Switch to NetBSD utmp.c.

Change-Id: Ibe94888aa48b5b28fea97fd5719a1ed7a23ddeb3

libc/upstream-netbsd/lib/libc/gen/utmp.c

@@ -0,0 +1,106 @@
+/*	$NetBSD: utmp.c,v 1.10 2011/10/15 23:00:02 christos Exp $	 */
+
+/*-
+ * Copyright (c) 2002 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to The NetBSD Foundation
+ * by Christos Zoulas.
+ *
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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>
+
+#if defined(LIBC_SCCS) && !defined(lint)
+__RCSID("$NetBSD: utmp.c,v 1.10 2011/10/15 23:00:02 christos Exp $");
+#endif /* LIBC_SCCS and not lint */
+
+#include "namespace.h"
+#include <sys/types.h>
+#include <sys/param.h>
+#include <stdio.h>
+#include <string.h>
+#include <time.h>
+#include <utmp.h>
+#include <sys/stat.h>
+
+static struct utmp utmp;
+static FILE *ut;
+static char utfile[MAXPATHLEN] = _PATH_UTMP;
+
+void
+setutent(void)
+{
+	if (ut == NULL)
+		return;
+	(void)fseeko(ut, (off_t)0, SEEK_SET);
+}
+
+struct utmp *
+getutent(void)
+{
+	if (ut == NULL) {
+		struct stat st;
+		off_t numentries;
+		if ((ut = fopen(utfile, "re")) == NULL)
+			return NULL;
+		if (fstat(fileno(ut), &st) == -1)
+			goto out;
+		/*
+		 * If we have a an old version utmp file bail.
+		 */
+		numentries = st.st_size / sizeof(utmp);
+		if ((off_t)(numentries * sizeof(utmp)) != st.st_size)
+			goto out;
+	}
+	if (fread(&utmp, sizeof(utmp), 1, ut) == 1)
+		return &utmp;
+out:
+	(void)fclose(ut);
+	return NULL;
+}
+
+void
+endutent(void)
+{
+	if (ut != NULL) {
+		(void)fclose(ut);
+		ut = NULL;
+	}
+}
+
+int
+utmpname(const char *fname)
+{
+	size_t len = strlen(fname);
+
+	if (len >= sizeof(utfile))
+		return 0;
+
+	/* must not end in x! */
+	if (fname[len - 1] == 'x')
+		return 0;
+
+	(void)strlcpy(utfile, fname, sizeof(utfile));
+	endutent();
+	return 1;
+}