xref: /aosp_15_r20/external/llvm-libc/include/llvm-libc-macros/linux/sys-time-macros.h (revision 71db0c75aadcf003ffe3238005f61d7618a3fead)
1 //===-- Definition of macros from sys/time.h ------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #ifndef LLVM_LIBC_MACROS_LINUX_SYS_TIME_MACROS_H
10 #define LLVM_LIBC_MACROS_LINUX_SYS_TIME_MACROS_H
11 
12 // Add two timevals and put the result in timeval_ptr_result. If the resulting
13 // usec value is greater than 999,999 then the microseconds are turned into full
14 // seconds (1,000,000 is subtracted from usec and 1 is added to sec).
15 #define timeradd(timeval_ptr_a, timeval_ptr_b, timeval_ptr_result)             \
16   (timeval_ptr_result)->tv_sec =                                               \
17       (timeval_ptr_a)->tv_sec + (timeval_ptr_b)->tv_sec +                      \
18       (((timeval_ptr_a)->tv_usec + (timeval_ptr_b)->tv_usec) >= 1000000 ? 1    \
19                                                                         : 0);  \
20   (timeval_ptr_result)->tv_usec =                                              \
21       (timeval_ptr_a)->tv_usec + (timeval_ptr_b)->tv_usec -                    \
22       (((timeval_ptr_a)->tv_usec + (timeval_ptr_b)->tv_usec) >= 1000000        \
23            ? 1000000                                                           \
24            : 0);
25 
26 // Subtract two timevals and put the result in timeval_ptr_result. If the
27 // resulting usec value is less than 0 then 1,000,000 is added to usec and 1 is
28 // subtracted from sec.
29 #define timersub(timeval_ptr_a, timeval_ptr_b, timeval_ptr_result)             \
30   (timeval_ptr_result)->tv_sec =                                               \
31       (timeval_ptr_a)->tv_sec - (timeval_ptr_b)->tv_sec -                      \
32       (((timeval_ptr_a)->tv_usec - (timeval_ptr_b)->tv_usec) < 0 ? 1 : 0);     \
33   (timeval_ptr_result)->tv_usec =                                              \
34       (timeval_ptr_a)->tv_usec - (timeval_ptr_b)->tv_usec +                    \
35       (((timeval_ptr_a)->tv_usec - (timeval_ptr_b)->tv_usec) < 0 ? 1000000     \
36                                                                  : 0);
37 
38 // Reset a timeval to the epoch.
39 #define timerclear(timeval_ptr)                                                \
40   (timeval_ptr)->tv_sec = 0;                                                   \
41   (timeval_ptr)->tv_usec = 0;
42 
43 // Determine if a timeval is set to the epoch.
44 #define timerisset(timeval_ptr)                                                \
45   (timeval_ptr)->tv_sec != 0 || (timeval_ptr)->tv_usec != 0;
46 
47 // Compare two timevals using CMP.
48 #define timercmp(timeval_ptr_a, timeval_ptr_b, CMP)                            \
49   (((timeval_ptr_a)->tv_sec == (timeval_ptr_b)->tv_sec)                        \
50        ? ((timeval_ptr_a)->tv_usec CMP(timeval_ptr_b)->tv_usec)                \
51        : ((timeval_ptr_a)->tv_sec CMP(timeval_ptr_b)->tv_sec))
52 
53 #endif // LLVM_LIBC_MACROS_LINUX_SYS_TIME_MACROS_H
54