34 lines
693 B
C
34 lines
693 B
C
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#include <lib/ringbuf.h>
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void ring_buf_init(ring_buf_t* rb) {
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rb->head = 0;
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rb->tail = 0;
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}
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int ring_buf_is_empty(ring_buf_t* rb) {
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return rb->head == rb->tail;
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}
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int ring_buf_is_full(ring_buf_t* rb) {
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return ((rb->head + 1) % PTY_BUFFER_SIZE) == rb->tail;
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}
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int ring_buf_write(ring_buf_t *buf, char c) {
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if (ring_buf_is_full(buf)) {
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return -1;
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}
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buf->data[buf->head] = c;
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buf->head = (buf->head + 1) % PTY_BUFFER_SIZE;
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return 0;
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}
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int ring_buf_read(ring_buf_t *buf, char *c) {
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if (ring_buf_is_empty(buf)) {
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return -1;
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}
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*c = buf->data[buf->tail];
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buf->tail = (buf->tail + 1) % PTY_BUFFER_SIZE;
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return 0;
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}
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