1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
|
/*
*
* Copyright 2015 gRPC authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
#include <grpc/support/port_platform.h>
#include "src/core/lib/transport/timeout_encoding.h"
#include <stdio.h>
#include <string.h>
#include "src/core/lib/gpr/string.h"
static int64_t round_up(int64_t x, int64_t divisor) {
return (x / divisor + (x % divisor != 0)) * divisor;
}
/* round an integer up to the next value with three significant figures */
static int64_t round_up_to_three_sig_figs(int64_t x) {
if (x < 1000) return x;
if (x < 10000) return round_up(x, 10);
if (x < 100000) return round_up(x, 100);
if (x < 1000000) return round_up(x, 1000);
if (x < 10000000) return round_up(x, 10000);
if (x < 100000000) return round_up(x, 100000);
if (x < 1000000000) return round_up(x, 1000000);
return round_up(x, 10000000);
}
/* encode our minimum viable timeout value */
static void enc_tiny(char* buffer) { memcpy(buffer, "1n", 3); }
/* encode our maximum timeout value, about 1157 days */
static void enc_huge(char* buffer) { memcpy(buffer, "99999999S", 10); }
static void enc_ext(char* buffer, int64_t value, char ext) {
int n = int64_ttoa(value, buffer);
buffer[n] = ext;
buffer[n + 1] = 0;
}
static void enc_seconds(char* buffer, int64_t sec) {
sec = round_up_to_three_sig_figs(sec);
if (sec % 3600 == 0) {
enc_ext(buffer, sec / 3600, 'H');
} else if (sec % 60 == 0) {
enc_ext(buffer, sec / 60, 'M');
} else {
enc_ext(buffer, sec, 'S');
}
}
static void enc_millis(char* buffer, int64_t x) {
x = round_up_to_three_sig_figs(x);
if (x < GPR_MS_PER_SEC) {
enc_ext(buffer, x, 'm');
} else {
if (x % GPR_MS_PER_SEC == 0) {
enc_seconds(buffer, x / GPR_MS_PER_SEC);
} else {
enc_ext(buffer, x, 'm');
}
}
}
void grpc_http2_encode_timeout(grpc_millis timeout, char* buffer) {
const grpc_millis kMaxTimeout = 99999999000;
if (timeout <= 0) {
enc_tiny(buffer);
} else if (timeout < 1000 * GPR_MS_PER_SEC) {
enc_millis(buffer, timeout);
} else if (timeout >= kMaxTimeout) {
enc_huge(buffer);
} else {
enc_seconds(buffer,
timeout / GPR_MS_PER_SEC + (timeout % GPR_MS_PER_SEC != 0));
}
}
static int is_all_whitespace(const char* p, const char* end) {
while (p != end && *p == ' ') p++;
return p == end;
}
int grpc_http2_decode_timeout(const grpc_slice& text, grpc_millis* timeout) {
grpc_millis x = 0;
const uint8_t* p = GRPC_SLICE_START_PTR(text);
const uint8_t* end = GRPC_SLICE_END_PTR(text);
int have_digit = 0;
/* skip whitespace */
for (; p != end && *p == ' '; p++) {
}
/* decode numeric part */
for (; p != end && *p >= '0' && *p <= '9'; p++) {
int32_t digit = static_cast<int32_t>(*p - static_cast<uint8_t>('0'));
have_digit = 1;
/* spec allows max. 8 digits, but we allow values up to 1,000,000,000 */
if (x >= (100 * 1000 * 1000)) {
if (x != (100 * 1000 * 1000) || digit != 0) {
*timeout = GRPC_MILLIS_INF_FUTURE;
return 1;
}
}
x = x * 10 + digit;
}
if (!have_digit) return 0;
/* skip whitespace */
for (; p != end && *p == ' '; p++) {
}
if (p == end) return 0;
/* decode unit specifier */
switch (*p) {
case 'n':
*timeout = x / GPR_NS_PER_MS + (x % GPR_NS_PER_MS != 0);
break;
case 'u':
*timeout = x / GPR_US_PER_MS + (x % GPR_US_PER_MS != 0);
break;
case 'm':
*timeout = x;
break;
case 'S':
*timeout = x * GPR_MS_PER_SEC;
break;
case 'M':
*timeout = x * 60 * GPR_MS_PER_SEC;
break;
case 'H':
*timeout = x * 60 * 60 * GPR_MS_PER_SEC;
break;
default:
return 0;
}
p++;
return is_all_whitespace(reinterpret_cast<const char*>(p),
reinterpret_cast<const char*>(end));
}
|
