EPSIAE » eneraptor

#include "buf.h"

#include <stdlib.h>

d_bufr *init_buf(int buf_size)

{

    printf("-----------------\n");

    printf("Creating buffer; size %d!\n", buf_size);

    d_bufr *buf;

    buf = (d_bufr *)malloc(sizeof(d_bufr));

    //*

    buf->buffer_size = buf_size;

    // TODO should allocate (element_t *) type instead of (int *)?

    // malloc(BUFFER_SIZE * sizeof (element_t));

    buf->elements = malloc(buf_size * sizeof (element_t));

    buf->start_p = &buf->elements;

    buf->start_el= &buf->elements;

    //buf->end_p = buf->start_p+buf->buffer_size-1;

    buf->end_p   = &buf->elements;

    buf->buffer_load = 0;

    /*

    // TODO just a bunch of tests for deletion

    //printf("buf addr: %d\n", buf);

    printf("buf start_p: %d\n", buf->start_p);

    //printf("buf &start_p: %d\n", &buf->start_p);

    //printf("buf *start_p: %d\n", *buf->start_p);

    printf("buf end_p: %d\n", buf->end_p);

    //printf("buf elements: %d\n", buf->elements);

    printf("buf &elements: %d\n", &buf->elements);

    //printf("buf size: %d\n", buf->buffer_size);

    //printf("buf load %d\n", buf->buffer_load);

    // TODO possilbe bug in buffer allocation! following sums should be the same

    // buf start_p + buffer_size - buf start_p should be 4 * buffer_size

    // in first case it is, but in second it is 2 times bigger!

    printf("buf start_p+buffer_size: %d\n", buf->start_p+buf_size);

    printf("&buf->elements+buf->buffer_size: %d\n", &buf->elements+buf->buffer_size);

    printf("sizeof(buf->elements) %d\n", sizeof(buf->elements));

    printf("sizeof(element_t) %d\n", sizeof(element_t));

    /**/

    return buf;

}

void increase_start_p(d_bufr *buf)

{

    /*

    printf("pre buf->start_p \t%d\n",buf->start_p);

    printf("pre buf->end_p \t\t%d\n",buf->end_p);

    printf("limit address \t\t%d\n", buf->start_el + buf->buffer_size);

    printf("-\n");

    /**/

    if((buf->start_p+1)!=(buf->start_el + buf->buffer_size)) // no loop

    {

        //pomakni se endp ce je isti naslov kot startp

        //printf("no loop\n");

        if((buf->start_p+1)==(buf->end_p))

        {

            //printf("lol fail\n");

            increase_end_p(buf);

        }

        else

        {

            //printf("ok zakon\n");

            buf->buffer_load++;

        }

        buf->start_p++;

    }

    else //loop

    {

        if(buf->end_p==buf->start_el)

            increase_end_p(buf);

        else

            buf->buffer_load++;

        buf->start_p = buf->start_el;

    }

    //printf("after buf->start_p \t%d\n",buf->start_p);

}

int increase_end_p(d_bufr *buf)

{

    //printf("pre buf->end_p \t\t%d\n",buf->end_p);

    if((buf->end_p+1)!=(buf->start_el + buf->buffer_size)) // no loop

    {

        if((buf->end_p+1)==(buf->start_p)) //buffer empty

            return 0;

        buf->end_p++;

    }

    else //loop

    {

        if(buf->start_p==buf->elements) //buffer empty

            return 0;

        buf->end_p = buf->elements;

    }

    //printf("after buf->end_p \t%d\n",buf->end_p);

    return 1;

}

void buf_put(element_t element, d_bufr *buf)

{

    *buf->start_p = element;

    increase_start_p(buf);

}

int buf_get(element_t *element, d_bufr *buf)

{

    *element = *buf->end_p;

    if(increase_end_p(buf)==1){

        buf->buffer_load--;

        return 1;

    }

    else //error

        return 0;

}

int get_buffer_load(d_bufr *buf)

{

    return buf->buffer_load;

}