tests: Add fuzzing harnesses for various number parsing functions

src/test/fuzz/parse_numbers.cpp

@@ -0,0 +1,35 @@
+// Copyright (c) 2009-2019 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include <test/fuzz/fuzz.h>
+#include <util/moneystr.h>
+#include <util/strencodings.h>
+
+#include <string>
+
+void test_one_input(const std::vector<uint8_t>& buffer)
+{
+    const std::string random_string(buffer.begin(), buffer.end());
+
+    CAmount amount;
+    (void)ParseMoney(random_string, amount);
+
+    double d;
+    (void)ParseDouble(random_string, &d);
+
+    int32_t i32;
+    (void)ParseInt32(random_string, &i32);
+    (void)atoi(random_string);
+
+    uint32_t u32;
+    (void)ParseUInt32(random_string, &u32);
+
+    int64_t i64;
+    (void)atoi64(random_string);
+    (void)ParseFixedPoint(random_string, 3, &i64);
+    (void)ParseInt64(random_string, &i64);
+
+    uint64_t u64;
+    (void)ParseUInt64(random_string, &u64);
+}