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/*
* Copyright (c) 1989 Regents of the University of California.
* All rights reserved. The Berkeley software License Agreement
* specifies the terms and conditions for redistribution.
*/
#include <popper.h>
RCSID("$Id: popper.c,v 1.16 2002/07/04 14:09:25 joda Exp $");
int hangup = FALSE ;
static RETSIGTYPE
catchSIGHUP(int sig)
{
hangup = TRUE ;
/* This should not be a problem on BSD systems */
signal(SIGHUP, catchSIGHUP);
signal(SIGPIPE, catchSIGHUP);
SIGRETURN(0);
}
int pop_timeout = POP_TIMEOUT;
jmp_buf env;
static RETSIGTYPE
ring(int sig)
{
longjmp(env,1);
}
/*
* fgets, but with a timeout
*/
static char *
tgets(char *str, int size, FILE *fp, int timeout)
{
signal(SIGALRM, ring);
alarm(timeout);
if (setjmp(env))
str = NULL;
else
str = fgets(str,size,fp);
alarm(0);
signal(SIGALRM,SIG_DFL);
return(str);
}
/*
* popper: Handle a Post Office Protocol version 3 session
*/
int
main (int argc, char **argv)
{
POP p;
state_table * s;
char message[MAXLINELEN];
signal(SIGHUP, catchSIGHUP);
signal(SIGPIPE, catchSIGHUP);
/* Start things rolling */
pop_init(&p,argc,argv);
/* Tell the user that we are listenting */
pop_msg(&p,POP_SUCCESS, "POP3 server ready");
/* State loop. The POP server is always in a particular state in
which a specific suite of commands can be executed. The following
loop reads a line from the client, gets the command, and processes
it in the current context (if allowed) or rejects it. This continues
until the client quits or an error occurs. */
for (p.CurrentState=auth1;p.CurrentState!=halt&&p.CurrentState!=error;) {
if (hangup) {
pop_msg(&p, POP_FAILURE, "POP hangup: %s", p.myhost);
if (p.CurrentState > auth2 && !pop_updt(&p))
pop_msg(&p, POP_FAILURE,
"POP mailbox update failed: %s", p.myhost);
p.CurrentState = error;
} else if (tgets(message, MAXLINELEN, p.input, pop_timeout) == NULL) {
pop_msg(&p, POP_FAILURE, "POP timeout: %s", p.myhost);
if (p.CurrentState > auth2 && !pop_updt(&p))
pop_msg(&p,POP_FAILURE,
"POP mailbox update failed: %s", p.myhost);
p.CurrentState = error;
}
else {
/* Search for the command in the command/state table */
if ((s = pop_get_command(&p,message)) == NULL) continue;
/* Call the function associated with this command in
the current state */
if (s->function) p.CurrentState = s->result[(*s->function)(&p)];
/* Otherwise assume NOOP and send an OK message to the client */
else {
p.CurrentState = s->success_state;
pop_msg(&p,POP_SUCCESS,NULL);
}
}
}
/* Say goodbye to the client */
pop_msg(&p,POP_SUCCESS,"Pop server at %s signing off.",p.myhost);
/* Log the end of activity */
pop_log(&p,POP_PRIORITY,
"(v%s) Ending request from \"%s\" at %s\n",VERSION,p.client,p.ipaddr);
/* Stop logging */
closelog();
return(0);
}
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