xref: /wasmtime-44.0.1/crates/fuzzing/src/lib.rs (revision 57618f74)
1 //! Fuzzing infrastructure for Wasmtime.
2 
3 #![deny(missing_docs)]
4 
5 pub use wasm_smith;
6 pub mod generators;
7 pub mod oracles;
8 
9 /// One time start up initialization for fuzzing:
10 ///
11 /// * Enables `env_logger`.
12 ///
13 /// * Restricts `rayon` to a single thread in its thread pool, for more
14 ///   deterministic executions.
15 ///
16 /// If a fuzz target is taking raw input bytes from the fuzzer, it is fine to
17 /// call this function in the fuzz target's oracle or in the fuzz target
18 /// itself. However, if the fuzz target takes an `Arbitrary` type, and the
19 /// `Arbitrary` implementation is not derived and does interesting things, then
20 /// the `Arbitrary` implementation should call this function, since it runs
21 /// before the fuzz target itself.
22 pub(crate) fn init_fuzzing() {
23     static INIT: std::sync::Once = std::sync::Once::new();
24 
25     INIT.call_once(|| {
26         let _ = env_logger::try_init();
27 
28         let _ = rayon::ThreadPoolBuilder::new()
29             .num_threads(1)
30             .build_global();
31     })
32 }
33