static int
comm_check_incoming_select_handlers(int nfds, int *fds)
{
int i;
int fd;
int maxfd = 0;
PF *hdl = NULL;
fd_set read_mask;
fd_set write_mask;
FD_ZERO(&read_mask);
FD_ZERO(&write_mask);
incoming_sockets_accepted = 0;
for (i = 0; i < nfds; i++) {
fd = fds[i];
if (fd_table[fd].read_handler) {
FD_SET(fd, &read_mask);
if (fd > maxfd)
maxfd = fd;
}
if (fd_table[fd].write_handler) {
FD_SET(fd, &write_mask);
if (fd > maxfd)
maxfd = fd;
}
}
if (maxfd++ == 0)
return -1;
#if !ALARM_UPDATES_TIME
getCurrentTime();
#endif
statCounter.syscalls.selects++;
if (select(maxfd, &read_mask, &write_mask, NULL, &zero_tv) < 1)
return incoming_sockets_accepted;
for (i = 0; i < nfds; i++) {
fd = fds[i];
if (FD_ISSET(fd, &read_mask)) {
if ((hdl = fd_table[fd].read_handler) != NULL) {
fd_table[fd].read_handler = NULL;
commUpdateReadBits(fd, NULL);
hdl(fd, fd_table[fd].read_data);
} else {
debug(5, 1) ("comm_select_incoming: FD %d NULL read handler\n",
fd);
}
}
if (FD_ISSET(fd, &write_mask)) {
if ((hdl = fd_table[fd].write_handler) != NULL) {
fd_table[fd].write_handler = NULL;
commUpdateWriteBits(fd, NULL);
hdl(fd, fd_table[fd].write_data);
} else {
debug(5, 1) ("comm_select_incoming: FD %d NULL write handler\n",
fd);
}
}
}
return incoming_sockets_accepted;
}
void
fd_close(int fd)
{
fde *F = &fd_table[fd];
if (F->type == FD_FILE) {
assert(F->read_handler == NULL);
assert(F->write_handler == NULL);
}
debug(51, 3) ("fd_close FD %d %s\n", fd, F->desc);
F->flags.open = 0;
fdUpdateBiggest(fd, 0);
Number_FD--;
commUpdateReadBits(fd, NULL);
commUpdateWriteBits(fd, NULL);
memset(F, '\0', sizeof(fde));
F->timeout = 0;
}
/* Select on all sockets; call handlers for those that are ready. */
int
comm_select(int msec)
{
fd_set readfds;
fd_set pendingfds;
fd_set writefds;
#if DELAY_POOLS
BIT_ARRAY slowfds;
#endif
PF *hdl = NULL;
int fd;
int maxfd;
int num;
int pending;
int callicp = 0, callhttp = 0;
int calldns = 0;
int maxindex;
int k;
int j;
#if DEBUG_FDBITS
int i;
#endif
fd_mask *fdsp;
fd_mask *pfdsp;
fd_mask tmask;
static time_t last_timeout = 0;
struct timeval poll_time;
double timeout = current_dtime + (msec / 1000.0);
fde *F;
#if DELAY_POOLS
BA_INIT(slowfds,SQUID_NUMFD);
#endif
do {
#if !ALARM_UPDATES_TIME
double start;
getCurrentTime();
start = current_dtime;
#endif
#if DELAY_POOLS
BA_ZERO(slowfds);
#endif
/* Handle any fs callbacks that need doing */
storeDirCallback();
if (commCheckICPIncoming)
comm_select_icp_incoming();
if (commCheckDNSIncoming)
comm_select_dns_incoming();
if (commCheckHTTPIncoming)
comm_select_http_incoming();
callicp = calldns = callhttp = 0;
maxfd = Biggest_FD + 1;
xmemcpy(&readfds, &global_readfds,
howmany(maxfd, FD_MASK_BITS) * FD_MASK_BYTES);
xmemcpy(&writefds, &global_writefds,
howmany(maxfd, FD_MASK_BITS) * FD_MASK_BYTES);
/* remove stalled FDs, and deal with pending descriptors */
pending = 0;
FD_ZERO(&pendingfds);
maxindex = howmany(maxfd, FD_MASK_BITS);
fdsp = (fd_mask *) & readfds;
for (j = 0; j < maxindex; j++) {
if ((tmask = fdsp[j]) == 0)
continue; /* no bits here */
for (k = 0; k < FD_MASK_BITS; k++) {
if (!EBIT_TEST(tmask, k))
continue;
/* Found a set bit */
fd = (j * FD_MASK_BITS) + k;
switch (commDeferRead(fd)) {
case 0:
break;
case 1:
FD_CLR(fd, &readfds);
break;
#if DELAY_POOLS
case -1:
BA_SET(fd, slowfds);
break;
#endif
default:
fatalf("bad return value from commDeferRead(FD %d)\n", fd);
}
if (FD_ISSET(fd, &readfds) && fd_table[fd].flags.read_pending) {
FD_SET(fd, &pendingfds);
pending++;
}
}
}
#if DEBUG_FDBITS
for (i = 0; i < maxfd; i++) {
/* Check each open socket for a handler. */
#if DELAY_POOLS
if (fd_table[i].read_handler && commDeferRead(i) != 1) {
#else
if (fd_table[i].read_handler && !commDeferRead(i)) {
#endif
assert(FD_ISSET(i, &readfds));
}
if (fd_table[i].write_handler) {
assert(FD_ISSET(i, &writefds));
}
}
#endif
if (nreadfds + nwritefds == 0) {
assert(shutting_down);
#if DELAY_POOLS
BA_FREE(slowfds);
#endif
return COMM_SHUTDOWN;
}
if (msec > MAX_POLL_TIME)
msec = MAX_POLL_TIME;
if (pending)
msec = 0;
for (;;) {
poll_time.tv_sec = msec / 1000;
poll_time.tv_usec = (msec % 1000) * 1000;
statCounter.syscalls.selects++;
num = select(maxfd, &readfds, &writefds, NULL, &poll_time);
statCounter.select_loops++;
if (num >= 0 || pending > 0)
break;
if (ignoreErrno(errno))
break;
debug(50, 0) ("comm_select: select failure: %s\n",
xstrerror());
examine_select(&readfds, &writefds);
#if DELAY_POOLS
BA_FREE(slowfds);
#endif
return COMM_ERROR;
/* NOTREACHED */
}
if (num < 0 && !pending)
continue;
debug(5, num ? 5 : 8) ("comm_select: %d+%d FDs ready at %d\n",
num, pending, (int) squid_curtime);
statHistCount(&statCounter.select_fds_hist, num);
/* Check lifetime and timeout handlers ONCE each second.
* Replaces brain-dead check every time through the loop! */
if (squid_curtime > last_timeout) {
last_timeout = squid_curtime;
checkTimeouts();
}
if (num == 0 && pending == 0)
continue;
/* Scan return fd masks for ready descriptors */
fdsp = (fd_mask *) & readfds;
pfdsp = (fd_mask *) & pendingfds;
maxindex = howmany(maxfd, FD_MASK_BITS);
for (j = 0; j < maxindex; j++) {
if ((tmask = (fdsp[j] | pfdsp[j])) == 0)
continue; /* no bits here */
for (k = 0; k < FD_MASK_BITS; k++) {
if (tmask == 0)
break; /* no more bits left */
if (!EBIT_TEST(tmask, k))
continue;
/* Found a set bit */
fd = (j * FD_MASK_BITS) + k;
EBIT_CLR(tmask, k); /* this will be done */
#if DEBUG_FDBITS
debug(5, 9) ("FD %d bit set for reading\n", fd);
assert(FD_ISSET(fd, &readfds));
#endif
if (fdIsIcp(fd)) {
callicp = 1;
continue;
}
if (fdIsDns(fd)) {
calldns = 1;
continue;
}
if (fdIsHttp(fd)) {
callhttp = 1;
continue;
}
F = &fd_table[fd];
debug(5, 6) ("comm_select: FD %d ready for reading\n", fd);
if (NULL == (hdl = F->read_handler))
(void) 0;
#if DELAY_POOLS
else if (BA_ISSET(fd, slowfds))
commAddSlowFd(fd);
#endif
else {
F->read_handler = NULL;
commUpdateReadBits(fd, NULL);
hdl(fd, F->read_data);
statCounter.select_fds++;
if (commCheckICPIncoming)
comm_select_icp_incoming();
if (commCheckDNSIncoming)
comm_select_dns_incoming();
if (commCheckHTTPIncoming)
comm_select_http_incoming();
}
}
}
fdsp = (fd_mask *) & writefds;
for (j = 0; j < maxindex; j++) {
if ((tmask = fdsp[j]) == 0)
continue; /* no bits here */
for (k = 0; k < FD_MASK_BITS; k++) {
if (tmask == 0)
break; /* no more bits left */
if (!EBIT_TEST(tmask, k))
continue;
/* Found a set bit */
fd = (j * FD_MASK_BITS) + k;
EBIT_CLR(tmask, k); /* this will be done */
#if DEBUG_FDBITS
debug(5, 9) ("FD %d bit set for writing\n", fd);
assert(FD_ISSET(fd, &writefds));
#endif
if (fdIsIcp(fd)) {
callicp = 1;
continue;
}
if (fdIsDns(fd)) {
calldns = 1;
continue;
}
if (fdIsHttp(fd)) {
callhttp = 1;
continue;
}
F = &fd_table[fd];
debug(5, 5) ("comm_select: FD %d ready for writing\n", fd);
if ((hdl = F->write_handler)) {
F->write_handler = NULL;
commUpdateWriteBits(fd, NULL);
hdl(fd, F->write_data);
statCounter.select_fds++;
if (commCheckICPIncoming)
comm_select_icp_incoming();
if (commCheckDNSIncoming)
comm_select_dns_incoming();
if (commCheckHTTPIncoming)
comm_select_http_incoming();
}
}
}
if (callicp)
comm_select_icp_incoming();
if (calldns)
comm_select_dns_incoming();
if (callhttp)
comm_select_http_incoming();
#if DELAY_POOLS
while ((fd = commGetSlowFd()) != -1) {
F = &fd_table[fd];
debug(5, 6) ("comm_select: slow FD %d selected for reading\n", fd);
if ((hdl = F->read_handler)) {
F->read_handler = NULL;
commUpdateReadBits(fd, NULL);
hdl(fd, F->read_data);
statCounter.select_fds++;
if (commCheckICPIncoming)
comm_select_icp_incoming();
if (commCheckDNSIncoming)
comm_select_dns_incoming();
if (commCheckHTTPIncoming)
comm_select_http_incoming();
}
}
#endif
#if !ALARM_UPDATES_TIME
getCurrentTime();
statCounter.select_time += (current_dtime - start);
#endif
#if DELAY_POOLS
BA_FREE(slowfds);
#endif
return COMM_OK;
}
while (timeout > current_dtime);
debug(5, 8) ("comm_select: time out: %d\n", (int) squid_curtime);
#if DELAY_POOLS
BA_FREE(slowfds);
#endif
return COMM_TIMEOUT;
}
#endif
static void
#if HAVE_POLL
comm_poll_dns_incoming(void)
#else
comm_select_dns_incoming(void)
#endif
{
int nfds = 0;
int fds[2];
int nevents;
dns_io_events = 0;
if (DnsSocket < 0)
return;
fds[nfds++] = DnsSocket;
#if HAVE_POLL
nevents = comm_check_incoming_poll_handlers(nfds, fds);
#else
nevents = comm_check_incoming_select_handlers(nfds, fds);
#endif
if (nevents < 0)
return;
incoming_dns_interval += Config.comm_incoming.dns_average - nevents;
if (incoming_dns_interval < Config.comm_incoming.dns_min_poll)
incoming_dns_interval = Config.comm_incoming.dns_min_poll;
if (incoming_dns_interval > MAX_INCOMING_INTERVAL)
incoming_dns_interval = MAX_INCOMING_INTERVAL;
if (nevents > INCOMING_DNS_MAX)
nevents = INCOMING_DNS_MAX;
statHistCount(&statCounter.comm_dns_incoming, nevents);
}
