Move to kernel style SPDX license identifiers

[babeltrace.git] / include / babeltrace2-ctf-writer / clock.h

/*
 * SPDX-License-Identifier: MIT
 *
 * Copyright (C) 2010-2019 EfficiOS Inc. and Linux Foundation
 */

#ifndef BABELTRACE2_CTF_WRITER_CLOCK_H
#define BABELTRACE2_CTF_WRITER_CLOCK_H

#include <stdint.h>
#include <babeltrace2-ctf-writer/object.h>
#include <babeltrace2-ctf-writer/types.h>

#ifdef __cplusplus
extern "C" {
#endif

struct bt_ctf_clock;
struct bt_ctf_clock_class;

/*
 * bt_ctf_clock_create: create a clock.
 *
 * Allocate a new clock setting its reference count to 1.
 *
 * @param name Name of the clock (will be copied); can be set to NULL
 *             for nameless clocks.
 *
 * Returns an allocated clock on success, NULL on error.
 */
extern struct bt_ctf_clock *bt_ctf_clock_create(const char *name);

/*
 * bt_ctf_clock_get_name: get a clock's name.
 *
 * Get the clock's name.
 *
 * @param clock Clock instance.
 *
 * Returns the clock's name, NULL on error.
 */
extern const char *bt_ctf_clock_get_name(struct bt_ctf_clock *clock);

/*
 * bt_ctf_clock_get_description: get a clock's description.
 *
 * Get the clock's description.
 *
 * @param clock Clock instance.
 *
 * Returns the clock's description, NULL if unset.
 */
extern const char *bt_ctf_clock_get_description(struct bt_ctf_clock *clock);

/*
 * bt_ctf_clock_set_description: set a clock's description.
 *
 * Set the clock's description. The description appears in the clock's TSDL
 * meta-data.
 *
 * @param clock Clock instance.
 * @param desc Description of the clock.
 *
 * Returns 0 on success, a negative value on error.
 */
extern int bt_ctf_clock_set_description(struct bt_ctf_clock *clock,
        const char *desc);

/*
 * bt_ctf_clock_get_frequency: get a clock's frequency.
 *
 * Get the clock's frequency (Hz).
 *
 * @param clock Clock instance.
 *
 * Returns the clock's frequency, -1ULL on error.
 */
extern uint64_t bt_ctf_clock_get_frequency(struct bt_ctf_clock *clock);

/*
 * bt_ctf_clock_set_frequency: set a clock's frequency.
 *
 * Set the clock's frequency (Hz).
 *
 * @param clock Clock instance.
 * @param freq Clock's frequency in Hz, defaults to 1 000 000 000 Hz (1ns).
 *
 * Returns 0 on success, a negative value on error.
 */
extern int bt_ctf_clock_set_frequency(struct bt_ctf_clock *clock,
        uint64_t freq);

/*
 * bt_ctf_clock_get_precision: get a clock's precision.
 *
 * Get the clock's precision (in clock ticks).
 *
 * @param clock Clock instance.
 *
 * Returns the clock's precision, -1ULL on error.
 */
extern uint64_t bt_ctf_clock_get_precision(struct bt_ctf_clock *clock);

/*
 * bt_ctf_clock_set_precision: set a clock's precision.
 *
 * Set the clock's precision.
 *
 * @param clock Clock instance.
 * @param precision Clock's precision in clock ticks, defaults to 1.
 *
 * Returns 0 on success, a negative value on error.
 */
extern int bt_ctf_clock_set_precision(struct bt_ctf_clock *clock,
        uint64_t precision);

/*
 * bt_ctf_clock_get_offset_s: get a clock's offset in seconds.
 *
 * Get the clock's offset in seconds from POSIX.1 Epoch, 1970-01-01.
 *
 * @param clock Clock instance.
 * @param offset_s Pointer to clock offset in seconds (output).
 *
 * Returns 0 on success, a negative value on error.
 */
extern int bt_ctf_clock_get_offset_s(struct bt_ctf_clock *clock,
        int64_t *offset_s);

/*
 * bt_ctf_clock_set_offset_s: set a clock's offset in seconds.
 *
 * Set the clock's offset in seconds from POSIX.1 Epoch, 1970-01-01,
 * defaults to 0.
 *
 * @param clock Clock instance.
 * @param offset_s Clock's offset in seconds, defaults to 0.
 *
 * Returns 0 on success, a negative value on error.
 */
extern int bt_ctf_clock_set_offset_s(struct bt_ctf_clock *clock,
        int64_t offset_s);

/*
 * bt_ctf_clock_get_offset: get a clock's offset in ticks.
 *
 * Get the clock's offset in ticks from Epoch + offset_t.
 *
 * @param clock Clock instance.
 * @param offset Clock offset in ticks from Epoch + offset_s (output).
 *
 * Returns 0 on success, a negative value on error.
 */
extern int bt_ctf_clock_get_offset(struct bt_ctf_clock *clock,
        int64_t *offset);

/*
 * bt_ctf_clock_set_offset: set a clock's offset in ticks.
 *
 * Set the clock's offset in ticks from Epoch + offset_s.
 *
 * @param clock Clock instance.
 * @param offset Clock's offset in ticks from Epoch + offset_s, defaults to 0.
 *
 * Returns 0 on success, a negative value on error.
 */
extern int bt_ctf_clock_set_offset(struct bt_ctf_clock *clock,
        int64_t offset);

/*
 * bt_ctf_clock_get_is_absolute: get a clock's absolute attribute.
 *
 * Get the clock's absolute attribute. A clock is absolute if the clock is a
 * global reference across the trace's other clocks.
 *
 * @param clock Clock instance.
 *
 * Returns the clock's absolute attribute, a negative value on error.
 */
extern int bt_ctf_clock_get_is_absolute(struct bt_ctf_clock *clock);

/*
 * bt_ctf_clock_set_is_absolute: set a clock's absolute attribute.
 *
 * Set the clock's absolute attribute. A clock is absolute if the clock is a
 * global reference across the trace's other clocks.
 *
 * @param clock Clock instance.
 * @param is_absolute Clock's absolute attribute, defaults to FALSE.
 *
 * Returns 0 on success, a negative value on error.
 */
extern int bt_ctf_clock_set_is_absolute(struct bt_ctf_clock *clock,
        int is_absolute);

/*
 * bt_ctf_clock_get_uuid: get a clock's UUID.
 *
 * Get the clock's UUID.
 *
 * @param clock Clock instance.
 *
 * Returns a pointer to the clock's UUID (16 byte array) on success,
 * NULL on error.
 */
extern const uint8_t *bt_ctf_clock_get_uuid(struct bt_ctf_clock *clock);

/*
 * bt_ctf_clock_set_uuid: set a clock's UUID.
 *
 * Set a clock's UUID.
 *
 * @param clock Clock instance.
 * @param uuid A 16-byte array containing a UUID.
 *
 * Returns 0 on success, a negative value on error.
 */
extern int bt_ctf_clock_set_uuid(struct bt_ctf_clock *clock,
        const uint8_t *uuid);

/*
 * bt_ctf_clock_set_time: set a clock's current time value.
 *
 * Set the current time in nanoseconds since the clock's origin (offset and
 * offset_s attributes). Defaults to 0.
 *
 * Returns 0 on success, a negative value on error.
 */
extern int bt_ctf_clock_set_time(struct bt_ctf_clock *clock,
		int64_t time);

/*
 * bt_ctf_clock_get and bt_ctf_clock_put: increment and decrement the
 * refcount of the clock
 *
 * You may also use bt_ctf_get() and bt_ctf_put() with clock objects.
 *
 * These functions ensure that the clock won't be destroyed when it
 * is in use. The same number of get and put (plus one extra put to
 * release the initial reference done at creation) has to be done to
 * destroy a clock.
 *
 * When the clock refcount is decremented to 0 by a bt_ctf_clock_put,
 * the clock is freed.
 *
 * @param clock Clock instance.
 */

/* Pre-2.0 CTF writer compatibility */
static inline
void bt_ctf_clock_get(struct bt_ctf_clock *clock)
{
        bt_ctf_object_get_ref(clock);
}

/* Pre-2.0 CTF writer compatibility */
static inline
void bt_ctf_clock_put(struct bt_ctf_clock *clock)
{
        bt_ctf_object_put_ref(clock);
}
#ifdef __cplusplus
}
#endif

#endif /* BABELTRACE2_CTF_WRITER_CLOCK_H */