Modifiche al server di echo per introdurre le stampe di debugging e la

[gapil.git] / listati / TCP_echod.c

diff --git a/listati/TCP_echod.c b/listati/TCP_echod.c
new file mode 100644 (file)
index 0000000..81085a7
--- /dev/null
+++ b/listati/TCP_echod.c
@@ -0,0 +1,60 @@
+int main(int argc, char *argv[])
+{
+    int list_fd, conn_fd; 
+    pid_t pid;
+    struct sockaddr_in serv_add;
+    ...
+    /* create socket */
+    if ( (list_fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
+       perror("Socket creation error");
+       exit(1);
+    }
+    /* initialize address and bind socket */
+    memset((void *)&serv_add, 0, sizeof(serv_add)); /* clear server address */
+    serv_add.sin_family = AF_INET;                  /* address type is INET */
+    serv_add.sin_port = htons(7);                   /* echo port is 7 */
+    serv_add.sin_addr.s_addr = htonl(INADDR_ANY);   /* connect from anywhere */
+    if (bind(list_fd, (struct sockaddr *)&serv_add, sizeof(serv_add)) < 0) {
+       perror("bind error");
+       exit(1);
+    }
+    /* give away privileges and go daemon */
+    if (setgid(65534) !=0) { /* first give away group privileges */
+       perror("cannot give away group privileges");
+       exit(1);
+    }
+    if (setuid(65534) !=0) { /* and only after user ... */
+       perror("cannot give away user privileges");
+       exit(1);
+    }
+    if (demonize) {          /* go daemon */
+        openlog(argv[0], 0, LOG_DAEMON); /* open logging */
+       if (daemon(0, 0) != 0) {
+           perror("cannot start as daemon");
+           exit(1);
+       }
+    }
+    /* main body */
+    if (listen(list_fd, BACKLOG) < 0 ) { /* listen on socket */
+       PrintErr("listen error");
+       exit(1);
+    }
+    while (1) {                          /* handle echo to client */
+       if ( (conn_fd = accept(list_fd, NULL, NULL)) < 0) { 
+           PrintErr("accept error");
+           exit(1);
+       }
+       if ( (pid = fork()) < 0 ) {      /* fork to handle connection */
+           PrintErr("fork error");
+           exit(1);
+       }
+       if (pid == 0) {      /* child */
+           close(list_fd);          /* close listening socket */   
+           ServEcho(conn_fd);       /* handle echo */
+           exit(0);
+       } else {             /* parent */
+           close(conn_fd);          /* close connected socket */
+       }
+    }
+    exit(0);     /* normal exit, never reached */
+}