void
main(int argc, char **argv)
{
static char data[1024], dir[1024], ndir[1024];
int ctl, nctl, fd;
verbose = 1;
if(!verbose){
close(1);
fd = open("/dev/null", O_WRONLY);
if(fd != 1){
dup2(fd, 1);
close(fd);
}
}
argc--, argv++;
printf("listen started\n");
ctl = announce9(argv[0], dir, 0);
if(ctl < 0){
fprintf(stderr, "announce %s: %r", argv[0]);
exit(1);
}
for(;;){
nctl = listen9(dir, ndir, 0);
if(nctl < 0){
fprintf(stderr, "listen %s: %r", argv[0]);
exit(1);
}
//switch(rfork(RFFDG|RFPROC|RFNOWAIT|RFENVG|RFNAMEG|RFNOTEG)){
switch(fork()){
case -1:
reject9(nctl, ndir, "host overloaded");
close(nctl);
continue;
case 0:
fd = accept9(nctl, ndir);
if(fd < 0){
fprintf(stderr, "accept %s: can't open %s/data: %r\n",
argv[0], ndir);
exit(1);
}
printf("incoming call for %s from %s in %s\n", argv[0],
remoteaddr(ndir), ndir);
//fprintf(nctl, "keepalive");
close(ctl);
close(nctl);
//putenv("net", ndir);
/* this is for children that open /dev/cons. Too bad.
snprintf(data, sizeof data, "%s/data", ndir);
bind(data, "/dev/cons", MREPL);
*/
dup2(fd, 0);
dup2(fd, 1);
dup2(fd, 2);
close(fd);
execv(argv[1], argv+1);
// if(argv[1][0] != '/')
// exec(smprintf("%s", argv[1]), argv+1);
fprintf(stderr, "exec: %r\n");
exit(1);
default:
/* reap any available children */
while (waitpid(-1, 0, WNOHANG) > 0)
;
close(nctl);
break;
}
}
}
int main()
{
int ret;
int afd, dfd, lcfd, listen_fd;
char adir[40], ldir[40];
int n;
char buf[256];
/* We'll use this to see if we actually did epoll_waits instead of blocking
* calls. It's not 100%, but with a human on the other end, it should be
* fine. */
bool has_epolled = FALSE;
#ifdef PLAN9NET
printf("Using Plan 9's networking stack\n");
/* This clones a conversation (opens /net/tcp/clone), then reads the cloned
* fd (which is the ctl) to givure out the conv number (the line), then
* writes "announce [addr]" into ctl. This "announce" command often has a
* "bind" in it too. plan9 bind just sets the local addr/port. TCP
* announce also does this. Returns the ctlfd. */
afd = announce9("tcp!*!23", adir, 0);
if (afd < 0) {
perror("Announce failure");
return -1;
}
printf("Announced on line %s\n", adir);
#else
printf("Using the BSD socket shims over Plan 9's networking stack\n");
int srv_socket, con_socket;
struct sockaddr_in dest, srv = {0};
srv.sin_family = AF_INET;
srv.sin_addr.s_addr = htonl(INADDR_ANY);
srv.sin_port = htons(23);
socklen_t socksize = sizeof(struct sockaddr_in);
/* Equiv to cloning a converstation in plan 9. The shim returns the data FD
* for the conversation. */
srv_socket = socket(AF_INET, SOCK_STREAM | SOCK_NONBLOCK, 0);
if (srv_socket < 0) {
perror("Socket failure");
return -1;
}
/* bind + listen is equiv to announce() in plan 9. Note that the "bind"
* command is used, unlike in the plan9 announce. */
/* Binds our socket to the given addr/port in srv. */
ret = bind(srv_socket, (struct sockaddr*)&srv, sizeof(struct sockaddr_in));
if (ret < 0) {
perror("Bind failure");
return -1;
}
/* marks the socket as a listener/server */
ret = listen(srv_socket, 1);
if (ret < 0) {
perror("Listen failure");
return -1;
}
printf("Listened on port %d\n", ntohs(srv.sin_port));
#endif
/* at this point, the server has done all the prep necessary to be able to
* sleep/block/wait on an incoming connection. */
#define EP_SET_SZ 10 /* this is actually the ID of the largest FD */
int epfd = epoll_create(EP_SET_SZ);
struct epoll_event ep_ev;
struct epoll_event results[EP_SET_SZ];
if (epfd < 0) {
perror("epoll_create");
exit(-1);
}
ep_ev.events = EPOLLIN | EPOLLET;
#ifdef PLAN9NET
snprintf(buf, sizeof(buf), "%s/listen", adir);
listen_fd = open(buf, O_PATH);
if (listen_fd < 0){
perror("listen fd");
return -1;
}
/* This is a little subtle. We're putting a tap on the listen file /
* listen_fd. When this fires, we get an event because of that listen_fd.
* But we don't actually listen or do anything to that listen_fd. It's
* solely for monitoring. We open a path, below, and we'll reattempt to do
* *that* operation when someone tells us that our listen tap fires. */
ep_ev.data.fd = listen_fd;
if (epoll_ctl(epfd, EPOLL_CTL_ADD, listen_fd, &ep_ev)) {
perror("epoll_ctl_add listen");
exit(-1);
}
has_epolled = FALSE;
while (1) {
/* Opens the conversation's listen file. This blocks til someone
* connects. When they do, a new conversation is created, and that open
* returned an FD for the new conv's ctl. listen() reads that to find
* out the conv number (the line) for this new conv. listen() returns
* the ctl for this new conv.
*
* Non-block is for the act of listening, and applies to lcfd. */
lcfd = listen9(adir, ldir, O_NONBLOCK);
if (lcfd >= 0)
break;
if (errno != EAGAIN) {
perror("Listen failure");
return -1;
}
if (epoll_wait(epfd, results, EP_SET_SZ, -1) != 1) {
perror("epoll_wait");
exit(-1);
}
has_epolled = TRUE;
assert(results[0].data.fd == listen_fd);
assert(results[0].events == EPOLLIN);
}
printf("Listened and got line %s\n", ldir);
assert(has_epolled);
/* No longer need listen_fd. You should CTL_DEL before closing. */
if (epoll_ctl(epfd, EPOLL_CTL_DEL, listen_fd, &ep_ev)) {
perror("epoll_ctl_del");
exit(-1);
}
close(listen_fd);
/* Writes "accept [NUM]" into the ctlfd, then opens the conv's data file and
* returns that fd. Writing "accept" is a noop for most of our protocols.
* */
dfd = accept9(lcfd, ldir);
if (dfd < 0) {
perror("Accept failure");
return -1;
}
#else
ep_ev.data.fd = srv_socket;
if (epoll_ctl(epfd, EPOLL_CTL_ADD, srv_socket, &ep_ev)) {
perror("epoll_ctl_add srv_socket");
exit(-1);
}
has_epolled = FALSE;
while (1) {
/* returns an FD for a new socket. */
dfd = accept(srv_socket, (struct sockaddr*)&dest, &socksize);
if (dfd >= 0)
break;
if (errno != EAGAIN) {
perror("Accept failure");
return -1;
}
if (epoll_wait(epfd, results, EP_SET_SZ, -1) != 1) {
perror("epoll_wait");
exit(-1);
}
has_epolled = TRUE;
assert(results[0].data.fd == srv_socket);
assert(results[0].events == EPOLLIN);
}
printf("Accepted and got dfd %d\n", dfd);
assert(has_epolled);
if (epoll_ctl(epfd, EPOLL_CTL_DEL, srv_socket, &ep_ev)) {
perror("epoll_ctl_del");
while (1);
exit(-1);
}
#endif
/* In lieu of accept4, we set the new socket's nonblock status manually.
* Both OSs do this. */
ret = fcntl(dfd, F_SETFL, O_NONBLOCK);
if (ret < 0) {
perror("setfl dfd");
exit(-1);
}
ep_ev.data.fd = dfd;
if (epoll_ctl(epfd, EPOLL_CTL_ADD, dfd, &ep_ev)) {
perror("epoll_ctl_add dvd");
exit(-1);
}
/* echo until EOF */
has_epolled = FALSE;
printf("Server read: ");
while (1) {
while ((n = read(dfd, buf, sizeof(buf))) > 0) {
for (int i = 0; i < n; i++)
printf("%c", buf[i]);
fflush(stdout);
/* Should epoll on this direction too. */
if (write(dfd, buf, n) < 0) {
perror("writing");
exit(-1);
}
}
if (n == 0)
break;
if (epoll_wait(epfd, results, EP_SET_SZ, -1) != 1) {
perror("epoll_wait 2");
exit(-1);
}
has_epolled = TRUE;
assert(results[0].data.fd == dfd);
/* you might get a HUP, but keep on reading! */
}
assert(has_epolled);
if (epoll_ctl(epfd, EPOLL_CTL_DEL, dfd, &ep_ev)) {
perror("epoll_ctl_del dfd");
exit(-1);
}
#ifdef PLAN9NET
close(dfd); /* data fd for the new conv, from listen */
close(lcfd); /* ctl fd for the new conv, from listen */
close(afd); /* ctl fd for the listening conv */
#else
close(dfd); /* new connection socket, from accept */
close(srv_socket);
#endif
}
int main(void)
{
int ret;
int afd, dfd, lcfd, listen_fd;
char adir[40], ldir[40];
int n;
char buf[256];
/* We'll use this to see if we actually did a select instead of blocking
* calls. It's not 100%, but with a human on the other end, it should be
* fine. */
bool has_selected = FALSE;
#ifdef PLAN9NET
printf("Using Plan 9's networking stack\n");
/* This clones a conversation (opens /net/tcp/clone), then reads the cloned
* fd (which is the ctl) to givure out the conv number (the line), then
* writes "announce [addr]" into ctl. This "announce" command often has a
* "bind" in it too. plan9 bind just sets the local addr/port. TCP
* announce also does this. Returns the ctlfd. */
afd = announce9("tcp!*!23", adir, O_NONBLOCK);
if (afd < 0) {
perror("Announce failure");
return -1;
}
printf("Announced on line %s\n", adir);
#else
printf("Using the BSD socket shims over Plan 9's networking stack\n");
int srv_socket;
struct sockaddr_in dest, srv = {0};
srv.sin_family = AF_INET;
srv.sin_addr.s_addr = htonl(INADDR_ANY);
srv.sin_port = htons(23);
socklen_t socksize = sizeof(struct sockaddr_in);
/* Equiv to cloning a converstation in plan 9. The shim returns the data FD
* for the conversation. */
srv_socket = socket(AF_INET, SOCK_STREAM | SOCK_NONBLOCK, 0);
if (srv_socket < 0) {
perror("Socket failure");
return -1;
}
/* bind + listen is equiv to announce() in plan 9. Note that the "bind"
* command is used, unlike in the plan9 announce. */
/* Binds our socket to the given addr/port in srv. */
ret = bind(srv_socket, (struct sockaddr*)&srv, sizeof(struct sockaddr_in));
if (ret < 0) {
perror("Bind failure");
return -1;
}
/* marks the socket as a listener/server */
ret = listen(srv_socket, 1);
if (ret < 0) {
perror("Listen failure");
return -1;
}
printf("Listened on port %d\n", ntohs(srv.sin_port));
#endif
/* at this point, the server has done all the prep necessary to be able to
* sleep/block/wait on an incoming connection. */
fd_set rfds;
#ifdef PLAN9NET
snprintf(buf, sizeof(buf), "%s/listen", adir);
listen_fd = open(buf, O_PATH);
if (listen_fd < 0) {
perror("listen fd");
return -1;
}
FD_ZERO(&rfds);
FD_SET(listen_fd, &rfds);
has_selected = FALSE;
while (1) {
/* Opens the conversation's listen file. This blocks til someone
* connects. When they do, a new conversation is created, and that open
* returned an FD for the new conv's ctl. listen() reads that to find
* out the conv number (the line) for this new conv. listen() returns
* the ctl for this new conv.
*
* Non-block is for the new connection. Not the act of listening. */
lcfd = listen9(adir, ldir, O_NONBLOCK);
if (lcfd >= 0)
break;
if (errno != EAGAIN) {
perror("Listen failure");
return -1;
}
if (select(listen_fd + 1, &rfds, 0, 0, 0) < 0) {
perror("select");
return -1;
}
has_selected = TRUE;
assert(FD_ISSET(listen_fd, &rfds));
}
printf("Listened and got line %s\n", ldir);
assert(has_selected);
/* No longer need listen_fd. */
close(listen_fd);
/* Writes "accept [NUM]" into the ctlfd, then opens the conv's data file and
* returns that fd. Writing "accept" is a noop for most of our protocols.
* */
dfd = accept9(lcfd, ldir);
if (dfd < 0) {
perror("Accept failure");
return -1;
}
#else
FD_ZERO(&rfds);
FD_SET(srv_socket, &rfds);
has_selected = FALSE;
while (1) {
/* returns an FD for a new socket. */
dfd = accept(srv_socket, (struct sockaddr*)&dest, &socksize);
if (dfd >= 0)
break;
if (errno != EAGAIN) {
perror("Accept failure");
return -1;
}
if (select(srv_socket + 1, &rfds, 0, 0, 0) < 0) {
perror("select");
return -1;
}
has_selected = TRUE;
assert(FD_ISSET(srv_socket, &rfds));
}
printf("Accepted and got dfd %d\n", dfd);
assert(has_selected);
/* In lieu of accept4, we set the new socket's nonblock status manually */
ret = fcntl(dfd, F_SETFL, O_NONBLOCK);
if (ret < 0) {
perror("setfl dfd");
exit(-1);
}
#endif
FD_SET(dfd, &rfds);
/* echo until EOF */
has_selected = FALSE;
printf("Server read: ");
while (1) {
while ((n = read(dfd, buf, sizeof(buf))) > 0) {
for (int i = 0; i < n; i++)
printf("%c", buf[i]);
fflush(stdout);
/* Should select on this direction too. */
if (write(dfd, buf, n) < 0) {
perror("writing");
exit(-1);
}
}
if (n == 0)
break;
if (select(dfd + 1, &rfds, 0, 0, 0) < 0) {
perror("select 2");
exit(-1);
}
has_selected = TRUE;
assert(FD_ISSET(dfd, &rfds));
/* you might get a HUP, but keep on reading! */
}
assert(has_selected);
#ifdef PLAN9NET
close(dfd); /* data fd for the new conv, from listen */
close(lcfd); /* ctl fd for the new conv, from listen */
close(afd); /* ctl fd for the listening conv */
#else
close(dfd); /* new connection socket, from accept */
close(srv_socket);
#endif
}
int main()
{
int ret;
int afd, dfd, lcfd;
char adir[40], ldir[40];
int n;
char buf[256];
char debugbuf[256];
#ifdef PLAN9NET
/* This clones a conversation (opens /net/tcp/clone), then reads the cloned
* fd (which is the ctl) to givure out the conv number (the line), then
* writes "announce [addr]" into ctl. This "announce" command often has a
* "bind" in it too. plan9 bind just sets the local addr/port. TCP
* announce also does this. Returns the ctlfd. */
afd = announce9("tcp!*!23", adir, 0);
if (afd < 0) {
perror("Announce failure");
return -1;
}
printf("Announced on line %s\n", adir);
#else
int srv_socket, con_socket;
struct sockaddr_in dest, srv = {0};
srv.sin_family = AF_INET;
srv.sin_addr.s_addr = htonl(INADDR_ANY);
srv.sin_port = htons(23);
socklen_t socksize = sizeof(struct sockaddr_in);
/* Equiv to cloning a converstation in plan 9. The shim returns the data FD
* for the conversation. */
srv_socket = socket(AF_INET, SOCK_STREAM, 0);
if (srv_socket < 0) {
perror("Socket failure");
return -1;
}
/* bind + listen is equiv to announce() in plan 9. Note that the "bind"
* command is used, unlike in the plan9 announce. */
/* Binds our socket to the given addr/port in srv. */
ret = bind(srv_socket, (struct sockaddr*)&srv, sizeof(struct sockaddr_in));
if (ret < 0) {
perror("Bind failure");
return -1;
}
/* marks the socket as a listener/server */
ret = listen(srv_socket, 1);
if (ret < 0) {
perror("Listen failure");
return -1;
}
#endif
/* at this point, the server has done all the prep necessary to be able to
* sleep/block/wait on an incoming connection. */
#ifdef PLAN9NET
/* Opens the conversation's listen file. This blocks til someone connects.
* When they do, a new conversation is created, and that open returned an FD
* for the new conv's ctl. listen() reads that to find out the conv number
* (the line) for this new conv. listen() returns the ctl for this new
* conv. */
lcfd = listen9(adir, ldir, 0);
if (lcfd < 0) {
perror("Listen failure");
return -1;
}
printf("Listened and got line %s\n", ldir);
/* Writes "accept [NUM]" into the ctlfd, then opens the conv's data file and
* returns that fd. Writing "accept" is a noop for most of our protocols.
* */
dfd = accept9(lcfd, ldir);
if (dfd < 0) {
perror("Accept failure");
return -1;
}
#else
/* returns an FD for a new socket. */
dfd = accept(srv_socket, (struct sockaddr*)&dest, &socksize);
if (dfd < 0) {
perror("Accept failure");
return -1;
}
#endif
/* echo until EOF */
while ((n = read(dfd, buf, sizeof(buf))) > 0) {
snprintf(debugbuf, n, "%s", buf);
printf("Server read: %s", debugbuf);
write(dfd, buf, n);
}
#ifdef PLAN9NET
close(dfd); /* data fd for the new conv, from listen */
close(lcfd); /* ctl fd for the new conv, from listen */
close(afd); /* ctl fd for the listening conv */
#else
close(dfd); /* new connection socket, from accept */
close(srv_socket);
#endif
}