first-in first-out program

#include <xc.h>
#include "fifo.h"

#define FifoLength 32
unsigned char FifoBuffer[FifoLength];
unsigned char *FifoStart;
unsigned char *FifoEnd;
unsigned char count;


void InitFifo(void){
    FifoStart=FifoBuffer;
    FifoEnd=FifoBuffer;
    count=0;
}

void PutFifo(unsigned char chr){
    *FifoEnd++=chr;
    count++;
    if(FifoEnd==FifoBuffer+FifoLength)      //reached end
        FifoEnd=FifoBuffer;                 //yes so wrap
    if(count=FifoLength){                   //is head eating tail?
        //fifo full so deal with it!!
    }
}

unsigned char GetFifo(void){
unsigned char chr;
    while(FifoStart==FifoEnd);              //if fifo empty then wait
    chr=*FifoStart++;
    count--;
    if(FifoStart==FifoBuffer+FifoLength)    //wrapped?
        FifoStart=FifoBuffer;               //yes
    return(chr);
}

unsigned char FifoCount(void){
    return(count);
}