From fe624c4c07026fe11f37b7517e81b3814fa868bc Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Mon, 30 May 2016 22:08:21 +0200 Subject: time-util: add triple timestamp object We already have a double timestamp object that we use whenever we need both a MONOTONIC and a REALTIME timestamp taken and stored. With this change we also add a triple timestamp object that in addition stores a BOOTTIME timestamp, which is useful for a few usecases. Note that we keep dual_timestamp around, as it is useful in many cases where triple_timestamp is not, in particular because retrieving the monotonic and realtime timestamps is much cheaper on Linux that getting the boottime timestamp. --- src/basic/time-util.c | 72 +++++++++++++++++++++++++++++++++++++++++++++++++++ src/basic/time-util.h | 27 ++++++++++++++++++- 2 files changed, 98 insertions(+), 1 deletion(-) diff --git a/src/basic/time-util.c b/src/basic/time-util.c index edd9179cb8..24e681bf85 100644 --- a/src/basic/time-util.c +++ b/src/basic/time-util.c @@ -87,6 +87,16 @@ dual_timestamp* dual_timestamp_get(dual_timestamp *ts) { return ts; } +triple_timestamp* triple_timestamp_get(triple_timestamp *ts) { + assert(ts); + + ts->realtime = now(CLOCK_REALTIME); + ts->monotonic = now(CLOCK_MONOTONIC); + ts->boottime = clock_boottime_supported() ? now(CLOCK_BOOTTIME) : USEC_INFINITY; + + return ts; +} + dual_timestamp* dual_timestamp_from_realtime(dual_timestamp *ts, usec_t u) { int64_t delta; assert(ts); @@ -104,6 +114,24 @@ dual_timestamp* dual_timestamp_from_realtime(dual_timestamp *ts, usec_t u) { return ts; } +triple_timestamp* triple_timestamp_from_realtime(triple_timestamp *ts, usec_t u) { + int64_t delta; + + assert(ts); + + if (u == USEC_INFINITY || u <= 0) { + ts->realtime = ts->monotonic = ts->boottime = u; + return ts; + } + + ts->realtime = u; + delta = (int64_t) now(CLOCK_REALTIME) - (int64_t) u; + ts->monotonic = usec_sub(now(CLOCK_MONOTONIC), delta); + ts->boottime = clock_boottime_supported() ? usec_sub(now(CLOCK_BOOTTIME), delta) : USEC_INFINITY; + + return ts; +} + dual_timestamp* dual_timestamp_from_monotonic(dual_timestamp *ts, usec_t u) { int64_t delta; assert(ts); @@ -136,6 +164,26 @@ dual_timestamp* dual_timestamp_from_boottime_or_monotonic(dual_timestamp *ts, us return ts; } +usec_t triple_timestamp_by_clock(triple_timestamp *ts, clockid_t clock) { + + switch (clock) { + + case CLOCK_REALTIME: + case CLOCK_REALTIME_ALARM: + return ts->realtime; + + case CLOCK_MONOTONIC: + return ts->monotonic; + + case CLOCK_BOOTTIME: + case CLOCK_BOOTTIME_ALARM: + return ts->boottime; + + default: + return USEC_INFINITY; + } +} + usec_t timespec_load(const struct timespec *ts) { assert(ts); @@ -1107,6 +1155,30 @@ clockid_t clock_boottime_or_monotonic(void) { return CLOCK_MONOTONIC; } +bool clock_supported(clockid_t clock) { + struct timespec ts; + + switch (clock) { + + case CLOCK_MONOTONIC: + case CLOCK_REALTIME: + return true; + + case CLOCK_BOOTTIME: + return clock_boottime_supported(); + + case CLOCK_BOOTTIME_ALARM: + if (!clock_boottime_supported()) + return false; + + /* fall through, after checking the cached value for CLOCK_BOOTTIME. */ + + default: + /* For everything else, check properly */ + return clock_gettime(clock, &ts) >= 0; + } +} + int get_timezone(char **tz) { _cleanup_free_ char *t = NULL; const char *e; diff --git a/src/basic/time-util.h b/src/basic/time-util.h index a5e3f567ec..1b058f0e49 100644 --- a/src/basic/time-util.h +++ b/src/basic/time-util.h @@ -39,6 +39,12 @@ typedef struct dual_timestamp { usec_t monotonic; } dual_timestamp; +typedef struct triple_timestamp { + usec_t realtime; + usec_t monotonic; + usec_t boottime; +} triple_timestamp; + #define USEC_INFINITY ((usec_t) -1) #define NSEC_INFINITY ((nsec_t) -1) @@ -69,7 +75,8 @@ typedef struct dual_timestamp { #define TIME_T_MAX (time_t)((UINTMAX_C(1) << ((sizeof(time_t) << 3) - 1)) - 1) -#define DUAL_TIMESTAMP_NULL ((struct dual_timestamp) { 0ULL, 0ULL }) +#define DUAL_TIMESTAMP_NULL ((struct dual_timestamp) {}) +#define TRIPLE_TIMESTAMP_NULL ((struct triple_timestamp) {}) usec_t now(clockid_t clock); nsec_t now_nsec(clockid_t clock); @@ -79,11 +86,28 @@ dual_timestamp* dual_timestamp_from_realtime(dual_timestamp *ts, usec_t u); dual_timestamp* dual_timestamp_from_monotonic(dual_timestamp *ts, usec_t u); dual_timestamp* dual_timestamp_from_boottime_or_monotonic(dual_timestamp *ts, usec_t u); +triple_timestamp* triple_timestamp_get(triple_timestamp *ts); +triple_timestamp* triple_timestamp_from_realtime(triple_timestamp *ts, usec_t u); + +#define DUAL_TIMESTAMP_HAS_CLOCK(clock) \ + IN_SET(clock, CLOCK_REALTIME, CLOCK_REALTIME_ALARM, CLOCK_MONOTONIC) + +#define TRIPLE_TIMESTAMP_HAS_CLOCK(clock) \ + IN_SET(clock, CLOCK_REALTIME, CLOCK_REALTIME_ALARM, CLOCK_MONOTONIC, CLOCK_BOOTTIME, CLOCK_BOOTTIME_ALARM) + static inline bool dual_timestamp_is_set(dual_timestamp *ts) { return ((ts->realtime > 0 && ts->realtime != USEC_INFINITY) || (ts->monotonic > 0 && ts->monotonic != USEC_INFINITY)); } +static inline bool triple_timestamp_is_set(triple_timestamp *ts) { + return ((ts->realtime > 0 && ts->realtime != USEC_INFINITY) || + (ts->monotonic > 0 && ts->monotonic != USEC_INFINITY) || + (ts->boottime > 0 && ts->boottime != USEC_INFINITY)); +} + +usec_t triple_timestamp_by_clock(triple_timestamp *ts, clockid_t clock); + usec_t timespec_load(const struct timespec *ts) _pure_; struct timespec *timespec_store(struct timespec *ts, usec_t u); @@ -113,6 +137,7 @@ int get_timezones(char ***l); bool timezone_is_valid(const char *name); bool clock_boottime_supported(void); +bool clock_supported(clockid_t clock); clockid_t clock_boottime_or_monotonic(void); #define xstrftime(buf, fmt, tm) \ -- cgit v1.2.3-54-g00ecf