1 files changed, 141 insertions, 0 deletions
diff --git a/usr/src/cmd/bhyve/iov.c b/usr/src/cmd/bhyve/iov.c
new file mode 100644
index 0000000000..c564bd8ae5
--- /dev/null
+++ b/usr/src/cmd/bhyve/iov.c
@@ -0,0 +1,141 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
+ *
+ * Copyright (c) 2016 Jakub Klama <jceel@FreeBSD.org>.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer
+ *    in this position and unchanged.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/types.h>
+#include <sys/uio.h>
+
+#include <stdlib.h>
+#include <string.h>
+#include "iov.h"
+
+void
+seek_iov(struct iovec *iov1, size_t niov1, struct iovec *iov2, size_t *niov2,
+    size_t seek)
+{
+	size_t remainder = 0;
+	size_t left = seek;
+	size_t i, j;
+
+	for (i = 0; i < niov1; i++) {
+		size_t toseek = MIN(left, iov1[i].iov_len);
+		left -= toseek;
+
+		if (toseek == iov1[i].iov_len)
+			continue;
+
+		if (left == 0) {
+			remainder = toseek;
+			break;
+		}
+	}
+
+	for (j = i; j < niov1; j++) {
+		iov2[j - i].iov_base = (char *)iov1[j].iov_base + remainder;
+		iov2[j - i].iov_len = iov1[j].iov_len - remainder;
+		remainder = 0;
+	}
+
+	*niov2 = j - i;
+}
+
+size_t
+count_iov(struct iovec *iov, size_t niov)
+{
+	size_t i, total = 0;
+
+	for (i = 0; i < niov; i++)
+		total += iov[i].iov_len;
+
+	return (total);
+}
+
+size_t
+truncate_iov(struct iovec *iov, size_t niov, size_t length)
+{
+	size_t i, done = 0;
+
+	for (i = 0; i < niov; i++) {
+		size_t toseek = MIN(length - done, iov[i].iov_len);
+		done += toseek;
+
+		if (toseek < iov[i].iov_len) {
+			iov[i].iov_len = toseek;
+			return (i + 1);
+		}
+	}
+
+	return (niov);
+}
+
+ssize_t
+iov_to_buf(struct iovec *iov, size_t niov, void **buf)
+{
+	size_t i, ptr = 0, total = 0;
+
+	for (i = 0; i < niov; i++) {
+		total += iov[i].iov_len;
+		*buf = realloc(*buf, total);
+		if (*buf == NULL)
+			return (-1);
+
+		memcpy(*buf + ptr, iov[i].iov_base, iov[i].iov_len);
+		ptr += iov[i].iov_len;
+	}
+
+	return (total);
+}
+
+ssize_t
+buf_to_iov(void *buf, size_t buflen, struct iovec *iov, size_t niov,
+    size_t seek)
+{
+	struct iovec *diov;
+	size_t ndiov, i;
+	uintptr_t off = 0;
+
+	if (seek > 0) {
+		diov = malloc(sizeof(struct iovec) * niov);
+		seek_iov(iov, niov, diov, &ndiov, seek);
+	} else {
+		diov = iov;
+		ndiov = niov;
+	}
+
+	for (i = 0; i < ndiov; i++) {
+		memcpy(diov[i].iov_base, buf + off, diov[i].iov_len);
+		off += diov[i].iov_len;
+	}
+
+	return ((ssize_t)off);
+}
+