This source file includes following definitions.
- timespec_sub
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24 #include <config.h>
25 #include "timespec.h"
26
27 #include "intprops.h"
28
29 struct timespec
30 timespec_sub (struct timespec a, struct timespec b)
31 {
32 time_t rs = a.tv_sec;
33 time_t bs = b.tv_sec;
34 int ns = a.tv_nsec - b.tv_nsec;
35 int rns = ns;
36
37 if (ns < 0)
38 {
39 rns = ns + TIMESPEC_HZ;
40 time_t bs1;
41 if (!INT_ADD_WRAPV (bs, 1, &bs1))
42 bs = bs1;
43 else if (- TYPE_SIGNED (time_t) < rs)
44 rs--;
45 else
46 goto low_overflow;
47 }
48
49 if (INT_SUBTRACT_WRAPV (rs, bs, &rs))
50 {
51 if (0 < bs)
52 {
53 low_overflow:
54 rs = TYPE_MINIMUM (time_t);
55 rns = 0;
56 }
57 else
58 {
59 rs = TYPE_MAXIMUM (time_t);
60 rns = TIMESPEC_HZ - 1;
61 }
62 }
63
64 return make_timespec (rs, rns);
65 }