1 files changed, 150 insertions, 0 deletions
diff --git a/lib/e2p/mntopts.c b/lib/e2p/mntopts.c
new file mode 100644
index 0000000..7d0ae9c
--- /dev/null
+++ b/lib/e2p/mntopts.c
@@ -0,0 +1,150 @@
+/*
+ * mountopts.c --- convert between default mount options and strings
+ *
+ * Copyright (C) 2002  Theodore Ts'o <tytso@mit.edu>
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the GNU Library
+ * General Public License, version 2.
+ * %End-Header%
+ */
+
+#include "config.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include <ctype.h>
+#include <errno.h>
+
+#include "e2p.h"
+
+struct mntopt {
+	unsigned int	mask;
+	const char	*string;
+};
+
+static struct mntopt mntopt_list[] = {
+	{ EXT2_DEFM_DEBUG,	"debug" },
+	{ EXT2_DEFM_BSDGROUPS,	"bsdgroups" },
+	{ EXT2_DEFM_XATTR_USER,	"user_xattr" },
+	{ EXT2_DEFM_ACL,	"acl" },
+	{ EXT2_DEFM_UID16,	"uid16" },
+	{ EXT3_DEFM_JMODE_DATA, "journal_data" },
+	{ EXT3_DEFM_JMODE_ORDERED, "journal_data_ordered" },
+	{ EXT3_DEFM_JMODE_WBACK, "journal_data_writeback" },
+	{ EXT4_DEFM_NOBARRIER,	"nobarrier" },
+	{ EXT4_DEFM_BLOCK_VALIDITY, "block_validity" },
+	{ EXT4_DEFM_DISCARD,	"discard"},
+	{ EXT4_DEFM_NODELALLOC,	"nodelalloc"},
+	{ 0, 0 },
+};
+
+const char *e2p_mntopt2string(unsigned int mask)
+{
+	struct mntopt  *f;
+	static char buf[20];
+	int	fnum;
+
+	for (f = mntopt_list; f->string; f++) {
+		if (mask == f->mask)
+			return f->string;
+	}
+	for (fnum = 0; mask >>= 1; fnum++);
+	sprintf(buf, "MNTOPT_%d", fnum);
+	return buf;
+}
+
+int e2p_string2mntopt(char *string, unsigned int *mask)
+{
+	struct mntopt  *f;
+	char		*eptr;
+	int		num;
+
+	for (f = mntopt_list; f->string; f++) {
+		if (!strcasecmp(string, f->string)) {
+			*mask = f->mask;
+			return 0;
+		}
+	}
+	if (strncasecmp(string, "MNTOPT_", 7))
+		return 1;
+
+	if (string[8] == 0)
+		return 1;
+	num = strtol(string+8, &eptr, 10);
+	if (num > 31 || num < 0)
+		return 1;
+	if (*eptr)
+		return 1;
+	*mask = 1 << num;
+	return 0;
+}
+
+static char *skip_over_blanks(char *cp)
+{
+	while (*cp && isspace(*cp))
+		cp++;
+	return cp;
+}
+
+static char *skip_over_word(char *cp)
+{
+	while (*cp && !isspace(*cp) && *cp != ',')
+		cp++;
+	return cp;
+}
+
+/*
+ * Edit a mntopt set array as requested by the user.  The ok
+ * parameter, if non-zero, allows the application to limit what
+ * mntopts the user is allowed to set or clear using this function.
+ */
+int e2p_edit_mntopts(const char *str, __u32 *mntopts, __u32 ok)
+{
+	char	*cp, *buf, *next;
+	int	neg;
+	unsigned int	mask;
+	int	rc = 0;
+
+	buf = malloc(strlen(str)+1);
+	if (!buf)
+		return 1;
+	strcpy(buf, str);
+	cp = buf;
+	while (cp && *cp) {
+		neg = 0;
+		cp = skip_over_blanks(cp);
+		next = skip_over_word(cp);
+		if (*next == 0)
+			next = 0;
+		else
+			*next = 0;
+		switch (*cp) {
+		case '-':
+		case '^':
+			neg++;
+			/* fallthrough */
+		case '+':
+			cp++;
+			break;
+		}
+		if (e2p_string2mntopt(cp, &mask)) {
+			rc = 1;
+			break;
+		}
+		if (ok && !(ok & mask)) {
+			rc = 1;
+			break;
+		}
+		if (mask & EXT3_DEFM_JMODE)
+			*mntopts &= ~EXT3_DEFM_JMODE;
+		if (neg)
+			*mntopts &= ~mask;
+		else
+			*mntopts |= mask;
+		cp = next ? next+1 : 0;
+	}
+	free(buf);
+	return rc;
+}