--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/iobuf.c	Thu Mar 27 09:53:52 2014 +0500
@@ -0,0 +1,467 @@
+/*	$OpenBSD: iobuf.c,v 1.1 2014/01/27 15:49:52 sunil Exp $	*/
+
+/*      
+ * Copyright (c) 2012 Eric Faurot <eric@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/socket.h>
+#include <sys/uio.h>
+
+#include <errno.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#ifdef IO_SSL
+#include <openssl/err.h>
+#include <openssl/ssl.h>
+#endif
+
+#include "iobuf.h"
+
+#define IOBUF_MAX	65536
+#define IOBUFQ_MIN	4096
+
+struct ioqbuf	*ioqbuf_alloc(struct iobuf *, size_t);
+void		 iobuf_drain(struct iobuf *, size_t);
+
+int
+iobuf_init(struct iobuf *io, size_t size, size_t max)
+{
+	memset(io, 0, sizeof *io);
+
+	if (max == 0)
+		max = IOBUF_MAX;
+
+	if (size == 0)
+		size = max;
+
+	if (size > max)
+		return (-1);
+
+	if ((io->buf = malloc(size)) == NULL)
+		return (-1);
+
+	io->size = size;
+	io->max = max;
+
+	return (0);
+}
+
+void
+iobuf_clear(struct iobuf *io)
+{
+	struct ioqbuf	*q;
+
+	if (io->buf)
+		free(io->buf);
+
+	while ((q = io->outq)) {
+		io->outq = q->next;
+		free(q);
+	}
+
+	memset(io, 0, sizeof (*io));
+}
+
+void
+iobuf_drain(struct iobuf *io, size_t n)
+{
+	struct	ioqbuf	*q;
+	size_t		 left = n;
+
+	while ((q = io->outq) && left) {
+		if ((q->wpos - q->rpos) > left) {
+			q->rpos += left;
+			left = 0;
+		} else {
+			left -= q->wpos - q->rpos;
+			io->outq = q->next;
+			free(q);
+		}
+	}
+
+	io->queued -= (n - left);
+	if (io->outq == NULL)
+		io->outqlast = NULL;
+}
+
+int
+iobuf_extend(struct iobuf *io, size_t n)
+{
+	char	*t;
+
+	if (n > io->max)
+		return (-1);
+
+	if (io->max - io->size < n)
+		return (-1);
+
+	t = realloc(io->buf, io->size + n);
+	if (t == NULL)
+		return (-1);
+
+	io->size += n;
+	io->buf = t;
+
+	return (0);
+}
+
+size_t
+iobuf_left(struct iobuf *io)
+{
+	return io->size - io->wpos;
+}
+
+size_t
+iobuf_space(struct iobuf *io)
+{
+	return io->size - (io->wpos - io->rpos);
+}
+
+size_t
+iobuf_len(struct iobuf *io)
+{
+	return io->wpos - io->rpos;
+}
+
+char *
+iobuf_data(struct iobuf *io)
+{
+	return io->buf + io->rpos;
+}
+
+void
+iobuf_drop(struct iobuf *io, size_t n)
+{
+	if (n >= iobuf_len(io)) {
+		io->rpos = io->wpos = 0;
+		return;
+	}
+
+	io->rpos += n;
+}
+
+char *
+iobuf_getline(struct iobuf *iobuf, size_t *rlen)
+{
+	char	*buf;
+	size_t	 len, i;
+
+	buf = iobuf_data(iobuf);
+	len = iobuf_len(iobuf);
+
+	for (i = 0; i + 1 <= len; i++)
+		if (buf[i] == '\n') {
+			/* Note: the returned address points into the iobuf
+			 * buffer.  We NUL-end it for convenience, and discard
+			 * the data from the iobuf, so that the caller doesn't
+			 * have to do it.  The data remains "valid" as long
+			 * as the iobuf does not overwrite it, that is until
+			 * the next call to iobuf_normalize() or iobuf_extend().
+			 */
+			iobuf_drop(iobuf, i + 1);
+			len = (i && buf[i - 1] == '\r') ? i - 1 : i;
+			buf[len] = '\0';
+			if (rlen)
+				*rlen = len;
+			return (buf);
+		}
+
+	return (NULL);
+}
+
+void
+iobuf_normalize(struct iobuf *io)
+{
+	if (io->rpos == 0)
+		return;
+
+	if (io->rpos == io->wpos) {
+		io->rpos = io->wpos = 0;
+		return;
+	}
+
+	memmove(io->buf, io->buf + io->rpos, io->wpos - io->rpos);
+	io->wpos -= io->rpos;
+	io->rpos = 0;
+}
+
+ssize_t
+iobuf_read(struct iobuf *io, int fd)
+{
+	ssize_t	n;
+
+	n = read(fd, io->buf + io->wpos, iobuf_left(io));
+	if (n == -1) {
+		/* XXX is this really what we want? */
+		if (errno == EAGAIN || errno == EINTR)
+			return (IOBUF_WANT_READ);
+		return (IOBUF_ERROR);
+	}
+	if (n == 0)
+		return (IOBUF_CLOSED);
+
+	io->wpos += n;
+
+	return (n);
+}
+
+struct ioqbuf *
+ioqbuf_alloc(struct iobuf *io, size_t len)
+{
+	struct ioqbuf   *q;
+
+	if (len < IOBUFQ_MIN)
+		len = IOBUFQ_MIN;
+
+	if ((q = malloc(sizeof(*q) + len)) == NULL)
+		return (NULL);
+
+	q->rpos = 0;
+	q->wpos = 0;
+	q->size = len;
+	q->next = NULL;
+	q->buf = (char *)(q) + sizeof(*q);
+
+	if (io->outqlast == NULL)
+		io->outq = q;
+	else
+		io->outqlast->next = q;
+	io->outqlast = q;
+
+	return (q);
+}
+
+size_t
+iobuf_queued(struct iobuf *io)
+{
+	return io->queued;
+}
+
+void *
+iobuf_reserve(struct iobuf *io, size_t len)
+{
+	struct ioqbuf	*q;
+	void		*r;
+
+	if (len == 0)
+		return (NULL);
+
+	if (((q = io->outqlast) == NULL) || q->size - q->wpos <= len) {
+		if ((q = ioqbuf_alloc(io, len)) == NULL)
+			return (NULL);
+	}
+
+	r = q->buf + q->wpos;
+	q->wpos += len;
+	io->queued += len;
+
+	return (r);
+}
+
+int
+iobuf_queue(struct iobuf *io, const void *data, size_t len)
+{
+	void	*buf;
+
+	if (len == 0)
+		return (0);
+
+	if ((buf = iobuf_reserve(io, len)) == NULL)
+		return (-1);
+
+	memmove(buf, data, len);
+
+	return (0);
+}
+
+int
+iobuf_queuev(struct iobuf *io, const struct iovec *iov, int iovcnt)
+{
+	int	 i;
+	size_t	 len = 0;
+	char	*buf;
+
+	for (i = 0; i < iovcnt; i++)
+		len += iov[i].iov_len;
+
+	if ((buf = iobuf_reserve(io, len)) == NULL)
+		return (-1);
+
+	for (i = 0; i < iovcnt; i++) {
+		if (iov[i].iov_len == 0)
+			continue;
+		memmove(buf, iov[i].iov_base, iov[i].iov_len);
+		buf += iov[i].iov_len;
+	}
+
+	return (0);
+
+}
+
+int
+iobuf_fqueue(struct iobuf *io, const char *fmt, ...)
+{
+	va_list	ap;
+	int	len;
+
+	va_start(ap, fmt);
+	len = iobuf_vfqueue(io, fmt, ap);
+	va_end(ap);
+
+	return (len);
+}
+
+int
+iobuf_vfqueue(struct iobuf *io, const char *fmt, va_list ap)
+{
+	char	*buf;
+	int	 len;
+
+	len = vasprintf(&buf, fmt, ap);
+
+	if (len == -1)
+		return (-1);
+
+	len = iobuf_queue(io, buf, len);
+	free(buf);
+
+	return (len);
+}
+
+ssize_t
+iobuf_write(struct iobuf *io, int fd)
+{
+	struct iovec	 iov[IOV_MAX];
+	struct ioqbuf	*q;
+	int		 i;
+	ssize_t		 n;
+
+	i = 0;
+	for (q = io->outq; q ; q = q->next) {
+		if (i >= IOV_MAX)
+			break;
+		iov[i].iov_base = q->buf + q->rpos;
+		iov[i].iov_len = q->wpos - q->rpos;
+		i++;
+	}
+
+	n = writev(fd, iov, i);
+	if (n == -1) {
+		if (errno == EAGAIN || errno == EINTR)
+			return (IOBUF_WANT_WRITE);
+		if (errno == EPIPE)
+			return (IOBUF_CLOSED);
+		return (IOBUF_ERROR);
+	}
+
+	iobuf_drain(io, n);
+
+	return (n);
+}
+
+int
+iobuf_flush(struct iobuf *io, int fd)
+{
+	ssize_t	s;
+
+	while (io->queued)
+		if ((s = iobuf_write(io, fd)) < 0)
+			return (s);
+
+	return (0);
+}
+
+#ifdef IO_SSL
+
+int
+iobuf_flush_ssl(struct iobuf *io, void *ssl)
+{
+	ssize_t	s;
+
+	while (io->queued)
+		if ((s = iobuf_write_ssl(io, ssl) < 0))
+			return (s);
+
+	return (0);
+}
+
+ssize_t
+iobuf_write_ssl(struct iobuf *io, void *ssl)
+{
+	struct ioqbuf	*q;
+	int		 r;
+	ssize_t		 n;
+
+	q = io->outq;
+	n = SSL_write(ssl, q->buf + q->rpos, q->wpos - q->rpos);
+	if (n <= 0) {
+		switch ((r = SSL_get_error(ssl, n))) {
+		case SSL_ERROR_WANT_READ:
+			return (IOBUF_WANT_READ);
+		case SSL_ERROR_WANT_WRITE:
+			return (IOBUF_WANT_WRITE);
+		case SSL_ERROR_ZERO_RETURN: /* connection closed */
+			return (IOBUF_CLOSED);
+		case SSL_ERROR_SYSCALL:
+			if (ERR_peek_last_error())
+				return (IOBUF_SSLERROR);
+			if (r == 0)
+				errno = EPIPE;
+			return (IOBUF_ERROR);
+		default:
+			return (IOBUF_SSLERROR);
+		}
+	}
+	iobuf_drain(io, n);
+
+	return (n);
+}
+
+ssize_t
+iobuf_read_ssl(struct iobuf *io, void *ssl)
+{
+	ssize_t	n;
+	int	r;
+
+	n = SSL_read(ssl, io->buf + io->wpos, iobuf_left(io));
+	if (n < 0) {
+		switch ((r = SSL_get_error(ssl, n))) {
+		case SSL_ERROR_WANT_READ:
+			return (IOBUF_WANT_READ);
+		case SSL_ERROR_WANT_WRITE:
+			return (IOBUF_WANT_WRITE);
+		case SSL_ERROR_SYSCALL:
+			if (ERR_peek_last_error())
+				return (IOBUF_SSLERROR);
+			if (r == 0)
+				errno = EPIPE;
+			return (IOBUF_ERROR);
+		default:
+			return (IOBUF_SSLERROR);
+		}
+	} else if (n == 0)
+		return (IOBUF_CLOSED);
+
+	io->wpos += n;
+
+	return (n);
+}
+
+#endif /* IO_SSL */