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/*
* Copyright (c) 1999-2003 Smithsonian Astrophysical Observatory
*/
#include <xpap.h>
/*
*----------------------------------------------------------------------------
*
*
* Private Routines and Data
*
*
*----------------------------------------------------------------------------
*/
#if HAVE_MINGW32==0
static int alarm_flag=0;
#ifdef ANSI_FUNC
static void AlarmFunc (int signo)
#else
static void AlarmFunc (signo)
int signo;
#endif
{
alarm_flag = 1;
}
/*
*----------------------------------------------------------------------------
*
*
* Public Routines and Data
*
*
*----------------------------------------------------------------------------
*/
/*
*----------------------------------------------------------------------------
*
* Routine: alrmconnect
*
* Purpose: connect with alarm-based timeout
*
* Returns: status
*
* adapted from the connect_alarm() code in:
* W. Richard Stevens
* "Advanced Programming in the Unix Environment"
* Addison-Wesley Publishing Co, 1992
* p. 350
*
*----------------------------------------------------------------------------
*/
#ifdef ANSI_FUNC
int alrmconnect(int sockfd, void *saptr, int salen, int nsec)
#else
int alrmconnect(sockfd, saptr, salen, nsec)
int sockfd;
void *saptr;
int salen;
int nsec;
#endif
{
int status=0;
struct sigaction act1, oact1;
/* no error yet */
alarm_flag = 0;
errno = 0;
/* set up alarm */
if( nsec ){
act1.sa_handler = AlarmFunc;
sigemptyset(&act1.sa_mask);
act1.sa_flags = 0;
#ifdef SA_INTERRUPT
act1.sa_flags |= SA_INTERRUPT;
#endif
if( sigaction(SIGALRM, &act1, &oact1) < 0 ){
goto done;
}
/* start alarm */
alarm(nsec);
}
/* try to connect */
status=connect(sockfd, (struct sockaddr *)saptr, salen);
/* turn off alarm if it did not go off */
if( nsec )
alarm(0);
done:
/* check for alarm => we timed out */
if( alarm_flag ){
xclose(sockfd);
errno = ETIMEDOUT;
status = -1;
}
return(status);
}
#endif
/*
*----------------------------------------------------------------------------
*
* Routine: noblkconnect
*
* Purpose: non-blocking connect with select-based timeout
*
* Returns: status
*
* adapted from the connect_nonb() code in:
* W. Richard Stevens
* "Advanced Programming in the Unix Environment"
* Addison-Wesley Publishing Co, 1992
* p. 411
*
*----------------------------------------------------------------------------
*/
#ifdef ANSI_FUNC
int noblkconnect(int sockfd, void *saptr, int salen, int nsec)
#else
int noblkconnect(sockfd, saptr, salen, nsec)
int sockfd;
void *saptr;
int salen;
int nsec;
#endif
{
int flags, n, error;
socklen_t len;
fd_set rset, wset;
struct timeval tval;
/* save state and set in non-blocking mode */
xfcntl_nonblock(sockfd, flags);
error = 0;
if( (n = connect(sockfd, (struct sockaddr *) saptr, salen)) < 0){
if((xerrno != EINPROGRESS) && (xerrno != EWOULDBLOCK))
return(-1);
}
/* Do whatever we want while the connect is taking place. */
if(n == 0)
goto done; /* connect completed immediately */
FD_ZERO(&rset);
FD_SET(sockfd, &rset);
wset = rset;
tval.tv_sec = nsec;
tval.tv_usec = 0;
if( (n = xselect(sockfd+1, &rset, &wset, NULL,
nsec ? &tval : NULL)) == 0) {
xclose(sockfd); /* timeout */
errno = ETIMEDOUT;
return(-1);
}
if(FD_ISSET(sockfd, &rset) || FD_ISSET(sockfd, &wset)) {
len = sizeof(error);
if(getsockopt(sockfd, SOL_SOCKET, SO_ERROR, (void *)&error, &len) <0)
return(-1); /* Solaris pending error */
} else{
errno = ETIMEDOUT;
}
done:
xfcntl_restore(sockfd, flags); /* restore file status flags */
if(error) {
xclose(sockfd); /* just in case */
errno = error;
return(-1);
}
return(0);
}
#ifdef DO_MAIN
/*
* solaris: gcc -o atest atest.c -lsocket -lnsl
* linux: gcc -o atest atest.c
* os x: gcc -o atest atest.c
*/
#include <stdio.h>
extern char *optarg;
extern int optind;
int main(int argc, char **argv)
{
int c;
int args;
int status;
int fd;
int doalarm=0;
int nsec=2;
unsigned int ip;
char *sip;
struct sockaddr_in sock_in;
/* process switch arguments */
while ((c = getopt(argc, argv, "ab")) != -1){
switch(c){
case 'a':
doalarm = 1;
break;
case 'b':
doalarm = 0;
break;
}
}
args = argc - optind;
if( args > 0 )
sip = argv[optind];
/* this ip is bogus and normally will cause connect to hang */
else
sip ="209.1.1.1";
/* set up socket to a bogus ip and port */
if( (int)(ip = inet_addr(sip)) == -1 ){
perror("inet_addr");
exit(1);
}
if( (fd = xsocket(AF_INET, SOCK_STREAM, 0)) < 0 ){
perror("socket");
exit(1);
}
memset((char *)&sock_in, 0, sizeof(sock_in));
sock_in.sin_family = AF_INET;
sock_in.sin_addr.s_addr = ip;
sock_in.sin_port = htons(80);
if( doalarm ){
fprintf(stderr, "alarm-based connect() ...\n");
status=alrmconnect(fd, (void *)&sock_in, sizeof(sock_in), nsec);
}
else{
fprintf(stderr, "non-blocking connect() ...\n");
status=noblkconnect(fd, (void *)&sock_in, sizeof(sock_in), nsec);
}
/* if alarm_flag is 1, alarm went off and interrupted connect */
fprintf(stderr, "alarm_flag=%d status=%d\n", alarm_flag, status);
if( status != 0 )
perror("connect");
}
#endif
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