Added check to release script, to check if DLL exists

It has been replaced by check_server() and check_client().

README.md

@@ -9,7 +9,7 @@ The game has only one runtime dependency: The [raylib](https://www.raylib.com/)
 ## Building
 
 This application uses [Meson](https://mesonbuild.com/) as a build system. To build the application:
-1. Install __meson__ from the link above.
+1. Install meson from the link above.
 2. Set up the build directory.
 	```
 	meson setup build

check_input.cpp

@@ -1,4 +1,5 @@
 #include <iostream>
+#include <cstdint>
 #include "includes/easysock.h"
 #include "includes/connect_code.hpp"
 #include "includes/server.hpp"
@@ -7,19 +8,20 @@
 #include "includes/raygui/raygui.h"
 #include "includes/exception_consts.hpp"
 #include "includes/raygui_helpers.hpp"
+#include "includes/display_text.hpp"
 #include "includes/timer.h"
 
-GameType check_server(char* ip_text, char* port_text) {
+GameType check_server(char* ip_text, char* port_text, const int if_mode) {
 	GameType type;
 	std::string addr;
 	uint16_t port;
 
 	/* Check if IP address and port are in valid forms */
 	if (check_ip_ver(ip_text) < 0) {
-		throw std::invalid_argument("Invalid IP address");
+		throw std::invalid_argument("Invalid IP address.");
 	}
 	if (port_to_num(port_text) < 0) {
-		throw std::invalid_argument("Invalid port");
+		throw std::invalid_argument("Invalid port.");
 	}
 
 	/* From here on, we assume that the IP and port are valid */
@@ -30,9 +32,9 @@ GameType check_server(char* ip_text, char* port_text) {
 	std::string code = connect_code::encode(addr, std::to_string(port));
 
 	/* Create server socket and wait for client to connect */
-	Server* server = new Server(4, ES_UDP, addr.data(), port);
+	Server* server = new Server(ES_UDP, addr.data(), port);
 	server->create_socket();
-	display_text_centered("Your code is " + code + "\nWaiting for connection...");
+	display_text("Your code is " + code + "\nWaiting for connection...", if_mode);
 	std::string response = "";
 	char* temp_response = NULL;
 	/* Wait for the client to connect. Since recvAll returns a char*, we need to create a temporary variable to check for NULL. 
@@ -43,33 +45,31 @@ GameType check_server(char* ip_text, char* port_text) {
 	response = std::string(temp_response);
 	
 	server->sendAll("U2");
-	display_text_centered("Connection received from " + server->get_peer_addr());
-	Timer timer = timer_init(3); 
-	while (!timer_done(timer)); // Wait for five seconds
+	display_text("Connection received from " + server->get_peer_addr(), if_mode);
 	
 	type.mode = M_SERVER;
 	type.netsock = server;
 	return type;
 }
 
-GameType check_client(char* code_text) {
+GameType check_client(char* code_text, const int if_mode) {
 	GameType type;
 	std::vector<std::string> addr_port;
 	std::string connect_code = std::string(code_text); /* The connect code is a special string, that contains the server address and port. It is given by the server. */
 	try {
 		addr_port = connect_code::decode(connect_code);
-		Client* client = new Client(4, ES_UDP, addr_port[0].data(), std::stoi(addr_port[1]));
+		if (check_ip_ver(addr_port[0].data()) < 0) {
+			throw std::invalid_argument("Invalid code entered.");
+		}
+		Client* client = new Client(ES_UDP, addr_port[0].data(), std::stoi(addr_port[1]));
 		client->create_socket();
 		/* Send a specific message to the server, and wait for the appropriate response, to know that the server is ready */
 		client->sendAll("GG");
-//		display_text_centered("Connecting...");
 		std::string msg_from_server = client->recvAll();
 		if (msg_from_server == "U2") {
-			display_text_centered("Connection made");
-			Timer timer = timer_init(3);
-			while (!timer_done(timer));
+			display_text("Connection made", if_mode);
 		} else {
-			throw EXCEPT_WRONGRESPONSE;
+			throw std::invalid_argument("Server didn't respond with correct message.");
 		}
 		type.mode = M_CLIENT;
 		type.netsock = client;

client.cpp

@@ -1,6 +1,5 @@
 #include <fcntl.h>
 #include "includes/client.hpp"
-#include "includes/exception_consts.hpp"
 #include "includes/sock.hpp"
 #include "includes/easysock.h"
 

connect_code.cpp

@@ -1,10 +1,21 @@
+#include <iostream>
 #include <string>
 #include <vector>
+#include <algorithm>
 #include <iomanip>
 #include <cstring>
 #include <cstdint>
 #include "includes/connect_code.hpp"
 #include "includes/numeric_base.hpp"
+#include "includes/easysock.h"
+
+#if defined(_WIN32)
+	#include <In6addr.h>
+	#include <Ws2tcpip.h>
+#else
+	#include <sys/socket.h>
+	#include <arpa/inet.h>
+#endif
 
 namespace connect_code {
 
@@ -44,13 +55,69 @@ namespace connect_code {
 		uint32_t addr_val = (std::stoul(octets[0]) << 24) + (std::stoul(octets[1]) << 16) + (std::stoul(octets[2]) << 8) + (std::stoul(octets[3]));
 		return std::to_string(addr_val);
 	}
+	
+	/* Expand an IPv6 address (expand '::' into ':0000:', for example).
+	This is done by first converting the address into a binary representation,
+	and then printing every character of the binary representation into a string. */
+	std::string expand_ip6_addr(std::string addr) {
+		char ip6_string[40]; // 32 characters + 7 colons
+		struct in6_addr* ip6_s_ptr = (struct in6_addr *)malloc(sizeof(in6_addr)); // Struct pointer, to store the binary representation of the address
+		inet_pton(AF_INET6, addr.data(), ip6_s_ptr); // Convert the string representation into a binary form
+		
+		/* This abomination, converts the binary representation into a string.
+		It uses sprintf to print every byte in the binary representation into a string. 
+		The bytes are formatted as 2-character hexadecimal values. */
+		sprintf(ip6_string,
+			"%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x", 
+			ip6_s_ptr->s6_addr[0], ip6_s_ptr->s6_addr[1],
+			ip6_s_ptr->s6_addr[2], ip6_s_ptr->s6_addr[3],
+			ip6_s_ptr->s6_addr[4], ip6_s_ptr->s6_addr[5],
+			ip6_s_ptr->s6_addr[6], ip6_s_ptr->s6_addr[7],
+			ip6_s_ptr->s6_addr[8], ip6_s_ptr->s6_addr[9],
+			ip6_s_ptr->s6_addr[10], ip6_s_ptr->s6_addr[11],
+			ip6_s_ptr->s6_addr[12], ip6_s_ptr->s6_addr[13],
+			ip6_s_ptr->s6_addr[14], ip6_s_ptr->s6_addr[15]);
+			
+		return std::string(ip6_string);
+	}
 
 
 	std::string encode(std::string address, std::string port) {
-		/* Convert the address to decimal, and convert that to hex */
-		std::string addr_coded = dotted_dec_to_dec(address);
-		addr_coded = base_convert(addr_coded, 10, 32);
-
+		std::string addr_coded = "";
+		if (check_ip_ver(address.data()) == 4) {
+			/* First, convert the address into a decimal format. Then convert this decimal format
+			into base-32, and also convert the port number into base-32. Join these together with
+			a "_". */
+			
+			/* I don't really have a reason to use my own function (dotted_dec_to_dec() 
+			and dec_to_dotted_dec()), to convert the IP address from text to binary.
+			The inet_pton() and inet_ntop() functions can do this just fine, and also
+			take care of edge cases. Maybe someday, I might change this code. I could probably
+			repurpose the functions for something else, though. */
+			
+			/* First, convert the address into a 32-bit integer (the integer is stored as a string).
+			Then, convert the address into base-32. */
+			addr_coded = dotted_dec_to_dec(address);
+			addr_coded = base_convert(addr_coded, 10, 32);
+		}
+		if (check_ip_ver(address.data()) == 6) {
+			/* First, expand the address into the full 39-character format (32 hex values + 7 colons).
+			Then, tokenize the string, using colons as the delimiters.
+			Finally, take each token in the string, and convert it from base-16 to base-32, appending a '-' as a delimiter. */
+			std::string addr_expanded = expand_ip6_addr(address);
+			std::vector<std::string> addr_tokenized = tokenize_str(addr_expanded, ":");
+			
+			for (size_t i = 0; i < addr_tokenized.size()-1; i++ ) {
+				addr_coded += base_convert(addr_tokenized[i], 16, 32);
+				addr_coded += "-";
+			}
+			addr_coded += base_convert(addr_tokenized[addr_tokenized.size()-1], 16, 32); // I put this outside the loop, because I don't want a hyphen after it
+			
+			/* TODO - Check if the IP address is actually converted properly, and test if the server socket is created correctly.
+			 Also do the same for client side, and check client-server connection. */
+						
+		}
+		
 		/* Convert the port to hex */
 		std::string port_coded = base_convert(port, 10, 32);
 		std::string ret_val = addr_coded + "_" + port_coded;
@@ -61,22 +128,58 @@ namespace connect_code {
 
 	std::vector<std::string> decode(std::string connect_code) {
 		if (connect_code.find("_") == std::string::npos) {
-			throw std::invalid_argument("Invalid code entered.");
+			throw std::invalid_argument("Invalid code entered."); // There must be an underscore, to separate the address part from the port part
 		}
+		
+		int ip_ver = 0;
+		if (connect_code.find("-") != std::string::npos) {
+			ip_ver = 6; // If the string contains hyphens, it must be an IPv6 address encoding.
+		} else {
+			ip_ver = 4;
+		}
+		
 		std::vector<std::string> result = tokenize_str(connect_code, "_"); /* Split the string into address and port */
-		std::string address = result[0]; /* Address (in base 16) */
-		std::string port = result[1]; /* Port (in base 16) */
-
-		/* Base 16 to base 10 - These lines convert the string to a base 10 number, and convert the result back into a string */
-		address = std::to_string(std::stoul(address, 0, 32));
-		port = std::to_string(std::stoul(port, 0, 32));
-
-		/* Convert decimal address to dotted decimal */
-		address = dec_to_dotted_dec(address);
-
+		std::string address = result[0]; /* Address (in base 32) */
+		std::string port = result[1]; /* Port (in base 32) */
+		
 		std::vector<std::string> ret_val;
-		ret_val.push_back(address);
-		ret_val.push_back(port);
+		
+		/* The IPv6 and IPv4 encodings are slightly different - I use a hyphen as a delimiter
+		for IPv6, while there is no delimiter for IPv4. This is why I need to check if the address
+		is IPv4 or IPv6. */
+		if (ip_ver == 4) {
+			/* Base 32 to base 10 - These lines convert the string to a base 10 number, and convert the result back into a string */
+			address = std::to_string(std::stoul(address, 0, 32));
+			port = std::to_string(std::stoul(port, 0, 32));
+
+			/* Convert decimal address to dotted decimal */
+			address = dec_to_dotted_dec(address);
+
+			/* Create a vector containing the address and the port, which will be returned */
+			ret_val.push_back(address);
+			ret_val.push_back(port);
+		} else {
+			/* IPv6 */
+			/* There are three main steps to decoding for IPv6:
+			1. Tokenize the address using the delimiter set while encoding ('-', in my case).
+			2. Convert each token from base-32 to base-16.
+			3. Join the string vector back together into a string, this time using ':' as a delimiter. This will give us our IP address. */
+
+			std::string conv_addr = ""; // Stores the final address
+			std::vector<std::string> address_tokenized = tokenize_str(address, "-"); // Step 1
+			
+			for (size_t i = 0; i < address_tokenized.size()-1; i++) {
+				address_tokenized[i] = base_convert(address_tokenized[i], 32, 16); // Step 2
+				conv_addr += address_tokenized[i] + ":"; // Step 3
+			}
+			conv_addr += base_convert(address_tokenized[address_tokenized.size()-1], 32, 16); // Add the last token
+
+			port = std::to_string(std::stoul(port, 0, 32));
+
+			ret_val.push_back(conv_addr);
+			ret_val.push_back(port);
+		}
+		
 		return ret_val;
 	}
 }

create_release_mingw.sh

@@ -2,17 +2,28 @@
 
 # This script copies required DLLs, and the application itself into a folder called 'release'. It only runs on MinGW.
 
+set -o errexit # Stop executing when a command fails
 BASE_DIR=$(dirname $0)
 REL_DIR="$BASE_DIR/release/dist"
+RAYLIB_DLL="$BASE_DIR/build/subprojects/raylib/libraylib.dll"
 
 mkdir -p "$REL_DIR"
 
-# Parse the output of the 'ldd' command, and create a file with the required DLL paths.
-ldd build/pong.exe | awk ' NF == 4 {print $3}' > "$BASE_DIR/tmp_file.txt"
+# Set up the build directory
+meson setup build/
+
+# Build the application
+meson compile -C build/
+
+# Parse the output of the 'ldd' command (using only DLLs that are found) and create a file with the required DLL paths.
+ldd build/pong.exe | awk ' NF == 4 {print $3}' | grep -i "dll" > "$BASE_DIR/tmp_file.txt"
 
 # Copy the required DLLs.
 cp $(cat "$BASE_DIR/tmp_file.txt") "$REL_DIR"
 
+# Copy the raylib DLL, if it does not exist in the directory
+cp -n "$RAYLIB_DLL" "$REL_DIR"
+
 # Copy the executable itself
 cp "$BASE_DIR/build/pong" "$REL_DIR"
 

create_static_linux.sh

@@ -0,0 +1,26 @@
+#!/bin/bash
+
+# This script creates and packages a statically-linked build of the game, for Linux.
+# It must be placed in the root of the source code.
+
+set -o errexit # Stop executing when a command fails
+BASE_DIR=$(dirname 0)
+REL_DIR="$BASE_DIR/release/static/pong"
+
+mkdir -p "$REL_DIR"
+
+# Set the default build target to static
+meson configure -Ddefault_library=static "$BASE_DIR/build/"
+
+# Build the application
+meson compile -C "$BASE_DIR/build/"
+
+# Package the application:
+# 1. Copy the executable to REL_DIR
+# 2. Create a tarball after cd'ing into the parent directory.
+
+cp "$BASE_DIR/build/pong" "$REL_DIR"
+tar -C "$BASE_DIR/release/static" -czf "$BASE_DIR/release/pong.tar.gz" "pong/"
+
+# Reset default build target to shared
+meson configure -Ddefault_library=shared "$BASE_DIR/build/"

display_text.cpp

@@ -0,0 +1,13 @@
+#include "includes/display_text.hpp"
+#include <iostream>
+#include <string>
+
+void display_text(std::string to_disp, const int if_mode) {
+	if (if_mode == IF_CLI) {
+		std::cout << to_disp << std::endl;
+	}
+	if (if_mode == IF_GUI) {
+		display_text_raygui(to_disp);
+	}
+	return;
+}

easysock.c

@@ -52,22 +52,23 @@ SOCKET create_socket(int network, char transport) {
 
 	int newSock = socket(domain,type,0);
 
-	/* Set REUSEADDR flag, allowing program to be run twice */
-	int set_opt = 1;
-	setsockopt(newSock, SOL_SOCKET, SO_REUSEADDR, (char *)&set_opt, sizeof(set_opt));
-
+	/* Set REUSEADDR flag for TCP, allowing program to be run twice */
+	if (transport == ES_TCP) {
+		int set_opt = 1;
+		setsockopt(newSock, SOL_SOCKET, SO_REUSEADDR, (char *)&set_opt, sizeof(set_opt));
+	}
 	return newSock;
 }
 
 
-int create_addr(int network, const char* address, int port,struct sockaddr* dest) {
+int create_addr(int network, const char* address, int port,struct sockaddr_storage* dest) {
 	if (network == 4) {
 		struct sockaddr_in listen_address;
 		
 		listen_address.sin_family = AF_INET;
 		listen_address.sin_port = htons(port);
 		inet_pton(AF_INET,address,&listen_address.sin_addr);
-		memcpy(dest,&listen_address,sizeof(listen_address));
+		memcpy((struct sockaddr *)dest,&listen_address,sizeof(listen_address));
 		return 0;	
 
 	} else if (network == 6) {
@@ -75,7 +76,7 @@ int create_addr(int network, const char* address, int port,struct sockaddr* dest
 		listen_ipv6.sin6_family = AF_INET6;
 		listen_ipv6.sin6_port = htons(port);
 		inet_pton(AF_INET6,address,&listen_ipv6.sin6_addr);
-		memcpy(dest,&listen_ipv6,sizeof(listen_ipv6));
+		memcpy((struct sockaddr_in6 *)dest,&listen_ipv6,sizeof(listen_ipv6));
 		return 0;
 
 	} else {
@@ -84,7 +85,7 @@ int create_addr(int network, const char* address, int port,struct sockaddr* dest
 		
 }
 
-SOCKET create_local (int network, char transport, const char* address, int port,struct sockaddr* addr_struct) {
+SOCKET create_local (int network, char transport, const char* address, int port,struct sockaddr_storage* addr_struct) {
 	int socket = create_socket(network,transport);
 	if (socket < 0) {
 		return (-1 * errno);
@@ -103,14 +104,14 @@ SOCKET create_local (int network, char transport, const char* address, int port,
 	This should be set to the size of 'sockaddr_in' for IPv4, and 'sockaddr_in6' for IPv6.
 	See https://stackoverflow.com/questions/73707162/socket-bind-failed-with-invalid-argument-error-for-program-running-on-macos */
 
-	int i = bind (socket,addr_struct,(socklen_t)addrlen);
+	int i = bind (socket,(struct sockaddr *)addr_struct,(socklen_t)addrlen);
 	if (i < 0) {
 		return (-1 * errno);
 	}
 	return socket;
 }
 
-SOCKET create_remote (int network,char transport, const char* address,int port,struct sockaddr* remote_addr_struct) {
+SOCKET create_remote (int network,char transport, const char* address,int port,struct sockaddr_storage* remote_addr_struct) {
 
 	struct addrinfo hints;  /* Used to tell getaddrinfo what kind of address we want */
 	struct addrinfo* results; /* Used by getaddrinfo to store the addresses */
@@ -130,7 +131,7 @@ SOCKET create_remote (int network,char transport, const char* address,int port,s
 		if (err_code != 0) {
 			return (-1 * err_code);
 		}
-		remote_addr_struct = results->ai_addr;
+		remote_addr_struct = (struct sockaddr_storage *)results->ai_addr;
 		network = inet_to_int(results->ai_family);
 	} else {
 	        create_addr(network,address,port,remote_addr_struct);

includes/check_input.hpp

@@ -17,12 +17,14 @@ typedef struct {
 
 /* This function checks the IP address and port passed to it, and returns a struct,
 that contains information about the game mode, and contains the server socket.
-It assumes that both ip_text and port_text are non-null
+It assumes that both ip_text and port_text are non-null.
+Any errors are printed using the display_text function, with the given if_type.
 TODO - Add better error checking. */
-GameType check_server(char* ip_text, char* port_text);
+GameType check_server(char* ip_text, char* port_text, const int if_type);
 
 /* NOT IMPLEMENTED YET - This function checks the code given to it, and returns a struct
-that contains information about the game mode, and contains the client socket. */
-GameType check_client(char* code);
+that contains information about the game mode, and contains the client socket.
+Any errors are printed using the display_text function, with the given if_type. */
+GameType check_client(char* code, const int if_type);
 
 #endif

includes/client.hpp

@@ -15,7 +15,7 @@ public:
 	~Client();
 
 	/* Normal constructor that calls the parent constructor to set the given values */
-	Client(int ip_ver, char protocol, const char* address, int port) : Sock(ip_ver, protocol, address, port) {}
+	Client(char protocol, const char* address, int port) : Sock(protocol, address, port) {}
 
 	void create_socket() override;
 

includes/display_text.hpp

@@ -0,0 +1,10 @@
+#include "includes/raygui_helpers.hpp"
+
+/* Constants that can be used by caller function. */
+const int IF_CLI = 1;
+const int IF_GUI = 2;
+
+/* This function is used to display text. It is used to abstract the differences
+ between GUI invocation and CLI invocation. The if_mode parameter is used to 
+ determine whether the game was launched from GUI or CLI. */
+void display_text(std::string to_disp, const int if_mode);

includes/easysock.h

@@ -5,11 +5,14 @@ extern "C" {
 #define EASYSOCK_H_
 
 #ifdef _WIN32
+	#define NOGDI             // All GDI defines and routines
+        #define NOUSER            // All USER defines and routines
+        #define WIN32_LEAN_AND_MEAN
 	#include <winsock2.h>
 	#include <winsock.h>
 	#include <ws2tcpip.h>
 #endif
-#ifdef __unix__
+#if defined(__unix) || defined(__unix) || (defined(__APPLE__) && defined(__MACH__))
 	#include <sys/types.h>
 	#include <sys/socket.h>
 	#include <netdb.h>
@@ -47,7 +50,7 @@ and dest is a pointer to the sockaddr struct that will be filled in.
 The function returns with -202 if the network parameter contained neither '4'
 nor '6'. */
 
-int create_addr(int network, const char* address, int port,struct sockaddr* dest);
+int create_addr(int network, const char* address, int port,struct sockaddr_storage* dest);
 
 
 
@@ -57,7 +60,7 @@ same as above.
 
 It prints the error returned by 'bind' if something went wrong, and returns ( -1 * errno ).*/
 
-SOCKET create_local (int network, char transport, const char* address, int port,struct sockaddr* addr_struct);
+SOCKET create_local (int network, char transport, const char* address, int port,struct sockaddr_storage* addr_struct);
 
 
 /* This function utilizes the same functions as 'create_local' but _connects_ to the
@@ -66,7 +69,7 @@ as above. This function needs an empty 'sockaddr *' structure passed to it, whic
 
 If something goes wrong, this function returns with ( -1 * errno ). */
 
-SOCKET create_remote (int network,char transport, const char* address,int port,struct sockaddr* remote_addr_struct);
+SOCKET create_remote (int network,char transport, const char* address,int port,struct sockaddr_storage* remote_addr_struct);
 
 /* check_ip_ver - This function checks if the given string is an IPv4 address (returns 4), 
 IPv6 address (returns 6) or neither (returns -1). */

includes/raygui_helpers.hpp

@@ -4,6 +4,8 @@
 
 /* Display the given text, centered on the screen, as a label.
 NEEDS RAYGUI LIBRARY. */
-void display_text_centered(std::string to_disp);
+void display_text_raygui(std::string to_disp);
 
+/* Display the given string, and exit the game after 'time' seconds. */
+void display_and_exit_raygui(std::string to_disp, int time);
 #endif

includes/server.hpp

@@ -15,7 +15,7 @@ public:
 	/* Constructors */
 	Server() {}
 
-	Server(int ip_ver, char protocol, const char* address, int port) : Sock(ip_ver, protocol, address, port) {}
+	Server(char protocol, const char* address, int port) : Sock(protocol, address, port) {}
 
 	/* Destructor */
 	~Server();

includes/sock.hpp

@@ -2,7 +2,7 @@
 #define _SOCK_CLASS
 
 #include <string>
-#ifdef __unix__
+#if defined(__unix__) || defined(__unix) ||(defined(__APPLE__) && defined(__MACH__))
 	#include <sys/socket.h>
 #endif
 #ifdef _WIN32
@@ -23,7 +23,7 @@ protected:
 	int port;
 	int sock_fd;
 	std::string address;
-	struct sockaddr* dest;
+	struct sockaddr_storage* dest;
 	socklen_t addrlen;
 	int other_socket; // The peer socket (the client if this socket is a server, and the server if this socket is a client) */
 
@@ -38,7 +38,7 @@ public:
 	virtual ~Sock();
 
 	/* Regular constructor - defined in sock.cpp */
-	Sock(int ip_ver, char protocol, const char* address, int port);
+	Sock(char protocol, const char* address, int port);
 
 	/* Method to send data in 'to_send' through the 'other_socket' socket */
 	void sendAll(std::string to_send);
@@ -49,7 +49,8 @@ public:
 	/* Method to receive data sent to the 'other_socket' socket */
 	char* recvAll();
 
-	/* Non-blocking receive method - calls the method above after polling for data */
+	/* Non-blocking receive method - calls the method above after polling for data. Returns
+	an empty string if there is nothing to read. */
 	char* recvAllNB();
 
 	/* Returns socket identifier */

main.cpp

@@ -14,9 +14,11 @@
 
 
 #include <iostream>
+#define _USE_MATH_DEFINES
 #include <cmath>
 #include <cstring>
 #include <ctime>
+#include <cerrno>
 #include <sstream>
 #include "includes/raylib-cpp/raylib-cpp.hpp"
 
@@ -30,7 +32,7 @@
 #include "includes/server.hpp"
 #include "includes/exception_consts.hpp"
 #include "includes/check_input.hpp"
-#include "includes/raygui_helpers.hpp"
+#include "includes/display_text.hpp"
 #include "includes/easysock.h"
 #include "includes/serialization.h"
 #include "includes/timer.h"
@@ -47,6 +49,24 @@ const float BASE_BOUNCE_RAD = (BASE_BOUNCE_DEG / 180.0) * M_PI;
 const float BASE_SPEED_COMPONENTS = 15;
 const float BASE_SPEED = sqrt(powf(BASE_SPEED_COMPONENTS, 2) * 2);
 
+std::string HELP_TEXT = "\nnetpong - A networked pong game for the internet era.\n"
+			"\n"
+			"Usage: \n"
+			"netpong [MODE] [ADDRESS PORT]|[CODE]\n"
+			"\n"
+			"MODE: \n"
+			"-S : Server mode. Starts a server to allow the other player to connect.\n"
+			"IP address and port must be specified.\n"
+			"\n"
+			"-C: Client mode. Connects to a server, using the provided connection code.\n"
+			"\n"
+			"If no mode is specified, single player mode is used as default.\n"
+			"\n"
+			"CONTROLS:"
+			"\'W\' and \'S\' control left paddle (AKA client paddle)\n"
+			"Up and Down arrow keys control right paddle (AKA server paddle)\n";
+			
+
 /* Simple function to return 1 if a value is positive, and -1 if it is negative */
 int signum(int num) {
 	int retval = 0;
@@ -74,138 +94,68 @@ raylib::Vector2 changeVelocityAfterCollision(Paddle paddle, Ball ball) {
 	return raylib::Vector2(new_x_vel, new_y_vel);
 }
 
-/* This function checks the command-line arguments passed to the program.
-It then decides whether the game is in Server or Client mode (or neither), and
-instantiates the appropriate object. The (uninitialized) objects are passed to the
-function as pointers. It returns a GameType struct, that indicates whether the game
-is in server, client or single player mode, and contains the appropriate socket object. */
-
-GameType check_server_client(int argc, char** argv) {
-	std::string connect_code;
-	std::vector<std::string> addr_port; /* Vector to store (IPv4) address and port */
-	GameType type;
-
-	if (argc < 2) { /* Game was not started in client or server mode */
-		type.mode = M_SINGLE;
-		type.netsock = nullptr;
-		return type;
+/* Checks the number and type of the command-line arguments. Throws an exception
+   if the args are invalid. DOES NOT PROCESS VALID ARGUMENTS. */
+void check_num_args(int argc, char** argv) {
+	if (argc > 4) {
+		throw std::invalid_argument("ARGUMENT ERROR: Too many arguments. To view syntax, use -h or --help.");
 	}
-
-	/* GAME STARTED IN CLIENT MODE */
-	if (strcmp(argv[1],"-C") == 0) {
-		if (argc < 3) { /* No address was provided */
-			throw EXCEPT_TOOFEWARGS;
-		}
-		connect_code = std::string(argv[2]); /* The connect code is a special string, that contains the server address and port. It is given by the server. */
-		try {
-			addr_port = connect_code::decode(connect_code);
-			Client* client = new Client(4, ES_UDP, addr_port[0].data(), std::stoi(addr_port[1]));
-			client->create_socket();
-			/* Send a specific message to the server, and wait for the appropriate response, to know that the server is ready */
-			client->sendAll("GG");
-			std::string msg_from_server = client->recvAll();
-			if (msg_from_server == "U2") {
-				std::cout << "Connection made. Waiting for server to begin game..." << std::endl;
-			} else {
-				throw EXCEPT_WRONGRESPONSE;
+	if (argc > 1) { // Either server or client mode
+		if (std::string(argv[1]) == "-S") {
+			if (argc < 4) { // Server mode but no address and/or port
+				throw std::invalid_argument("ARGUMENT ERROR: Server mode specified without any address or port.");
 			}
-			type.mode = M_CLIENT;
-			type.netsock = client;
-			return type;
-		} catch (int e) {
-			throw;
-		} catch (std::exception& e) {
-			throw;
 		}
-	}
-
-	/* GAME STARTED IN SERVER MODE */
-	else if (strcmp(argv[1],"-S") == 0) {
-		std::string addr;
-		uint16_t port;
-
-		/* No IP address or port specified */
-		if (argc < 3) {
-			throw EXCEPT_TOOFEWARGS;
+		else if (std::string(argv[1]) == "-C") {
+			 if (argc < 3) { // Client mode but no code
+				throw std::invalid_argument("ARGUMENT ERRROR: Client mode specified without any code.");
+			}
 		}
-
-		/* IP address but no port */
-		else if (argc < 4) {
-			std::cout << "No port specified, using 6500..." << std::endl;
-			addr = std::string(argv[2]);
-			port = 6500;
+		else if (std::string(argv[1]) == "-h" || std::string(argv[1]) == "--help") {
+			throw std::invalid_argument(HELP_TEXT); // I am abusing the exception mechanism here, so that I can ensure that the caller quits the program after printing the help message.
 		} else {
-			addr = std::string(argv[2]);
-			port = std::stoi(std::string(argv[3]));
+			throw std::invalid_argument("Unrecognized argument.");
 		}
-
-		/* Check if IP is valid */
-		if (check_ip_ver(addr.data()) < 0) {
-			throw EXCEPT_INVALIDIP;
-		}
-
-		std::string code = connect_code::encode(addr, std::to_string(port));
-		std::cout << "Your code is " << code << std::endl;
-
-		/* Create server socket and wait for client to connect */
-		Server* server = new Server(4, ES_UDP, addr.data(), port);
-		server->create_socket();
-		std::cout << "Waiting for connection..." << std::endl;
-		std::string response = "";
-		char* temp_response = NULL;
-		/* Wait for the right client to connect. Since recvAll returns a char*, we need to create a temporary variable to check for NULL.
-		TODO - Check that the client actually sends 'GG'. */
-		do {
-			temp_response = server->recvAll();
-		} while (temp_response == NULL);
-		response = std::string(temp_response);
-
-		std::cout << "Connection received from " << server->get_peer_addr() << std::endl;
-		server->sendAll("U2");
-		type.mode = M_SERVER;
-		type.netsock = server;
-		return type;
 	}
-
-	else {
-		throw EXCEPT_INVALIDARGS;
-	}
-
+	return;
 }
 
 int main(int argc, char** argv) {
-	/* Check if game was started in server or client mode, and set appropriate variables */
-
-	/* GameType struct, to define whether the game is in single or muilti-player mode, and
+	/* Check the number and validity of command-line arguments. Invalid arguments
+	will throw an exception. */
+	try {
+		check_num_args(argc, argv);
+	} catch (std::invalid_argument& inv) {
+		std::cout << inv.what() << std::endl;
+		return -1;
+	}
+	
+	/* From here on, we assume that:
+		a. The program was started with no arguments (User is prompted in GUI), OR
+		b. The program was started in server mode, and an additional was given, OR
+		c. The program was started in client mode, and an additional argument was given. */
+	
+	/* GameType struct, to define whether the game is in single or multi-player mode, and
 	to hold the appropriate socket */
 	GameType type;
-
-	try {
-		type = check_server_client(argc, argv);
-	} catch(int e) {
-		if (e == EXCEPT_TOOFEWARGS) {
-			std::cout << "Started in client mode, but no address was specified." << std::endl;
-			return -1;
+	
+	/* Check if game was started in server or client mode, and call the appropriate function to process the arguments.
+	If game was started in single-player mode (i.e. with no arguments), then the user is prompted in the GUI. */
+	try { // I put this try-catch block outside the if-statement because the exception handling is the same for both client and server.
+		if (argc > 1) { // Server or client mode
+			if (std::string(argv[1]) == "-S") { // Server mode
+				type = check_server(argv[2], argv[3], IF_CLI);
+			}
+			if (std::string(argv[1]) == "-C") { // Client mode
+				type = check_client(argv[2], IF_CLI);
+			}
 		}
-		if (e == EXCEPT_INVALIDARGS) {
-			std::cout << "Invalid argument." << std::endl;
-			return -2;
-		}
-		if (e == EXCEPT_INVALIDIP) {
-			std::cout << "Invalid IP address provided." << std::endl;
-			return -5;
-		}
-		if (e == EXCEPT_WRONGRESPONSE) {
-			std::cout << "The server didn't respond with the correct message. Are you sure you have used the right server?" << std::endl;
-			return -6;
-		}
-		else {
-			std::cout << strerror(e) << std::endl;
-			return -7;
-		}
-	} catch(std::invalid_argument& inv) {
-			std::cout << inv.what() << std::endl;
-			return -8;
+	} catch (std::invalid_argument& inv) {
+		std::cout << inv.what() << std::endl;
+		return -1;
+	} catch (int err) {
+		std::cout << strerror(err) << std::endl;
+		return -1;
 	}
 
 	/* Initialize window and other variables */
@@ -239,6 +189,10 @@ int main(int argc, char** argv) {
 		bool button_pressed = false; // Indicates whether the submit button has been pressed
 		
 		while (button_pressed == false) {
+			if (WindowShouldClose()) {
+				CloseWindow();
+				return 0;
+			}
 			BeginDrawing();
 				ClearBackground(BLACK);
 				GuiLabel(Rectangle{(WIDTH/2)-(label_size.x/2), (HEIGHT/8), label_size.x, label_size.y}, text_to_display); // Label to display text on top
@@ -281,6 +235,11 @@ int main(int argc, char** argv) {
 			bool editing_ip = false; // Indicates whether the IP address text box is being edited
 			bool editing_port = false; // Indicates whether the port text box is being edited
 			while (button_pressed == false || ((strlen(ip_text) == 0) || (strlen(port_text) == 0))) {
+				if (WindowShouldClose()) {
+					CloseWindow();
+					return 0;
+				}
+				
 				BeginDrawing();
 					ClearBackground(BLACK);
 					/* Label and text box for IP address */
@@ -305,12 +264,16 @@ int main(int argc, char** argv) {
 			}
 			
 			try {
-				type = check_server(ip_text, port_text);
+				type = check_server(ip_text, port_text, IF_GUI);
+			} catch (int e) {
+				display_and_exit_raygui(std::string(std::strerror(e)) + "\nClosing game...", 2); // The server constructor throws the errno if it cannot create a socket
+				free(ip_text);
+				free(port_text);
+				return -1;
 			} catch (std::invalid_argument& inv) {
-				display_text_centered(std::string(inv.what()) + "\nClosing game...");
-				Timer timer = timer_init(2); // Wait for two seconds
-				while (!timer_done(timer));
-				CloseWindow(); // Close and exit
+				display_and_exit_raygui(std::string(inv.what()) + "\nClosing game...", 2);
+				free(ip_text);
+				free(port_text);
 				return -1;
 			}
 			free(ip_text);
@@ -323,6 +286,11 @@ int main(int argc, char** argv) {
 			const char* code_label = "Enter code:";
 			bool editing_code = false; // Indicates whether the port text box is being edited
 			while (button_pressed == false || ((strlen(code_text) == 0))) {
+				if (WindowShouldClose()) {
+					CloseWindow();
+					return 0;
+				}
+				
 				BeginDrawing();
 					ClearBackground(BLACK);
 					/* Label and text box for IP address */
@@ -335,8 +303,15 @@ int main(int argc, char** argv) {
 					button_pressed = GuiButton(Rectangle{(WIDTH/2) - (box_size.x/2), (HEIGHT/2) + (HEIGHT/6), box_size.x, box_size.y}, "Connect");
 				EndDrawing();
 			}
-			
-			type = check_client(code_text);
+			try {
+				type = check_client(code_text, IF_GUI);
+			} catch (int e) {
+				display_and_exit_raygui(std::string(std::strerror(e)) + "\nClosing game...", 2); // The client constructor throws the errno if it cannot create a socket
+				return -1;
+			} catch (std::invalid_argument& inv) {
+				display_and_exit_raygui(std::string(inv.what()) + "\nClosing game...", 2);
+				return -1;
+			}
 			free(code_text);		
 		}
 	}
@@ -376,11 +351,18 @@ int main(int argc, char** argv) {
 				}
 			}
 
-			/* For client (wait for start message from server) */
+			/* For client (wait for start or quit message from server): When the peer quits the
+			 game, it sends a serialized struct, containing all zeros, with the last bit turned
+			 on as a flag. We catch this zero bit, as it indicates that the peer quit the game. */
 			if (type.mode == M_CLIENT) {
 				do {
 					response = type.netsock->recvAll();
-				} while (response[0] != 'S');
+				} while (response[0] != 'S' && response[0] != 0);
+				if (response[0] == 0) {
+					CloseWindow();
+					std::cout << "Peer unexpectedly quit game." << std::endl;
+					return -1;
+				}
 				game_started = true;
 				std::cout << "Game has been started by server." << std::endl;
 			}

meson.build

@@ -1,5 +1,6 @@
 project('Pong', ['cpp', 'c'], version: '0.1')
 add_global_arguments('-g', '-Wall', '-pedantic', '-Wno-unused-function', '-Wno-narrowing', language : ['cpp', 'c'])
+add_global_arguments('-std=c++11', language: ['cpp'])
 compiler = meson.get_compiler('cpp')
 cmake = import('cmake')
 
@@ -28,12 +29,12 @@ endif
 	ws2_dep = compiler.find_library('ws2_32', required: false)
 	winmm = compiler.find_library('winmm', required: false)
 if build_machine.system() == 'windows'
-	add_global_arguments('-Wl,--subsystem,windows', '-mwindows', language: ['cpp', 'c']) # Prevent opening console when game is run
+	add_project_arguments('-Wl,--subsystem,windows', '-mwindows', language: ['cpp', 'c']) # Prevent opening console when game is run
 
 endif
 
-executable('pong', 
-	'main.cpp', 'sock.cpp','paddle.cpp', 'ball.cpp', 'numeric_base.cpp', 'connect_code.cpp', 'server.cpp', 'client.cpp', 'check_input.cpp', 'raygui_helpers.cpp',
+executable('pong',
+	'main.cpp', 'sock.cpp','paddle.cpp', 'ball.cpp', 'numeric_base.cpp', 'connect_code.cpp', 'server.cpp', 'client.cpp', 'check_input.cpp', 'raygui_helpers.cpp', 'display_text.cpp',
 	'serialization.c', 'timer.c', 'easysock.c',
 	dependencies: [raylib, ws2_dep, winmm]
 )

numeric_base.cpp

@@ -1,6 +1,7 @@
 #include "includes/numeric_base.hpp"
 #include <string>
 #include <cmath>
+#include <cctype>
 #include <algorithm>
 
 std::string possible_chars = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
@@ -12,10 +13,10 @@ unsigned int to_decimal(std::string num, int from_base) {
 
 	/* Here, we convert 'num' to decimal (base 10) - Find the index of
 	every character in the string, in 'possible_chars' and
-	compute the value using  */
+	compute the value using the position of the character in the number. */
 	for (int i=0; i < (int)num.length(); i++) {
 		current_char = num.at(i);
-		index = possible_chars.find(current_char);
+		index = possible_chars.find(toupper(current_char)); // Convert the character to upper-case, so that the earliest match is detected
 		value += pow(from_base, num.length() - i - 1) * index;
 	}
 
@@ -26,12 +27,17 @@ unsigned int to_decimal(std::string num, int from_base) {
 std::string from_decimal(unsigned int num, int to_base) {
 	std::string return_val;
 	int val = 0;
-	while (num > 0) {
-		val = num % to_base;
-		return_val.push_back(possible_chars[val]);
-		num /= to_base;
+	/* Handle the special case of num being zero: In this case, the result is also zero */
+	if (num == 0) {
+		return_val = "0";
+	} else {
+		while (num > 0) {
+			val = num % to_base;
+			return_val.push_back(possible_chars[val]);
+			num /= to_base;
+		}
 	}
-
+	
 	/* Reverse the string, since we started from the right */
 	std::reverse(return_val.begin(), return_val.end());
 

raygui_helpers.cpp

@@ -1,7 +1,7 @@
 #include "includes/raygui_helpers.hpp"
 #include "includes/raygui/raygui.h"
-
-void display_text_centered(std::string to_disp) {
+#include "includes/timer.h"
+void display_text_raygui(std::string to_disp) {
 	const char* to_disp_cstr = to_disp.c_str();
 	Vector2 label_size = MeasureTextEx(GetFontDefault(), to_disp_cstr, GuiGetStyle(DEFAULT, TEXT_SIZE)+1, GuiGetStyle(DEFAULT, TEXT_SPACING)+1); // The '+1' is there to account for any rounding errors
 	
@@ -11,3 +11,10 @@ void display_text_centered(std::string to_disp) {
 	EndDrawing();	
 	return;
 }
+
+void display_and_exit_raygui(std::string to_disp, int time) {
+	display_text_raygui(to_disp);
+	Timer timer = timer_init(time);
+	while (!timer_done(timer));
+	return;
+}

serialization.c

@@ -2,7 +2,7 @@
 #include <stdlib.h>
 #include <stdbool.h>
 #include <string.h>
-#ifdef __unix__
+#if defined(__unix__) || defined(__unix) || (defined(__APPLE__) && defined(__MACH__))
 	#include <arpa/inet.h>
 #endif
 #ifdef _WIN32

server.cpp

@@ -1,4 +1,4 @@
-#ifdef __unix__
+#if defined(__unix__) || defined(__unix) || (defined(__APPLE__) && defined(__MACH__))
 	#include <sys/socket.h>
 #endif
 #ifdef _WIN32
@@ -7,7 +7,6 @@
 #include <fcntl.h>
 #include "includes/sock.hpp"
 #include "includes/server.hpp"
-#include "includes/exception_consts.hpp"
 #include "includes/connect_code.hpp"
 #include "includes/easysock.h"
 
@@ -44,11 +43,14 @@ char* Server::recvAll() {
 	if (this->ip_ver == 4) {
 		/* FOR IPv4 */
 		struct sockaddr_in* temp_struct = (struct sockaddr_in*)this->dest;
-		/* Convert the s_addr field of the caseted struct to host network-byte, and convert it to a dotted decimal */
+		/* Convert the s_addr field of the casted struct to host network-byte, and convert it to a dotted decimal */
 		peer_addr = connect_code::dec_to_dotted_dec(std::to_string(htonl(temp_struct->sin_addr.s_addr)));
 	} else {
-		/* FOR IPv6 */
-		peer_addr = "IPV6 NOT SUPPORTED YET";
+		/* FOR IPv6 - Use the inet_ntop function, and convert the struct's address into a string */
+		struct sockaddr_in6* temp_struct = (struct sockaddr_in6*)this->dest;
+		char* temp_buf = (char *)malloc(sizeof(char) * (INET6_ADDRSTRLEN + 1));
+		peer_addr = std::string(inet_ntop(AF_INET6, temp_struct->sin6_addr.s6_addr, temp_buf, INET6_ADDRSTRLEN));
+		free(temp_buf);
 	}
 
 	return to_return;
@@ -70,8 +72,11 @@ char* Server::recvAllNB() {
 		/* Convert the s_addr field of the caseted struct to host network-byte, and convert it to a dotted decimal */
 		peer_addr = connect_code::dec_to_dotted_dec(std::to_string(htonl(temp_struct->sin_addr.s_addr)));
 	} else {
-		/* FOR IPv6 */
-		peer_addr = "IPV6 NOT SUPPORTED YET";
+		/* FOR IPv6 - Use the inet_ntop function, and convert the struct's address into a string */
+		struct sockaddr_in6* temp_struct = (struct sockaddr_in6*)this->dest;
+		char* temp_buf = (char *)malloc(sizeof(char) * (INET6_ADDRSTRLEN + 1));
+		peer_addr = std::string(inet_ntop(AF_INET6, temp_struct->sin6_addr.s6_addr, temp_buf, INET6_ADDRSTRLEN));
+		free(temp_buf);
 	}
 
 	return to_return;
@@ -84,7 +89,7 @@ is thrown as an exception. */
 
 void Server::wait_for_peer() {
 	if (this->protocol == ES_TCP) {
-		this->other_socket = accept(this->sock_fd, dest, &addrlen);
+		this->other_socket = accept(this->sock_fd, (struct sockaddr *)dest, &addrlen);
 		if (this->other_socket < 0) {
 			throw errno;
 		}
@@ -96,8 +101,7 @@ called immediately after the constructor. If the socket is TCP, it also sets the
 socket to listen for incoming connections. This function throws an exception if
 the socket could not be created. The excpetion is an integer corresponding to the errno
 of the failing function, and enables the caller to print a corresponding error message by
-'catching' the thrown exception and using strerror().
-This function also sets a timeout of 100ms for UDP sockets */
+'catching' the thrown exception and using strerror().*/
 
 void Server::create_socket() {
 	Sock::create_socket();

sock.cpp

@@ -1,7 +1,6 @@
 #include <cerrno>
 #include <stdexcept>
 #include "includes/sock.hpp"
-#include "includes/exception_consts.hpp"
 #include "includes/easysock.h"
 
 /* Function to create socket. This function doesn't actually create a socket
@@ -9,7 +8,7 @@
 extend this function, and create the appropriate sockets. */
 
 void Sock::create_socket()  {
-	dest = (struct sockaddr *)malloc(sizeof(struct sockaddr));
+	dest = (struct sockaddr_storage *)malloc(sizeof(struct sockaddr_storage));
 	addrlen = sizeof(*dest);
 }
 
@@ -18,11 +17,11 @@ Sock::~Sock() {}
 
 
 /* Constructor - This function initializes the object attributes with the given
-parameters. It throws an exception if an IPv4 address was given, but the type
-given is IPv6 (or the other way around). */
+parameters. The address version (IPv4 or IPv6) is determined based on the given address. */
 
-Sock::Sock(int ip_ver, char protocol, const char* address, int port) {
-	/* Error checking */
+Sock::Sock(char protocol, const char* address, int port) {
+	this->ip_ver = check_ip_ver(address);
+	
 	if (ip_ver != 4 && ip_ver != 6) {
 		throw std::invalid_argument("Invalid IP address type");
 	}
@@ -33,15 +32,9 @@ Sock::Sock(int ip_ver, char protocol, const char* address, int port) {
 		throw std::invalid_argument("Invalid protocol");
 	}
 
-	this->ip_ver = ip_ver;
 	this->protocol = protocol;
 	this->port = port;
 	this->address = std::string(address);
-
-	/* Check to see if the given IP address matches the given ip_ver */
-        if ((check_ip_ver(address) != 6 && ip_ver == 6) || (check_ip_ver(address) != 4 && ip_ver == 4)) {
-		throw std::invalid_argument("Invalid IP address for given type.");
-	}
 }
 
 /* This method sends the given data, through the  'other_sockt' variable.. Client
@@ -55,7 +48,9 @@ void Sock::sendAll(std::string to_send) {
 
 	/* For UDP sockets */
 	if (this->protocol == ES_UDP) {
-		sendto(this->sock_fd, to_send.data(), str_length, 0, dest, addrlen);
+		if (sendto(this->sock_fd, to_send.data(), str_length, 0, (struct sockaddr *)dest, addrlen) == -1) {
+			throw errno;
+		}
 	}
 	/* For TCP sockets */
 	else {
@@ -63,7 +58,7 @@ void Sock::sendAll(std::string to_send) {
 			/* Send the data to the 'other_socket' variable, which should be set by the client and server methods */
 			num_bytes_sent = send(this->other_socket, to_send.substr(total_bytes_sent).c_str(), str_length - total_bytes_sent, 0);
 			if (num_bytes_sent < 0) {
-				throw errno * -1;
+				throw errno;
 			}
 			total_bytes_sent += num_bytes_sent;
 		}
@@ -86,14 +81,17 @@ This function also needs more testing for TCP. */
 char* Sock::recvAll() {
 	int num_bytes_received = 0;
 	int total_bytes_received = 0;
-	char* buffer = (char *)malloc(100);
+	char* buffer = (char *)malloc(150 * sizeof(char));
 	bool has_been_read = false;
 
 	if (this->protocol == ES_UDP) {
-		num_bytes_received = recvfrom(this->sock_fd, buffer, 99, 0, dest, &addrlen);
+		num_bytes_received = recvfrom(this->sock_fd, buffer, 99, 0, (struct sockaddr *)dest, &addrlen);
 		if (num_bytes_received == 0) {
 			return NULL;
 		}
+		if (num_bytes_received < 0) {
+			throw errno;
+		}
 		/* Null-terminate the string */
 		*(buffer + num_bytes_received) = '\0';
 		return buffer;
@@ -111,7 +109,7 @@ char* Sock::recvAll() {
 			}
 
 			if (num_bytes_received < 0) {
-				throw errno * -1;
+				throw errno;
 			}
 			total_bytes_received += num_bytes_received;
 			has_been_read = true;
@@ -122,7 +120,8 @@ char* Sock::recvAll() {
 	return buffer;
 }
 
-/* Non-blocking recv call - Uses 'select' to poll for data from the FD. */
+/* Non-blocking recv call - Uses 'select' to poll for data from the FD. Returns an empty string if there
+is nothing to read. */
 char* Sock::recvAllNB() {
 	struct timeval tv;
 	fd_set readfs;
@@ -136,7 +135,7 @@ char* Sock::recvAllNB() {
 	if (FD_ISSET(this->sock_fd, &readfs)) {
 		return Sock::recvAll();
 	} else {
-		return NULL;
+		return (char *)"";
 	}
 }
 

todo.txt

@@ -1,10 +1,10 @@
-1. Try to make the ball go between screens.
-2. ----SHOULD BE DONE---- Add code to zip the dist/ folder inside the release_build script.
-3. Sign Windows executable, to remove 'Unknown Publisher' warnings.
-5. Create and publish statically-linked Linux binary, and create a build script for packaging it.
-6. Figure out how to build statically-linked Mac binary, and create a build script for packaging it.
-7. ----IN PROGRESS---- Figure out how to input game mode and (if applicable) IP address and port through the GUI, instead of the command-line.
-8. Clean up / refactor the raygui code in main.cpp, that asks user for game mode. Instead of just having a giant blob of code in main.cpp, maybe split it into a function, or move it to another file. It should be easy to split it into a different function, since none of the functions take any specific parameters. The text box function, for example, only takes in the rectangle coordinates, and the text to display. I can move the code to a function, and then pass in any parameters that I need to pass in (I don't think I need to pass many parameters, though).
-9. Allow the user to quit before the game actually starts i.e. while they are inputting the game mode.
-11. Add better error checking in check_server and check_client functions in check_input.cpp.
-12. Add 'install' target to Meson, to allow the user to install the game. This should also copy the .so files to the right locations.
+1. Sign Windows executable, to remove 'Unknown Publisher' warnings.
+2. Add 'install' target to Meson, to allow the user to install the game. This should also copy the .so files to the right locations.
+3. Use free() to free allocated memory.
+4. Use the struct to establish a connection, and to start each round (instead of sending strings).
+5. Figure out how to build statically-linked Mac binary, and create a build script for packaging it.
+6. Communicate the paddle reset position to the peer, after a round.
+7. Clean up / refactor the raygui code in main.cpp, that asks user for game mode. Instead of just having a giant blob of code in main.cpp, maybe split it into a function, or move it to another file. It should be easy to split it into a different function, since none of the functions take any specific parameters. The text box function, for example, only takes in the rectangle coordinates, and the text to display. I can move the code to a function, and then pass in any parameters that I need to pass in (I don't think I need to pass many parameters, though).
+8. Allow the user to specify which paddle they want to control, in multi-player mode.
+9. Try to make the ball go between screens.
+10. Change the networking code, so that a single server can connect two clients with each other. The server should provide player 1 with a code, and player 2 can connect with player 1 using that code (essentially like a room).