| 1 |  |  | /*	$OpenBSD: imsg_subr.c,v 1.1 2015/07/21 04:06:04 yasuoka Exp $	*/ | 
    
    | 2 |  |  |  | 
    
    | 3 |  |  | /* | 
    
    | 4 |  |  |  * Copyright (c) 2015 YASUOKA Masahiko <yasuoka@yasuoka.net> | 
    
    | 5 |  |  |  * | 
    
    | 6 |  |  |  * Permission to use, copy, modify, and distribute this software for any | 
    
    | 7 |  |  |  * purpose with or without fee is hereby granted, provided that the above | 
    
    | 8 |  |  |  * copyright notice and this permission notice appear in all copies. | 
    
    | 9 |  |  |  * | 
    
    | 10 |  |  |  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES | 
    
    | 11 |  |  |  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF | 
    
    | 12 |  |  |  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR | 
    
    | 13 |  |  |  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES | 
    
    | 14 |  |  |  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN | 
    
    | 15 |  |  |  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF | 
    
    | 16 |  |  |  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. | 
    
    | 17 |  |  |  */ | 
    
    | 18 |  |  | #include <sys/types.h> | 
    
    | 19 |  |  | #include <sys/queue.h> | 
    
    | 20 |  |  | #include <sys/uio.h> | 
    
    | 21 |  |  |  | 
    
    | 22 |  |  | #include <imsg.h> | 
    
    | 23 |  |  | #include <stdarg.h> | 
    
    | 24 |  |  | #include <stdio.h> | 
    
    | 25 |  |  | #include <string.h> | 
    
    | 26 |  |  | #include <poll.h> | 
    
    | 27 |  |  | #include <errno.h> | 
    
    | 28 |  |  |  | 
    
    | 29 |  |  | #include "imsg_subr.h" | 
    
    | 30 |  |  |  | 
    
    | 31 |  |  | /* | 
    
    | 32 |  |  |  * Check readability not to spin before calling imsg_read(3).  Wait 'millisec' | 
    
    | 33 |  |  |  * until it becomes readable. | 
    
    | 34 |  |  |  */ | 
    
    | 35 |  |  | int | 
    
    | 36 |  |  | imsg_sync_read(struct imsgbuf *ibuf, int millisec) | 
    
    | 37 |  |  | { | 
    
    | 38 |  |  | 	struct pollfd	 fds[1]; | 
    
    | 39 |  |  | 	int		 retval; | 
    
    | 40 |  |  |  | 
    
    | 41 |  |  | 	fds[0].fd = ibuf->fd; | 
    
    | 42 |  |  | 	fds[0].events = POLLIN; | 
    
    | 43 |  |  | 	retval = poll(fds, 1, millisec); | 
    
    | 44 |  |  | 	if (retval == 0) { | 
    
    | 45 |  |  | 		errno = EAGAIN; | 
    
    | 46 |  |  | 		return (-1); | 
    
    | 47 |  |  | 	} | 
    
    | 48 |  |  | 	if (retval > 0 && (fds[0].revents & POLLIN) != 0) | 
    
    | 49 |  |  | 		return imsg_read(ibuf); | 
    
    | 50 |  |  |  | 
    
    | 51 |  |  | 	return (-1); | 
    
    | 52 |  |  | } | 
    
    | 53 |  |  |  | 
    
    | 54 |  |  | /* | 
    
    | 55 |  |  |  * Check writability not to spin before calling imsg_flush(3).  Wait 'millisec' | 
    
    | 56 |  |  |  * until it becomes writable. | 
    
    | 57 |  |  |  */ | 
    
    | 58 |  |  | int | 
    
    | 59 |  |  | imsg_sync_flush(struct imsgbuf *ibuf, int millisec) | 
    
    | 60 |  |  | { | 
    
    | 61 |  |  | 	struct pollfd	 fds[1]; | 
    
    | 62 |  |  | 	int		 retval; | 
    
    | 63 |  |  |  | 
    
    | 64 |  |  | 	if (!ibuf->w.queued) | 
    
    | 65 |  |  | 		return (0);	/* already flushed */ | 
    
    | 66 |  |  |  | 
    
    | 67 |  |  | 	fds[0].fd = ibuf->fd; | 
    
    | 68 |  |  | 	fds[0].events = POLLOUT; | 
    
    | 69 |  |  | 	retval = poll(fds, 1, millisec); | 
    
    | 70 |  |  | 	if (retval == 0) { | 
    
    | 71 |  |  | 		errno = EAGAIN; | 
    
    | 72 |  |  | 		return (-1); | 
    
    | 73 |  |  | 	} | 
    
    | 74 |  |  | 	if (retval > 0 && (fds[0].revents & POLLOUT) != 0) | 
    
    | 75 |  |  | 		return imsg_flush(ibuf); | 
    
    | 76 |  |  |  | 
    
    | 77 |  |  | 	return (-1); | 
    
    | 78 |  |  | } |