I am writing a circular/ring buffer of a specified size. I am struggling with figuring out if my code is working. It compiles and runs with no problem, but I try testing it with print statements and I get confused. Can anyone give me some advice for how to test that my code is functioning properly - access up to a defined number of buffers and checks if the buffer is full or empty when requesting the next and freeing the last buffer.
#include <stdio.h>
int head = 0;
int tail = 0;
int num_allocated = 0;
struct s_buffer
{
int dummy_val1;
int dummy_val2;
};
struct s_buffer ring[16];
int increment_head()
{
if (head >= 16)
{
head =0;
num_allocated ++;
}
else
{
head ++;
num_allocated ++;
}
return head;
}
int increment_tail()
{
if (tail >= 16)
{
tail =0;
num_allocated --;
}
else
{
tail ++;
num_allocated --;
}
return tail;
}
struct s_buffer* requestNextBuffer()
{
if(isBufferFull(tail))
{
return NULL;
}
else
{
struct s_buffer* sb = NULL;
increment_head();
sb = &ring[head];
return sb;
}
}
struct s_buffer* freeLastBuffer()
{
if(isBufferEmpty(head))
{
return NULL;
}
else
{
struct s_buffer* sb = NULL;
increment_tail();
sb = &ring[tail];
return sb;
}
}
int isBufferEmpty (int increment_head)
{
if (increment_head <=0)
{
return 1;
}
else
{
return 0;
}
}
int isBufferFull (int tail)
{
if (head==tail)
{
return 1;
}
else
{
return 0;
}
}
int main (void)
{
struct s_buffer *sb;
do
{
sb=requestNextBuffer();
sb->dummy_val1==2;
}
while (sb!=NULL);
}
