1 /* Support code for timespec checks.
2    Copyright (C) 2019-2022 Free Software Foundation, Inc.
3    This file is part of the GNU C Library.
4 
5    The GNU C Library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Lesser General Public
7    License as published by the Free Software Foundation; either
8    version 2.1 of the License, or (at your option) any later version.
9 
10    The GNU C Library is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13    Lesser General Public License for more details.
14 
15    You should have received a copy of the GNU Lesser General Public
16    License along with the GNU C Library; if not, see
17    <https://www.gnu.org/licenses/>.  */
18 
19 #include <support/timespec.h>
20 #include <stdio.h>
21 #include <stdint.h>
22 #include <assert.h>
23 #include <intprops.h>
24 
25 void
test_timespec_before_impl(const char * file,int line,struct timespec left,struct timespec right)26 test_timespec_before_impl (const char *file, int line, struct timespec left,
27 			   struct timespec right)
28 {
29   if (left.tv_sec > right.tv_sec
30       || (left.tv_sec == right.tv_sec
31 	  && left.tv_nsec > right.tv_nsec)) {
32     support_record_failure ();
33     const struct timespec diff = timespec_sub (left, right);
34     printf ("%s:%d: %jd.%09jds not before %jd.%09jds "
35 	    "(difference %jd.%09jds)\n",
36 	    file, line,
37 	    (intmax_t) left.tv_sec, (intmax_t) left.tv_nsec,
38 	    (intmax_t) right.tv_sec, (intmax_t) right.tv_nsec,
39 	    (intmax_t) diff.tv_sec, (intmax_t) diff.tv_nsec);
40   }
41 }
42 
43 void
test_timespec_equal_or_after_impl(const char * file,int line,struct timespec left,struct timespec right)44 test_timespec_equal_or_after_impl (const char *file, int line,
45 				   struct timespec left,
46 				   struct timespec right)
47 {
48   if (left.tv_sec < right.tv_sec
49       || (left.tv_sec == right.tv_sec
50 	  && left.tv_nsec < right.tv_nsec)) {
51     support_record_failure ();
52     const struct timespec diff = timespec_sub (right, left);
53     printf ("%s:%d: %jd.%09jds not after %jd.%09jds "
54 	    "(difference %jd.%09jds)\n",
55 	    file, line,
56 	    (intmax_t) left.tv_sec, (intmax_t) left.tv_nsec,
57 	    (intmax_t) right.tv_sec, (intmax_t) right.tv_nsec,
58 	    (intmax_t) diff.tv_sec, (intmax_t) diff.tv_nsec);
59   }
60 }
61 
62 /* Convert TIME to nanoseconds stored in a time_t.
63    Returns time_t maximum or minimum if the conversion overflows
64    or underflows, respectively.  */
65 time_t
support_timespec_ns(struct timespec time)66 support_timespec_ns (struct timespec time)
67 {
68   time_t time_ns;
69   if (INT_MULTIPLY_WRAPV(time.tv_sec, TIMESPEC_HZ, &time_ns))
70     return time.tv_sec < 0 ? TYPE_MINIMUM(time_t) : TYPE_MAXIMUM(time_t);
71   if (INT_ADD_WRAPV(time_ns, time.tv_nsec, &time_ns))
72     return time.tv_nsec < 0 ? TYPE_MINIMUM(time_t) : TYPE_MAXIMUM(time_t);
73   return time_ns;
74 }
75 
76 /* Returns time normalized timespec with .tv_nsec < TIMESPEC_HZ
77    and the whole seconds  added to .tv_sec. If an overflow or
78    underflow occurs the values are clamped to its maximum or
79    minimum respectively.  */
80 struct timespec
support_timespec_normalize(struct timespec time)81 support_timespec_normalize (struct timespec time)
82 {
83   struct timespec norm;
84   if (INT_ADD_WRAPV (time.tv_sec, (time.tv_nsec / TIMESPEC_HZ), &norm.tv_sec))
85    {
86      norm.tv_sec = (time.tv_nsec < 0) ? TYPE_MINIMUM (time_t): TYPE_MAXIMUM (time_t);
87      norm.tv_nsec = (time.tv_nsec < 0) ? -1 * (TIMESPEC_HZ - 1) : TIMESPEC_HZ - 1;
88      return norm;
89    }
90   norm.tv_nsec = time.tv_nsec % TIMESPEC_HZ;
91   return norm;
92 }
93 
94 /* Returns TRUE if the observed time is within the given percentage
95    bounds of the expected time, and FALSE otherwise.
96    For example the call
97 
98    support_timespec_check_in_range(expected, observed, 0.5, 1.2);
99 
100    will check if
101 
102    0.5 of expected <= observed <= 1.2 of expected
103 
104    In other words it will check if observed time is within 50% to
105    120% of the expected time.  */
106 int
support_timespec_check_in_range(struct timespec expected,struct timespec observed,double lower_bound,double upper_bound)107 support_timespec_check_in_range (struct timespec expected, struct timespec observed,
108 			      double lower_bound, double upper_bound)
109 {
110   assert (upper_bound >= lower_bound);
111   time_t expected_norm, observed_norm;
112   expected_norm = support_timespec_ns (expected);
113   /* Don't divide by zero  */
114   assert(expected_norm != 0);
115   observed_norm = support_timespec_ns (observed);
116   double ratio = (double)observed_norm / expected_norm;
117   return (lower_bound <= ratio && ratio <= upper_bound);
118 }
119