Sweden-Number/server/async.c

175 lines
5.3 KiB
C

/*
* Server-side async I/O support
*
* Copyright (C) 2007 Alexandre Julliard
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
*/
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include "ntstatus.h"
#define WIN32_NO_STATUS
#include "windef.h"
#include "winternl.h"
#include "object.h"
#include "file.h"
#include "request.h"
struct async
{
struct object obj; /* object header */
struct thread *thread; /* owning thread */
struct list queue_entry; /* entry in file descriptor queue */
struct timeout_user *timeout;
struct event *event;
async_data_t data; /* data for async I/O call */
};
static void async_dump( struct object *obj, int verbose );
static void async_destroy( struct object *obj );
static const struct object_ops async_ops =
{
sizeof(struct async), /* size */
async_dump, /* dump */
no_add_queue, /* add_queue */
NULL, /* remove_queue */
NULL, /* signaled */
NULL, /* satisfied */
no_signal, /* signal */
no_get_fd, /* get_fd */
no_map_access, /* map_access */
no_lookup_name, /* lookup_name */
no_open_file, /* open_file */
no_close_handle, /* close_handle */
async_destroy /* destroy */
};
static void async_dump( struct object *obj, int verbose )
{
struct async *async = (struct async *)obj;
assert( obj->ops == &async_ops );
fprintf( stderr, "Async thread=%p\n", async->thread );
}
static void async_destroy( struct object *obj )
{
struct async *async = (struct async *)obj;
assert( obj->ops == &async_ops );
if (async->timeout) remove_timeout_user( async->timeout );
if (async->event) release_object( async->event );
release_object( async->thread );
}
/* notifies client thread of new status of its async request */
/* destroys the server side of it */
static void async_terminate( struct async *async, unsigned int status )
{
apc_call_t data;
memset( &data, 0, sizeof(data) );
data.type = APC_ASYNC_IO;
data.async_io.func = async->data.callback;
data.async_io.user = async->data.arg;
data.async_io.sb = async->data.iosb;
data.async_io.status = status;
thread_queue_apc( async->thread, &async->obj, &data );
if (async->timeout) remove_timeout_user( async->timeout );
async->timeout = NULL;
list_remove( &async->queue_entry );
release_object( async );
}
/* callback for timeout on an async request */
static void async_timeout( void *private )
{
struct async *async = private;
async->timeout = NULL;
async_terminate( async, STATUS_TIMEOUT );
}
/* create an async on a given queue of a fd */
struct async *create_async( struct thread *thread, const struct timeval *timeout,
struct list *queue, const async_data_t *data )
{
struct event *event = NULL;
struct async *async;
if (data->event && !(event = get_event_obj( thread->process, data->event, EVENT_MODIFY_STATE )))
return NULL;
if (!(async = alloc_object( &async_ops )))
{
if (event) release_object( event );
return NULL;
}
async->thread = (struct thread *)grab_object( thread );
async->event = event;
async->data = *data;
list_add_tail( queue, &async->queue_entry );
if (timeout) async->timeout = add_timeout_user( timeout, async_timeout, async );
else async->timeout = NULL;
if (event) reset_event( event );
return async;
}
/* store the result of the client-side async callback */
void async_set_result( struct object *obj, unsigned int status )
{
struct async *async = (struct async *)obj;
if (obj->ops != &async_ops) return; /* in case the client messed up the APC results */
if (status == STATUS_PENDING)
{
/* FIXME: restart the async operation */
}
else
{
if (async->event) set_event( async->event );
}
}
/* terminate the async operation at the head of the queue */
void async_terminate_head( struct list *queue, unsigned int status )
{
struct list *ptr = list_head( queue );
if (ptr) async_terminate( LIST_ENTRY( ptr, struct async, queue_entry ), status );
}
/* terminate all async operations on the queue */
void async_terminate_queue( struct list *queue, unsigned int status )
{
struct list *ptr, *next;
LIST_FOR_EACH_SAFE( ptr, next, queue )
{
struct async *async = LIST_ENTRY( ptr, struct async, queue_entry );
async_terminate( async, status );
}
}