1 files changed, 38 insertions, 0 deletions
diff --git a/vendor/gix-index/src/extension/fs_monitor.rs b/vendor/gix-index/src/extension/fs_monitor.rs
new file mode 100644
index 000000000..4bb5016ff
--- /dev/null
+++ b/vendor/gix-index/src/extension/fs_monitor.rs
@@ -0,0 +1,38 @@
+use bstr::BString;
+
+use crate::{
+    extension::{FsMonitor, Signature},
+    util::{read_u32, read_u64, split_at_byte_exclusive},
+};
+
+#[derive(Clone)]
+pub enum Token {
+    V1 { nanos_since_1970: u64 },
+    V2 { token: BString },
+}
+
+pub const SIGNATURE: Signature = *b"FSMN";
+
+pub fn decode(data: &[u8]) -> Option<FsMonitor> {
+    let (version, data) = read_u32(data)?;
+    let (token, data) = match version {
+        1 => {
+            let (nanos_since_1970, data) = read_u64(data)?;
+            (Token::V1 { nanos_since_1970 }, data)
+        }
+        2 => {
+            let (token, data) = split_at_byte_exclusive(data, 0)?;
+            (Token::V2 { token: token.into() }, data)
+        }
+        _ => return None,
+    };
+
+    let (ewah_size, data) = read_u32(data)?;
+    let (entry_dirty, data) = gix_bitmap::ewah::decode(&data[..ewah_size as usize]).ok()?;
+
+    if !data.is_empty() {
+        return None;
+    }
+
+    FsMonitor { token, entry_dirty }.into()
+}