-/*
- * Copyright (C) 2006-2014 Andre Noll <maan@systemlinux.org>
- *
- * Licensed under the GPL v2. For licencing details see COPYING.
- */
+/* Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
/** \file sched.h Sched and task structures and exported symbols from sched.c. */
* called after the select call.
*/
struct sched {
- /** Initial value before any pre_select call. */
- struct timeval default_timeout;
- /** The current timeout for the upcoming select call. */
- struct timeval select_timeout;
+ /** Initial value (in milliseconds) before any pre_select call. */
+ int default_timeout;
+ /** The timeout (also in milliseconds) for the next select call. */
+ int timeout;
/** fds that should be watched for readability. */
fd_set rfds;
/** fds that should be watched for writability. */
/** Highest numbered file descriptor in any of the above fd sets. */
int max_fileno;
/** If non-NULL, use this function instead of para_select. */
- int (*select_function)(int, fd_set *, fd_set *, struct timeval *);
+ int (*select_function)(int, fd_set *, fd_set *, int timeout);
/** Tasks which have been registered to the scheduler. */
struct list_head task_list;
};
-/**
- * Paraslash's task structure.
- *
- * Before registering a task to the scheduler, the task structure must be
- * filled in properly by the caller.
- *
- * \sa \ref sched.
- */
-struct task {
+struct task;
+
+/** Information that must be supplied by callers of \ref task_register(). */
+struct task_info {
+ /** Used for log messages and by \ref get_task_list(). */
+ const char *name;
/**
- * The optional pre select hook of \a t.
+ * The optional pre select method.
*
* Its purpose is to add file descriptors to the fd sets of the
* scheduler and to decrease the select timeout if necessary.
*/
- void (*pre_select)(struct sched *s, struct task *t);
+ void (*pre_select)(struct sched *s, void *context);
/**
- * The mandatory post select hook of \a t.
+ * The mandatory post select method.
*
* Its purpose is to evaluate and act upon the results of the previous
* select call. If this function returns a negative value, the
* scheduler unregisters the task.
*/
- int (*post_select)(struct sched *s, struct task *t);
- /** Whether this task is active (>=0) or in error state (<0). */
- int error;
- /** Position of the task in the task list of the scheduler. */
- struct list_head node;
- /** Descriptive text and current status of the task. */
- char status[255];
- /** If less than zero, the task was notified by another task. */
- int notification;
+ int (*post_select)(struct sched *s, void *context);
+ /**
+ * This pointer is saved when the task is registered. It is passed to
+ * ->pre_select() and ->post_select(). Usually this is a pointer to the
+ * struct owned by the caller which contains the task pointer.
+ */
+ void *context;
};
/**
* scheduler are allowed to block, this value should be accurate enough so that
* there is no need to call clock_gettime() directly.
*/
-extern struct timeval *now;
+extern const struct timeval *now;
-void register_task(struct sched *s, struct task *t);
+struct task *task_register(struct task_info *info, struct sched *s);
int schedule(struct sched *s);
+void sched_shutdown(struct sched *s);
char *get_task_list(struct sched *s);
void task_notify(struct task *t, int err);
void task_notify_all(struct sched *s, int err);
-int task_get_notification(struct task *t);
+int task_get_notification(const struct task *t);
+int task_status(const struct task *t);
+int task_reap(struct task **tptr);
void sched_min_delay(struct sched *s);
void sched_request_timeout(struct timeval *to, struct sched *s);
void sched_request_timeout_ms(long unsigned ms, struct sched *s);
int sched_request_barrier(struct timeval *barrier, struct sched *s);
int sched_request_barrier_or_min_delay(struct timeval *barrier, struct sched *s);
+
+static inline bool sched_read_ok(int fd, const struct sched *s)
+{
+ return FD_ISSET(fd, &s->rfds);
+}
+
+static inline bool sched_write_ok(int fd, const struct sched *s)
+{
+ return FD_ISSET(fd, &s->wfds);
+}