1 files changed, 120 insertions, 0 deletions
diff --git a/system_cmds/vifs.tproj/vifs.c b/system_cmds/vifs.tproj/vifs.c
new file mode 100644
index 0000000..967cc1d
--- /dev/null
+++ b/system_cmds/vifs.tproj/vifs.c
@@ -0,0 +1,120 @@
+/*
+ * Copyright (c) 2005-2016 Apple Inc. All rights reserved.
+ *
+ * @APPLE_LICENSE_HEADER_START@
+ *
+ * The contents of this file constitute Original Code as defined in and
+ * are subject to the Apple Public Source License Version 1.1 (the
+ * "License").  You may not use this file except in compliance with the
+ * License.  Please obtain a copy of the License at
+ * http://www.apple.com/publicsource and read it before using this file.
+ *
+ * This Original Code and all software distributed under the License are
+ * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
+ * License for the specific language governing rights and limitations
+ * under the License.
+ *
+ * @APPLE_LICENSE_HEADER_END@
+ */
+
+#include <sys/errno.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/wait.h>
+
+#include <err.h>
+#include <fcntl.h>
+#include <fstab.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <paths.h>
+#include <unistd.h>
+#include <signal.h>
+
+char *warning = "\
+#\n\
+# Warning - this file should only be modified with vifs(8)\n\
+#\n\
+# Failure to do so is unsupported and may be destructive.\n\
+#\n";
+
+int
+main(int argc, char *argv[])
+{
+	struct stat sb;
+	int fd, x;
+	uid_t euid;
+	pid_t editpid;
+	char *p, *editor;
+
+	if (argc != 1) {
+		printf("usage: vifs\n");
+		exit(1);
+	}
+
+	euid = geteuid();
+	if (euid != 0)
+		errx(1, "need to run as root");
+
+	/* examine the existing fstab, try to create it if needed */
+	if (stat(_PATH_FSTAB, &sb) < 0) {
+		if (errno == ENOENT) {
+			fd = open(_PATH_FSTAB, O_CREAT | O_WRONLY,
+			     S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
+			if (fd < 0)
+				errx(1, "error creating %s", _PATH_FSTAB);
+			write(fd, warning, strlen(warning));
+			close(fd);
+		} else {
+			errx(1, "could not stat %s", _PATH_FSTAB);
+		}
+	}
+
+	/* prepare the file for the editor */
+	fd = open(_PATH_FSTAB, O_RDONLY, 0);
+	if (fd < 0)
+		errx(1, "error opening %s", _PATH_FSTAB);
+
+	x = fcntl(fd, F_SETFD, 1);
+	if (x < 0)
+		errx(1, "error setting close on exit");
+
+	x = flock(fd, LOCK_EX | LOCK_NB);
+	if (x != 0)
+		errx(1, "file is busy");
+
+	/* obtain and invoke the editor */
+	editor = getenv("EDITOR");
+	if (editor == NULL)
+		editor = _PATH_VI;
+	p = strrchr(editor, '/');
+        if (p != NULL)
+		++p;
+	else
+		p = editor;
+
+	editpid = vfork();
+	if (editpid == 0) {
+		execlp(editor, p, _PATH_FSTAB, NULL);
+		_exit(1);
+	}
+
+	for ( ; ; ) {
+		editpid = waitpid(editpid, (int *)&x, WUNTRACED);
+		if (editpid == -1)
+			errx(1, "editing error");
+		else if (WIFSTOPPED(x))
+			raise(WSTOPSIG(x));
+		else if (WIFEXITED(x) && WEXITSTATUS(x) == 0)
+			break;
+                else
+			errx(1, "editing error");
+	}
+
+	/* let process death clean up locks and file descriptors */
+	return 0;
+}