rust binding for parse_mount_opts()

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

bch_bindgen/src/opts.rs

@@ -1,3 +1,7 @@
+use crate::c;
+use crate::fs::Fs;
+use std::ffi::{CString, c_char};
+
 #[macro_export]
 macro_rules! opt_set {
     ($opts:ident, $n:ident, $v:expr) => {
@@ -33,3 +37,29 @@ macro_rules! opt_get {
         }
     };
 }
+
+pub fn parse_mount_opts(fs: Option<&mut Fs>, optstr: Option<&str>, ignore_unknown: bool)
+        -> Result<c::bch_opts, c::bch_errcode> {
+    let mut opts: c::bch_opts = Default::default();
+
+    if let Some(optstr) = optstr {
+        let optstr = CString::new(optstr).unwrap();
+        let optstr_ptr = optstr.as_ptr();
+
+        let ret = unsafe {
+            c::bch2_parse_mount_opts(fs.map_or(std::ptr::null_mut(), |f| f.raw),
+                                     &mut opts as *mut c::bch_opts,
+                                     std::ptr::null_mut(),
+                                     optstr_ptr as *mut c_char,
+                                     ignore_unknown)
+        };
+
+        drop(optstr);
+
+        if ret != 0 {
+            let err: c::bch_errcode = unsafe { std::mem::transmute(-ret) };
+            return Err(err);
+        }
+    }
+    Ok(opts)
+}