include fixes

[unix-history] / usr / src / libexec / comsat / comsat.c

#ifndef lint
static  char *sccsid = "@(#)comsat.c    4.8 83/07/01";
#endif

#include <sys/types.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/wait.h>

#include <netinet/in.h>

#include <stdio.h>
#include <sgtty.h>
#include <utmp.h>
#include <signal.h>
#include <errno.h>
#include <netdb.h>

/*
* comsat
*/
int     debug = 0;
#define dprintf if (debug) printf

#define MAXUTMP 100             /* down from init */

struct  sockaddr_in sin = { AF_INET };
extern  errno;

struct  utmp utmp[100];
int     nutmp;
int     uf;
unsigned utmpmtime;                     /* last modification time for utmp */
int     onalrm();
struct  servent *sp;

#define NAMLEN (sizeof (uts[0].ut_name) + 1)

main(argc, argv)
char **argv;
{
       register cc;
       char buf[BUFSIZ];
       int s;

       sp = getservbyname("biff", "udp");
       if (sp == 0) {
               fprintf(stderr, "comsat: biff/udp: unknown service\n");
               exit(1);
       }
       if (!debug)
       if (fork())
               exit();
       chdir("/usr/spool/mail");
       if((uf = open("/etc/utmp",0)) < 0)
               perror("/etc/utmp"), exit(1);
       if (!debug)
       while (fork())
               wait(0);
       sleep(10);
       onalrm();
       signal(SIGALRM, onalrm);
       signal(SIGTTOU, SIG_IGN);
       s = socket(AF_INET, SOCK_DGRAM, 0, 0);
       if (s < 0) {
               perror("socket");
               exit(1);
       }
       sin.sin_port = sp->s_port;
       if (bind(s, &sin, sizeof (sin), 0) < 0) {
               perror("bind");
               exit(1);
       }
       for (;;) {
               char msgbuf[100];
               int cc;

               cc = recv(s, msgbuf, sizeof (msgbuf) - 1, 0);
               if (cc <= 0) {
                       if (errno != EINTR)
                               sleep(1);
                       errno = 0;
                       continue;
               }
               msgbuf[cc] = 0;
               mailfor(msgbuf);
       }
}

onalrm()
{
       struct stat statbf;
       struct utmp *utp;

       dprintf("alarm\n");
       alarm(15);
       fstat(uf,&statbf);
       if (statbf.st_mtime > utmpmtime) {
               dprintf(" changed\n");
               utmpmtime = statbf.st_mtime;
               lseek(uf, 0, 0);
               nutmp = read(uf,utmp,sizeof(utmp))/sizeof(struct utmp);
       } else
               dprintf(" ok\n");
}

mailfor(name)
       char *name;
{
       register struct utmp *utp = &utmp[nutmp];
       register char *cp;
       char *rindex();
       int offset;

       dprintf("mailfor %s\n", name);
       cp = name;
       while (*cp && *cp != '@')
               cp++;
       if (*cp == 0) {
               dprintf("bad format\n");
               return;
       }
       *cp = 0;
       offset = atoi(cp+1);
       while (--utp >= utmp)
               if (!strncmp(utp->ut_name, name, sizeof(utmp[0].ut_name)))
                       if (fork() == 0) {
                               signal(SIGALRM, SIG_DFL);
                               alarm(30);
                               notify(utp, offset), exit(0);
                       } else
                               while (wait3(0, WNOHANG, 0) > 0)
                                       continue;
}

char *cr;

notify(utp, offset)
       register struct utmp *utp;
{
       FILE *tp;
       struct sgttyb gttybuf;
       char tty[20], hostname[32];
       char name[sizeof (utmp[0].ut_name) + 1];
       struct stat stb;

       strcpy(tty, "/dev/");
       strncat(tty, utp->ut_line, sizeof(utp->ut_line));
       dprintf("notify %s on %s\n", utp->ut_name, tty);
       if (stat(tty, &stb) == 0 && (stb.st_mode & 0100) == 0) {
               dprintf("wrong mode\n");
               return;
       }
       if ((tp = fopen(tty,"w")) == 0) {
               dprintf("fopen failed\n");
               return;
       }
       ioctl(fileno(tp), TIOCGETP, &gttybuf);
       cr = (gttybuf.sg_flags & CRMOD) ? "" : "\r";
       gethostname(hostname, sizeof (hostname));
       strncpy(name, utp->ut_name, sizeof (utp->ut_name));
       name[sizeof (name) - 1] = 0;
       fprintf(tp,"%s\n\007New mail for %s@%s\007 has arrived:%s\n",
           cr, name, hostname, cr);
       fprintf(tp,"----%s\n", cr);
       jkfprintf(tp, name, offset);
       fclose(tp);
}

jkfprintf(tp, name, offset)
       register FILE *tp;
{
       register FILE *fi;
       register int linecnt, charcnt;
       char line[BUFSIZ];

       dprintf("HERE %s's mail starting at %d\n",
           name, offset);
       if ((fi = fopen(name,"r")) == NULL) {
               dprintf("Cant read the mail\n");
               return;
       }
       fseek(fi, offset, 0);
       /* 
        * Print the first 7 lines or 560 characters of the new mail
        * (whichever comes first).  Skip header crap other than
        * From: and Subject:.
        */
       linecnt = 7;
       charcnt = 560;
       while (fgets(line, sizeof (line), fi) != NULL) {
               register char *cp;
               char *index();

               if (linecnt <= 0 || charcnt <= 0) {  
                       fprintf(tp,"...more...%s\n", cr);
                       return;
               }
               cp = index(line, ':');
               if (cp &&
                   strncmp(line, "Date", cp - line) &&
                   strncmp(line, "From", cp - line) &&
                   strncmp(line, "Subject", cp - line) &&
                   strncmp(line, "To", cp - line))
                       continue;
               cp = index(line, '\n');
               if (cp)
                       *cp = '\0';
               fprintf(tp,"%s%s\n", line, cr);
               linecnt--, charcnt -= strlen(line);
       }
       fprintf(tp,"----%s\n", cr);
}