Revert back to using custom HTTP parser instead of Boost.Beast (#6407)

fuzz/CMakeLists.txt

@@ -38,7 +38,8 @@ if (ENABLE_FUZZING)
 	  "table_parameters"
 	  "tile_parameters"
 	  "trip_parameters"
-	  "url_parser")
+	  "url_parser"
+	  "request_parser")
 
   foreach (target ${ServerTargets})
 	  add_fuzz_target(${target})

fuzz/request_parser.cc

@@ -0,0 +1,28 @@
+#include "server/request_parser.hpp"
+#include "server/http/request.hpp"
+
+#include "util.hpp"
+
+#include <iterator>
+#include <string>
+
+using osrm::server::RequestParser;
+using osrm::server::http::request;
+
+extern "C" int LLVMFuzzerTestOneInput(const unsigned char *data, unsigned long size)
+{
+    std::string in(reinterpret_cast<const char *>(data), size);
+
+    auto first = begin(in);
+    auto last = end(in);
+
+    RequestParser parser;
+    request req;
+
+    // &(*it) is needed to go from iterator to underlying item to pointer to underlying item
+    parser.parse(req, &(*first), &(*last));
+
+    escape(&req);
+
+    return 0;
+}