X-Git-Url: https://gapil.gnulinux.it/gitweb/?p=gapil.git;a=blobdiff_plain;f=sources%2FTCP_echod.c;h=333a5450b9df067e62444a8e36b646e112982e7c;hp=606f85281c81117797816563483880e32814f43f;hb=fa15a3f1ecd64efd8440e46d398fd9976abc3d25;hpb=d12bc3e1e4b3ee762036d1c226c3b2ba1a720fb9 diff --git a/sources/TCP_echod.c b/sources/TCP_echod.c index 606f852..333a545 100644 --- a/sources/TCP_echod.c +++ b/sources/TCP_echod.c @@ -1,6 +1,6 @@ -/* ElemEchoTCPServer.c +/* TCP_echod.c * - * Copyright (C) 2001 Simone Piccardi + * Copyright (C) 2001-2004 Simone Piccardi * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by @@ -26,26 +26,28 @@ * * Usage: echod -h give all info * - * $Id: TCP_echod.c,v 1.1 2003/05/02 09:50:55 piccardi Exp $ - * ****************************************************************/ /* * Include needed headers */ -#include /* predefined types */ -#include /* include unix standard library */ -#include /* IP addresses conversion utiliites */ -#include /* socket library */ -#include /* include standard I/O library */ -#include +#include /* primitive system data types */ +#include /* unix standard library */ +#include /* IP addresses conversion utilities */ +#include /* socket constants, types and functions */ +#include /* standard I/O library */ +#include /* date and time constants, types and functions */ #include /* syslog system functions */ -#include /* signal functions */ +#include /* signal constants, types and functions */ +#include /* error definitions and routines */ +#include /* C strings library */ +#include /* C standard library */ + #include "Gapil.h" #define BACKLOG 10 #define MAXLINE 256 -int demonize = 1; /* daemon use option */ -int debugging = 0; /* debug info printing option */ +int demonize = 1; /* daemon use option: default is daemon */ +int debugging = 0; /* debug info printing option: default is no debug */ /* Subroutines declaration */ void usage(void); void ServEcho(int sockfd); @@ -57,15 +59,21 @@ int main(int argc, char *argv[]) * Variables definition */ int list_fd, conn_fd; + int waiting = 0; + int keepalive = 0; + int reuse = 0; + int compat = 0; pid_t pid; - struct sockaddr_in serv_add; + struct sockaddr_in cli_add; + socklen_t len; + char debug[MAXLINE], ipaddr[20]; /* * Input section: decode parameters passed in the calling * Use getopt function */ int i; opterr = 0; /* don't want writing to stderr */ - while ( (i = getopt(argc, argv, "hdi")) != -1) { + while ( (i = getopt(argc, argv, "hkrdicw:")) != -1) { switch (i) { /* * Handling options @@ -78,9 +86,21 @@ int main(int argc, char *argv[]) case 'i': demonize = 0; break; + case 'k': + keepalive = 1; + break; + case 'r': + reuse = 1; + break; + case 'c': + compat = 1; + break; case 'd': debugging = 1; break; + case 'w': + waiting = strtol(optarg, NULL, 10); + break; case '?': /* unrecognized options */ printf("Unrecognized options -%c\n",optopt); usage(); @@ -95,23 +115,17 @@ int main(int argc, char *argv[]) * Main code beginning * * ***********************************************************/ - /* install SIGCHLD handler */ - Signal(SIGCHLD, HandSigCHLD); /* establish handler */ - /* create socket */ - if ( (list_fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) { - perror("Socket creation error"); - exit(1); - } - /* initialize address */ - 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 */ - /* bind socket */ - if (bind(list_fd, (struct sockaddr *)&serv_add, sizeof(serv_add)) < 0) { - perror("bind error"); - exit(1); + /* Main code begin here */ + if (compat) { /* install signal handler */ + Signal(SIGCHLD, HandSigCHLD); /* non restarting handler */ + } else { + SignalRestart(SIGCHLD, HandSigCHLD); /* restarting handler */ } + /* create and bind socket */ + if ( (list_fd = sockbindopt(argv[optind], "echo", 6, + SOCK_STREAM, reuse)) < 0) { + return 1; + } /* release privileges and go daemon */ if (setgid(65534) !=0) { /* first give away group privileges */ perror("cannot give away group privileges"); @@ -133,13 +147,26 @@ int main(int argc, char *argv[]) PrintErr("listen error"); exit(1); } + if (waiting) sleep(waiting); /* handle echo to client */ while (1) { /* accept connection */ - if ( (conn_fd = accept(list_fd, NULL, NULL)) < 0) { + len = sizeof(cli_add); + while (((conn_fd = accept(list_fd, (struct sockaddr *)&cli_add, &len)) + < 0) && (errno == EINTR)); + if (conn_fd < 0) { PrintErr("accept error"); exit(1); } + if (debugging) { + inet_ntop(AF_INET, &cli_add.sin_addr, ipaddr, sizeof(ipaddr)); + snprintf(debug, MAXLINE, "Accepted connection form %s\n", ipaddr); + if (demonize) { + syslog(LOG_DEBUG, debug); + } else { + printf("%s", debug); + } + } /* fork to handle connection */ if ( (pid = fork()) < 0 ){ PrintErr("fork error"); @@ -147,7 +174,19 @@ int main(int argc, char *argv[]) } if (pid == 0) { /* child */ close(list_fd); /* close listening socket */ + if (keepalive) { /* enable keepalive ? */ + setsockopt(conn_fd, SOL_SOCKET, SO_KEEPALIVE, + &keepalive, sizeof(keepalive)); + } ServEcho(conn_fd); /* handle echo */ + if (debugging) { + snprintf(debug, MAXLINE, "Closed connection %s\n", ipaddr); + if (demonize) { + syslog(LOG_DEBUG, debug); + } else { + printf("%s", debug); + } + } exit(0); } else { /* parent */ close(conn_fd); /* close connected socket */ @@ -164,8 +203,12 @@ void usage(void) { printf("Usage:\n"); printf(" echod [-h] \n"); printf(" -h print this help\n"); - printf(" -d print debug info\n"); + printf(" -d write debug info\n"); + printf(" -k enable SO_KEEPALIVE\n"); + printf(" -r enable SO_REUSEADDR\n"); printf(" -i use interactively\n"); + printf(" -c disable BSD semantics\n"); + printf(" -w N wait N sec. before calling accept\n"); exit(1); } /* @@ -175,14 +218,21 @@ void ServEcho(int sockfd) { char buffer[MAXLINE]; int nread, nwrite; char debug[MAXLINE+20]; - int size; /* main loop, reading 0 char means client close connection */ while ( (nread = read(sockfd, buffer, MAXLINE)) != 0) { + if (nread < 0) { + PrintErr("Errore in lettura"); + return; + } nwrite = FullWrite(sockfd, buffer, nread); + if (nwrite) { + PrintErr("Errore in scrittura"); + return; + } if (debugging) { buffer[nread] = 0; snprintf(debug, MAXLINE+20, "Letti %d byte, %s", nread, buffer); - if (demonize) { /* go daemon */ + if (demonize) { /* daemon mode */ syslog(LOG_DEBUG, debug); } else { printf("%s", debug); @@ -195,8 +245,8 @@ void ServEcho(int sockfd) { * routine to print error on stout or syslog */ void PrintErr(char * error) { - if (demonize) { /* go daemon */ - syslog(LOG_ERR, error); + if (demonize) { /* daemon mode */ + syslog(LOG_ERR, "%s: %m", error); /* log string and error message */ } else { perror(error); }