFBD><C7B7><EFBFBD><EFBFBD><EFBFBD><EFBFBD>㹻λ<E3B9BB><CEBB> */
    end_length  = MIN( length, fifo->size - ( fifo->in & ( fifo->size - 1 ) ) );
	
		/* <20>ҵ<EFBFBD>FIFO<46><4F>д<EFBFBD><D0B4><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʼ<EFBFBD><CABC>ַ */
    fifo_buffer = fifo->buffer + ( fifo->in & ( fifo->size - 1 ) );
	
		/* <20><><EFBFBD><EFBFBD>FIFOĩβ<C4A9><CEB2><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>û<EFBFBD><C3BB><EFBFBD><EFBFBD>ݸ<EFBFBD><DDB8>Ƶ<EFBFBD>FIFO<46><4F><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ĩβ */
    for( i = 0; i < end_length; i++ )
    {
        *( fifo_buffer++ ) = *( buffer++ );
    }
    
		/* <20><><EFBFBD><EFBFBD><EFBFBD>û<EFBFBD><C3BB><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ƿ<EFBFBD><C7B7><EFBFBD>ȫ<EFBFBD><C8AB><EFBFBD><EFBFBD><EFBFBD><EFBFBD> */
    j = length - end_length;
		
		/* <20><><EFBFBD><EFBFBD><EFBFBD>û<EFBFBD><C3BB><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʣ<EFBFBD>࣬<EFBFBD><E0A3AC><EFBFBD><EFBFBD>Ҫ<EFBFBD><D2AA>FIFO<46><4F><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ͷ<EFBFBD><CDB7><EFBFBD><EFBFBD>ʼ<EFBFBD><CABC><EFBFBD><EFBFBD>*/
    if ( j > 0 )
    {
        fifo_buffer = fifo->buffer;

        for( i = 0; i < j; i++ )
        {
            *( fifo_buffer++ ) = *( buffer++ );
        }
    }

		/* <20><>¼<EFBFBD>ѽ<EFBFBD><D1BD><EFBFBD>FIFO<46>ij<EFBFBD><C4B3><EFBFBD> */
    fifo->in += length;
		
		/* <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>FIFO<46><4F><EFBFBD>ݵij<DDB5><C4B3><EFBFBD>С<EFBFBD><D0A1><EFBFBD>û<EFBFBD>ʵ<EFBFBD><CAB5>д<EFBFBD><D0B4><EFBFBD><EFBFBD><EFBFBD>ݵij<DDB5><C4B3>ȣ<EFBFBD><C8A3>Ǿ<EFBFBD><C7BE><EFBFBD>FIFO<46><4F><EFBFBD><EFBFBD>װ<EFBFBD><D7B0><EFBFBD><EFBFBD><EFBFBD><EFBFBD> */
    if( length < org_length )
    {
        return FIFO_ERROR_FULL;
    }
		
    return FIFO_OK;
}

fifo_error_t fifo_read( fifo_t *fifo, uint8_t *buffer,  uint32_t length )
{
    uint32_t i, j;
    uint32_t end_length, org_length;
    uint8_t *fifo_buffer;

		/* <20><>¼ԭʼ<D4AD>û<EFBFBD><C3BB><EFBFBD>ȡ<EFBFBD><C8A1><EFBFBD><EFBFBD> */
    org_length = length;
	
		/* <20><><EFBFBD><EFBFBD>FIFO<46><4F><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ݳ<EFBFBD><DDB3><EFBFBD> */
    length  = MIN( length, fifo->in - fifo->out );
	
    /* <20><><EFBFBD><EFBFBD>FIFOĩβ<C4A9><CEB2><EFBFBD>ӳ<EFBFBD><D3B3><EFBFBD> */
    end_length = MIN( length, fifo->size - ( fifo->out & ( fifo->size - 1 ) ) );
	
		/* <20>ҵ<EFBFBD>FIFOĩβ<C4A9><CEB2><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʼ<EFBFBD><CABC>ַ */
    fifo_buffer = fifo->buffer + ( fifo->out & ( fifo->size - 1 ) );
	
		/* <20><><EFBFBD><EFBFBD>FIFOĩβ<C4A9><CEB2><EFBFBD><EFBFBD><EFBFBD>ݳ<EFBFBD><DDB3>ӣ<EFBFBD><D3A3><EFBFBD><EFBFBD><EFBFBD>FIFO<46>ڸ<EFBFBD><DAB8>Ƹ<EFBFBD><C6B8>û<EFBFBD><C3BB><EFBFBD><EFBFBD>ݻ<EFBFBD><DDBB><EFBFBD> */
    for( i = 0; i < end_length; i++ )
    {
        *( buffer++ ) = *( fifo_buffer++ );
    }
		
    /* <20><><EFBFBD><EFBFBD><EFBFBD>û<EFBFBD><C3BB><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ƿ<EFBFBD><C7B7><EFBFBD>ȫ<EFBFBD><C8AB><EFBFBD><EFBFBD><EFBFBD><EFBFBD> */
    j = length - end_length;
		
		/* <20><><EFBFBD><EFBFBD><EFBFBD>û<EFBFBD><C3BB><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʣ<EFBFBD>࣬<EFBFBD><E0A3AC><EFBFBD><EFBFBD>Ҫ<EFBFBD><D2AA>FIFO<46><4F><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ͷ<EFBFBD><CDB7><EFBFBD><EFBFBD>ʼ<EFBFBD><CABC><EFBFBD><EFBFBD>*/
    if ( j > 0 )
    {
        fifo_buffer = fifo->buffer;

        for( i = 0; i < j; i++ )
        {
            *( buffer++ ) = *( fifo_buffer++ ) ;
        }
    }
		
		/* <20><>¼<EFBFBD>ѳ<EFBFBD><D1B3>ӵij<D3B5><C4B3><EFBFBD> */
    fifo->out += length;
		
		/* <20><><EFBFBD><EFBFBD>FIFO<46><4F><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ݳ<EFBFBD><DDB3><EFBFBD>С<EFBFBD><D0A1><EFBFBD>û<EFBFBD>ʵ<EFBFBD><CAB5><EFBFBD><EFBFBD>Ҫ<EFBFBD><D2AA><EFBFBD>ݵij<DDB5><C4B3>ȣ<EFBFBD><C8A3>Ǿ<EFBFBD><C7BE><EFBFBD>FIFO<46><4F><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> */
    if( length < org_length )
    {
        return FIFO_ERROR_EMPTY;
    }
		
    return FIFO_OK;
}

fifo_error_t fifo_get_length( fifo_t *fifo , uint32_t *length)
{
		if( (fifo==0) || (length==0) )
		{
				return FIFO_ERROR_NULL;
		}
		
		*length = fifo->in - fifo->out;
	
    return FIFO_OK;
}

fifo_error_t fifo_get_remain_length( fifo_t *fifo , uint32_t *length)
{
		if( (fifo==0) || (length==0) )
		{
				return FIFO_ERROR_NULL;
		}	
	
    *length = fifo->size - ( fifo->in - fifo->out );
		
		return FIFO_OK;
}