timeout.h

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/*-------------------------------------------------------------------------
 *
 * timeout.h
 *    Routines to multiplex SIGALRM interrupts for multiple timeout reasons.
 *
 *
 * Portions Copyright (c) 1996-2013, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 * src/include/utils/timeout.h
 *
 *-------------------------------------------------------------------------
 */
#ifndef TIMEOUT_H
#define TIMEOUT_H

#include "datatype/timestamp.h"

/*
 * Identifiers for timeout reasons.  Note that in case multiple timeouts
 * trigger at the same time, they are serviced in the order of this enum.
 */
typedef enum TimeoutId
{
    /* Predefined timeout reasons */
    STARTUP_PACKET_TIMEOUT,
    DEADLOCK_TIMEOUT,
    LOCK_TIMEOUT,
    STATEMENT_TIMEOUT,
    STANDBY_DEADLOCK_TIMEOUT,
    STANDBY_TIMEOUT,
    /* First user-definable timeout reason */
    USER_TIMEOUT,
    /* Maximum number of timeout reasons */
    MAX_TIMEOUTS = 16
} TimeoutId;

/* callback function signature */
typedef void (*timeout_handler_proc) (void);

/*
 * Parameter structure for setting multiple timeouts at once
 */
typedef enum TimeoutType
{
    TMPARAM_AFTER,
    TMPARAM_AT
} TimeoutType;

typedef struct
{
    TimeoutId   id;             /* timeout to set */
    TimeoutType type;           /* TMPARAM_AFTER or TMPARAM_AT */
    int         delay_ms;       /* only used for TMPARAM_AFTER */
    TimestampTz fin_time;       /* only used for TMPARAM_AT */
} EnableTimeoutParams;

/*
 * Parameter structure for clearing multiple timeouts at once
 */
typedef struct
{
    TimeoutId   id;             /* timeout to clear */
    bool        keep_indicator; /* keep the indicator flag? */
} DisableTimeoutParams;

/* timeout setup */
extern void InitializeTimeouts(void);
extern TimeoutId RegisterTimeout(TimeoutId id, timeout_handler_proc handler);

/* timeout operation */
extern void enable_timeout_after(TimeoutId id, int delay_ms);
extern void enable_timeout_at(TimeoutId id, TimestampTz fin_time);
extern void enable_timeouts(const EnableTimeoutParams *timeouts, int count);
extern void disable_timeout(TimeoutId id, bool keep_indicator);
extern void disable_timeouts(const DisableTimeoutParams *timeouts, int count);
extern void disable_all_timeouts(bool keep_indicators);

/* accessors */
extern bool get_timeout_indicator(TimeoutId id, bool reset_indicator);
extern TimestampTz get_timeout_start_time(TimeoutId id);

#endif   /* TIMEOUT_H */