Mercurial > hg > nginx
annotate src/http/v3/ngx_http_v3.c @ 8349:b13176e717ba quic
HTTP/3: fixed encoding variable-length integers.
| author | Roman Arutyunyan <arut@nginx.com> |
|---|---|
| date | Tue, 21 Apr 2020 17:11:49 +0300 |
| parents | 268f4389130d |
| children | b0e81f49d7c0 |
| rev | line source |
|---|---|
| 8215 | 1 |
| 2 /* | |
| 3 * Copyright (C) Roman Arutyunyan | |
| 4 * Copyright (C) Nginx, Inc. | |
| 5 */ | |
| 6 | |
| 7 | |
| 8 #include <ngx_config.h> | |
| 9 #include <ngx_core.h> | |
| 10 #include <ngx_http.h> | |
| 11 | |
| 12 | |
| 13 uintptr_t | |
| 14 ngx_http_v3_encode_varlen_int(u_char *p, uint64_t value) | |
| 15 { | |
| 16 if (value <= 63) { | |
| 17 if (p == NULL) { | |
| 18 return 1; | |
| 19 } | |
| 20 | |
| 21 *p++ = value; | |
| 22 return (uintptr_t) p; | |
| 23 } | |
| 24 | |
| 25 if (value <= 16383) { | |
| 26 if (p == NULL) { | |
| 27 return 2; | |
| 28 } | |
| 29 | |
| 30 *p++ = 0x40 | (value >> 8); | |
| 31 *p++ = value; | |
| 32 return (uintptr_t) p; | |
| 33 } | |
| 34 | |
| 35 if (value <= 1073741823) { | |
| 36 if (p == NULL) { | |
|
8349
b13176e717ba
HTTP/3: fixed encoding variable-length integers.
Roman Arutyunyan <arut@nginx.com>
parents:
8226
diff
changeset
|
37 return 4; |
| 8215 | 38 } |
| 39 | |
|
8349
b13176e717ba
HTTP/3: fixed encoding variable-length integers.
Roman Arutyunyan <arut@nginx.com>
parents:
8226
diff
changeset
|
40 *p++ = 0x80 | (value >> 24); |
|
b13176e717ba
HTTP/3: fixed encoding variable-length integers.
Roman Arutyunyan <arut@nginx.com>
parents:
8226
diff
changeset
|
41 *p++ = (value >> 16); |
| 8215 | 42 *p++ = (value >> 8); |
| 43 *p++ = value; | |
| 44 return (uintptr_t) p; | |
| 45 } | |
| 46 | |
| 47 if (p == NULL) { | |
|
8349
b13176e717ba
HTTP/3: fixed encoding variable-length integers.
Roman Arutyunyan <arut@nginx.com>
parents:
8226
diff
changeset
|
48 return 8; |
| 8215 | 49 } |
| 50 | |
|
8349
b13176e717ba
HTTP/3: fixed encoding variable-length integers.
Roman Arutyunyan <arut@nginx.com>
parents:
8226
diff
changeset
|
51 *p++ = 0xc0 | (value >> 56); |
|
b13176e717ba
HTTP/3: fixed encoding variable-length integers.
Roman Arutyunyan <arut@nginx.com>
parents:
8226
diff
changeset
|
52 *p++ = (value >> 48); |
|
b13176e717ba
HTTP/3: fixed encoding variable-length integers.
Roman Arutyunyan <arut@nginx.com>
parents:
8226
diff
changeset
|
53 *p++ = (value >> 40); |
|
b13176e717ba
HTTP/3: fixed encoding variable-length integers.
Roman Arutyunyan <arut@nginx.com>
parents:
8226
diff
changeset
|
54 *p++ = (value >> 32); |
|
b13176e717ba
HTTP/3: fixed encoding variable-length integers.
Roman Arutyunyan <arut@nginx.com>
parents:
8226
diff
changeset
|
55 *p++ = (value >> 24); |
| 8215 | 56 *p++ = (value >> 16); |
| 57 *p++ = (value >> 8); | |
| 58 *p++ = value; | |
| 59 return (uintptr_t) p; | |
| 60 } | |
| 61 | |
| 62 | |
| 63 uintptr_t | |
| 64 ngx_http_v3_encode_prefix_int(u_char *p, uint64_t value, ngx_uint_t prefix) | |
| 65 { | |
| 66 ngx_uint_t thresh, n; | |
| 67 | |
| 68 thresh = (1 << prefix) - 1; | |
| 69 | |
| 70 if (value < thresh) { | |
| 71 if (p == NULL) { | |
| 72 return 1; | |
| 73 } | |
| 74 | |
| 75 *p++ |= value; | |
| 76 return (uintptr_t) p; | |
| 77 } | |
| 78 | |
| 79 value -= thresh; | |
| 80 | |
| 81 for (n = 10; n > 1; n--) { | |
| 82 if (value >> (7 * (n - 1))) { | |
| 83 break; | |
| 84 } | |
| 85 } | |
| 86 | |
| 87 if (p == NULL) { | |
| 88 return n + 1; | |
| 89 } | |
| 90 | |
| 91 *p++ |= thresh; | |
| 92 | |
| 93 for ( /* void */ ; n > 1; n--) { | |
| 94 *p++ = 0x80 | (value >> 7 * (n - 1)); | |
| 95 } | |
| 96 | |
| 97 *p++ = value & 0x7f; | |
| 98 | |
| 99 return (uintptr_t) p; | |
| 100 } |