Final Project: Battle-Server

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Team: Jesse Nhan & Ronald Washington III

Due: May 14, 2018

CS 375: Computer Networks

For this project, we are developing our own implementation of a multi-player network game, Battle-Server. Within this game four clients are joining a simulation where they are communicating their tactics to defeat a monster (Boss) and must use a limited set of moves during the battle. This network game utilizes multiple I_O, processes concurrency to relative addresses, and take in input.

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Server.c

Program Structure and Design

• typedef struct Monster{char Name; int HP; int PATK;}**

  This definition enables us to be able to identify and later use Monster stats.

• typedef struct Client{char Name; int HP; int PATK; int fd; int DEF;}*

  This definition enables us to be able to identify and later use Client stats.

• Monster MonsterGen(Monster M, int i, int j, int fdmax, int listener, fd_set master)

  The purpose of this function is to initialize the creation of a Monster. Within here the attributes associated with the Monster stats are created and is later prepared to sending data for use in battle.

• void acceptance(int i)

  This helper function allows the game to recognize when all players have been acknowledged in the simulation as well as transfers the data sent in the chat room.

• Client PlayerGen(Client P, int i, int j, int fdmax, int listener, fd_set master)

  The purpose of this function is to initialize the creation of a Player. Within here the attributes associated with the Monster stats are created and is later prepared to sending data for use in battle.

• *Client Player_stats(Queue history, Client Player, Monster M)

  This helper function aides the clients in battle by recognizing standard input for defending monster attack and self healing.

• void End_Game(Monster M, Client Player, int j, int fdmax, int listener, fd_set master)

  The purpose of this function is to recognize whether the player/client has 'won' or 'lost' the game and send a message as such notice.

• **void get_in_addr(struct sockaddr sa)

  The purpose of this function is to gather the addresses of the clients.

• int main(void)

  Here is where we implement the usage of Select to perform the actions of the clients and servers for multiple Inputs and Outputs. Select typically utilizes a list of file descriptions to recognize who and what it is performing actions for whether it be the number of clients or for the server itself. Once the server and the amount of connections has been established, the program then beings to accept up to four clients. when has clients have been recognized then the battle simulation commences where the monster and player generators are initialized. A queue is used to track the input of options that the clients/players choose, and Select then recognizes these inputs to determine who chose what behavior and enact it upon the monster within the server. Once the Select has discovered the action chosen by each client then the action is then broadcasted to all clients. The server is influenced by the choices and the remaining clients are simply notified. Additionally, a chat system has been developed so that between choosing their battle options, clients are able to communicate before facing the enemy. Once a choice has been chosen, that client will not be able to type or chat anymore until all four are done choosing but the client can still listen to other clients.

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Client.c

Program Structure and Design

• **void get_in_addr(struct sockaddr sa)

  The purpose of this function is to gather the address of the server.

• int main(void)

  Here we are essentially opening our connectoin and gathering the clients who are apart of the game. The client simply uses Select by utilizing the standard in and and the information that it gathers from the server. Based on these two sources we are able to determine when there is an acception to the connection and then allow for commands such as Attack, Defend, and Heal to be collected to then be sent to the server program.

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Implementation Challenges

• We struggled with ensuring all the bits were being transfered between clients.
• Had issues with implementing the queue to recognize and save the different choices made by individual clients.
• Had issues with implementing the healing and defending options for clients due to the order of their input countering the other's health for said client.
• Had issues with implementing functions for the bases of the main function due to our initial version of the project being done altogether.
• We also struggled with how the server was sending messages to the clients. Only a few of the clients would get the message while others would get nothing.

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Testing

• Consecutively damage from Monster to reach end game (Lose)
• Consistently attacking Monster to read end game (Win)
• Checking against the properties of heal and defend to work differently
• Ensuring chat works by putting input from each client one by one and making sure each person receives all comments from other clients.
• Ensuring protocols worked correctly from the server to the client.

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Remaining Bugs

• The are still some possible memory leaks within our program. We tried to suppress all errors down to a minimum.
• It is possible that if an alien had inhuman speed to put two inputs at the same time, it may crash our game.
• After closing the server or the game, the ending messages would repeat.

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