1 | #ifndef AWS_COMMON_CLOCK_INL |
2 | #define AWS_COMMON_CLOCK_INL |
3 | |
4 | /* |
5 | * Copyright 2010-2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. |
6 | * |
7 | * Licensed under the Apache License, Version 2.0 (the "License"). |
8 | * You may not use this file except in compliance with the License. |
9 | * A copy of the License is located at |
10 | * |
11 | * http://aws.amazon.com/apache2.0 |
12 | * |
13 | * or in the "license" file accompanying this file. This file is distributed |
14 | * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either |
15 | * express or implied. See the License for the specific language governing |
16 | * permissions and limitations under the License. |
17 | */ |
18 | |
19 | #include <aws/common/clock.h> |
20 | #include <aws/common/common.h> |
21 | #include <aws/common/math.h> |
22 | |
23 | AWS_EXTERN_C_BEGIN |
24 | |
25 | /** |
26 | * Converts 'timestamp' from unit 'convert_from' to unit 'convert_to', if the units are the same then 'timestamp' is |
27 | * returned. If 'remainder' is NOT NULL, it will be set to the remainder if convert_from is a more precise unit than |
28 | * convert_to. To avoid unnecessary branching, 'remainder' is not zero initialized in this function, be sure to set it |
29 | * to 0 first if you care about that kind of thing. If conversion would lead to integer overflow, the timestamp |
30 | * returned will be the highest possible time that is representable, i.e. UINT64_MAX. |
31 | */ |
32 | AWS_STATIC_IMPL uint64_t aws_timestamp_convert( |
33 | uint64_t timestamp, |
34 | enum aws_timestamp_unit convert_from, |
35 | enum aws_timestamp_unit convert_to, |
36 | uint64_t *remainder) { |
37 | uint64_t diff = 0; |
38 | |
39 | if (convert_to > convert_from) { |
40 | diff = convert_to / convert_from; |
41 | return aws_mul_u64_saturating(timestamp, diff); |
42 | } else if (convert_to < convert_from) { |
43 | diff = convert_from / convert_to; |
44 | |
45 | if (remainder) { |
46 | *remainder = timestamp % diff; |
47 | } |
48 | |
49 | return timestamp / diff; |
50 | } else { |
51 | return timestamp; |
52 | } |
53 | } |
54 | |
55 | AWS_EXTERN_C_END |
56 | |
57 | #endif /* AWS_COMMON_CLOCK_INL */ |
58 | |