+++ /dev/null
-/*
-
- silctask.c
-
- Author: Pekka Riikonen <priikone@poseidon.pspt.fi>
-
- Copyright (C) 1998 - 2000 Pekka Riikonen
-
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
- (at your option) any later version.
-
- This program 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 General Public License for more details.
-
-*/
-/*
- * $Id$
- * $Log$
- * Revision 1.2 2000/07/05 06:06:35 priikone
- * Global cosmetic change.
- *
- * Revision 1.1.1.1 2000/06/27 11:36:55 priikone
- * Imported from internal CVS/Added Log headers.
- *
- *
- */
-
-#include "silcincludes.h"
-
-/* Allocates a new task queue into the Silc. If 'valid' is TRUE the
- queue becomes valid task queue. If it is FALSE scheduler will skip
- the queue. */
-
-void silc_task_queue_alloc(SilcTaskQueue *new, int valid)
-{
-
- SILC_LOG_DEBUG(("Allocating new task queue"));
-
- *new = silc_calloc(1, sizeof(**new));
-
- /* Set the pointers */
- (*new)->valid = valid;
- (*new)->task = NULL;
- (*new)->register_task = silc_task_register;
- (*new)->unregister_task = silc_task_unregister;
- (*new)->set_iotype = silc_task_set_iotype;
- (*new)->reset_iotype = silc_task_reset_iotype;
-}
-
-/* Free's a task queue. */
-
-void silc_task_queue_free(SilcTaskQueue old)
-{
- if (old)
- silc_free(old);
-}
-
-/* Adds a non-timeout task into the task queue. This function is used
- by silc_task_register function. Returns a pointer to the registered
- task. */
-
-SilcTask silc_task_add(SilcTaskQueue queue, SilcTask new,
- SilcTaskPriority priority)
-{
- SilcTask task, next, prev;
-
- /* Take the first task in the queue */
- task = queue->task;
-
- switch(priority) {
- case SILC_TASK_PRI_LOW:
- /* Lowest priority. The task is added at the end of the list. */
- prev = task->prev;
- new->prev = prev;
- new->next = task;
- prev->next = new;
- task->prev = new;
- break;
- case SILC_TASK_PRI_NORMAL:
- /* Normal priority. The task is added before lower priority tasks
- but after tasks with higher priority. */
- prev = task->prev;
- while(prev != task) {
- if (prev->priority > SILC_TASK_PRI_LOW &&
- prev->priority <= SILC_TASK_PRI_REALTIME)
- break;
- prev = prev->prev;
- }
- if (prev == task) {
- /* There are only lower priorities in the list, we will
- sit before them and become the first task in the queue. */
- prev = task->prev;
- new->prev = prev;
- new->next = task;
- task->prev = new;
- prev->next = new;
-
- /* We are now the first task in queue */
- queue->task = new;
- } else {
- /* Found a spot from the list, add the task to the list. */
- next = prev->next;
- new->prev = prev;
- new->next = next;
- prev->next = new;
- next->prev = new;
- }
- break;
- case SILC_TASK_PRI_HIGH:
- /* High priority. The task is added before lower priority tasks
- but after tasks with higher priority. */
- prev = task->prev;
- while(prev != task) {
- if (prev->priority > SILC_TASK_PRI_NORMAL &&
- prev->priority <= SILC_TASK_PRI_REALTIME)
- break;
- prev = prev->prev;
- }
- if (prev == task) {
- /* There are only lower priorities in the list, we will
- sit before them and become the first task in the queue. */
- prev = task->prev;
- new->prev = prev;
- new->next = task;
- task->prev = new;
- prev->next = new;
-
- /* We are now the first task in queue */
- queue->task = new;
- } else {
- /* Found a spot from the list, add the task to the list. */
- next = prev->next;
- new->prev = prev;
- new->next = next;
- prev->next = new;
- next->prev = new;
- }
- break;
- case SILC_TASK_PRI_REALTIME:
- /* Highest priority. The task is added at the head of the list.
- The last registered task is added to the very head of the list
- thus we get the LIFO (Last-In-First-Out) order. */
- prev = task->prev;
- new->prev = prev;
- new->next = task;
- prev->next = new;
- task->prev = new;
-
- /* We are the first task in the queue */
- queue->task = new;
- break;
- default:
- silc_free(new);
- return NULL;
- }
-
- return new;
-}
-
-/* Adds a timeout task into the task queue. This function is used by
- silc_task_register function. Returns a pointer to the registered
- task. Timeout tasks are sorted by their timeout value in ascending
- order. The priority matters if there are more than one task with
- same timeout. */
-
-SilcTask silc_task_add_timeout(SilcTaskQueue queue, SilcTask new,
- SilcTaskPriority priority)
-{
- SilcTask task, prev, next;
-
- /* Take the first task in the queue */
- task = queue->task;
-
- /* Take last task from the list */
- prev = task->prev;
-
- switch(priority) {
- case SILC_TASK_PRI_LOW:
- /* Lowest priority. The task is added at the end of the list. */
- while(prev != task) {
-
- /* If we have longer timeout than with the task head of us
- we have found our spot. */
- if (silc_task_timeout_compare(&prev->timeout, &new->timeout))
- break;
-
- /* If we are equal size of timeout we will be after it. */
- if (!silc_task_timeout_compare(&new->timeout, &prev->timeout))
- break;
-
- /* We have shorter timeout, compare to next one. */
- prev = prev->prev;
- }
- /* Found a spot from the list, add the task to the list. */
- next = prev->next;
- new->prev = prev;
- new->next = next;
- prev->next = new;
- next->prev = new;
-
- if (prev == task) {
- /* Check if we are going to be the first task in the queue */
- if (silc_task_timeout_compare(&prev->timeout, &new->timeout))
- break;
- if (!silc_task_timeout_compare(&new->timeout, &prev->timeout))
- break;
-
- /* We are now the first task in queue */
- queue->task = new;
- }
- break;
- case SILC_TASK_PRI_NORMAL:
- /* Normal priority. The task is added before lower priority tasks
- but after tasks with higher priority. */
- while(prev != task) {
-
- /* If we have longer timeout than with the task head of us
- we have found our spot. */
- if (silc_task_timeout_compare(&prev->timeout, &new->timeout))
- break;
-
- /* If we are equal size of timeout, priority kicks in place. */
- if (!silc_task_timeout_compare(&new->timeout, &prev->timeout))
- if (prev->priority >= SILC_TASK_PRI_NORMAL)
- break;
-
- /* We have shorter timeout or higher priority, compare to next one. */
- prev = prev->prev;
- }
- /* Found a spot from the list, add the task to the list. */
- next = prev->next;
- new->prev = prev;
- new->next = next;
- prev->next = new;
- next->prev = new;
-
- if (prev == task) {
- /* Check if we are going to be the first task in the queue */
- if (silc_task_timeout_compare(&prev->timeout, &new->timeout))
- break;
- if (!silc_task_timeout_compare(&new->timeout, &prev->timeout))
- if (prev->priority >= SILC_TASK_PRI_NORMAL)
- break;
-
- /* We are now the first task in queue */
- queue->task = new;
- }
- break;
- case SILC_TASK_PRI_HIGH:
- /* High priority. The task is added before lower priority tasks
- but after tasks with higher priority. */
- while(prev != task) {
-
- /* If we have longer timeout than with the task head of us
- we have found our spot. */
- if (silc_task_timeout_compare(&prev->timeout, &new->timeout))
- break;
-
- /* If we are equal size of timeout, priority kicks in place. */
- if (!silc_task_timeout_compare(&new->timeout, &prev->timeout))
- if (prev->priority >= SILC_TASK_PRI_HIGH)
- break;
-
- /* We have shorter timeout or higher priority, compare to next one. */
- prev = prev->prev;
- }
- /* Found a spot from the list, add the task to the list. */
- next = prev->next;
- new->prev = prev;
- new->next = next;
- prev->next = new;
- next->prev = new;
-
- if (prev == task) {
- /* Check if we are going to be the first task in the queue */
- if (silc_task_timeout_compare(&prev->timeout, &new->timeout))
- break;
- if (!silc_task_timeout_compare(&new->timeout, &prev->timeout))
- if (prev->priority >= SILC_TASK_PRI_HIGH)
- break;
-
- /* We are now the first task in queue */
- queue->task = new;
- }
- break;
- case SILC_TASK_PRI_REALTIME:
- /* Highest priority. The task is added at the head of the list.
- The last registered task is added to the very head of the list
- thus we get the LIFO (Last-In-First-Out) order. */
- next = task->next;
- while(next != task) {
-
- /* If we have shorter timeout than the next task we've found
- our spot. */
- if (silc_task_timeout_compare(&new->timeout, &next->timeout))
- break;
-
- /* If we are equal size of timeout we will be first. */
- if (!silc_task_timeout_compare(&next->timeout, &new->timeout))
- break;
-
- /* We have longer timeout, compare to next one. */
- next = next->next;
- }
- /* Found a spot from the list, add the task to the list. */
- prev = next->prev;
- new->next = next;
- new->prev = prev;
- prev->next = new;
- next->prev = new;
-
- if (next == task) {
- /* Check if we are going to be the first task in the queue */
- if (silc_task_timeout_compare(&next->timeout, &new->timeout))
- break;
-
- /* We are now the first task in queue */
- queue->task = new;
- }
- default:
- silc_free(new);
- return NULL;
- }
-
- return new;
-}
-
-/* Registers a new task into the task queue. The task becomes valid
- automatically when it is registered. Returns a pointer to the
- registered task. */
-
-SilcTask silc_task_register(SilcTaskQueue queue, int fd,
- SilcTaskCallback cb, void *context,
- long seconds, long useconds,
- SilcTaskType type, SilcTaskPriority priority)
-{
- SilcTask new;
- int timeout = 0;
-
- SILC_LOG_DEBUG(("Registering new task, fd=%d type=%d priority=%d",
- fd, type, priority));
-
- /* If the task is generic task, we check whether this task has already
- been registered. Generic tasks are registered only once and after that
- the same task applies to all file descriptors to be registered. */
- if ((type == SILC_TASK_GENERIC) && queue->task) {
- SilcTask task;
-
- task = queue->task;
- while(1) {
- if ((task->callback == cb) && (task->context == context)) {
- SILC_LOG_DEBUG(("Found matching generic task, using the match"));
-
- /* Add the fd to be listened, the task found now applies to this
- fd as well. */
- silc_schedule_set_listen_fd(fd, (1L << SILC_TASK_READ));
- return task;
- }
-
- if (queue->task == task->next)
- break;
-
- task = task->next;
- }
- }
-
- new = silc_calloc(1, sizeof(*new));
- new->fd = fd;
- new->context = context;
- new->callback = cb;
- new->valid = TRUE;
- new->priority = priority;
- new->iomask = (1L << SILC_TASK_READ);
- new->next = new;
- new->prev = new;
-
- /* If the task is non-timeout task we have to tell the scheduler that we
- would like to have these tasks scheduled at some odd distant future. */
- if (type != SILC_TASK_TIMEOUT)
- silc_schedule_set_listen_fd(fd, (1L << SILC_TASK_READ));
-
- /* Create timeout if marked to be timeout task */
- if (((seconds + useconds) > 0) && (type == SILC_TASK_TIMEOUT)) {
- gettimeofday(&new->timeout, NULL);
- new->timeout.tv_sec += seconds + (useconds / 1000000L);
- new->timeout.tv_usec += (useconds % 1000000L);
- if (new->timeout.tv_usec > 999999L) {
- new->timeout.tv_sec += 1;
- new->timeout.tv_usec -= 1000000L;
- }
- timeout = 1;
- }
-
- /* Is this first task of the queue? */
- if (queue->task == NULL) {
- queue->task = new;
- return new;
- }
-
- if (timeout)
- return silc_task_add_timeout(queue, new, priority);
- else
- return silc_task_add(queue, new, priority);
-}
-
-/* Removes (unregisters) a task from particular task queue. This function
- is used internally by scheduler. One should not call this function
- to unregister tasks, instead silc_task_unregister_task function
- should be used. */
-
-int silc_task_remove(SilcTaskQueue queue, SilcTask task)
-{
- SilcTask first, old, next;
-
- if (!queue || !queue->task)
- return FALSE;
-
- first = queue->task;
-
- /* Unregister all tasks in queue */
- if (task == SILC_ALL_TASKS) {
- SILC_LOG_DEBUG(("Removing all tasks at once"));
- next = first;
-
- while(1) {
- next = next->next;
- silc_free(next->prev);
- if (next == first)
- break;
- }
-
- queue->task = NULL;
- return TRUE;
- }
-
- SILC_LOG_DEBUG(("Removing task"));
-
- /* Unregister the task */
- old = first;
- while(1) {
- if (old == task) {
- SilcTask prev, next;
-
- prev = old->prev;
- next = old->next;
- prev->next = next;
- next->prev = prev;
-
- if (prev == old && next == old)
- queue->task = NULL;
- if (queue->task == old)
- queue->task = next;
-
- silc_free(old);
- return TRUE;
- }
- old = old->next;
-
- if (old == first)
- return FALSE;
- }
-}
-
-/* Unregisters a task from the task queue. This is the unregister_task
- function pointer in task queue object. One should use this function
- to unregister tasks. This function invalidates the task. */
-
-void silc_task_unregister(SilcTaskQueue queue, SilcTask task)
-{
-
- /* Unregister all tasks */
- if (task == SILC_ALL_TASKS) {
- SilcTask next;
- SILC_LOG_DEBUG(("Unregistering all tasks at once"));
-
- if (queue->task == NULL)
- return;
-
- next = queue->task;
-
- while(1) {
- if (next->valid)
- next->valid = FALSE;
- if (queue->task == next->next)
- break;
- next = next->next;
- }
- return;
- }
-
- SILC_LOG_DEBUG(("Unregistering task"));
-
- /* Unregister the specific task */
- if (task->valid)
- task->valid = FALSE;
-}
-
-/* Unregister a task by file descriptor. This invalidates the task. */
-
-void silc_task_unregister_by_fd(SilcTaskQueue queue, int fd)
-{
- SilcTask next;
-
- SILC_LOG_DEBUG(("Unregister task by fd"));
-
- if (queue->task == NULL)
- return;
-
- next = queue->task;
-
- while(1) {
- if (next->fd == fd)
- next->valid = FALSE;
- if (queue->task == next->next)
- break;
- next = next->next;
- }
-}
-
-/* Sets the I/O mask for the task. Only one I/O type can be set at a
- time. */
-
-void silc_task_set_iotype(SilcTask task, int type)
-{
- task->iomask |= (1L << type);
-}
-
-/* Resets the I/O mask to the type sent as argument. */
-
-void silc_task_reset_iotype(SilcTask task, int type)
-{
- task->iomask = (1L << type);
-}
-
-/* Compare two time values. If the first argument is smaller than the
- second this function returns TRUE. */
-
-int silc_task_timeout_compare(struct timeval *smaller,
- struct timeval *bigger)
-{
- if ((smaller->tv_sec < bigger->tv_sec) ||
- ((smaller->tv_sec == bigger->tv_sec) &&
- (smaller->tv_usec < bigger->tv_usec)))
- return TRUE;
-
- return FALSE;
-}
projects / silc.git / blobdiff