Initial reorg.

This is largely the same as #305, but updated for the current tree.

crates/lightbeam/src/error.rs

@@ -0,0 +1,28 @@
+use capstone;
+use thiserror::Error;
+use wasmparser::BinaryReaderError;
+
+#[derive(Error, PartialEq, Eq, Clone, Debug)]
+pub enum Error {
+    #[error("Disassembler error: {0}")]
+    Disassembler(String),
+
+    #[error("Assembler error: {0}")]
+    Assembler(String),
+
+    #[error("Input error: {0}")]
+    Input(String),
+}
+
+impl From<BinaryReaderError> for Error {
+    fn from(e: BinaryReaderError) -> Self {
+        let BinaryReaderError { message, offset } = e;
+        Error::Input(format!("At wasm offset {}: {}", offset, message))
+    }
+}
+
+impl From<capstone::Error> for Error {
+    fn from(e: capstone::Error) -> Self {
+        Error::Disassembler(e.to_string())
+    }
+}