Nice work on the socket code!!

[Bradley Smith]

In article <1498 at shade.UUCP>, steveb at shade.UUCP (Steve Barber) writes:
> The symptoms are as follows:  the driver program gets started up in
> the background.  It creates a socket, binds it to a filename in /tmp,
> then does a listen(s, 5) on it.  The client program (one per player)
> then creates a socket, binds it to the filename, and does a connect(2)
> call to connect to it.  It hangs about here someplace until an alarm
> goes off.
> 
> The select(2) call that the driver runs is not detecting the connection
> requested by the client program, therefore it never calls accept(2).
> According to a man page I checked on a BSD system (accept(2), specifically),
> select is supposed to set a flag in the read bitmask if there is a
> connection pending.  Currently it doesn't look like this functionality
> is provided in the 1.2 version of select.
Here is tcpsend.c and tcpread.c.  Make sure that you have some windows
around via windy -b ksh, then.  Start tcpread in 1 window then go to the
next window, and starting up tcpsend, and in another window start
tcpsend again.  tcpread should see the new connects, if not you
don't have the most recent release of software in which I can mail it.
-- 
Bradley Smith
Telecommunications Solutions Development
AT&T Bell Labs, Holmdel, NJ 
201-949-0090 att!holin!bes or bes at holin.ATT.COM
==============cut here============
: This is a shar archive.  Extract with sh, not csh.
: This archive ends with exit, so do not worry about trailing junk.
echo 'Extracting tcpread.c'
sed 's/^X//' > tcpread.c << '+ END-OF-FILE tcpread.c'
X#include	<stdio.h>
X#include	<sys/types.h>
X#include	<uipc/socket.h>
X#include	<uipc/un.h>
X
Xchar	*PORT;
X#define TESTSIZE 512
X
Xchar sourcebuf[TESTSIZE];
Xchar sinkbuf[TESTSIZE];
X
Xextern int errno;
Xstruct sockaddr_un sinsource;
Xstruct sockaddr_un sinsink;
Xint s, s1, ns[100], nscnt = 0;
X
Xlong t;
Xextern char *ctime();
X
Xlong timeout=0;
X
X
Xmain(argc,argv)
Xint argc;
Xchar *argv[];
X{
X	if(argc != 2) {
X		fprintf(stderr,"usage: %s port_name\n", argv[0]);
X		exit(-1);
X	}
X	PORT = argv[1];
X	/* tcploopinit(); */
X	tcpsource();
X	tcpsink();
X}
Xtcpsource()
X{
X	int i, cc;
X	struct hostent *hp;
X	sinsource.sun_family = AF_UNIX;
X	sinsink.sun_family = AF_UNIX;
X
X	for(i = 0; i< TESTSIZE;i++) {
X		sinkbuf[i] = 0;
X		sourcebuf[i] = i;
X	}
X	s1 = socket(AF_UNIX, SOCK_STREAM, 0);
X	if( s1 == -1) {
X		perror("Second socket() failed!");
X		exit(1);
X	}
X	strcpy(sinsource.sun_path,PORT);
X	strcpy(sinsink.sun_path,PORT);
X
X
X	if(bind(s1, &sinsink, sizeof(struct sockaddr_un)) == -1) {
X		perror("Frist bind failed!");
X		exit(1);
X	}
X
X	if(listen(s1, 5) == -1) {
X		perror("Listen failed!\n");
X		exit(1);
X	}
X
X}
Xtcpsink()
X{
X	int i, j;
X	int hismsglen;
X	static int addrlen = 0;
X	int sret, srd, swr, sex;
X	long t;
X	int a2, ret;
X	char xxx[16];
X
X
Xhere:
X
X	do {
X		a2 = 1 << s1;	 /* get first one */
X		for(i=0;i<nscnt;i++) 
X			if(ns[i])
X				a2 |= 1 << ns[i];
X		time(&t);
X		printf("select bitmask = 0x%x @ %s",a2, ctime(&t));
X		t = 3;
X		ret = select(32,&a2,0,0,&timeout);
X		time(&t);
X		printf("select ret=%d, bitmask = 0x%x, - %s", ret, a2,ctime(&t));
X	} while(ret == 0);
X	if( (1 << s1) & a2) {
X		for(j = 0; j<nscnt;j++) {
X			if(!ns[j])
X				break;
X		}
X		if(j == nscnt) {
X			ns[nscnt] = accept(s1, (char *) &sinsink, &addrlen);
X			printf("new connection nscnt = %d\n",nscnt);
X			nscnt++;
X		}else {
X			ns[j] = accept(s1, (char *) &sinsink, &addrlen);
X			printf("new connection j = %d\n",j);
X		}
X	}
X	for(i=0;i<nscnt;i++) {
X	    if( (1 << ns[i]) & a2) {
X		printf("ns[%d]:", i); fflush(stdout);
X		hismsglen = read(ns[i], sinkbuf, TESTSIZE);
X		if(hismsglen > 0) {
X			printf("tcpsink: %d characters where received\n"
X				,hismsglen);
X		}else {
X			sret = errno;
X			perror("Recv failed!");
X			printf("errno = %d\n", sret);
X			close(ns[i]);
X			ns[i] = 0;
X		}
X	   }
X	}
X	printf("hit return\n");
X	gets(xxx);
X	goto here;
Xthere:
X	if(close(s1) == -1)
X		perror("Close on s1 failed!");
X	if(close(ns) == -1)
X		perror("Close on ns failed!");
X	exit(0);
X}
X
+ END-OF-FILE tcpread.c
chmod 'u=rw,g=r,o=r' 'tcpread.c'
echo '	-rw-r--r--   1 bes      HSJ         2378 Oct 11 20:45 tcpread.c        (as sent)'
echo '	\c'
/bin/ls -l tcpread.c
echo 'Extracting tcpsend.c'
sed 's/^X//' > tcpsend.c << '+ END-OF-FILE tcpsend.c'
X#include	<stdio.h>
X#include	<signal.h>
X#include	<sys/types.h>
X#include	<uipc/socket.h>
X#include	<uipc/un.h>
X
Xchar *PORT;
X#define TESTSIZE 512
X
Xchar sourcebuf[TESTSIZE];
Xchar sinkbuf[TESTSIZE];
X
Xextern int errno;
Xstruct sockaddr_un sinsource;
Xstruct sockaddr_un sinsink;
Xint s, s1, ns;
Xint endit();
Xint timeout=2;
X
Xmain(argc,argv)
Xint argc;
Xchar *argv[];
X{
X	if(argc != 2) {
X		fprintf(stderr,"usage: %s port_name\n", argv[0]);
X		exit(-1);
X	}
X	PORT=argv[1];
X	signal(SIGINT, endit);
X	tcpsource();
X}
Xtcpsource()
X{
X	int i, cc;
X	int ret, bitmask;
X	struct hostent *hp;
X	char bb[16];
X
X	sinsource.sun_family = AF_UNIX;
X	sinsink.sun_family = AF_UNIX;
X
X	for(i = 0; i< TESTSIZE;i++) {
X		sinkbuf[i] = 0;
X		sourcebuf[i] = i;
X	}
X	s = socket(AF_UNIX, SOCK_STREAM, 0);
X	if (s == -1) {
X		perror("Frist socket() failed!");
X		exit(1);
X	}
X	strcpy(sinsource.sun_path,PORT);
X	strcpy(sinsink.sun_path,PORT);
X
X
X	if(connect(s, &sinsource, sizeof(struct sockaddr_un)) == -1) {
X		perror("Connect failed on sinsource!");
X		exit(1);
X	}
X
X
X	i=128;
X	printf("hit return\n");
X	gets(bb);
Xhere:
X	bitmask = 1 << s;
X	ret = select(32, 0, &bitmask, 0, &timeout);
X	printf("select = %d, bitmask=%d\n",ret,bitmask);
X	if(ret) {
X		cc = write(s,sourcebuf, i); /* */
X		if(cc > 0) {
X			printf("%d characters sent\n", cc);
X		}else {
X			perror("Send failed!");
X			exit(1);
X		}
X	}
X	goto here;
X	close(s);
X	exit(0);
X}
Xendit()
X{
X	close(s);
X	exit(0);
X}
+ END-OF-FILE tcpsend.c
chmod 'u=rw,g=r,o=r' 'tcpsend.c'
echo '	-rw-r--r--   1 bes      HSJ         1396 Oct 11 20:45 tcpsend.c        (as sent)'
echo '	\c'
/bin/ls -l tcpsend.c
exit 0
-- 
Bradley Smith
Telecommunications Solutions Development
AT&T Bell Labs, Holmdel, NJ 
201-949-0090 att!holin!bes or bes at holin.ATT.COM