1 #include <geekos/ring_buffer.h>
2 #include <geekos/malloc.h>
3 #include <geekos/ktypes.h>
7 void init_ring_buffer(struct ring_buffer * ring, uint_t size) {
8 ring->buf = Malloc(size);
13 ring->current_len = 0;
17 struct ring_buffer * create_ring_buffer(uint_t size) {
18 struct ring_buffer * ring = (struct ring_buffer *)Malloc(sizeof(struct ring_buffer));
20 init_ring_buffer(ring, size);
25 void free_ring_buffer(struct ring_buffer * ring) {
34 static inline uchar_t * get_buf_ptr(struct ring_buffer * ring) {
35 return (uchar_t *)&(ring->buf + ring->start);
39 static inline int get_section_size(struct ring_buffer * ring) {
40 return ring->size - ring->start;
43 static inline int is_loop(struct ring_buffer * ring, uint_t len) {
44 if ((ring->start >= ring->end) && (ring->current_len > 0)) {
45 // end is past the end of the buffer
46 if (get_section_size(ring) < len) {
55 int rb_read(struct ring_buffer * ring, char * dst, uint_t len) {
57 int ring_data_len = ring->current_len;
59 read_len = (len > ring_data_len) ? ring_data_len : len;
61 if (is_loop(ring, read_len)) {
62 int first_len = get_section_size(ring);
64 memcpy(dst, get_buf_ptr(ring), first_len);
65 read_len -= first_len;
68 memcpy(dst + first_len, get_buf_ptr, read_len);
71 memcpy(dst, get_buf_ptr(ring), read_len);