unsigned char *sg_bip_buf_get(const sg_bip_buf_t *buf, const unsigned int size)
{
struct sg_bip_buf_real *me = (struct sg_bip_buf_real *)buf;
if (sg_bip_buf_is_empty(buf))
return NULL;
/* make sure we can actually poll this buf */
if (me->buf_size < me->a_start + size)
return NULL;
void *end = me->buf + me->a_start;
me->a_start += size;
/* we seem to be empty.. */
if (me->a_start == me->a_end) {
/* replace a with region b */
if (1 == me->b_inuse) {
me->a_start = 0;
me->a_end = me->b_end;
me->b_end = me->b_inuse = 0;
} else
/* safely move cursor back to the start because we are empty */
me->a_start = me->a_end = 0;
}
__check_for_switch_to_b(me);
return end;
}
unsigned char *bipbuf_poll(bipbuf_t* me, const unsigned int size)
{
if (bipbuf_is_empty(me))
return NULL;
/* make sure we can actually poll this data */
if (me->size < me->a_start + size)
return NULL;
void *end = me->data + me->a_start;
me->a_start += size;
/* we seem to be empty.. */
if (me->a_start == me->a_end)
{
/* replace a with region b */
if (1 == me->b_inuse)
{
me->a_start = 0;
me->a_end = me->b_end;
me->b_end = me->b_inuse = 0;
}
else
/* safely move cursor back to the start because we are empty */
me->a_start = me->a_end = 0;
}
__check_for_switch_to_b(me);
return end;
}
int bipbuf_push(bipbuf_t* me, const int size)
{
if (bipbuf_unused(me) < size)
return 0;
if (1 == me->b_inuse)
{
me->b_end += size;
}
else
{
me->a_end += size;
}
__check_for_switch_to_b(me);
return size;
}
int sg_bip_buf_put(const sg_bip_buf_t *buf, const unsigned char *data, const int size)
{
struct sg_bip_buf_real *me = (struct sg_bip_buf_real *)buf;
/* not enough space */
if (sg_bip_buf_unused_size(buf) < size)
return 0;
if (1 == me->b_inuse) {
memcpy(me->buf + me->b_end, data, size);
me->b_end += size;
} else {
memcpy(me->buf + me->a_end, data, size);
me->a_end += size;
}
__check_for_switch_to_b(me);
return size;
}
int bipbuf_offer(bipbuf_t* me, const unsigned char *data, const int size)
{
/* not enough space */
if (bipbuf_unused(me) < size)
return 0;
if (1 == me->b_inuse)
{
memcpy(me->data + me->b_end, data, size);
me->b_end += size;
}
else
{
memcpy(me->data + me->a_end, data, size);
me->a_end += size;
}
__check_for_switch_to_b(me);
return size;
}
