init

src/util.rs

@@ -0,0 +1,37 @@
+use std::fmt::Write as _;
+
+use crate::errors::VmError;
+
+pub(crate) fn bytes_to_hex(bytes: &[u8]) -> String {
+    let mut out = String::with_capacity(bytes.len() * 2);
+    for byte in bytes {
+        let _ = write!(out, "{byte:02x}");
+    }
+    out
+}
+
+pub(crate) fn align_up(value: u64, align: u64) -> u64 {
+    if align == 0 {
+        return value;
+    }
+    (value + align - 1) & !(align - 1)
+}
+
+pub(crate) fn align_down(value: u64, align: u64) -> u64 {
+    if align == 0 {
+        return value;
+    }
+    value & !(align - 1)
+}
+
+pub(crate) fn add_i64(base: u64, addend: i64) -> u64 {
+    if addend >= 0 {
+        base.wrapping_add(addend as u64)
+    } else {
+        base.wrapping_sub((-addend) as u64)
+    }
+}
+
+pub(crate) fn as_usize(value: u64) -> Result<usize, VmError> {
+    usize::try_from(value).map_err(|_| VmError::IntegerOverflow(value))
+}