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/* ==========================================================================
* Licensed under BSD 2clause license See LICENSE file for more information
* Author: Michał Łyszczek <michal.lyszczek@bofc.pl>
* ========================================================================== */
#include <string.h>
#include <stdio.h>
#include "rb.h"
#include "common.h"
#define STACK_ALLOCATION 1
int main(void)
{
#if STACK_ALLOCATION
struct rb rbs; /* stack allocated ring buffer object */
int buffer[128]; /* buffer to hold 128 integers */
#endif
struct rb *rb; /* pointer to new rb object */
long nwritten; /* return value from rb_write() */
long nread; /* return value from rb_read() */
int data_to_write[256]; /* data to write into rb buffer */
int data_read[256]; /* buffer where we will read from rb */
/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
/* You can use stack or heap allocations. Pick your poison. */
#if STACK_ALLOCATION
/* Initialize stack allocated #rb. Use stack allocated #buffer to
* hold data. Tell #rb array properties that is length and single
* element size */
if (rb_init(&rbs, buffer, rb_array_size(buffer), sizeof(int), 0))
pdie("rb_init()");
rb = &rbs;
#else
/* Initialize ring buffer using heap. Buffer of #rb it allocated
* internally as well */
if ((rb = rb_new(128, sizeof(int), 0)) == NULL)
pdie("rb_init()");
#endif
/* fill data to send with some data */
for (int i = 0; i != rb_array_size(data_to_write); ++i)
data_to_write[i] = i;
/* put data in the buffer, buffer can hold only 127 elements, and we try
* to put 256 integers (elements) there, so rb_write will return 127,
* as this is number of elements copied to rb object. */
nwritten = rb_write(rb, data_to_write, rb_array_size(data_to_write));
printf("number of elements stored to rb: %ld\n", nwritten);
/* buffer is now full, any write to it will result in error */
if (rb_write(rb, data_read, 1) == -1)
perror("rb_write() returned error");
/* now we read maximum of 256 elements from rb to data_read buffer, but
* since we put 127 elements in rb, only 127 elements will be copied
* back to #data_read */
memset(data_read, 0x00, sizeof(data_read));
nread = rb_read(rb, data_read, rb_array_size(data_read));
printf("number of elements read from rb: %ld\n", nread);
/* buffer is now empty, any read from it will result in error */
if (rb_read(rb, data_read, 1) == -1)
perror("rb_write() returned error");
/* check if data read matches what we've just put on buffer */
printf("Checking if data matches... data %s\n",
memcmp(data_read, data_to_write, nread * sizeof(int)) ? "not ok" : "ok");
/* don't forget to cleanup object when done. */
#if STACK_ALLOCATION
rb_cleanup(rb);
#else
rb_destroy(rb);
#endif
return 0;
}
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