1 files changed, 43 insertions, 0 deletions
diff --git a/src/const_int.rs b/src/const_int.rs
new file mode 100644
index 0000000..75beeaa
--- /dev/null
+++ b/src/const_int.rs
@@ -0,0 +1,43 @@
+use crate::{Tag, Tagged};
+
+#[derive(Debug)]
+pub struct ConstInt {
+    buffer: [u8; 10],
+    n: usize,
+}
+
+// XXX only ToBer/ToDer trait supported?
+
+impl Tagged for ConstInt {
+    const TAG: Tag = Tag::Integer;
+}
+
+#[derive(Debug)]
+pub struct IntBuilder {}
+
+impl IntBuilder {
+    pub const fn build(&self, i: u64) -> ConstInt {
+        let b = i.to_be_bytes();
+        let mut out = [0u8; 10];
+        out[0] = 0x4;
+        let src_len = b.len();
+        let mut src_index = 0;
+        while src_index < src_len && b[src_index] == 0 {
+            src_index += 1;
+        }
+        out[1] = (src_len - src_index) as u8;
+        let mut dst_index = 2;
+        while src_index < src_len {
+            out[dst_index] = b[src_index];
+            src_index += 1;
+            dst_index += 1;
+        }
+        // XXX will not work: we need to allocate a Vec
+        // also, we cannot just store the bytes (there are extra zeroes at end)
+        // Integer::new(&out[..dst_index])
+        ConstInt {
+            buffer: out,
+            n: dst_index,
+        }
+    }
+}