1 files changed, 102 insertions, 0 deletions
diff --git a/usr/utils/mount_opts.c b/usr/utils/mount_opts.c
new file mode 100644
index 0000000..bb26c7d
--- /dev/null
+++ b/usr/utils/mount_opts.c
@@ -0,0 +1,102 @@
+/*
+ * by rmk
+ *
+ * Decode mount options.
+ */
+#include <sys/mount.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "mount_opts.h"
+
+#define ARRAY_SIZE(x)	(sizeof(x) / sizeof(x[0]))
+
+static const struct mount_opts options[] = {
+	/* name         mask            set             noset           */
+	{"async", MS_SYNCHRONOUS, 0, MS_SYNCHRONOUS},
+	{"atime", MS_NOATIME, 0, MS_NOATIME},
+	{"bind", MS_TYPE, MS_BIND, 0,},
+	{"dev", MS_NODEV, 0, MS_NODEV},
+	{"diratime", MS_NODIRATIME, 0, MS_NODIRATIME},
+	{"dirsync", MS_DIRSYNC, MS_DIRSYNC, 0},
+	{"exec", MS_NOEXEC, 0, MS_NOEXEC},
+	{"move", MS_TYPE, MS_MOVE, 0},
+	{"nodev", MS_NODEV, MS_NODEV, 0},
+	{"noexec", MS_NOEXEC, MS_NOEXEC, 0},
+	{"nosuid", MS_NOSUID, MS_NOSUID, 0},
+	{"recurse", MS_REC, MS_REC, 0},
+	{"remount", MS_TYPE, MS_REMOUNT, 0},
+	{"ro", MS_RDONLY, MS_RDONLY, 0},
+	{"rw", MS_RDONLY, 0, MS_RDONLY},
+	{"suid", MS_NOSUID, 0, MS_NOSUID},
+	{"sync", MS_SYNCHRONOUS, MS_SYNCHRONOUS, 0},
+	{"verbose", MS_VERBOSE, MS_VERBOSE, 0},
+};
+
+static void add_extra_option(struct extra_opts *extra, char *s)
+{
+	int len = strlen(s);
+	int newlen = extra->used_size + len;
+
+	if (extra->str)
+		len++;		/* +1 for ',' */
+
+	if (newlen >= extra->alloc_size) {
+		char *new;
+
+		new = realloc(extra->str, newlen + 1);	/* +1 for NUL */
+		if (!new)
+			return;
+
+		extra->str = new;
+		extra->end = extra->str + extra->used_size;
+		extra->alloc_size = newlen;
+	}
+
+	if (extra->used_size) {
+		*extra->end = ',';
+		extra->end++;
+	}
+	strcpy(extra->end, s);
+	extra->used_size += len;
+
+}
+
+unsigned long
+parse_mount_options(char *arg, unsigned long rwflag, struct extra_opts *extra)
+{
+	char *s;
+
+	while ((s = strsep(&arg, ",")) != NULL) {
+		char *opt = s;
+		unsigned int i;
+		int res, no = s[0] == 'n' && s[1] == 'o';
+
+		if (no)
+			s += 2;
+
+		for (i = 0, res = 1; i < ARRAY_SIZE(options); i++) {
+			res = strcmp(s, options[i].str);
+
+			if (res == 0) {
+				rwflag &= ~options[i].rwmask;
+				if (no)
+					rwflag |= options[i].rwnoset;
+				else
+					rwflag |= options[i].rwset;
+			}
+			if (res <= 0)
+				break;
+		}
+
+		if (res != 0 && s[0]) {
+			if (!strcmp(opt, "defaults"))
+				rwflag &= ~(MS_RDONLY|MS_NOSUID|MS_NODEV|
+					    MS_NOEXEC|MS_SYNCHRONOUS);
+			else
+				add_extra_option(extra, opt);
+		}
+	}
+
+	return rwflag;
+}