include/cutils/fdevent.h

/*
 * Copyright (C) 2006 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef __FDEVENT_H
#define __FDEVENT_H

/* events that may be observed */
#define FDE_READ              0x0001
#define FDE_WRITE             0x0002
#define FDE_ERROR             0x0004

/* features that may be set (via the events set/add/del interface) */
#define FDE_DONT_CLOSE        0x0080

typedef struct fdevent fdevent;

typedef void (*fd_func)(int fd, unsigned events, void *userdata);

/* Allocate and initialize a new fdevent object
*/
fdevent *fdevent_create(int fd, fd_func func, void *arg);

/* Uninitialize and deallocate an fdevent object that was
** created by fdevent_create()
*/
void fdevent_destroy(fdevent *fde);

/* Initialize an fdevent object that was externally allocated
*/
void fdevent_install(fdevent *fde, int fd, fd_func func, void *arg);

/* Uninitialize an fdevent object that was initialized by
** fdevent_install()
*/
void fdevent_remove(fdevent *item);

/* Change which events should cause notifications
*/
void fdevent_set(fdevent *fde, unsigned events);
void fdevent_add(fdevent *fde, unsigned events);
void fdevent_del(fdevent *fde, unsigned events);

/* loop forever, handling events.
*/
void fdevent_loop();

struct fdevent 
{
    fdevent *next;
    fdevent *prev;

    int fd;
    unsigned short state;
    unsigned short events;
    
    fd_func func;
    void *arg;
};


#endif