use libblkid to get filesystem type
we can now use libblkid to detect exfat
diff --git a/libblkid/xgetpass.c b/libblkid/xgetpass.c
new file mode 100644
index 0000000..ba20894
--- /dev/null
+++ b/libblkid/xgetpass.c
@@ -0,0 +1,46 @@
+/*
+ * A function to read the passphrase either from the terminal or from
+ * an open file descriptor.
+ *
+ * Public domain.
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+
+#include "c.h"
+#include "xgetpass.h"
+
+char *xgetpass(int pfd, const char *prompt)
+{
+ char *pass = NULL;
+ int len = 0, i;
+
+ if (pfd < 0) /* terminal */
+ return getpass(prompt);
+
+ for (i=0; ; i++) {
+ if (i >= len-1) {
+ char *tmppass = pass;
+ len += 128;
+
+ pass = realloc(tmppass, len);
+ if (!pass) {
+ pass = tmppass; /* the old buffer hasn't changed */
+ break;
+ }
+ }
+ if (pass && (read(pfd, pass + i, 1) != 1 ||
+ pass[i] == '\n' || pass[i] == 0))
+ break;
+ }
+
+ if (pass)
+ pass[i] = '\0';
+ return pass;
+}
+