GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: lib/libutil/imsg.c Lines: 0 124 0.0 %
Date: 2017-11-13 Branches: 0 72 0.0 %

Line Branch Exec Source
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/*	$OpenBSD: imsg.c,v 1.15 2017/04/11 09:57:19 reyk Exp $	*/
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/*
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 * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
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 *
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 * Permission to use, copy, modify, and distribute this software for any
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 * purpose with or without fee is hereby granted, provided that the above
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 * copyright notice and this permission notice appear in all copies.
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 *
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 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
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 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
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 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
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 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
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 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
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 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
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 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
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 */
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#include <sys/types.h>
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#include <sys/queue.h>
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#include <sys/socket.h>
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#include <sys/uio.h>
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#include <errno.h>
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#include <stdlib.h>
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#include <string.h>
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#include <unistd.h>
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#include "imsg.h"
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int	 imsg_fd_overhead = 0;
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int	 imsg_get_fd(struct imsgbuf *);
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void
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imsg_init(struct imsgbuf *ibuf, int fd)
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{
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	msgbuf_init(&ibuf->w);
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	memset(&ibuf->r, 0, sizeof(ibuf->r));
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	ibuf->fd = fd;
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	ibuf->w.fd = fd;
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	ibuf->pid = getpid();
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	TAILQ_INIT(&ibuf->fds);
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}
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ssize_t
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imsg_read(struct imsgbuf *ibuf)
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{
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	struct msghdr		 msg;
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	struct cmsghdr		*cmsg;
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	union {
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		struct cmsghdr hdr;
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		char	buf[CMSG_SPACE(sizeof(int) * 1)];
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	} cmsgbuf;
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	struct iovec		 iov;
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	ssize_t			 n = -1;
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	int			 fd;
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	struct imsg_fd		*ifd;
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	memset(&msg, 0, sizeof(msg));
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	memset(&cmsgbuf, 0, sizeof(cmsgbuf));
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	iov.iov_base = ibuf->r.buf + ibuf->r.wpos;
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	iov.iov_len = sizeof(ibuf->r.buf) - ibuf->r.wpos;
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	msg.msg_iov = &iov;
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	msg.msg_iovlen = 1;
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	msg.msg_control = &cmsgbuf.buf;
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	msg.msg_controllen = sizeof(cmsgbuf.buf);
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	if ((ifd = calloc(1, sizeof(struct imsg_fd))) == NULL)
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		return (-1);
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again:
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	if (getdtablecount() + imsg_fd_overhead +
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	    (int)((CMSG_SPACE(sizeof(int))-CMSG_SPACE(0))/sizeof(int))
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	    >= getdtablesize()) {
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		errno = EAGAIN;
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		free(ifd);
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		return (-1);
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	}
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	if ((n = recvmsg(ibuf->fd, &msg, 0)) == -1) {
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		if (errno == EINTR)
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			goto again;
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		goto fail;
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	}
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	ibuf->r.wpos += n;
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	for (cmsg = CMSG_FIRSTHDR(&msg); cmsg != NULL;
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	    cmsg = CMSG_NXTHDR(&msg, cmsg)) {
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		if (cmsg->cmsg_level == SOL_SOCKET &&
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		    cmsg->cmsg_type == SCM_RIGHTS) {
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			int i;
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			int j;
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			/*
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			 * We only accept one file descriptor.  Due to C
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			 * padding rules, our control buffer might contain
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			 * more than one fd, and we must close them.
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			 */
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			j = ((char *)cmsg + cmsg->cmsg_len -
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			    (char *)CMSG_DATA(cmsg)) / sizeof(int);
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			for (i = 0; i < j; i++) {
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				fd = ((int *)CMSG_DATA(cmsg))[i];
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				if (ifd != NULL) {
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					ifd->fd = fd;
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					TAILQ_INSERT_TAIL(&ibuf->fds, ifd,
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					    entry);
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					ifd = NULL;
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				} else
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					close(fd);
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			}
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		}
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		/* we do not handle other ctl data level */
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	}
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fail:
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	free(ifd);
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	return (n);
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}
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ssize_t
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imsg_get(struct imsgbuf *ibuf, struct imsg *imsg)
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{
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	size_t			 av, left, datalen;
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	av = ibuf->r.wpos;
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	if (IMSG_HEADER_SIZE > av)
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		return (0);
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	memcpy(&imsg->hdr, ibuf->r.buf, sizeof(imsg->hdr));
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	if (imsg->hdr.len < IMSG_HEADER_SIZE ||
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	    imsg->hdr.len > MAX_IMSGSIZE) {
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		errno = ERANGE;
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		return (-1);
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	}
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	if (imsg->hdr.len > av)
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		return (0);
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	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
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	ibuf->r.rptr = ibuf->r.buf + IMSG_HEADER_SIZE;
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	if (datalen == 0)
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		imsg->data = NULL;
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	else if ((imsg->data = malloc(datalen)) == NULL)
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		return (-1);
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	if (imsg->hdr.flags & IMSGF_HASFD)
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		imsg->fd = imsg_get_fd(ibuf);
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	else
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		imsg->fd = -1;
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	memcpy(imsg->data, ibuf->r.rptr, datalen);
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	if (imsg->hdr.len < av) {
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		left = av - imsg->hdr.len;
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		memmove(&ibuf->r.buf, ibuf->r.buf + imsg->hdr.len, left);
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		ibuf->r.wpos = left;
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	} else
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		ibuf->r.wpos = 0;
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	return (datalen + IMSG_HEADER_SIZE);
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}
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int
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imsg_compose(struct imsgbuf *ibuf, uint32_t type, uint32_t peerid, pid_t pid,
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    int fd, const void *data, uint16_t datalen)
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{
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	struct ibuf	*wbuf;
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	if ((wbuf = imsg_create(ibuf, type, peerid, pid, datalen)) == NULL)
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		return (-1);
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	if (imsg_add(wbuf, data, datalen) == -1)
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		return (-1);
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	wbuf->fd = fd;
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	imsg_close(ibuf, wbuf);
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	return (1);
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}
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int
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imsg_composev(struct imsgbuf *ibuf, uint32_t type, uint32_t peerid, pid_t pid,
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    int fd, const struct iovec *iov, int iovcnt)
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{
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	struct ibuf	*wbuf;
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	int		 i, datalen = 0;
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	for (i = 0; i < iovcnt; i++)
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		datalen += iov[i].iov_len;
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	if ((wbuf = imsg_create(ibuf, type, peerid, pid, datalen)) == NULL)
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		return (-1);
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	for (i = 0; i < iovcnt; i++)
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		if (imsg_add(wbuf, iov[i].iov_base, iov[i].iov_len) == -1)
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			return (-1);
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	wbuf->fd = fd;
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	imsg_close(ibuf, wbuf);
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	return (1);
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}
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/* ARGSUSED */
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struct ibuf *
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imsg_create(struct imsgbuf *ibuf, uint32_t type, uint32_t peerid, pid_t pid,
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    uint16_t datalen)
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{
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	struct ibuf	*wbuf;
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	struct imsg_hdr	 hdr;
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	datalen += IMSG_HEADER_SIZE;
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	if (datalen > MAX_IMSGSIZE) {
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		errno = ERANGE;
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		return (NULL);
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	}
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	hdr.type = type;
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	hdr.flags = 0;
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	hdr.peerid = peerid;
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	if ((hdr.pid = pid) == 0)
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		hdr.pid = ibuf->pid;
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	if ((wbuf = ibuf_dynamic(datalen, MAX_IMSGSIZE)) == NULL) {
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		return (NULL);
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	}
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	if (imsg_add(wbuf, &hdr, sizeof(hdr)) == -1)
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		return (NULL);
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	return (wbuf);
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}
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int
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imsg_add(struct ibuf *msg, const void *data, uint16_t datalen)
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{
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	if (datalen)
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		if (ibuf_add(msg, data, datalen) == -1) {
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			ibuf_free(msg);
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			return (-1);
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		}
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	return (datalen);
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}
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void
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imsg_close(struct imsgbuf *ibuf, struct ibuf *msg)
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{
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	struct imsg_hdr	*hdr;
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	hdr = (struct imsg_hdr *)msg->buf;
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	hdr->flags &= ~IMSGF_HASFD;
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	if (msg->fd != -1)
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		hdr->flags |= IMSGF_HASFD;
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	hdr->len = (uint16_t)msg->wpos;
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	ibuf_close(&ibuf->w, msg);
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}
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void
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imsg_free(struct imsg *imsg)
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{
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	freezero(imsg->data, imsg->hdr.len - IMSG_HEADER_SIZE);
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}
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int
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imsg_get_fd(struct imsgbuf *ibuf)
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{
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	int		 fd;
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	struct imsg_fd	*ifd;
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	if ((ifd = TAILQ_FIRST(&ibuf->fds)) == NULL)
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		return (-1);
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	fd = ifd->fd;
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	TAILQ_REMOVE(&ibuf->fds, ifd, entry);
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	free(ifd);
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	return (fd);
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}
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int
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imsg_flush(struct imsgbuf *ibuf)
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{
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	while (ibuf->w.queued)
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		if (msgbuf_write(&ibuf->w) <= 0)
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			return (-1);
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	return (0);
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}
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void
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imsg_clear(struct imsgbuf *ibuf)
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{
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	int	fd;
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	msgbuf_clear(&ibuf->w);
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	while ((fd = imsg_get_fd(ibuf)) != -1)
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		close(fd);
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}