include/linux/time.h

Source file repositories/reference/linux-study-clean/include/linux/time.h

File Facts

System
Linux kernel
Corpus path
include/linux/time.h
Extension
.h
Size
3216 bytes
Lines
103
Domain
Core OS
Bucket
Core Kernel Interface
Inferred role
Core OS: implementation source
Status
source implementation candidate

Why This File Exists

Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.

Dependency Surface

Detected Declarations

Annotated Snippet

struct tm {
	/*
	 * the number of seconds after the minute, normally in the range
	 * 0 to 59, but can be up to 60 to allow for leap seconds
	 */
	int tm_sec;
	/* the number of minutes after the hour, in the range 0 to 59*/
	int tm_min;
	/* the number of hours past midnight, in the range 0 to 23 */
	int tm_hour;
	/* the day of the month, in the range 1 to 31 */
	int tm_mday;
	/* the number of months since January, in the range 0 to 11 */
	int tm_mon;
	/* the number of years since 1900 */
	long tm_year;
	/* the number of days since Sunday, in the range 0 to 6 */
	int tm_wday;
	/* the number of days since January 1, in the range 0 to 365 */
	int tm_yday;
};

void time64_to_tm(time64_t totalsecs, int offset, struct tm *result);

# include <linux/time32.h>

static inline bool itimerspec64_valid(const struct itimerspec64 *its)
{
	if (!timespec64_valid(&(its->it_interval)) ||
		!timespec64_valid(&(its->it_value)))
		return false;

	return true;
}

/**
 * time_after32 - compare two 32-bit relative times
 * @a:	the time which may be after @b
 * @b:	the time which may be before @a
 *
 * time_after32(a, b) returns true if the time @a is after time @b.
 * time_before32(b, a) returns true if the time @b is before time @a.
 *
 * Similar to time_after(), compare two 32-bit timestamps for relative
 * times.  This is useful for comparing 32-bit seconds values that can't
 * be converted to 64-bit values (e.g. due to disk format or wire protocol
 * issues) when it is known that the times are less than 68 years apart.
 */
#define time_after32(a, b)	((s32)((u32)(b) - (u32)(a)) < 0)
#define time_before32(b, a)	time_after32(a, b)

/**
 * time_between32 - check if a 32-bit timestamp is within a given time range
 * @t:	the time which may be within [l,h]
 * @l:	the lower bound of the range
 * @h:	the higher bound of the range
 *
 * time_before32(t, l, h) returns true if @l <= @t <= @h. All operands are
 * treated as 32-bit integers.
 *
 * Equivalent to !(time_before32(@t, @l) || time_after32(@t, @h)).
 */
#define time_between32(t, l, h) ((u32)(h) - (u32)(l) >= (u32)(t) - (u32)(l))

# include <vdso/time.h>

#endif

Annotation

Implementation Notes