/*
This file is part of GNUnet
Copyright (C) 2009-2016 GNUnet e.V.
GNUnet is free software: you can redistribute it and/or modify it
under the terms of the GNU Affero General Public License as published
by the Free Software Foundation, either version 3 of the License,
or (at your option) any later version.
GNUnet is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Affero General Public License for more details.
You should have received a copy of the GNU Affero General Public License
along with this program. If not, see .
SPDX-License-Identifier: AGPL3.0-or-later
*/
/**
* @author Christian Grothoff
*
* @file
* API to schedule computations using continuation passing style
*
* @defgroup scheduler Scheduler library
* Event loop (scheduler)
*
* Schedule computations using continuation passing style.
*
* @{
*/
#ifndef GNUNET_SCHEDULER_LIB_H
#define GNUNET_SCHEDULER_LIB_H
#ifdef __cplusplus
extern "C"
{
#if 0 /* keep Emacsens' auto-indent happy */
}
#endif
#endif
/**
* Opaque reference to a task.
*/
struct GNUNET_SCHEDULER_Task;
/**
* Reasons why the schedule may have triggered
* the task now.
*/
enum GNUNET_SCHEDULER_Reason
{
/**
* This task is not ready.
*/
GNUNET_SCHEDULER_REASON_NONE = 0,
/**
* This is the very first task run during startup.
*/
GNUNET_SCHEDULER_REASON_STARTUP = 1,
/**
* We are shutting down and are running all shutdown-related tasks.
*/
GNUNET_SCHEDULER_REASON_SHUTDOWN = 2,
/**
* The specified timeout has expired.
* (also set if the delay given was 0).
*/
GNUNET_SCHEDULER_REASON_TIMEOUT = 4,
/**
* The reading socket is ready.
*/
GNUNET_SCHEDULER_REASON_READ_READY = 8,
/**
* The writing socket is ready.
*/
GNUNET_SCHEDULER_REASON_WRITE_READY = 16,
/**
* The prerequisite task is done.
*/
GNUNET_SCHEDULER_REASON_PREREQ_DONE = 32
};
#include "gnunet_time_lib.h"
#include "gnunet_network_lib.h"
/**
* Possible events on FDs, used as a bitmask.
* Modelled after GPollFD.
*/
enum GNUNET_SCHEDULER_EventType
{
/**
* No event (useful for timeout).
*/
GNUNET_SCHEDULER_ET_NONE = 0,
/**
* Data available for reading.
*/
GNUNET_SCHEDULER_ET_IN = 1,
/**
* Buffer available for writing.
*/
GNUNET_SCHEDULER_ET_OUT = 2,
/**
*
*/
GNUNET_SCHEDULER_ET_HUP = 4,
/**
*
*/
GNUNET_SCHEDULER_ET_ERR = 8,
/**
*
*/
GNUNET_SCHEDULER_ET_PRI = 16,
/**
*
*/
GNUNET_SCHEDULER_ET_NVAL = 32
};
/**
* Information about an event relating to a file descriptor/socket.
*/
struct GNUNET_SCHEDULER_FdInfo
{
/**
* GNUnet network socket the event is about, matches @a sock,
* NULL if this is about a file handle or if no network
* handle was given to the scheduler originally.
*/
const struct GNUNET_NETWORK_Handle *fd;
/**
* GNUnet file handle the event is about, matches @a sock,
* NULL if this is about a network socket or if no network
* handle was given to the scheduler originally.
*/
const struct GNUNET_DISK_FileHandle *fh;
/**
* Type of the event that was generated related to @e sock.
*/
enum GNUNET_SCHEDULER_EventType et;
/**
* Underlying OS handle the event was about.
*/
int sock;
};
/**
* Context information passed to each scheduler task.
*/
struct GNUNET_SCHEDULER_TaskContext
{
/**
* Reason why the task is run now
*/
enum GNUNET_SCHEDULER_Reason reason;
/**
* Length of the following array.
*/
unsigned int fds_len;
/**
* Array of length @e fds_len with information about ready FDs.
* Note that we use the same format regardless of the internal
* event loop that was used. The given array should only contain
* information about file descriptors relevant to the current task.
*/
const struct GNUNET_SCHEDULER_FdInfo *fds;
/**
* Set of file descriptors ready for reading; note that additional
* bits may be set that were not in the original request.
* @deprecated
*/
const struct GNUNET_NETWORK_FDSet *read_ready;
/**
* Set of file descriptors ready for writing; note that additional
* bits may be set that were not in the original request.
* @deprecated
*/
const struct GNUNET_NETWORK_FDSet *write_ready;
};
/**
* Function used by event-loop implementations to signal the scheduler
* that a particular @a task is ready due to an event specified in the
* et field of @a fdi.
*
* This function will then queue the task to notify the application
* that the task is ready (with the respective priority).
*
* @param task the task that is ready
* @param fdi information about the related FD
*/
void
GNUNET_SCHEDULER_task_ready (struct GNUNET_SCHEDULER_Task *task,
struct GNUNET_SCHEDULER_FdInfo *fdi);
/**
* Handle to the scheduler's state to be used by the driver.
*/
struct GNUNET_SCHEDULER_Handle;
/**
* Function called by external event loop implementations to tell the
* scheduler to run some of the tasks that are ready. Must be called
* only after #GNUNET_SCHEDULER_driver_init has been called and before
* #GNUNET_SCHEDULER_driver_done is called.
* This function may return even though there are tasks left to run
* just to give other tasks a chance as well. If we return #GNUNET_YES,
* the event loop implementation should call this function again as
* soon as possible, while if we return #GNUNET_NO it must block until
* either the operating system has more work (the scheduler has no more
* work to do right now) or the timeout set by the scheduler (using the
* set_wakeup callback) is reached.
*
* @param sh scheduler handle that was returned by
* #GNUNET_SCHEDULER_driver_init
* @return #GNUNET_YES if there are more tasks that are ready,
* and thus we would like to run more (yield to avoid
* blocking other activities for too long) #GNUNET_NO
* if we are done running tasks (yield to block)
*/
int
GNUNET_SCHEDULER_do_work (struct GNUNET_SCHEDULER_Handle *sh);
/**
* API an external event loop has to implement for
* #GNUNET_SCHEDULER_driver_init.
*/
struct GNUNET_SCHEDULER_Driver
{
/**
* Closure to pass to the functions in this struct.
*/
void *cls;
/**
* Add a @a task to be run if the conditions specified in the
* et field of the given @a fdi are satisfied. The et field will
* be cleared after this call and the driver is expected to set
* the type of the actual event before passing @a fdi to
* #GNUNET_SCHEDULER_task_ready.
*
* @param cls closure
* @param task task to add
* @param fdi conditions to watch for
* @return #GNUNET_OK on success, #GNUNET_SYSERR on failure
* (i.e. @a fdi too high or invalid)
*/
int
(*add)(void *cls,
struct GNUNET_SCHEDULER_Task *task,
struct GNUNET_SCHEDULER_FdInfo *fdi);
/**
* Delete a @a task from the set of tasks to be run. A task may
* comprise multiple FdInfo entries previously added with the add
* function. The driver is expected to delete them all.
*
* @param cls closure
* @param task task to delete
* @return #GNUNET_OK on success, #GNUNET_SYSERR on failure
* (i.e. @a task does not match prior @e add call)
*/
int
(*del)(void *cls,
struct GNUNET_SCHEDULER_Task *task);
/**
* Set time at which we definitively want to get a wakeup call.
*
* @param cls closure
* @param dt time when we want to wake up next
*/
void
(*set_wakeup)(void *cls,
struct GNUNET_TIME_Absolute dt);
};
/**
* Signature of the main function of a task.
*
* @param cls closure
*/
typedef void
(*GNUNET_SCHEDULER_TaskCallback) (void *cls);
/**
* Function called by external event loop implementations to initialize
* the scheduler. An external implementation has to provide @a driver
* which contains callbacks for the scheduler (see definition of struct
* #GNUNET_SCHEDULER_Driver). The callbacks are used to instruct the
* external implementation to watch for events. If it detects any of
* those events it is expected to call #GNUNET_SCHEDULER_do_work to let
* the scheduler handle it. If an event is related to a specific task
* (e.g. the scheduler gave instructions to watch a file descriptor),
* the external implementation is expected to mark that task ready
* before by calling #GNUNET_SCHEDULER_task_ready.
*
* This function has to be called before any tasks are scheduled and
* before GNUNET_SCHEDULER_do_work is called for the first time. It
* allocates resources that have to be freed again by calling
* #GNUNET_SCHEDULER_driver_done.
*
* This function installs the same signal handlers as
* #GNUNET_SCHEDULER_run. This means SIGTERM (and other similar signals)
* will induce a call to #GNUNET_SCHEDULER_shutdown during the next
* call to #GNUNET_SCHEDULER_do_work. As a result, SIGTERM causes all
* active tasks to be scheduled with reason
* #GNUNET_SCHEDULER_REASON_SHUTDOWN. (However, tasks added afterwards
* will execute normally!). Note that any particular signal will only
* shut down one scheduler; applications should always only create a
* single scheduler.
*
* @param driver to use for the event loop
* @return handle to be passed to #GNUNET_SCHEDULER_do_work and
* #GNUNET_SCHEDULER_driver_done
*/
struct GNUNET_SCHEDULER_Handle *
GNUNET_SCHEDULER_driver_init (const struct GNUNET_SCHEDULER_Driver *driver);
/**
* Counter-part of #GNUNET_SCHEDULER_driver_init. Has to be called
* by external event loop implementations after the scheduler has
* shut down. This is the case if both of the following conditions
* are met:
*
* - all tasks the scheduler has added through the driver's add
* callback have been removed again through the driver's del
* callback
* - the timeout the scheduler has set through the driver's
* add_wakeup callback is FOREVER
*
* @param sh the handle returned by #GNUNET_SCHEDULER_driver_init
*/
void
GNUNET_SCHEDULER_driver_done (struct GNUNET_SCHEDULER_Handle *sh);
/**
* Obtain the driver for using select() as the event loop.
*
* @return NULL on error
*/
struct GNUNET_SCHEDULER_Driver *
GNUNET_SCHEDULER_driver_select (void);
/**
* Signature of the select function used by the scheduler.
* #GNUNET_NETWORK_socket_select matches it.
*
* @param cls closure
* @param rfds set of sockets to be checked for readability
* @param wfds set of sockets to be checked for writability
* @param efds set of sockets to be checked for exceptions
* @param timeout relative value when to return
* @return number of selected sockets, #GNUNET_SYSERR on error
*/
typedef int
(*GNUNET_SCHEDULER_select) (void *cls,
struct GNUNET_NETWORK_FDSet *rfds,
struct GNUNET_NETWORK_FDSet *wfds,
struct GNUNET_NETWORK_FDSet *efds,
struct GNUNET_TIME_Relative timeout);
/**
* Initialize and run scheduler. This function will return when all
* tasks have completed. On systems with signals, receiving a SIGTERM
* (and other similar signals) will cause #GNUNET_SCHEDULER_shutdown
* to be run after the active task is complete. As a result, SIGTERM
* causes all shutdown tasks to be scheduled with reason
* #GNUNET_SCHEDULER_REASON_SHUTDOWN. (However, tasks added
* afterwards will execute normally!). Note that any particular
* signal will only shut down one scheduler; applications should
* always only create a single scheduler.
*
* @param task task to run first (and immediately)
* @param task_cls closure of @a task
*/
void
GNUNET_SCHEDULER_run (GNUNET_SCHEDULER_TaskCallback task,
void *task_cls);
/**
* Initialize and run scheduler. This function will return when all
* tasks have completed. When @ install_signals is GNUNET_YES, then
* this function behaves in the same was as GNUNET_SCHEDULER_run does.
* If @ install_signals is GNUNET_NO then no signal handlers are
* installed.
*
* @param install_signals whether to install signals (GNUNET_YES/NO)
* @param task task to run first (and immediately)
* @param task_cls closure of @a task
*/
void
GNUNET_SCHEDULER_run_with_optional_signals (int install_signals,
GNUNET_SCHEDULER_TaskCallback task,
void *task_cls);
/**
* Request the shutdown of a scheduler. Marks all tasks
* awaiting shutdown as ready. Note that tasks
* scheduled with #GNUNET_SCHEDULER_add_shutdown() AFTER this call
* will be delayed until the next shutdown signal.
*/
void
GNUNET_SCHEDULER_shutdown (void);
/**
* Get information about the current load of this scheduler. Use this
* function to determine if an elective task should be added or simply
* dropped (if the decision should be made based on the number of
* tasks ready to run).
*
* @param p priority-level to query, use KEEP to query the level
* of the current task, use COUNT to get the sum over
* all priority levels
* @return number of tasks pending right now
*/
unsigned int
GNUNET_SCHEDULER_get_load (enum GNUNET_SCHEDULER_Priority p);
/**
* Obtain the reasoning why the current task was
* started.
*
* @return task context with information why the current task is run
*/
const struct GNUNET_SCHEDULER_TaskContext *
GNUNET_SCHEDULER_get_task_context (void);
/**
* Cancel the task with the specified identifier.
* The task must not yet have run. Only allowed to be called as long as the
* scheduler is running, that is one of the following conditions is met:
*
* - #GNUNET_SCHEDULER_run has been called and has not returned yet
* - #GNUNET_SCHEDULER_driver_init has been run and
* #GNUNET_SCHEDULER_driver_done has not been called yet
*
* @param task id of the task to cancel
* @return original closure of the task
*/
void *
GNUNET_SCHEDULER_cancel (struct GNUNET_SCHEDULER_Task *task);
/**
* Continue the current execution with the given function. This is
* similar to the other "add" functions except that there is no delay
* and the reason code can be specified.
*
* @param task main function of the task
* @param task_cls closure for @a task
* @param reason reason for task invocation
* @param priority priority to use for the task
*/
void
GNUNET_SCHEDULER_add_with_reason_and_priority (GNUNET_SCHEDULER_TaskCallback task,
void *task_cls,
enum GNUNET_SCHEDULER_Reason reason,
enum GNUNET_SCHEDULER_Priority priority);
/**
* Schedule a new task to be run with a specified priority.
*
* @param prio how important is the new task?
* @param task main function of the task
* @param task_cls closure of @a task
* @return unique task identifier for the job
* only valid until @a task is started!
*/
struct GNUNET_SCHEDULER_Task *
GNUNET_SCHEDULER_add_with_priority (enum GNUNET_SCHEDULER_Priority prio,
GNUNET_SCHEDULER_TaskCallback task,
void *task_cls);
/**
* Schedule a new task to be run as soon as possible. Note that this
* does not guarantee that this will be the next task that is being
* run, as other tasks with higher priority (or that are already ready
* to run) might get to run first. Just as with delays, clients must
* not rely on any particular order of execution between tasks
* scheduled concurrently.
*
* The task will be run with the DEFAULT priority.
*
* @param task main function of the task
* @param task_cls closure of @a task
* @return unique task identifier for the job
* only valid until @a task is started!
*/
struct GNUNET_SCHEDULER_Task *
GNUNET_SCHEDULER_add_now (GNUNET_SCHEDULER_TaskCallback task,
void *task_cls);
/**
* Schedule a new task to be run on shutdown, that is when a CTRL-C
* signal is received, or when #GNUNET_SCHEDULER_shutdown() is being
* invoked.
*
* @param task main function of the task
* @param task_cls closure of @a task
* @return unique task identifier for the job
* only valid until @a task is started!
*/
struct GNUNET_SCHEDULER_Task *
GNUNET_SCHEDULER_add_shutdown (GNUNET_SCHEDULER_TaskCallback task,
void *task_cls);
/**
* Schedule a new task to be run as soon as possible with the
* (transitive) ignore-shutdown flag either explicitly set or
* explicitly enabled. This task (and all tasks created from it,
* other than by another call to this function) will either count or
* not count for the 'lifeness' of the process. This API is only
* useful in a few special cases.
*
* @param lifeness #GNUNET_YES if the task counts for lifeness, #GNUNET_NO if not.
* @param task main function of the task
* @param task_cls closure of @a task
* @return unique task identifier for the job
* only valid until @a task is started!
*/
struct GNUNET_SCHEDULER_Task *
GNUNET_SCHEDULER_add_now_with_lifeness (int lifeness,
GNUNET_SCHEDULER_TaskCallback task,
void *task_cls);
/**
* Schedule a new task to be run with a specified delay. The task
* will be scheduled for execution once the delay has expired. It
* will be run with the DEFAULT priority.
*
* @param delay with which the operation should be run
* @param task main function of the task
* @param task_cls closure of @a task
* @return unique task identifier for the job
* only valid until @a task is started!
*/
struct GNUNET_SCHEDULER_Task *
GNUNET_SCHEDULER_add_delayed (struct GNUNET_TIME_Relative delay,
GNUNET_SCHEDULER_TaskCallback task,
void *task_cls);
/**
* Schedule a new task to be run at the specified time. The task
* will be scheduled for execution once specified time has been
* reached. It will be run with the DEFAULT priority.
*
* @param at time at which this operation should run
* @param task main function of the task
* @param task_cls closure of @a task
* @return unique task identifier for the job
* only valid until @a task is started!
*/
struct GNUNET_SCHEDULER_Task *
GNUNET_SCHEDULER_add_at (struct GNUNET_TIME_Absolute at,
GNUNET_SCHEDULER_TaskCallback task,
void *task_cls);
/**
* Schedule a new task to be run with a specified delay. The task
* will be scheduled for execution once the delay has expired.
*
* @param delay when should this operation time out?
* @param priority priority to use for the task
* @param task main function of the task
* @param task_cls closure of @a task
* @return unique task identifier for the job
* only valid until @a task is started!
*/
struct GNUNET_SCHEDULER_Task *
GNUNET_SCHEDULER_add_delayed_with_priority (struct GNUNET_TIME_Relative delay,
enum GNUNET_SCHEDULER_Priority priority,
GNUNET_SCHEDULER_TaskCallback task,
void *task_cls);
/**
* Schedule a new task to be run at the specified time. The task
* will be scheduled for execution at time @a at.
*
* @param at time when the operation should run
* @param priority priority to use for the task
* @param task main function of the task
* @param task_cls closure of @a task
* @return unique task identifier for the job
* only valid until @a task is started!
*/
struct GNUNET_SCHEDULER_Task *
GNUNET_SCHEDULER_add_at_with_priority (struct GNUNET_TIME_Absolute at,
enum GNUNET_SCHEDULER_Priority priority,
GNUNET_SCHEDULER_TaskCallback task,
void *task_cls);
/**
* Schedule a new task to be run with a specified delay or when the
* specified file descriptor is ready for reading. The delay can be
* used as a timeout on the socket being ready. The task will be
* scheduled for execution once either the delay has expired or the
* socket operation is ready. It will be run with the DEFAULT priority.
* Only allowed to be called as long as the scheduler is running, that
* is one of the following conditions is met:
*
* - #GNUNET_SCHEDULER_run has been called and has not returned yet
* - #GNUNET_SCHEDULER_driver_init has been run and
* #GNUNET_SCHEDULER_driver_done has not been called yet
*
* @param delay when should this operation time out?
* @param rfd read file-descriptor
* @param task main function of the task
* @param task_cls closure of @a task
* @return unique task identifier for the job
* only valid until @a task is started!
*/
struct GNUNET_SCHEDULER_Task *
GNUNET_SCHEDULER_add_read_net (struct GNUNET_TIME_Relative delay,
struct GNUNET_NETWORK_Handle *rfd,
GNUNET_SCHEDULER_TaskCallback task,
void *task_cls);
/**
* Schedule a new task to be run with a specified priority and to be
* run after the specified delay or when the specified file descriptor
* is ready for reading. The delay can be used as a timeout on the
* socket being ready. The task will be scheduled for execution once
* either the delay has expired or the socket operation is ready. It
* will be run with the DEFAULT priority.
* Only allowed to be called as long as the scheduler is running, that
* is one of the following conditions is met:
*
* - #GNUNET_SCHEDULER_run has been called and has not returned yet
* - #GNUNET_SCHEDULER_driver_init has been run and
* #GNUNET_SCHEDULER_driver_done has not been called yet
*
* @param delay when should this operation time out?
* @param priority priority to use for the task
* @param rfd read file-descriptor
* @param task main function of the task
* @param task_cls closure of @a task
* @return unique task identifier for the job
* only valid until @a task is started!
*/
struct GNUNET_SCHEDULER_Task *
GNUNET_SCHEDULER_add_read_net_with_priority (struct GNUNET_TIME_Relative delay,
enum GNUNET_SCHEDULER_Priority priority,
struct GNUNET_NETWORK_Handle *rfd,
GNUNET_SCHEDULER_TaskCallback task,
void *task_cls);
/**
* Schedule a new task to be run with a specified delay or when the
* specified file descriptor is ready for writing. The delay can be
* used as a timeout on the socket being ready. The task will be
* scheduled for execution once either the delay has expired or the
* socket operation is ready. It will be run with the priority of
* the calling task.
* Only allowed to be called as long as the scheduler is running, that
* is one of the following conditions is met:
*
* - #GNUNET_SCHEDULER_run has been called and has not returned yet
* - #GNUNET_SCHEDULER_driver_init has been run and
* #GNUNET_SCHEDULER_driver_done has not been called yet
*
* @param delay when should this operation time out?
* @param wfd write file-descriptor
* @param task main function of the task
* @param task_cls closure of @a task
* @return unique task identifier for the job
* only valid until @a task is started!
*/
struct GNUNET_SCHEDULER_Task *
GNUNET_SCHEDULER_add_write_net (struct GNUNET_TIME_Relative delay,
struct GNUNET_NETWORK_Handle *wfd,
GNUNET_SCHEDULER_TaskCallback task,
void *task_cls);
/**
* Schedule a new task to be run with a specified delay or when the
* specified file descriptor is ready. The delay can be
* used as a timeout on the socket being ready. The task will be
* scheduled for execution once either the delay has expired or the
* socket operation is ready.
* Only allowed to be called as long as the scheduler is running, that
* is one of the following conditions is met:
*
* - #GNUNET_SCHEDULER_run has been called and has not returned yet
* - #GNUNET_SCHEDULER_driver_init has been run and
* #GNUNET_SCHEDULER_driver_done has not been called yet
*
* @param delay when should this operation time out?
* @param priority priority of the task
* @param fd file-descriptor
* @param on_read whether to poll the file-descriptor for readability
* @param on_write whether to poll the file-descriptor for writability
* @param task main function of the task
* @param task_cls closure of task
* @return unique task identifier for the job
* only valid until "task" is started!
*/
struct GNUNET_SCHEDULER_Task *
GNUNET_SCHEDULER_add_net_with_priority (struct GNUNET_TIME_Relative delay,
enum GNUNET_SCHEDULER_Priority priority,
struct GNUNET_NETWORK_Handle *fd,
int on_read,
int on_write,
GNUNET_SCHEDULER_TaskCallback task,
void *task_cls);
/**
* Schedule a new task to be run with a specified delay or when the
* specified file descriptor is ready for reading. The delay can be
* used as a timeout on the socket being ready. The task will be
* scheduled for execution once either the delay has expired or the
* socket operation is ready. It will be run with the DEFAULT priority.
* Only allowed to be called as long as the scheduler is running, that
* is one of the following conditions is met:
*
* - #GNUNET_SCHEDULER_run has been called and has not returned yet
* - #GNUNET_SCHEDULER_driver_init has been run and
* #GNUNET_SCHEDULER_driver_done has not been called yet
*
* @param delay when should this operation time out?
* @param rfd read file-descriptor
* @param task main function of the task
* @param task_cls closure of @a task
* @return unique task identifier for the job
* only valid until @a task is started!
*/
struct GNUNET_SCHEDULER_Task *
GNUNET_SCHEDULER_add_read_file (struct GNUNET_TIME_Relative delay,
const struct GNUNET_DISK_FileHandle *rfd,
GNUNET_SCHEDULER_TaskCallback task,
void *task_cls);
/**
* Schedule a new task to be run with a specified delay or when the
* specified file descriptor is ready for writing. The delay can be
* used as a timeout on the socket being ready. The task will be
* scheduled for execution once either the delay has expired or the
* socket operation is ready. It will be run with the DEFAULT priority.
* Only allowed to be called as long as the scheduler is running, that
* is one of the following conditions is met:
*
* - #GNUNET_SCHEDULER_run has been called and has not returned yet
* - #GNUNET_SCHEDULER_driver_init has been run and
* #GNUNET_SCHEDULER_driver_done has not been called yet
*
* @param delay when should this operation time out?
* @param wfd write file-descriptor
* @param task main function of the task
* @param task_cls closure of @a task
* @return unique task identifier for the job
* only valid until @a task is started!
*/
struct GNUNET_SCHEDULER_Task *
GNUNET_SCHEDULER_add_write_file (struct GNUNET_TIME_Relative delay,
const struct GNUNET_DISK_FileHandle *wfd,
GNUNET_SCHEDULER_TaskCallback task,
void *task_cls);
/**
* Schedule a new task to be run with a specified delay or when the
* specified file descriptor is ready. The delay can be
* used as a timeout on the socket being ready. The task will be
* scheduled for execution once either the delay has expired or the
* socket operation is ready.
* Only allowed to be called as long as the scheduler is running, that
* is one of the following conditions is met:
*
* - #GNUNET_SCHEDULER_run has been called and has not returned yet
* - #GNUNET_SCHEDULER_driver_init has been run and
* #GNUNET_SCHEDULER_driver_done has not been called yet
*
* @param delay when should this operation time out?
* @param priority priority of the task
* @param fd file-descriptor
* @param on_read whether to poll the file-descriptor for readability
* @param on_write whether to poll the file-descriptor for writability
* @param task main function of the task
* @param task_cls closure of @a task
* @return unique task identifier for the job
* only valid until @a task is started!
*/
struct GNUNET_SCHEDULER_Task *
GNUNET_SCHEDULER_add_file_with_priority (struct GNUNET_TIME_Relative delay,
enum GNUNET_SCHEDULER_Priority priority,
const struct GNUNET_DISK_FileHandle *fd,
int on_read, int on_write,
GNUNET_SCHEDULER_TaskCallback task,
void *task_cls);
/**
* Schedule a new task to be run with a specified delay or when any of
* the specified file descriptor sets is ready. The delay can be used
* as a timeout on the socket(s) being ready. The task will be
* scheduled for execution once either the delay has expired or any of
* the socket operations is ready. This is the most general
* function of the "add" family. Note that the "prerequisite_task"
* must be satisfied in addition to any of the other conditions. In
* other words, the task will be started when
*
* (prerequisite-run)
* && (delay-ready
* || any-rs-ready
* || any-ws-ready) )
*
* Only allowed to be called as long as the scheduler is running, that
* is one of the following conditions is met:
*
* - #GNUNET_SCHEDULER_run has been called and has not returned yet
* - #GNUNET_SCHEDULER_driver_init has been run and
* #GNUNET_SCHEDULER_driver_done has not been called yet
*
* @param prio how important is this task?
* @param delay how long should we wait?
* @param rs set of file descriptors we want to read (can be NULL)
* @param ws set of file descriptors we want to write (can be NULL)
* @param task main function of the task
* @param task_cls closure of @a task
* @return unique task identifier for the job
* only valid until @a task is started!
*/
struct GNUNET_SCHEDULER_Task *
GNUNET_SCHEDULER_add_select (enum GNUNET_SCHEDULER_Priority prio,
struct GNUNET_TIME_Relative delay,
const struct GNUNET_NETWORK_FDSet *rs,
const struct GNUNET_NETWORK_FDSet *ws,
GNUNET_SCHEDULER_TaskCallback task,
void *task_cls);
/**
* Sets the select function to use in the scheduler (scheduler_select).
*
* @param new_select new select function to use (NULL to reset to default)
* @param new_select_cls closure for @a new_select
*/
void
GNUNET_SCHEDULER_set_select (GNUNET_SCHEDULER_select new_select,
void *new_select_cls);
#if 0 /* keep Emacsens' auto-indent happy */
{
#endif
#ifdef __cplusplus
}
#endif
#endif
/** @} */ /* end of group scheduler */