Index: openbsd-compat/imsg-buffer.c
===================================================================
RCS file: openbsd-compat/imsg-buffer.c
diff -N openbsd-compat/imsg-buffer.c
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ openbsd-compat/imsg-buffer.c 8 Dec 2012 20:17:59 -0000 1.2
@@ -0,0 +1,305 @@
+/* $OpenBSD: imsg-buffer.c,v 1.1 2010/05/26 16:44:32 nicm Exp $ */
+
+/*
+ * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/param.h>
+#include <sys/queue.h>
+#include <sys/socket.h>
+#include <sys/uio.h>
+
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "imsg.h"
+
+int ibuf_realloc(struct ibuf *, size_t);
+void ibuf_enqueue(struct msgbuf *, struct ibuf *);
+void ibuf_dequeue(struct msgbuf *, struct ibuf *);
+
+struct ibuf *
+ibuf_open(size_t len)
+{
+ struct ibuf *buf;
+
+ if ((buf = calloc(1, sizeof(struct ibuf))) == NULL)
+ return (NULL);
+ if ((buf->buf = malloc(len)) == NULL) {
+ free(buf);
+ return (NULL);
+ }
+ buf->size = buf->max = len;
+ buf->fd = -1;
+
+ return (buf);
+}
+
+struct ibuf *
+ibuf_dynamic(size_t len, size_t max)
+{
+ struct ibuf *buf;
+
+ if (max < len)
+ return (NULL);
+
+ if ((buf = ibuf_open(len)) == NULL)
+ return (NULL);
+
+ if (max > 0)
+ buf->max = max;
+
+ return (buf);
+}
+
+int
+ibuf_realloc(struct ibuf *buf, size_t len)
+{
+ u_char *b;
+
+ /* on static buffers max is eq size and so the following fails */
+ if (buf->wpos + len > buf->max) {
+ errno = ENOMEM;
+ return (-1);
+ }
+
+ b = realloc(buf->buf, buf->wpos + len);
+ if (b == NULL)
+ return (-1);
+ buf->buf = b;
+ buf->size = buf->wpos + len;
+
+ return (0);
+}
+
+int
+ibuf_add(struct ibuf *buf, const void *data, size_t len)
+{
+ if (buf->wpos + len > buf->size)
+ if (ibuf_realloc(buf, len) == -1)
+ return (-1);
+
+ memcpy(buf->buf + buf->wpos, data, len);
+ buf->wpos += len;
+ return (0);
+}
+
+void *
+ibuf_reserve(struct ibuf *buf, size_t len)
+{
+ void *b;
+
+ if (buf->wpos + len > buf->size)
+ if (ibuf_realloc(buf, len) == -1)
+ return (NULL);
+
+ b = buf->buf + buf->wpos;
+ buf->wpos += len;
+ return (b);
+}
+
+void *
+ibuf_seek(struct ibuf *buf, size_t pos, size_t len)
+{
+ /* only allowed to seek in already written parts */
+ if (pos + len > buf->wpos)
+ return (NULL);
+
+ return (buf->buf + pos);
+}
+
+size_t
+ibuf_size(struct ibuf *buf)
+{
+ return (buf->wpos);
+}
+
+size_t
+ibuf_left(struct ibuf *buf)
+{
+ return (buf->max - buf->wpos);
+}
+
+void
+ibuf_close(struct msgbuf *msgbuf, struct ibuf *buf)
+{
+ ibuf_enqueue(msgbuf, buf);
+}
+
+int
+ibuf_write(struct msgbuf *msgbuf)
+{
+ struct iovec iov[IOV_MAX];
+ struct ibuf *buf;
+ unsigned int i = 0;
+ ssize_t n;
+
+ bzero(&iov, sizeof(iov));
+ TAILQ_FOREACH(buf, &msgbuf->bufs, entry) {
+ if (i >= IOV_MAX)
+ break;
+ iov[i].iov_base = buf->buf + buf->rpos;
+ iov[i].iov_len = buf->wpos - buf->rpos;
+ i++;
+ }
+
+again:
+ if ((n = writev(msgbuf->fd, iov, i)) == -1) {
+ if (errno == EAGAIN || errno == EINTR)
+ goto again;
+ if (errno == ENOBUFS)
+ errno = EAGAIN;
+ return (-1);
+ }
+
+ if (n == 0) { /* connection closed */
+ errno = 0;
+ return (0);
+ }
+
+ msgbuf_drain(msgbuf, n);
+
+ return (1);
+}
+
+void
+ibuf_free(struct ibuf *buf)
+{
+ free(buf->buf);
+ free(buf);
+}
+
+void
+msgbuf_init(struct msgbuf *msgbuf)
+{
+ msgbuf->queued = 0;
+ msgbuf->fd = -1;
+ TAILQ_INIT(&msgbuf->bufs);
+}
+
+void
+msgbuf_drain(struct msgbuf *msgbuf, size_t n)
+{
+ struct ibuf *buf, *next;
+
+ for (buf = TAILQ_FIRST(&msgbuf->bufs); buf != NULL && n > 0;
+ buf = next) {
+ next = TAILQ_NEXT(buf, entry);
+ if (buf->rpos + n >= buf->wpos) {
+ n -= buf->wpos - buf->rpos;
+ ibuf_dequeue(msgbuf, buf);
+ } else {
+ buf->rpos += n;
+ n = 0;
+ }
+ }
+}
+
+void
+msgbuf_clear(struct msgbuf *msgbuf)
+{
+ struct ibuf *buf;
+
+ while ((buf = TAILQ_FIRST(&msgbuf->bufs)) != NULL)
+ ibuf_dequeue(msgbuf, buf);
+}
+
+int
+msgbuf_write(struct msgbuf *msgbuf)
+{
+ struct iovec iov[IOV_MAX];
+ struct ibuf *buf;
+ unsigned int i = 0;
+ ssize_t n;
+ struct msghdr msg;
+ struct cmsghdr *cmsg;
+ union {
+ struct cmsghdr hdr;
+ char buf[CMSG_SPACE(sizeof(int))];
+ } cmsgbuf;
+
+ bzero(&iov, sizeof(iov));
+ bzero(&msg, sizeof(msg));
+ TAILQ_FOREACH(buf, &msgbuf->bufs, entry) {
+ if (i >= IOV_MAX)
+ break;
+ iov[i].iov_base = buf->buf + buf->rpos;
+ iov[i].iov_len = buf->wpos - buf->rpos;
+ i++;
+ if (buf->fd != -1)
+ break;
+ }
+
+ msg.msg_iov = iov;
+ msg.msg_iovlen = i;
+
+ if (buf != NULL && buf->fd != -1) {
+ msg.msg_control = (caddr_t)&cmsgbuf.buf;
+ msg.msg_controllen = sizeof(cmsgbuf.buf);
+ cmsg = CMSG_FIRSTHDR(&msg);
+ cmsg->cmsg_len = CMSG_LEN(sizeof(int));
+ cmsg->cmsg_level = SOL_SOCKET;
+ cmsg->cmsg_type = SCM_RIGHTS;
+ *(int *)CMSG_DATA(cmsg) = buf->fd;
+ }
+
+again:
+ if ((n = sendmsg(msgbuf->fd, &msg, 0)) == -1) {
+ if (errno == EAGAIN || errno == EINTR)
+ goto again;
+ if (errno == ENOBUFS)
+ errno = EAGAIN;
+ return (-1);
+ }
+
+ if (n == 0) { /* connection closed */
+ errno = 0;
+ return (0);
+ }
+
+ /*
+ * assumption: fd got sent if sendmsg sent anything
+ * this works because fds are passed one at a time
+ */
+ if (buf != NULL && buf->fd != -1) {
+ close(buf->fd);
+ buf->fd = -1;
+ }
+
+ msgbuf_drain(msgbuf, n);
+
+ return (1);
+}
+
+void
+ibuf_enqueue(struct msgbuf *msgbuf, struct ibuf *buf)
+{
+ TAILQ_INSERT_TAIL(&msgbuf->bufs, buf, entry);
+ msgbuf->queued++;
+}
+
+void
+ibuf_dequeue(struct msgbuf *msgbuf, struct ibuf *buf)
+{
+ TAILQ_REMOVE(&msgbuf->bufs, buf, entry);
+
+ if (buf->fd != -1)
+ close(buf->fd);
+
+ msgbuf->queued--;
+ ibuf_free(buf);
+}