From 5f0c1d0f8d3e623e368da8fea42da9e5f69b85a0 Mon Sep 17 00:00:00 2001
From: Adrian Taylor <adetaylor@chromium.org>
Date: Fri, 4 Mar 2022 13:19:14 -0800
Subject: [PATCH] Add a fuzzer.

---
 fuzz/Cargo.toml                | 24 +++++++++++++++++++
 fuzz/fuzz_targets/fuzz_itoa.rs | 44 ++++++++++++++++++++++++++++++++++
 2 files changed, 68 insertions(+)
 create mode 100644 fuzz/Cargo.toml
 create mode 100644 fuzz/fuzz_targets/fuzz_itoa.rs

diff --git a/fuzz/Cargo.toml b/fuzz/Cargo.toml
new file mode 100644
index 0000000..e815cd2
--- /dev/null
+++ b/fuzz/Cargo.toml
@@ -0,0 +1,24 @@
+[package]
+name = "itoa-fuzz"
+version = "0.0.0"
+publish = false
+edition = "2018"
+
+[package.metadata]
+cargo-fuzz = true
+
+[dependencies]
+libfuzzer-sys = { version="0.4", features=["arbitrary-derive"] }
+
+[dependencies.itoa]
+path = ".."
+
+# Prevent this from interfering with workspaces
+[workspace]
+members = ["."]
+
+[[bin]]
+name = "fuzz_itoa"
+path = "fuzz_targets/fuzz_itoa.rs"
+test = false
+doc = false
diff --git a/fuzz/fuzz_targets/fuzz_itoa.rs b/fuzz/fuzz_targets/fuzz_itoa.rs
new file mode 100644
index 0000000..e080126
--- /dev/null
+++ b/fuzz/fuzz_targets/fuzz_itoa.rs
@@ -0,0 +1,44 @@
+#![no_main]
+use libfuzzer_sys::arbitrary;
+use libfuzzer_sys::fuzz_target;
+
+#[derive(arbitrary::Arbitrary, Debug, Clone)]
+enum IntegerInput {
+    I8(i8),
+    U8(u8),
+    I16(i16),
+    U16(u16),
+    I32(i32),
+    U32(u32),
+    I64(i64),
+    U64(u64),
+    ISIZE(isize),
+    USIZE(usize),
+    I128(i128),
+    U128(u128),
+}
+
+#[derive(arbitrary::Arbitrary, Debug, Clone)]
+struct Inputs {
+    inputs: Vec<IntegerInput>,
+}
+
+fuzz_target!(|input: Inputs| {
+    let mut buffer = itoa::Buffer::new();
+    for input_integer in input.inputs {
+        match input_integer {
+            IntegerInput::I8(val) => buffer.format(val),
+            IntegerInput::U8(val) => buffer.format(val),
+            IntegerInput::I16(val) => buffer.format(val),
+            IntegerInput::U16(val) => buffer.format(val),
+            IntegerInput::I32(val) => buffer.format(val),
+            IntegerInput::U32(val) => buffer.format(val),
+            IntegerInput::I64(val) => buffer.format(val),
+            IntegerInput::U64(val) => buffer.format(val),
+            IntegerInput::ISIZE(val) => buffer.format(val),
+            IntegerInput::USIZE(val) => buffer.format(val),
+            IntegerInput::I128(val) => buffer.format(val),
+            IntegerInput::U128(val) => buffer.format(val),
+        };
+    }
+});