Sentry in progress

main.c

@@ -3,6 +3,17 @@
 #include <string.h>
 #include "server.h"
 
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <netdb.h>
+#include <sys/time.h>
+#include <math.h>
+#include <sys/select.h>
+#include <errno.h>
+
 int checkIpPortValid(int, char **);
 int valid_digit(char *);
 int checkIp(char *);
@@ -20,12 +31,27 @@ int main(int argc, char *argv[]) {
     while(1) { // The code will run until the "exit" command is summoned
         char buffer[100];
         // Show the user interface
-        printf("Available commands:\n\n new i - create a new ring with the i server only \n exit\n");
+        printf("Available commands:\n\n new i \n sentry i succi succi.IP succi.TCP \n exit\n");
         fgets(buffer, 100 , stdin);
         const char delim[2] = " ";
         if(strcmp(strtok(strdup(buffer), delim), "new") == 0) { // Check if the command is the new command
             sscanf(buffer, "%s %d", aux, &(myServer->key)); // Get the server key
             createServer(myServer);
+        } else  if(strcmp(strtok(strdup(buffer), delim), "sentry") == 0) { // Check if the command is the sentry command
+            sscanf(buffer, "%s %d %d %s %s", aux, &(myServer->key), &(myServer->nextKey), myServer->nextIp, myServer->nextPort); // Get the successor details
+            myServer->nextConnFD = connectToGivenServer(myServer); // Set the next server as the given server and establish a connection
+
+            int n = write(myServer->nextConnFD, "SUCCCONF\n", 10); // Tell the successor to define this server as its predecessor
+            if(n == -1)/*error*/exit(1);
+
+            n = read(myServer->nextConnFD, buffer, 128); // We already have all the data from the next server so we don't need to extract it here in the sentry
+            if(n==-1)/*error*/exit(1);
+
+            write(1,"echo: ",6); write(1,buffer,n);
+
+                // freeaddrinfo(res);
+            close(myServer->nextConnFD);
+
         } else if(strcmp(buffer, "exit\n") == 0) {
             exit(0);
         }

server.c

@@ -112,12 +112,49 @@ void createServer(Server* server) {
         } else {
           buffer[n] = '\0';
           write(1,"received: ",11); write(1,buffer,n); // Print incoming message
-          n = write(newfd,"Server Response\n",17);
-          if(n==-1)/*error*/exit(1);
+          if(strcmp(buffer, "SUCCCONF\n") == 0) { // If this server is set as a successor
+            if(server->prevConnFD == 0) { // If the previous server is not set
+              server->prevConnFD = newfd; // Set the incoming request as the previous server
+              sprintf(buffer, "SUCC %d %s %s\n", server->key, server->myIp, server->myPort);
+              n = write(server->prevConnFD,buffer, strlen(buffer)); // Server gives its predecessor his info
+              if(n==-1)/*error*/exit(1);
+            } else { // If it already has a predecessor
+
+              // This two operations that follow should only be done after the NEW command, which is where we no longer need to connect to the old predecessor
+              // // close(server->prevConnFD); // Close connection with predecessor
+              // // server->prevConnFD = newfd; // Set the incoming request as the previous server
+
+            }
+          }
+          // n = write(newfd,"Server Response\n",17);
+          // if(n==-1)/*error*/exit(1);
         }
       }
     }
   }
   freeaddrinfo(res); 
   close(fd);
 }
+
+int connectToGivenServer(Server* server) { // sentry 5 10 127.0.0.1 8005
+  fd = socket(AF_INET,SOCK_STREAM,0); //TCP socket
+  if (fd == -1) exit(1); //error
+
+  memset(&hints,0,sizeof hints);
+  hints.ai_family=AF_INET; //IPv4
+  hints.ai_socktype=SOCK_STREAM; //TCP socket
+
+  errcode = getaddrinfo(server->nextIp, server->nextPort,&hints,&res);
+  if(errcode != 0) {
+    printf("GET ADDRESS INFO ERROR\n");
+    exit(1);
+  }
+
+  n = connect(fd,res->ai_addr,res->ai_addrlen);
+  if(n == -1) {
+    printf("CONNECT ERROR\n");
+    exit(1);
+  }
+
+  return fd;
+}

server.h

@@ -6,13 +6,21 @@ typedef struct server {
   char myPort[10];
   int key;
 
-  char* nextIp;
-  char* previousIp;
-  char* doubleNextIp;
+  char nextIp[30];
+  char nextPort[10];
+  int nextKey;
+
+  char doubleNextIp[30];
+  char doubleNextPort[10];
+  int doubleNextKey;
+
+  int prevConnFD; // Holds the TCP connection to previous server
+  int nextConnFD; // Holds the TCP connection to next server
 }Server;
 
 
 void createServer(Server*);
+int connectToGivenServer(Server*);
 
 
 #endif

test/tester.c

@@ -37,7 +37,7 @@ void main(int argc, char *argv[]) {
     n=connect(fd,res->ai_addr,res->ai_addrlen);
     if(n==-1)/*error*/exit(1);
 
-    // while(1) {
+    while(1) {
         char user_input[128];
         fgets(user_input, 100 , stdin);
         n=write(fd,user_input, strlen(user_input));
@@ -47,7 +47,7 @@ void main(int argc, char *argv[]) {
         if(n==-1)/*error*/exit(1);
 
         write(1,"Teste: ",8); write(1,buffer,n); write(1, "\n", 3);
-    // }
+    }
 
     freeaddrinfo(res);
     close(fd);