1 files changed, 40 insertions, 0 deletions
diff --git a/users/fogti/store-ref-scanner/src/spec.rs b/users/fogti/store-ref-scanner/src/spec.rs
new file mode 100644
index 000000000000..79da0842c529
--- /dev/null
+++ b/users/fogti/store-ref-scanner/src/spec.rs
@@ -0,0 +1,40 @@
+use crate::hbm::HalfBytesMask;
+
+pub struct StoreSpec<'path> {
+    /// path to store without trailing slash
+    pub path_to_store: &'path str,
+
+    /// compressed map of allowed ASCII characters in hash part
+    pub valid_hashbytes: HalfBytesMask,
+
+    /// compressed map of allowed ASCII characters in part after hash
+    pub valid_restbytes: HalfBytesMask,
+
+    /// exact length of hash part of store paths
+    pub hashbytes_len: u8,
+}
+
+impl StoreSpec<'_> {
+    pub(crate) fn check_rest(&self, rest: &[u8]) -> bool {
+        let hbl = self.hashbytes_len.into();
+        rest.iter()
+            .take(hbl)
+            .take_while(|&&i| self.valid_hashbytes.contains(i))
+            .count()
+            == hbl
+    }
+
+    pub const DFL_NIX2: StoreSpec<'static> = StoreSpec {
+        path_to_store: "/nix/store",
+        valid_hashbytes: HalfBytesMask::B32_REVSHA256,
+        valid_restbytes: HalfBytesMask::DFL_REST,
+        hashbytes_len: 32,
+    };
+
+    pub const DFL_YZIX1: StoreSpec<'static> = StoreSpec {
+        path_to_store: "/yzixs",
+        valid_hashbytes: HalfBytesMask::B64_BLAKE2B256,
+        valid_restbytes: HalfBytesMask::DFL_REST,
+        hashbytes_len: 43,
+    };
+}