haiku/headers/private/kernel/timer.h
lillo 65918f386e forgot a little thing
git-svn-id: file:///srv/svn/repos/haiku/trunk/current@355 a95241bf-73f2-0310-859d-f6bbb57e9c96
2002-07-20 23:06:32 +00:00

97 lines
2.5 KiB
C
Executable File

#ifndef _KERNEL_TIMER_H
#define _KERNEL_TIMER_H
/**
* @file kernel/timer.h
* @brief Timer structures and definitions
*/
#include <stage2.h>
/**
* @defgroup Timer Timer structures (not architecture specific)
* @ingroup OpenBeOS_Kernel
* @{
*/
#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */
typedef struct timer timer;
typedef struct qent qent;
typedef int32 (*timer_hook)(timer *);
/**
* qent structure
*/
/**
* The BeOS qent structure is probably part of a general double linked list
* interface used all over the kernel; a struct is required to have a qent
* entry struct as first element, so it can be linked to other elements
* easily. The key field is probably just an id, eventually used to order
* the list.
* Since we don't use this kind of interface, but we have to provide it
* to keep compatibility, we can use the qent struct for other purposes...
*/
struct qent {
int64 key; /* We use this as the sched time */
qent *next; /* This is used as a pointer to next timer */
qent *prev; /* This can be used for callback args */
};
/**
* Timer event data structure
*/
struct timer {
/** qent entry for this timer event */
qent entry;
/** This just holds the timer operating mode (relative/absolute/periodic) */
uint16 flags;
/** Number of the CPU associated to this timer event */
uint16 cpu;
/** Hook function to be called on timer expiration */
timer_hook hook;
/** Expiration time in microseconds */
bigtime_t period;
};
/** @defgroup timermodes Timer operating modes
* @ingroup Timer
* @{
*/
/** @def B_ONE_SHOT_ABSOLUTE_TIMER the timer will fire once at the system
* time specified by period
*/
/** @def B_ONE_SHOT_RELATIVE_TIMER the timer will fire once in approximately
* period microseconds
*/
/** @def B_PERIODIC_TIMER the timer will fire every period microseconds,
* starting in period microseconds
*/
#define B_ONE_SHOT_ABSOLUTE_TIMER 1
#define B_ONE_SHOT_RELATIVE_TIMER 2
#define B_PERIODIC_TIMER 3
/** @} */
status_t add_timer(timer *event, timer_hook hook, bigtime_t period, int32 flags);
bool cancel_timer(timer *event);
void spin(bigtime_t microseconds);
/** kernel functions */
int timer_init(kernel_args *);
int timer_interrupt(void);
/** these two are only to be used by the scheduler */
int local_timer_cancel_event(timer *event);
int _local_timer_cancel_event(int curr_cpu, timer *event);
#ifdef __cplusplus
}
#endif /* __cplusplus */
/** @} */
#endif /* _KERNEL_TIMER_H */