diff options
Diffstat (limited to 'louloulibs/network/resolver.hpp')
-rw-r--r-- | louloulibs/network/resolver.hpp | 128 |
1 files changed, 128 insertions, 0 deletions
diff --git a/louloulibs/network/resolver.hpp b/louloulibs/network/resolver.hpp new file mode 100644 index 0000000..afe6e2b --- /dev/null +++ b/louloulibs/network/resolver.hpp @@ -0,0 +1,128 @@ +#pragma once + + +#include "louloulibs.h" + +#include <functional> +#include <memory> +#include <string> + +#include <sys/types.h> +#include <sys/socket.h> +#include <netdb.h> + +struct AddrinfoDeleter +{ + void operator()(struct addrinfo* addr) + { +#ifdef CARES_FOUND + while (addr) + { + delete addr->ai_addr; + auto next = addr->ai_next; + delete addr; + addr = next; + } +#else + freeaddrinfo(addr); +#endif + } +}; + +class Resolver +{ +public: + using ErrorCallbackType = std::function<void(const char*)>; + using SuccessCallbackType = std::function<void(const struct addrinfo*)>; + + Resolver(); + ~Resolver() = default; + Resolver(const Resolver&) = delete; + Resolver(Resolver&&) = delete; + Resolver& operator=(const Resolver&) = delete; + Resolver& operator=(Resolver&&) = delete; + + bool is_resolving() const + { +#ifdef CARES_FOUND + return this->resolving; +#else + return false; +#endif + } + + bool is_resolved() const + { + return this->resolved; + } + + const auto& get_result() const + { + return this->addr; + } + std::string get_error_message() const + { + return this->error_msg; + } + + void clear() + { +#ifdef CARES_FOUND + this->resolved6 = false; + this->resolved4 = false; + this->resolving = false; + this->cares_addrinfo = nullptr; + this->port.clear(); +#endif + this->resolved = false; + this->addr.reset(); + this->error_msg.clear(); + } + + void resolve(const std::string& hostname, const std::string& port, + SuccessCallbackType success_cb, ErrorCallbackType error_cb); + +private: + void start_resolving(const std::string& hostname, const std::string& port); +#ifdef CARES_FOUND + void on_hostname4_resolved(int status, struct hostent* hostent); + void on_hostname6_resolved(int status, struct hostent* hostent); + + void fill_ares_addrinfo4(const struct hostent* hostent); + void fill_ares_addrinfo6(const struct hostent* hostent); + + void on_resolved(); + + bool resolved4; + bool resolved6; + + bool resolving; + + /** + * When using c-ares to resolve the host asynchronously, we need the + * c-ares callbacks to fill a structure (a struct addrinfo, for + * compatibility with getaddrinfo and the rest of the code that works when + * c-ares is not used) with all returned values (for example an IPv6 and + * an IPv4). The pointer is given to the unique_ptr to manage its lifetime. + */ + struct addrinfo* cares_addrinfo; + std::string port; + +#endif + /** + * Tells if we finished the resolution process. It doesn't indicate if it + * was successful (it is true even if the result is an error). + */ + bool resolved; + std::string error_msg; + + + std::unique_ptr<struct addrinfo, AddrinfoDeleter> addr; + + ErrorCallbackType error_cb; + SuccessCallbackType success_cb; +}; + +std::string addr_to_string(const struct addrinfo* rp); + + |