1/* Copyright (c) 2017 - 2022 LiteSpeed Technologies Inc.  See LICENSE. */
2/*
3 * lsquic_hcsi_reader.h -- HTTP Control Stream Incoming (HCSI) reader
4 */
5
6#ifndef LSQUIC_HCSI_READER_H
7#define LSQUIC_HCSI_READER_H 1
8
9struct lsquic_conn;
10
11
12struct hcsi_callbacks
13{
14    void    (*on_cancel_push)(void *ctx, uint64_t push_id);
15    void    (*on_max_push_id)(void *ctx, uint64_t push_id);
16    /* Gets called at the *end* of the SETTING frame */
17    void    (*on_settings_frame)(void *ctx);
18    void    (*on_setting)(void *ctx, uint64_t setting_id, uint64_t value);
19    void    (*on_goaway)(void *ctx, uint64_t stream_id);
20    void    (*on_frame_error)(void *ctx, unsigned code, uint64_t frame_type);
21    void    (*on_priority_update)(void *ctx, enum hq_frame_type, uint64_t id,
22                                                        const char *, size_t);
23};
24
25
26struct hcsi_reader
27{
28    enum {
29        HR_READ_FRAME_BEGIN,
30        HR_READ_FRAME_CONTINUE,
31        HR_SKIPPING,
32        HR_READ_SETTING_BEGIN,
33        HR_READ_SETTING_CONTINUE,
34        HR_READ_PRIORITY_UPDATE,
35        HR_READ_VARINT,
36        HR_READ_VARINT_CONTINUE,
37        HR_ERROR,
38    }                               hr_state:8;
39    enum {
40        HR_FLAG_RCVD_SETTING = 1,
41    }                               hr_flag:8;
42    unsigned                        hr_nread;  /* Used for PRIORITY_UPDATE and SETTINGS frames */
43    struct lsquic_conn             *hr_conn;
44    uint64_t                        hr_frame_type;
45    uint64_t                        hr_frame_length;
46    union
47    {
48        struct varint_read_state            vint_state;
49        struct varint_read2_state           vint2_state;
50        struct {
51            /* We just need the offset to rest of prio_state to read Priority
52             * Field Value.
53             */
54            struct varint_read_state        UNUSED;
55            char                            buf[
56                        sizeof(struct varint_read2_state)
57                                - sizeof(struct varint_read_state)];
58        }                                   prio_state;
59    }                               hr_u;
60    const struct hcsi_callbacks    *hr_cb;
61    void                           *hr_ctx;
62};
63
64
65void
66lsquic_hcsi_reader_init (struct hcsi_reader *, struct lsquic_conn *,
67                                const struct hcsi_callbacks *, void *cb_ctx);
68
69int
70lsquic_hcsi_reader_feed (struct hcsi_reader *, const void *buf, size_t bufsz);
71
72#endif
73