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#include <ring_buffer.h>
#include <alloc.h>
#include <misc_lib.h>
struct RingBuffer_
{
void *(*copy)(const void *data);
void (*destroy)(void *data);
void **data;
size_t capacity;
size_t end;
size_t len;
};
struct RingBufferIterator_
{
const RingBuffer *buf;
size_t num_read;
};
RingBuffer *RingBufferNew(size_t capacity, void *(*copy)(const void *), void (*destroy)(void *))
{
assert(capacity > 0);
RingBuffer *buf = xmalloc(sizeof(RingBuffer));
buf->copy = copy;
buf->destroy = destroy;
buf->data = xcalloc(capacity, sizeof(void *));
buf->capacity = MAX(capacity, 1);
buf->len = 0;
buf->end = 0;
return buf;
}
void RingBufferAppend(RingBuffer *buf, void *item)
{
if (buf->data[buf->end] && buf->destroy)
{
buf->destroy(buf->data[buf->end]);
}
buf->data[buf->end] = buf->copy ? buf->copy(item) : item;
buf->end = (buf->end + 1) % buf->capacity;
if (buf->len < buf->capacity)
{
buf->len++;
}
}
void RingBufferClear(RingBuffer *buf)
{
if (buf->destroy)
{
for (size_t i = 0; i < buf->capacity; i++)
{
if (buf->data[i])
{
buf->destroy(buf->data[i]);
buf->data[i] = NULL;
}
}
}
buf->end = 0;
buf->len = 0;
}
size_t RingBufferLength(const RingBuffer *buf)
{
return buf->len;
}
bool RingBufferIsFull(const RingBuffer *buf)
{
return buf->len == buf->capacity;
}
const void *RingBufferHead(const RingBuffer *buf)
{
if (RingBufferLength(buf) == 0)
{
return NULL;
}
if (buf->end == 0)
{
return buf->data[buf->capacity - 1];
}
else
{
return buf->data[buf->end - 1];
}
}
RingBufferIterator *RingBufferIteratorNew(const RingBuffer *buf)
{
RingBufferIterator *iter = xmalloc(sizeof(RingBufferIterator));
iter->buf = buf;
iter->num_read = 0;
return iter;
}
void RingBufferDestroy(RingBuffer *buf)
{
if (buf)
{
RingBufferClear(buf);
free(buf->data);
free(buf);
}
}
void RingBufferIteratorDestroy(RingBufferIterator *iter)
{
if (iter)
{
free(iter);
}
}
const void *RingBufferIteratorNext(RingBufferIterator *iter)
{
if ((iter->buf->len - iter->num_read) == 0)
{
return NULL;
}
size_t offset = iter->num_read;
if (RingBufferIsFull(iter->buf))
{
offset = (iter->buf->end + iter->num_read) % iter->buf->capacity;
}
const void *data = iter->buf->data[offset];
iter->num_read++;
return data;
}
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