Class Trap

crates/c-api/include/wasmtime/trap.hh:113–150

* \brief Information about a WebAssembly trap. * * Traps can happen during normal wasm execution (such as the `unreachable` * instruction) but they can also happen in host-provided functions to a host * function can simulate raising a trap. * * Traps have a message associated with them as well as a trace of WebAssembly * frames on the stack. */

 * frames on the stack.
 */
class Trap {
  WASMTIME_OWN_WRAPPER(Trap, wasm_trap);

  /// Creates a new host-defined trap with the specified message.
  explicit Trap(std::string_view msg)
      : Trap(wasmtime_trap_new(msg.data(), msg.size())) {}

  /// Creates a new trap with the given wasmtime trap code.
  Trap(wasmtime_trap_code_enum code) : Trap(wasmtime_trap_new_code(code)) {}

  /// Returns the descriptive message associated with this trap.
  std::string message() const {
    wasm_byte_vec_t msg;
    wasm_trap_message(ptr.get(), &msg);
    std::string ret(msg.data, msg.size - 1);
    wasm_byte_vec_delete(&msg);
    return ret;
  }

  /// Returns the trace of WebAssembly frames associated with this trap.
  ///
  /// Note that the `trace` cannot outlive this error object.
  Trace trace() const {
    wasm_frame_vec_t frames;
    wasm_trap_trace(ptr.get(), &frames);
    return Trace(frames);
  }

  /// \brief Returns the trap code associated with this trap, or nothing if
  /// it was a manually created trap.
  std::optional<wasmtime_trap_code_t> code() const {
    wasmtime_trap_code_t code;
    bool present = wasmtime_trap_code(ptr.get(), &code);
    if (present)
      return code;
    return std::nullopt;
  }
};

/// Structure used to represent either a `Trap` or an `Error`.
struct TrapError {