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CarrCodes/agent.c

Last active December 8, 2017 23:38
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TCP Socket Server
Raw
agent.c
// This is the agent application that will be used to send actions to the server.
// It takes 3 arguments, server IP or host, port, and the action requested.
// List of includes
#include <netinet/in.h>
#include <netdb.h>
#include <arpa/inet.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <string.h>
#include <stdlib.h>
#include <errno.h>
#define MAXBUF 1024
#define MAXHOSTNAME 200
#define MAXACTION 10
#define MAXPORT 6
int main (int argc,char* argv[]) {
char cServer[MAXHOSTNAME];
char cPort[MAXPORT];
char cAction [MAXACTION];
int nPort;
if (argc < 4)
{
printf ("Usage: agent server_name server_port action_requested \r\n");
return(0);
}
memset(cServer,0,MAXHOSTNAME);
sprintf(cServer,"%s",argv[1]);
memset(cPort, 0, MAXPORT);
sprintf(cPort,"%s",argv[2]);
nPort = atoi(cPort);
memset(cAction,0,MAXACTION);
sprintf(cAction,"%s",argv[3]);
struct sockaddr_in name;
struct hostent *hent;
int sd;
// create a new socket to use for communication
if ((sd = socket (AF_INET, SOCK_STREAM, 0)) < 0) {
fprintf (stderr, "ERROR: socket() failed\n");
exit (-1);
}
fprintf(stdout,"Socket Created\n");
// Used to correctly fill in the server host
if ((hent = gethostbyname (cServer)) == NULL) {
fprintf (stderr, "ERROR: Host not found\n");
exit(-1);
}
else
bcopy (hent->h_addr, &name.sin_addr, hent->h_length);
name.sin_family = AF_INET;
name.sin_port = htons (nPort); // notice the host to network conversion.
// connect to the server
if (connect (sd, (struct sockaddr *)&name, sizeof(name)) < 0) {
fprintf (stderr, "ERROR: connect() failed\n");
printf("Connect error: %s", strerror(errno));
exit (-1);
}
printf("Connect OK\n");
// send the action to the server
int byteswritten = write (sd, cAction, strlen(cAction));
printf("wrote %d\n",byteswritten);
char buffer[MAXBUF];
int bytes_read = 0;
int total_bytes_read = 0;
do {
memset(buffer,0,MAXBUF);
bytes_read = read(sd, buffer, MAXBUF);
if (bytes_read < 0)
break;
fprintf(stdout,"Read %d bytes: [%s]\r\n", bytes_read,buffer);
total_bytes_read += bytes_read;
}
while ( bytes_read > 0 );
printf("Total Bytes Read = %d\r\n",total_bytes_read);
close(sd);
return 0;
}
Raw
server.c
//
// Name: Taylor Carr
// Date: December 3, 2017
// CS4310: Project #2
//
#include <time.h>
#include <netdb.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <stdbool.h>
#include <sys/time.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <sys/socket.h>
#define MAXBUF 1024
int main(int argc, const char * argv[]) {
// Initialize log.txt file
FILE *log,
*reader;
log = fopen("log.txt", "w+");
struct sockaddr_in my_addr;
socklen_t arrdLen = sizeof(my_addr);
short port = 0;
int SIZE = 10; // Max number of agents
char *agents[SIZE], // List of current connections
*times[SIZE]; // List of connection times
printf("Enter the port: ");
scanf("%hu", &port); // store port from user
// Set values for struct
memset(&my_addr, '\0', arrdLen); // set everything to 0
my_addr.sin_family = AF_INET;
my_addr.sin_port = htons(port);
my_addr.sin_addr.s_addr = INADDR_ANY;
memset(my_addr.sin_zero, '\0', sizeof(my_addr.sin_zero));
int sd;
// Create a new socket
if ((sd = socket (AF_INET, SOCK_STREAM, 0)) < 0) {
fprintf (stderr, "ERROR: socket() failed\n");
exit (-1);
}
printf("\nSocket created\n");
// Bind socket
if (bind (sd, (struct sockaddr *)&my_addr, arrdLen) < 0){
fprintf (stderr, "ERROR: bind() failed\n");
exit (-1);
}
printf("\nBind successful\n");
// Get listening IP and print it
char szHostName[255];
gethostname(szHostName, 255);
struct hostent *host_entry;
host_entry= gethostbyname(szHostName);
char * szLocalIP;
szLocalIP = inet_ntoa (*(struct in_addr *)*host_entry->h_addr_list);
printf("\nServer IP: %s\n", szLocalIP);
// Listen for connection
printf("\nListening for client\n");
if ((listen(sd, 1)) < 0){
fprintf (stderr, "ERROR: listen() failed\n");
exit (-1);
}
// Variable Declarations
char buffer[MAXBUF];
int bytes_read = 0;
int total_bytes_read = 0;
int found = 0, // Bool flag
i;
struct tm ts;
struct timeval connected[SIZE],
current,
difference;
time_t TIME;
// Initialize array to NULL
for(i = 0; i < SIZE; i++) {
agents[i] = NULL;
}
// Infinite Loop
while (true) {
// Client variables
struct sockaddr_in client;
int clientSocket;
socklen_t clientLength = sizeof(client);
memset(&client, 0, clientLength);
// Accept connection
clientSocket = accept(sd, (struct sockaddr *)&client, &clientLength);
// Read command from client
memset(buffer,0,MAXBUF);
bytes_read = read(clientSocket, buffer, MAXBUF);
if (bytes_read < 0)
break;
fprintf(stdout,"\nRead %d bytes: [%s]\r\n", bytes_read,buffer);
// Store client's IP in string
char *connectedIP = strdup(inet_ntoa(client.sin_addr));
// Option 1:
if ((strcmp(buffer, "#JOIN")) == 0) { // Join list of connected agents
found = 0;
// Get current time for log
TIME = time(NULL);
ts = *localtime(&TIME);
// Print message to log
char buf[80];
strftime(buf, sizeof(buf), "%a %Y-%m-%d %H:%M:%S %Z", &ts);
fprintf(log, "%s: Received a \"#JOIN\" action from agent \"%s\"", buf, connectedIP);
fprintf(log, "\n\n");
fflush(log);
// Handle #JOIN request appropriately
for (i = 0; i < SIZE; i++) {
if (agents[i] == NULL) {
}
else if (strcmp(agents[i], connectedIP) == 0){ // Agent found in list
found = 1;
// Write to agent
char response[] = "#ALREADY MEMBER";
write (clientSocket, response, strlen(response));
// Get time for log
TIME = time(NULL);
ts = *localtime(&TIME);
// Write to log
char buf[80];
strftime(buf, sizeof(buf), "%a %Y-%m-%d %H:%M:%S %Z", &ts);
fprintf(log, "%s: Responded to agent \"%s\" with \"#ALREADY MEMBER\"", buf, connectedIP);
fprintf(log, "\n\n");
fflush(log);
i = SIZE;
}
}
if (found == 0) { // Save IP to list/queue
for(i = 0; i < SIZE; i++) {
if (agents[i] == NULL) {
// Save IP to array
agents[i] = connectedIP;
// Save time to arrays
gettimeofday(&connected[i], NULL);
TIME = time(NULL);
times[i] = TIME;
ts = *localtime(&TIME);
// Write to log
char buf[80];
strftime(buf, sizeof(buf), "%a %Y-%m-%d %H:%M:%S %Z", &ts);
fprintf(log, "%s: Responded to agent \"%s\" with \"#OK\"", buf, connectedIP);
fprintf(log, "\n\n");
fflush(log);
// Write to agent
char response[] = "#OK";
write (clientSocket, response, strlen(response));
i = SIZE;
}
}
}
}
// Option 2: Leave list of connected agents
else if ((strcmp(buffer, "#LEAVE")) == 0) {
found = 0;
// Get time for log
TIME = time(NULL);
ts = *localtime(&TIME);
// Write to log
char buf[80];
strftime(buf, sizeof(buf), "%a %Y-%m-%d %H:%M:%S %Z", &ts);
fprintf(log, "%s: Received a \"#LEAVE\" action from agent \"%s\"", buf, connectedIP);
fprintf(log, "\n\n");
fflush(log);
// Handle #LEAVE request apprpriately
for (i = 0; i < SIZE; i++) {
if (agents[i] == NULL){
}
else if (!strcmp(agents[i], connectedIP)) { // Agent found in list
found = 1;
// Erase agent from arrays
agents[i] = NULL; // Replace IP with NULL
times[i] = NULL;
// Write to agent
char response[] = "#OK";
write (clientSocket, response, strlen(response));
// Get time for log
TIME = time(NULL);
ts = *localtime(&TIME);
// Write to log
char buf[80];
strftime(buf, sizeof(buf), "%a %Y-%m-%d %H:%M:%S %Z", &ts);
fprintf(log, "%s: Responded to agent \"%s\" with \"#OK\"", buf, connectedIP);
fprintf(log, "\n\n");
fflush(log);
}
}
if (found == 0) { // Agent not found in list
// Write to agent
char response[] = "#NOT MEMBER";
write (clientSocket, response, strlen(response));
// Write to log
char buf[80];
strftime(buf, sizeof(buf), "%a %Y-%m-%d %H:%M:%S %Z", &ts);
fprintf(log, "%s: Responded to agent \"%s\" with \"#NOT MEMBER\"", buf, connectedIP);
fprintf(log, "\n\n");
fflush(log);
}
}
// Option 3: Share list of connected agents
else if ((strcmp(buffer, "#LIST")) == 0) {
int index = -1;
found = 0;
// Get time for log
TIME = time(NULL);
ts = *localtime(&TIME);
// Write to log
char buf[80];
strftime(buf, sizeof(buf), "%a %Y-%m-%d %H:%M:%S %Z", &ts);
fprintf(log, "%s: Received a \"#LIST\" action from agent \"%s\"", buf, connectedIP);
fprintf(log, "\n\n");
fflush(log);
// See if requesting agent is currently in the list
for(i = 0; i < SIZE; i++) {
if (agents[i] == NULL){
}
else if(strcmp(agents[i], connectedIP) == 0) {
found = 1;
index = i;
i = SIZE; // Exit for loop
}
}
if (found == 1){ // Agent found in list
for(i = 0; i < SIZE; i++) {
if(agents[i] != NULL) { // ensure slot in list is taken by an agent
// Get the number of seconds that agent has been connected
gettimeofday(&current, NULL);
timersub(&current, &connected[i], &difference);
// Write to agent
char response[100];
sprintf(response, "<%s, %ld.%06ld>", agents[i], (long int)difference.tv_sec, (long int)difference.tv_usec);
write(clientSocket, response, strlen(response));
}
}
// Get time for log
TIME = time(NULL);
ts = *localtime(&TIME);
// Write to log
char buf[80];
strftime(buf, sizeof(buf), "%a %Y-%m-%d %H:%M:%S %Z", &ts);
fprintf(log, "%s: Responded to agent \"%s\" with current list", buf, connectedIP);
fprintf(log, "\n\n");
fflush(log);
}
else {
// Get time for log
TIME = time(NULL);
ts = *localtime(&TIME);
// Write to log
char buf[80];
strftime(buf, sizeof(buf), "%a %Y-%m-%d %H:%M:%S %Z", &ts);
fprintf(log, "%s: No response supplied to agent \"%s\"", buf, connectedIP);
fprintf(log, "\n\n");
fflush(log);
}
}
// Option 4: Send log.txt to agent
else if ((strcmp(buffer, "#LOG")) == 0) {
found = 0;
int index = -1;
// Get time for log
TIME = time(NULL);
ts = *localtime(&TIME);
// Write to log
char buf[80];
strftime(buf, sizeof(buf), "%a %Y-%m-%d %H:%M:%S %Z", &ts);
fprintf(log, "%s: Received a \"#LOG\" action from agent \"%s\"", buf, connectedIP);
fprintf(log, "\n\n");
fflush(log);
// See if requesting agent is currently in the list
for(i = 0; i < SIZE; i++) {
if (agents[i] == NULL){
}
else if(strcmp(agents[i], connectedIP) == 0) { // Agent found in list
found = 1;
index = i;
i = SIZE; // Exit for loop
}
}
if (found == 0) { // Agent not in list, ignore request
// Get time for log
TIME = time(NULL);
ts = *localtime(&TIME);
// Write to log
char buf[80];
strftime(buf, sizeof(buf), "%a %Y-%m-%d %H:%M:%S %Z", &ts);
fprintf(log, "%s: No response supplied to agent \"%s\"", buf, connectedIP);
fprintf(log, "\n\n");
fflush(log);
}
else {
// Read from log and write to agent
memset(buffer,0,MAXBUF);
reader = fopen("log.txt", "r");
if (reader == NULL) perror ("Error opening file");
else
{
while ( ! feof (reader) )
{
if ( fgets (buffer , MAXBUF , reader) == NULL ) break;
write(clientSocket, buffer, strlen(buffer));
}
fclose (reader);
}
// Get time for log
TIME = time(NULL);
ts = *localtime(&TIME);
// Write to log
char buf[80];
strftime(buf, sizeof(buf), "%a %Y-%m-%d %H:%M:%S %Z", &ts);
fprintf(log, "%s: Responded to agent \"%s\" with current log", buf, connectedIP);
fprintf(log, "\n\n");
fflush(log);
}
}
// Option 5: Invalid request from agent
else {
printf("ERROR: Invalid command from agent\n");
// Write to agent
char response[] = "#INVALID";
write (clientSocket, response, strlen(response));
// Get time for log
TIME = time(NULL);
ts = *localtime(&TIME);
// Write to log
char buf[80];
strftime(buf, sizeof(buf), "%a %Y-%m-%d %H:%M:%S %Z", &ts);
fprintf(log, "%s: Received an \"#INVALID\" action from agent \"%s\"", buf, connectedIP);
fprintf(log, "\n\n");
fflush(log);
}
// Close socket, flush log, close log
close(clientSocket);
memset(&client, 0, sizeof(client));
fflush(log);
}
return 0;
}
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