diff options
Diffstat (limited to 'usr.sbin/dvmrpd/buffer.c')
| -rw-r--r-- | usr.sbin/dvmrpd/buffer.c | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/usr.sbin/dvmrpd/buffer.c b/usr.sbin/dvmrpd/buffer.c new file mode 100644 index 00000000000..751e0ac45eb --- /dev/null +++ b/usr.sbin/dvmrpd/buffer.c @@ -0,0 +1,218 @@ +/* $OpenBSD: buffer.c,v 1.1 2006/06/01 14:12:20 norby 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/types.h> +#include <sys/uio.h> + +#include <errno.h> +#include <limits.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +#include "dvmrpd.h" + +int buf_realloc(struct buf *, size_t); +void buf_enqueue(struct msgbuf *, struct buf *); +void buf_dequeue(struct msgbuf *, struct buf *); + +struct buf * +buf_open(size_t len) +{ + struct buf *buf; + + if ((buf = calloc(1, sizeof(struct buf))) == NULL) + return (NULL); + if ((buf->buf = malloc(len)) == NULL) { + free(buf); + return (NULL); + } + buf->size = buf->max = len; + + return (buf); +} + +struct buf * +buf_dynamic(size_t len, size_t max) +{ + struct buf *buf; + + if (max < len) + return (NULL); + + if ((buf = buf_open(len)) == NULL) + return (NULL); + + if (max > 0) + buf->max = max; + + return (buf); +} + +int +buf_realloc(struct buf *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 +buf_add(struct buf *buf, void *data, size_t len) +{ + if (buf->wpos + len > buf->size) + if (buf_realloc(buf, len) == -1) + return (-1); + + memcpy(buf->buf + buf->wpos, data, len); + buf->wpos += len; + return (0); +} + +void * +buf_reserve(struct buf *buf, size_t len) +{ + void *b; + + if (buf->wpos + len > buf->size) + if (buf_realloc(buf, len) == -1) + return (NULL); + + b = buf->buf + buf->wpos; + buf->wpos += len; + return (b); +} + +void * +buf_seek(struct buf *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); +} + +int +buf_close(struct msgbuf *msgbuf, struct buf *buf) +{ + buf_enqueue(msgbuf, buf); + return (1); +} + +void +buf_free(struct buf *buf) +{ + free(buf->buf); + free(buf); +} + +void +msgbuf_init(struct msgbuf *msgbuf) +{ + msgbuf->queued = 0; + msgbuf->fd = -1; + TAILQ_INIT(&msgbuf->bufs); +} + +void +msgbuf_clear(struct msgbuf *msgbuf) +{ + struct buf *buf; + + while ((buf = TAILQ_FIRST(&msgbuf->bufs)) != NULL) + buf_dequeue(msgbuf, buf); +} + +int +msgbuf_write(struct msgbuf *msgbuf) +{ + struct iovec iov[IOV_MAX]; + struct buf *buf, *next; + int i = 0; + ssize_t n; + struct msghdr msg; + + 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->size - buf->rpos; + i++; + } + + msg.msg_iov = iov; + msg.msg_iovlen = i; + + if ((n = sendmsg(msgbuf->fd, &msg, 0)) == -1) { + if (errno == EAGAIN || errno == ENOBUFS || + errno == EINTR) /* try later */ + return (0); + else + return (-1); + } + + if (n == 0) { /* connection closed */ + errno = 0; + return (-2); + } + + for (buf = TAILQ_FIRST(&msgbuf->bufs); buf != NULL && n > 0; + buf = next) { + next = TAILQ_NEXT(buf, entry); + if (buf->rpos + n >= buf->size) { + n -= buf->size - buf->rpos; + buf_dequeue(msgbuf, buf); + } else { + buf->rpos += n; + n = 0; + } + } + + return (0); +} + +void +buf_enqueue(struct msgbuf *msgbuf, struct buf *buf) +{ + TAILQ_INSERT_TAIL(&msgbuf->bufs, buf, entry); + msgbuf->queued++; +} + +void +buf_dequeue(struct msgbuf *msgbuf, struct buf *buf) +{ + TAILQ_REMOVE(&msgbuf->bufs, buf, entry); + msgbuf->queued--; + buf_free(buf); +} |