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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2021-07-23 11:29:01 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2021-07-23 11:37:28 +0000 |
commit | a7283ab143d4e95e8f5f22b58c61cb4e2f604749 (patch) | |
tree | 3ec5165ac7f1299f5c0dc3e41d7560a06e6267f5 /src/ck_ec_timeutil.h | |
parent | Adding debian version 0.6.0-2. (diff) | |
download | ck-a7283ab143d4e95e8f5f22b58c61cb4e2f604749.tar.xz ck-a7283ab143d4e95e8f5f22b58c61cb4e2f604749.zip |
Merging upstream version 0.7.1 (Closes: #991419).
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | src/ck_ec_timeutil.h | 150 |
1 files changed, 150 insertions, 0 deletions
diff --git a/src/ck_ec_timeutil.h b/src/ck_ec_timeutil.h new file mode 100644 index 0000000..50cfb67 --- /dev/null +++ b/src/ck_ec_timeutil.h @@ -0,0 +1,150 @@ +#ifndef CK_EC_TIMEUTIL_H +#define CK_EC_TIMEUTIL_H +#include <ck_cc.h> +#include <ck_ec.h> +#include <ck_limits.h> +#include <ck_stdint.h> +#include <sys/time.h> + +#define TIME_MAX ((time_t)((1ULL << ((sizeof(time_t) * CHAR_BIT) - 1)) - 1)) +#define NSEC_MAX ((1000L * 1000 * 1000) - 1) + +/* + * Approximates (nsec * multiplier) >> shift. Clamps to UINT32_MAX on + * overflow. + */ +CK_CC_UNUSED static uint32_t +wait_time_scale(uint32_t nsec, + uint32_t multiplier, + unsigned int shift) +{ + uint64_t temp = (uint64_t)nsec * multiplier; + uint64_t max = (uint64_t)UINT32_MAX << shift; + + if (temp >= max) { + return UINT32_MAX; + } + + return temp >> shift; +} + + +/* + * Returns ts + ns. ns is clamped to at most 1 second. Clamps the + * return value to TIME_MAX, NSEC_MAX on overflow. + * + */ +CK_CC_UNUSED static struct timespec timespec_add_ns(const struct timespec ts, + uint32_t ns) +{ + struct timespec ret = { + .tv_sec = TIME_MAX, + .tv_nsec = NSEC_MAX + }; + time_t sec; + uint32_t sum_ns; + + if (ns > (uint32_t)NSEC_MAX) { + if (ts.tv_sec >= TIME_MAX) { + return ret; + } + + ret.tv_sec = ts.tv_sec + 1; + ret.tv_nsec = ts.tv_nsec; + return ret; + } + + sec = ts.tv_sec; + sum_ns = ns + ts.tv_nsec; + if (sum_ns > NSEC_MAX) { + if (sec >= TIME_MAX) { + return ret; + } + + sec++; + sum_ns -= (NSEC_MAX + 1); + } + + ret.tv_sec = sec; + ret.tv_nsec = sum_ns; + return ret; +} + + +/* + * Returns ts + inc. If inc is negative, it is normalized to 0. + * Clamps the return value to TIME_MAX, NSEC_MAX on overflow. + */ +CK_CC_UNUSED static struct timespec timespec_add(const struct timespec ts, + const struct timespec inc) +{ + /* Initial return value is clamped to infinite future. */ + struct timespec ret = { + .tv_sec = TIME_MAX, + .tv_nsec = NSEC_MAX + }; + time_t sec; + unsigned long nsec; + + /* Non-positive delta is a no-op. Invalid nsec is another no-op. */ + if (inc.tv_sec < 0 || inc.tv_nsec < 0 || inc.tv_nsec > NSEC_MAX) { + return ts; + } + + /* Detect overflow early. */ + if (inc.tv_sec > TIME_MAX - ts.tv_sec) { + return ret; + } + + sec = ts.tv_sec + inc.tv_sec; + /* This sum can't overflow if the inputs are valid.*/ + nsec = (unsigned long)ts.tv_nsec + inc.tv_nsec; + + if (nsec > NSEC_MAX) { + if (sec >= TIME_MAX) { + return ret; + } + + sec++; + nsec -= (NSEC_MAX + 1); + } + + ret.tv_sec = sec; + ret.tv_nsec = nsec; + return ret; +} + +/* Compares two timespecs. Returns -1 if x < y, 0 if x == y, and 1 if x > y. */ +CK_CC_UNUSED static int timespec_cmp(const struct timespec x, + const struct timespec y) +{ + if (x.tv_sec != y.tv_sec) { + return (x.tv_sec < y.tv_sec) ? -1 : 1; + } + + if (x.tv_nsec != y.tv_nsec) { + return (x.tv_nsec < y.tv_nsec) ? -1 : 1; + } + + return 0; +} + +/* + * Overwrites now with the current CLOCK_MONOTONIC time, and returns + * true if the current time is greater than or equal to the deadline, + * or the clock is somehow broken. + */ +CK_CC_UNUSED static bool check_deadline(struct timespec *now, + const struct ck_ec_ops *ops, + const struct timespec deadline) +{ + int r; + + r = ops->gettime(ops, now); + if (r != 0) { + return true; + } + + return timespec_cmp(*now, deadline) >= 0; +} +#endif /* !CK_EC_TIMEUTIL_H */ |