lsquic_senhist.h revision bfc7bfd8 
1/* Copyright (c) 2017 LiteSpeed Technologies Inc.  See LICENSE. */
2/*
3 * lsquic_senhist.h -- History sent packets.
4 *
5 * We only keep track of packet numbers in order to verify ACKs.
6 */
7
8#ifndef LSQUIC_SENHIST_H
9#define LSQUIC_SENHIST_H 1
10
11#include "lsquic_packints.h"
12
13typedef struct lsquic_senhist {
14    /* These ranges are ordered from high to low.  While searching this
15     * structure is O(n), I expect that in practice, a very long search
16     * could only happen once before the connection is terminated,
17     * because:
18     *  a) either the packet number far away is real, but it was so long
19     *     ago that it would have timed out by now (RTO); or
20     *  b) the peer sends an invalid ACK.
21     */
22    struct packints             sh_pints;
23} lsquic_senhist_t;
24
25void
26lsquic_senhist_init (lsquic_senhist_t *);
27
28void
29lsquic_senhist_cleanup (lsquic_senhist_t *);
30
31int
32lsquic_senhist_add (lsquic_senhist_t *, lsquic_packno_t);
33
34/* Returns true if history contains all packets numbers in this range.
35 */
36int
37lsquic_senhist_sent_range (lsquic_senhist_t *, lsquic_packno_t low,
38                                               lsquic_packno_t high);
39
40/* Returns 0 if no packets have been sent yet */
41lsquic_packno_t
42lsquic_senhist_largest (lsquic_senhist_t *hist);
43
44void
45lsquic_senhist_tostr (lsquic_senhist_t *hist, char *buf, size_t bufsz);
46
47size_t
48lsquic_senhist_mem_used (const struct lsquic_senhist *);
49
50#endif
51