Parse TCP host using hostname:port format

Source/dvlnet/abstract_net.h

@@ -16,8 +16,8 @@ using provider_t = unsigned long;
 
 class abstract_net {
 public:
-	virtual int create(std::string addrstr) = 0;
-	virtual int join(std::string addrstr) = 0;
+	virtual int create(std::string_view addrstr) = 0;
+	virtual int join(std::string_view addrstr) = 0;
 	virtual bool SNetReceiveMessage(uint8_t *sender, void **data, size_t *size) = 0;
 	virtual bool SNetSendMessage(uint8_t dest, void *data, size_t size) = 0;
 	virtual bool SNetReceiveTurns(char **data, size_t *size, uint32_t *status) = 0;

Source/dvlnet/base_protocol.h

@@ -15,8 +15,8 @@ namespace devilution::net {
 template <class P>
 class base_protocol : public base {
 public:
-	int create(std::string addrstr) override;
-	int join(std::string addrstr) override;
+	int create(std::string_view addrstr) override;
+	int join(std::string_view addrstr) override;
 	tl::expected<void, PacketError> poll() override;
 	tl::expected<void, PacketError> send(packet &pkt) override;
 	void DisconnectNet(plr_t plr) override;
@@ -161,7 +161,7 @@ tl::expected<void, PacketError> base_protocol<P>::wait_join()
 }
 
 template <class P>
-int base_protocol<P>::create(std::string addrstr)
+int base_protocol<P>::create(std::string_view addrstr)
 {
 	gamename = addrstr;
 	isGameHost_ = true;
@@ -183,7 +183,7 @@ int base_protocol<P>::create(std::string addrstr)
 }
 
 template <class P>
-int base_protocol<P>::join(std::string addrstr)
+int base_protocol<P>::join(std::string_view addrstr)
 {
 	gamename = addrstr;
 	isGameHost_ = false;

Source/dvlnet/cdwrap.cpp

@@ -17,13 +17,13 @@ void cdwrap::reset()
 		dvlnet_wrap->SNetRegisterEventHandler(eventType, eventHandler);
 }
 
-int cdwrap::create(std::string addrstr)
+int cdwrap::create(std::string_view addrstr)
 {
 	reset();
 	return dvlnet_wrap->create(addrstr);
 }
 
-int cdwrap::join(std::string addrstr)
+int cdwrap::join(std::string_view addrstr)
 {
 	game_init_info = buffer_t();
 	reset();

Source/dvlnet/cdwrap.h

@@ -32,8 +32,8 @@ class cdwrap : public abstract_net {
 		reset();
 	}
 
-	int create(std::string addrstr) override;
-	int join(std::string addrstr) override;
+	int create(std::string_view addrstr) override;
+	int join(std::string_view addrstr) override;
 	bool SNetReceiveMessage(uint8_t *sender, void **data, size_t *size) override;
 	bool SNetSendMessage(uint8_t dest, void *data, size_t size) override;
 	bool SNetReceiveTurns(char **data, size_t *size, uint32_t *status) override;

Source/dvlnet/loopback.cpp

@@ -9,13 +9,13 @@
 
 namespace devilution::net {
 
-int loopback::create(std::string /*addrstr*/)
+int loopback::create(std::string_view /*addrstr*/)
 {
 	IsLoopback = true;
 	return plr_single;
 }
 
-int loopback::join(std::string /*addrstr*/)
+int loopback::join(std::string_view /*addrstr*/)
 {
 	ABORT();
 }

Source/dvlnet/loopback.h

@@ -17,8 +17,8 @@ class loopback : public abstract_net {
 public:
 	loopback() = default;
 
-	int create(std::string addrstr) override;
-	int join(std::string addrstr) override;
+	int create(std::string_view addrstr) override;
+	int join(std::string_view addrstr) override;
 	bool SNetReceiveMessage(uint8_t *sender, void **data, size_t *size) override;
 	bool SNetSendMessage(uint8_t dest, void *data, size_t size) override;
 	bool SNetReceiveTurns(char **data, size_t *size, uint32_t *status) override;

Source/dvlnet/tcp_client.cpp

@@ -13,25 +13,56 @@
 #include "options.h"
 #include "utils/language.h"
 #include "utils/str_cat.hpp"
+#include "utils/str_split.hpp"
 
 namespace devilution::net {
 
-int tcp_client::create(std::string addrstr)
+int tcp_client::create(std::string_view addrstr)
 {
 	auto port = *sgOptions.Network.port;
-	local_server = std::make_unique<tcp_server>(ioc, addrstr, port, *pktfty);
+	local_server = std::make_unique<tcp_server>(ioc, std::string(addrstr), port, *pktfty);
 	return join(local_server->LocalhostSelf());
 }
 
-int tcp_client::join(std::string addrstr)
+int tcp_client::join(std::string_view addrstr)
 {
 	constexpr int MsSleep = 10;
 	constexpr int NoSleep = 250;
 
-	std::string port = StrCat(*sgOptions.Network.port);
+	const char *defaultPort = "6112";
+	std::string_view host;
+	std::string_view port = defaultPort;
+	if (!addrstr.empty() && addrstr[0] == '[') {
+		// Assume IPv6 address in square brackets, followed by port
+		// Example: [::1]:6113
+		size_t pos = addrstr.find(']', 1);
+		pos = pos != std::string::npos ? pos + 1 : addrstr.length();
+		host = addrstr.substr(0, pos);
+
+		if (pos != addrstr.length()) {
+			if (addrstr[pos] != ':') {
+				SDL_SetError("Invalid hostname: expected colon after square brackets");
+				return -1;
+			}
+			if (++pos != addrstr.length())
+				port = addrstr.substr(pos);
+		}
+	} else {
+		// Assume "hostname:port"
+		SplitByChar splithost(addrstr, ':');
+		auto it = splithost.begin();
+		if (it != splithost.end()) host = *it++;
+		if (it != splithost.end()) port = *it++;
+
+		// If there is more than one colon, assume it's just a plain IPv6 address
+		if (it != splithost.end()) {
+			host = addrstr;
+			port = defaultPort;
+		}
+	}
 
 	asio::error_code errorCode;
-	asio::ip::basic_resolver_results<asio::ip::tcp> range = resolver.resolve(addrstr, port, errorCode);
+	asio::ip::basic_resolver_results<asio::ip::tcp> range = resolver.resolve(host, port, errorCode);
 	if (errorCode) {
 		SDL_SetError("%s", errorCode.message().c_str());
 		return -1;

Source/dvlnet/tcp_client.h

@@ -27,8 +27,8 @@ namespace devilution::net {
 
 class tcp_client : public base {
 public:
-	int create(std::string addrstr) override;
-	int join(std::string addrstr) override;
+	int create(std::string_view addrstr) override;
+	int join(std::string_view addrstr) override;
 
 	tl::expected<void, PacketError> poll() override;
 	tl::expected<void, PacketError> send(packet &pkt) override;