Ensure we aren't duplicatively reading things in router_target

diff --git a/fuzz/fuzz_targets/router_target.rs b/fuzz/fuzz_targets/router_target.rs
index f88ea9e6a2982cdc613f2431a51b195c77262a72..288dc56a432cee896a646d16017fdd423745af41 100644 (file)
--- a/fuzz/fuzz_targets/router_target.rs
+++ b/fuzz/fuzz_targets/router_target.rs
@@ -63,6 +63,13 @@ impl InputData {
                }
                Some(&self.data[old_pos..old_pos + len])
        }
+       fn get_slice_nonadvancing(&self, len: usize) -> Option<&[u8]> {
+               let old_pos = self.read_pos.load(Ordering::Acquire);
+               if self.data.len() < old_pos + len {
+                       return None;
+               }
+               Some(&self.data[old_pos..old_pos + len])
+       }
 }
 
 struct DummyChainWatcher {
@@ -94,23 +101,23 @@ impl ChainWatchInterface for DummyChainWatcher {
 pub fn do_test(data: &[u8]) {
        reset_rng_state();
 
-       let mut read_pos = 0;
+       let input = Arc::new(InputData {
+               data: data.to_vec(),
+               read_pos: AtomicUsize::new(0),
+       });
        macro_rules! get_slice_nonadvancing {
                ($len: expr) => {
-                       {
-                               if data.len() < read_pos + $len as usize {
-                                       return;
-                               }
-                               &data[read_pos..read_pos + $len as usize]
+                       match input.get_slice_nonadvancing($len as usize) {
+                               Some(slice) => slice,
+                               None => return,
                        }
                }
        }
        macro_rules! get_slice {
                ($len: expr) => {
-                       {
-                               let res = get_slice_nonadvancing!($len);
-                               read_pos += $len;
-                               res
+                       match input.get_slice($len as usize) {
+                               Some(slice) => slice,
+                               None => return,
                        }
                }
        }
@@ -153,12 +160,8 @@ pub fn do_test(data: &[u8]) {
        }
 
        let logger: Arc<Logger> = Arc::new(test_logger::TestLogger{});
-       let input = Arc::new(InputData {
-               data: data.to_vec(),
-               read_pos: AtomicUsize::new(0),
-       });
        let chain_monitor = Arc::new(DummyChainWatcher {
-               input: input,
+               input: Arc::clone(&input),
        });
 
        let our_pubkey = get_pubkey!();