Improve fuzz test coverage

Add fuzz target and corpus for testing ip_representation() API

Author: sgbhat2

test/fuzz/README.md

@@ -25,10 +25,14 @@ make && sudo make install
 ```
 cd libhttpserver/test/fuzz
 clang++ $CXXFLAGS basic_fuzzer.cc -o basic_fuzzer -fsanitize=fuzzer,undefined /usr/local/lib/libhttpserver.a /usr/local/lib/libmicrohttpd.a -lgnutls
+clang++ $CXXFLAGS ip_representation.cc -o ip_representation -fsanitize=fuzzer,undefined /usr/local/lib/libhttpserver.a /usr/local/lib/libmicrohttpd.a -lgnutls
 ```
 
 ## Run the fuzz target
 ```
 unzip basic_fuzzer_seed_corpus.zip
 ./basic_fuzzer corpus/
+
+unzip ip_representation_seed_corpus.zip
+./ip_representation ip_corpus/
 ```

test/fuzz/basic_fuzzer.cc

@@ -31,6 +31,16 @@ class fuzz_resource : public http_resource {
 public:
     const std::shared_ptr<http_response> render(const http_request& req) {
         std::stringstream ss;
+        req.get_args();
+        req.get_headers();
+        req.get_footers();
+        req.get_cookies();
+        req.get_querystring();
+        req.get_user();
+        req.get_pass();
+        req.get_digested_user();
+        req.get_requestor();
+        req.get_requestor_port();
         for (unsigned int i = 0; i < req.get_path_pieces().size(); i++)
             ss << req.get_path_piece(i) << ",";
         return std::shared_ptr<http_response>(new string_response(ss.str(), 200));

test/fuzz/ip_representation.cc

@@ -0,0 +1,14 @@
+#include <httpserver.hpp>
+
+using namespace httpserver;
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
+	if (!size)
+		return 0;
+	std::string str(reinterpret_cast<const char *>(data), size);
+	try {
+		http::ip_representation test(str);
+	} catch (std::exception &e) {
+		return 0;
+	}
+	return 0;
+}