lsquic_rechist.h revision b62ec17f 
1/* Copyright (c) 2017 - 2020 LiteSpeed Technologies Inc.  See LICENSE. */
2/*
3 * lsquic_rechist.h -- History of received packets.
4 *
5 * The purpose of received packet history is to generate ACK frames.
6 */
7
8#ifndef LSQUIC_RECHIST_H
9#define LSQUIC_RECHIST_H 1
10
11
12/* Structure is exposed to facilitate some manipulations in unit tests. */
13struct rechist_elem {
14    lsquic_packno_t     re_low;
15    unsigned            re_count;
16    unsigned            re_next;    /* UINT_MAX means no next element */
17};
18
19
20struct lsquic_rechist {
21    /* elems and masks are allocated in contiguous memory */
22    struct rechist_elem            *rh_elems;
23    uintptr_t                      *rh_masks;
24    lsquic_packno_t                 rh_cutoff;
25    lsquic_time_t                   rh_largest_acked_received;
26    unsigned                        rh_n_masks;
27    unsigned                        rh_n_alloced;
28    unsigned                        rh_n_used;
29    unsigned                        rh_head;
30    enum {
31        RH_CUTOFF_SET   = (1 << 0),
32    }                               rh_flags;
33    struct
34    {
35        struct lsquic_packno_range      range;
36        unsigned                        next;
37    }                               rh_iter;
38#if LSQUIC_TEST
39    unsigned                        rh_n_ops;
40#endif
41};
42
43typedef struct lsquic_rechist lsquic_rechist_t;
44
45void
46lsquic_rechist_init (struct lsquic_rechist *, int is_ietf);
47
48void
49lsquic_rechist_cleanup (struct lsquic_rechist *);
50
51enum received_st {
52    REC_ST_OK,
53    REC_ST_DUP,
54    REC_ST_ERR,
55};
56
57enum received_st
58lsquic_rechist_received (lsquic_rechist_t *, lsquic_packno_t,
59                         lsquic_time_t now);
60
61void
62lsquic_rechist_stop_wait (lsquic_rechist_t *, lsquic_packno_t);
63
64const struct lsquic_packno_range *
65lsquic_rechist_first (lsquic_rechist_t *);
66
67const struct lsquic_packno_range *
68lsquic_rechist_next (lsquic_rechist_t *);
69
70lsquic_packno_t
71lsquic_rechist_largest_packno (const lsquic_rechist_t *);
72
73lsquic_packno_t
74lsquic_rechist_cutoff (const lsquic_rechist_t *);
75
76lsquic_time_t
77lsquic_rechist_largest_recv (const lsquic_rechist_t *);
78
79size_t
80lsquic_rechist_mem_used (const struct lsquic_rechist *);
81
82const struct lsquic_packno_range *
83lsquic_rechist_peek (struct lsquic_rechist *);
84
85#define lsquic_rechist_is_empty(rechist_) ((rechist_)->rh_n_used == 0)
86
87#endif
88