Add cargo-fuzz related files.

Author: frewsxcv

Cargo.toml

@@ -8,6 +8,7 @@ keywords = ["parser", "WebAssembly", "wasm"]
 description = """
 A simple event-driven library for parsing WebAssembly binary files.
 """
+exclude = ["fuzz/"]
 
 [dependencies]
 

README.md

@@ -36,3 +36,21 @@ fn main() {
   }
 }
 ```
+
+## Fuzzing
+
+To fuzz test wasmparser.rs, switch to a nightly Rust compiler and install [cargo-fuzz]:
+
+```
+cargo install cargo-fuzz
+```
+
+Then, from the root of the repository, run:
+
+```
+cargo fuzz run parse
+```
+
+If you want to use files as seeds for the fuzzer, add them to `fuzz/corpus/parse/` and restart cargo-fuzz.
+
+[cargo-fuzz]: https://github.com/rust-fuzz/cargo-fuzz

fuzz/.gitignore

@@ -0,0 +1,3 @@
+target
+corpus
+artifacts

fuzz/Cargo.toml

@@ -0,0 +1,22 @@
+[package]
+name = "wasmparser-fuzz"
+version = "0.0.1"
+authors = ["Yury Delendik <[email protected]>"]
+publish = false
+
+[package.metadata]
+cargo-fuzz = true
+
+[dependencies.wasmparser]
+path = ".."
+
+[dependencies.libfuzzer-sys]
+git = "https://github.com/rust-fuzz/libfuzzer-sys.git"
+
+# Prevent this from interfering with workspaces
+[workspace]
+members = ["."]
+
+[[bin]]
+name = "parse"
+path = "fuzz_targets/parse.rs"

fuzz/fuzz_targets/parse.rs

@@ -0,0 +1,16 @@
+#![no_main]
+
+#[macro_use]
+extern crate libfuzzer_sys;
+extern crate wasmparser;
+
+fuzz_target!(|data: &[u8]| {
+    let mut parser = wasmparser::Parser::new(data);
+    loop {
+        match *parser.read() {
+            wasmparser::ParserState::Error(..) |
+            wasmparser::ParserState::EndWasm => break,
+            _ => (),
+        }
+    }
+});