1 files changed, 66 insertions, 0 deletions
diff --git a/lib/libc/gen/getmntinfo.c b/lib/libc/gen/getmntinfo.c
new file mode 100644
index 000000000000..3c224ef27d76
--- /dev/null
+++ b/lib/libc/gen/getmntinfo.c
@@ -0,0 +1,66 @@
+/*-
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ * Copyright (c) 1989, 1993
+ *	The Regents of the University of California.  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.
+ * 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.
+ * 3. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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/param.h>
+#include <sys/ucred.h>
+#include <sys/mount.h>
+#include <stdlib.h>
+
+#define	MAX_TRIES	3
+#define	SCALING_FACTOR	2
+
+/*
+ * Return information about mounted filesystems.
+ */
+int
+getmntinfo(struct statfs **mntbufp, int mode)
+{
+	static struct statfs *mntbuf;
+	static int mntsize;
+	static long bufsize;
+	unsigned tries = 0;
+
+	if (mntsize <= 0 && (mntsize = getfsstat(0, 0, MNT_NOWAIT)) < 0)
+		return (0);
+	if (bufsize > 0 && (mntsize = getfsstat(mntbuf, bufsize, mode)) < 0)
+		return (0);
+	while (tries++ < MAX_TRIES && bufsize <= mntsize * sizeof(*mntbuf)) {
+		bufsize = (mntsize * SCALING_FACTOR) * sizeof(*mntbuf);
+		if ((mntbuf = reallocf(mntbuf, bufsize)) == NULL)
+			return (0);
+		if ((mntsize = getfsstat(mntbuf, bufsize, mode)) < 0)
+			return (0);
+	}
+	*mntbufp = mntbuf;
+	if (mntsize > (bufsize / sizeof(*mntbuf)))
+		return (bufsize / sizeof(*mntbuf));
+	return (mntsize);
+}