void handle_request(char *buf)
{
const char *delims = "|\r\n\t ";
switch (buf[0]) {
case 'S':
/* Register server|type|weight|sticky|extras */
{
char *tok, *servername = NULL;
enum locator_servicetype_t servicetype = ST_MAX;
int serverweight = 0;
enum locator_sticky_t sticky = LOC_ROAMING;
char *serverextras = NULL;
tok = strtok(buf, delims); if (tok) { tok = strtok(NULL, delims); }
if (tok) { servername = tok; tok = strtok(NULL, delims); }
if (tok) { servicetype = get_servicetype(tok); tok = strtok(NULL, delims); }
if (tok) { serverweight = atoi(tok); tok = strtok(NULL, delims); }
if (tok) { sticky = ((atoi(tok) == 1) ? LOC_STICKY : LOC_ROAMING); tok = strtok(NULL, delims); }
if (tok) { serverextras = tok; tok = strtok(NULL, delims); }
if (servername && (servicetype != ST_MAX)) {
dbgprintf("Registering server '%s' handling %s (weight %d, %s)\n",
servername, servicetype_names[servicetype], serverweight,
(sticky == LOC_STICKY ? "sticky" : "not sticky"));
register_server(servername, servicetype, serverweight, sticky, serverextras);
strcpy(buf, "OK");
}
else strcpy(buf, "BADSYNTAX");
}
break;
case 'D': case 'U': case 'F':
/* Down/Up/Forget server|type */
{
char *tok, *servername = NULL;
enum locator_servicetype_t servicetype = ST_MAX;
tok = strtok(buf, delims); if (tok) { tok = strtok(NULL, delims); }
if (tok) { servername = tok; tok = strtok(NULL, delims); }
if (tok) { servicetype = get_servicetype(tok); tok = strtok(NULL, delims); }
if (servername && (servicetype != ST_MAX)) {
downup_server(servername, servicetype, buf[0]);
strcpy(buf, "OK");
}
else strcpy(buf, "BADSYNTAX");
}
break;
case 'H':
/* Register host|type|server */
{
char *tok, *hostname = NULL, *servername = NULL;
enum locator_servicetype_t servicetype = ST_MAX;
tok = strtok(buf, delims); if (tok) { tok = strtok(NULL, delims); }
if (tok) { hostname = tok; tok = strtok(NULL, delims); }
if (tok) { servicetype = get_servicetype(tok); tok = strtok(NULL, delims); }
if (tok) { servername = tok; tok = strtok(NULL, delims); }
if (hostname && (servicetype != ST_MAX) && servername) {
dbgprintf("Registering type/host %s/%s handled by server %s\n",
servicetype_names[servicetype], hostname, servername);
register_host(hostname, servicetype, servername);
strcpy(buf, "OK");
}
else strcpy(buf, "BADSYNTAX");
}
break;
case 'M':
/* Rename host|type|newhostname */
{
char *tok, *oldhostname = NULL, *newhostname = NULL;
enum locator_servicetype_t servicetype = ST_MAX;
tok = strtok(buf, delims); if (tok) { tok = strtok(NULL, delims); }
if (tok) { oldhostname = tok; tok = strtok(NULL, delims); }
if (tok) { servicetype = get_servicetype(tok); tok = strtok(NULL, delims); }
if (tok) { newhostname = tok; tok = strtok(NULL, delims); }
if (oldhostname && (servicetype != ST_MAX) && newhostname) {
dbgprintf("Renaming type/host %s/%s to %s\n",
servicetype_names[servicetype], oldhostname, newhostname);
if (rename_host(oldhostname, servicetype, newhostname)) {
strcpy(buf, "OK");
}
else {
strcpy(buf, "FAILED");
}
}
else strcpy(buf, "BADSYNTAX");
}
break;
case 'X':
case 'Q':
/* Query type|host */
{
char *tok, *hostname = NULL;
enum locator_servicetype_t servicetype = ST_MAX;
int extquery = (buf[0] == 'X');
serverinfo_t *res = NULL;
tok = strtok(buf, delims); if (tok) { tok = strtok(NULL, delims); }
if (tok) { servicetype = get_servicetype(tok); tok = strtok(NULL, delims); }
if (tok) { hostname = tok; tok = strtok(NULL, delims); }
if ((servicetype != ST_MAX) && hostname) {
res = find_server_by_host(servicetype, hostname);
if (res) {
/* This host is fixed on a specific server ... */
if (res->serveractualweight > 0) {
/* ... and that server is UP */
sprintf(buf, "!|%s", res->servername);
}
else {
/* ... and the server is DOWN, so we cannot service the request */
strcpy(buf, "?");
}
}
else {
/* Roaming or un-registered host */
res = find_server_by_type(servicetype);
if (res) {
if (res->sticky == LOC_STICKY) {
dbgprintf("Host %s/%s now fixed on server %s\n",
hostname, servicetype_names[servicetype], res->servername);
register_host(hostname, servicetype, res->servername);
}
sprintf(buf, "*|%s", res->servername);
}
else {
strcpy(buf, "?");
}
}
if (res && extquery) {
int blen = strlen(buf);
snprintf(buf+blen, sizeof(buf)-blen-1, "|%s", res->serverextras);
}
}
else strcpy(buf, "BADSYNTAX");
}
break;
case 'p':
/* Locator ping */
sprintf(buf, "PONG|%s", VERSION);
break;
case '@':
/* Save state */
save_state();
strcpy(buf, "OK");
break;
default:
strcpy(buf, "BADREQUEST");
break;
}
}
int main(int argc, char *argv[])
{
char buf[1024];
int done = 0;
char *res;
if (argc < 2) {
printf("Usage: %s IP:PORT\n", argv[0]);
return 1;
}
if (locator_init(argv[1]) == -1) {
printf("Locator ping failed\n");
return 1;
}
else {
printf("Locator is available\n");
}
while (!done) {
char *p, *p1, *p2, *p3, *p4, *p5, *p6, *p7;
char *extras;
printf("Commands:\n");
printf(" r(egister) s servername type weight sticky\n");
printf(" r(egister) h servername type hostname\n");
printf(" d(own) servername type\n");
printf(" u(p) servername type\n");
printf(" f(orget) servername type\n");
printf(" q(uery) hostname type\n");
printf(" x(query) hostname type\n");
printf(" p(ing)\n");
printf(" s(ave state)\n");
printf(">"); fflush(stdout);
done = (fgets(buf, sizeof(buf), stdin) == NULL); if (done) continue;
p = strchr(buf, '\n'); if (p) *p = '\0';
p1 = p2 = p3 = p4 = p5 = p6 = p7 = NULL;
p1 = strtok(buf, " ");
if (p1) p2 = strtok(NULL, " ");
if (p2) p3 = strtok(NULL, " ");
if (p3) p4 = strtok(NULL, " ");
if (p4) p5 = strtok(NULL, " ");
if (p5) p6 = strtok(NULL, " ");
if (p6) p7 = strtok(NULL, "\r\n");
switch (*p1) {
case 'R': case 'r':
if (*p2 == 's') {
enum locator_servicetype_t svc;
enum locator_sticky_t sticky;
int weight;
svc = get_servicetype(p4);
weight = (p5 ? atoi(p5) : 1);
sticky = ((p6 && (atoi(p6) == 1)) ? LOC_STICKY : LOC_ROAMING);
printf("%s\n", locator_register_server(p3, svc, weight, sticky, p7) ? "Failed" : "OK");
}
else if (*p2 == 'h') {
printf("%s\n", locator_register_host(p5, get_servicetype(p4), p3) ? "Failed" : "OK");
}
break;
case 'D': case 'd':
printf("%s\n", locator_serverdown(p2, get_servicetype(p3)) ? "Failed" : "OK");
break;
case 'U': case 'u':
printf("%s\n", locator_serverup(p2, get_servicetype(p3)) ? "Failed" : "OK");
break;
case 'F': case 'f':
printf("%s\n", locator_serverforget(p2, get_servicetype(p3)) ? "Failed" : "OK");
break;
case 'Q': case 'q':
case 'X': case 'x':
extras = NULL;
res = locator_query(p2, get_servicetype(p3), (*p1 == 'x') ? &extras : NULL);
if (res) {
printf("Result: %s\n", res);
if (extras) printf(" Extras gave: %s\n", extras);
}
else {
printf("Failed\n");
}
break;
case 'P': case 'p':
p = locator_cmd("p");
if (p == NULL) printf("Failed\n"); else printf("OK: %s\n", p);
break;
case 'S': case 's':
p = locator_cmd("@");
if (p == NULL) printf("Failed\n"); else printf("OK: %s\n", p);
break;
}
}
return 0;
}
void load_state(void)
{
char *tmpdir;
char *fn;
FILE *fd;
char buf[4096];
char *tname, *sname, *sconfweight, *sactweight, *ssticky, *sextra, *hname;
enum locator_servicetype_t stype;
tmpdir = xgetenv("XYMONTMP"); if (!tmpdir) tmpdir = "/tmp";
fn = (char *)malloc(strlen(tmpdir) + 100);
sprintf(fn, "%s/locator.servers.chk", tmpdir);
fd = fopen(fn, "r");
if (fd) {
while (fgets(buf, sizeof(buf), fd)) {
serverinfo_t *srv;
tname = sname = sconfweight = sactweight = ssticky = sextra = NULL;
tname = strtok(buf, "|\n");
if (tname) sname = strtok(NULL, "|\n");
if (sname) sconfweight = strtok(NULL, "|\n");
if (sconfweight) sactweight = strtok(NULL, "|\n");
if (sactweight) ssticky = strtok(NULL, "|\n");
if (ssticky) sextra = strtok(NULL, "\n");
if (tname && sname && sconfweight && sactweight && ssticky) {
enum locator_sticky_t sticky = (atoi(ssticky) == 1) ? LOC_STICKY : LOC_ROAMING;
stype = get_servicetype(tname);
srv = register_server(sname, stype, atoi(sconfweight), sticky, sextra);
srv->serveractualweight = atoi(sactweight);
dbgprintf("Loaded server %s/%s (cweight %d, aweight %d, %s)\n",
srv->servername, tname, srv->serverconfweight, srv->serveractualweight,
(srv->sticky ? "sticky" : "not sticky"));
}
}
fclose(fd);
}
for (stype = 0; (stype < ST_MAX); stype++) recalc_current(stype);
sprintf(fn, "%s/locator.hosts.chk", tmpdir);
fd = fopen(fn, "r");
if (fd) {
while (fgets(buf, sizeof(buf), fd)) {
tname = hname = sname = NULL;
tname = strtok(buf, "|\n");
if (tname) hname = strtok(NULL, "|\n");
if (hname) sname = strtok(NULL, "|\n");
if (tname && hname && sname) {
enum locator_servicetype_t stype = get_servicetype(tname);
register_host(hname, stype, sname);
dbgprintf("Loaded host %s/%s for server %s\n", hname, tname, sname);
}
}
fclose(fd);
}
}
int main(int argc, char *argv[])
{
int daemonize = 0;
char *pidfile = NULL;
char *envarea = NULL;
int cnid = -1;
pcre *msgfilter = NULL;
pcre *stdfilter = NULL;
int argi;
struct sigaction sa;
RbtIterator handle;
/* Dont save the error buffer */
save_errbuf = 0;
/* Create the peer container */
peers = rbtNew(name_compare);
for (argi=1; (argi < argc); argi++) {
if (argnmatch(argv[argi], "--debug")) {
debug = 1;
}
else if (argnmatch(argv[argi], "--channel=")) {
char *cn = strchr(argv[argi], '=') + 1;
for (cnid = C_STATUS; (channelnames[cnid] && strcmp(channelnames[cnid], cn)); cnid++) ;
if (channelnames[cnid] == NULL) cnid = -1;
}
else if (argnmatch(argv[argi], "--daemon")) {
daemonize = 1;
}
else if (argnmatch(argv[argi], "--no-daemon")) {
daemonize = 0;
}
else if (argnmatch(argv[argi], "--pidfile=")) {
char *p = strchr(argv[argi], '=');
pidfile = strdup(p+1);
}
else if (argnmatch(argv[argi], "--log=")) {
char *p = strchr(argv[argi], '=');
logfn = strdup(p+1);
}
else if (argnmatch(argv[argi], "--env=")) {
char *p = strchr(argv[argi], '=');
loadenv(p+1, envarea);
}
else if (argnmatch(argv[argi], "--area=")) {
char *p = strchr(argv[argi], '=');
envarea = strdup(p+1);
}
else if (argnmatch(argv[argi], "--locator=")) {
char *p = strchr(argv[argi], '=');
locator_init(p+1);
locatorbased = 1;
}
else if (argnmatch(argv[argi], "--service=")) {
char *p = strchr(argv[argi], '=');
locatorservice = get_servicetype(p+1);
}
else if (argnmatch(argv[argi], "--filter=")) {
char *p = strchr(argv[argi], '=');
msgfilter = compileregex(p+1);
if (!msgfilter) {
errprintf("Invalid filter (bad expression): %s\n", p+1);
}
else {
stdfilter = compileregex("^@@(logrotate|shutdown|drophost|droptest|renamehost|renametest)");
}
}
else {
char *childcmd;
char **childargs;
int i = 0;
childcmd = argv[argi];
childargs = (char **) calloc((1 + argc - argi), sizeof(char *));
while (argi < argc) { childargs[i++] = argv[argi++]; }
addlocalpeer(childcmd, childargs);
}
}
/* Sanity checks */
if (cnid == -1) {
errprintf("No channel/unknown channel specified\n");
return 1;
}
if (locatorbased && (locatorservice == ST_MAX)) {
errprintf("Must specify --service when using locator\n");
return 1;
}
if (!locatorbased && (rbtBegin(peers) == rbtEnd(peers))) {
errprintf("Must specify command for local worker\n");
return 1;
}
/* Do cache responses to avoid doing too many lookups */
if (locatorbased) locator_prepcache(locatorservice, 0);
/* Go daemon */
if (daemonize) {
/* Become a daemon */
pid_t daemonpid = fork();
if (daemonpid < 0) {
/* Fork failed */
errprintf("Could not fork child\n");
exit(1);
}
else if (daemonpid > 0) {
/* Parent creates PID file and exits */
FILE *fd = NULL;
if (pidfile) fd = fopen(pidfile, "w");
if (fd) {
fprintf(fd, "%d\n", (int)daemonpid);
fclose(fd);
}
exit(0);
}
/* Child (daemon) continues here */
setsid();
}
/* Catch signals */
setup_signalhandler("xymond_channel");
memset(&sa, 0, sizeof(sa));
sa.sa_handler = sig_handler;
sigaction(SIGINT, &sa, NULL);
sigaction(SIGTERM, &sa, NULL);
sigaction(SIGCHLD, &sa, NULL);
signal(SIGALRM, SIG_IGN);
/* Switch stdout/stderr to the logfile, if one was specified */
freopen("/dev/null", "r", stdin); /* xymond_channel's stdin is not used */
if (logfn) {
freopen(logfn, "a", stdout);
freopen(logfn, "a", stderr);
}
/* Attach to the channel */
channel = setup_channel(cnid, CHAN_CLIENT);
if (channel == NULL) {
errprintf("Channel not available\n");
running = 0;
}
while (running) {
/*
* Wait for GOCLIENT to go up.
*
* Note that we use IPC_NOWAIT if there are messages in the
* queue, because then we just want to pick up a message if
* there is one, and if not we want to continue pushing the
* queued data to the worker.
*/
struct sembuf s;
int n;
s.sem_num = GOCLIENT; s.sem_op = -1; s.sem_flg = ((pendingcount > 0) ? IPC_NOWAIT : 0);
n = semop(channel->semid, &s, 1);
if (n == 0) {
/*
* GOCLIENT went high, and so we got alerted about a new
* message arriving. Copy the message to our own buffer queue.
*/
char *inbuf = NULL;
if (!msgfilter || matchregex(channel->channelbuf, msgfilter) || matchregex(channel->channelbuf, stdfilter)) {
inbuf = strdup(channel->channelbuf);
}
/*
* Now we have safely stored the new message in our buffer.
* Wait until any other clients on the same channel have picked up
* this message (GOCLIENT reaches 0).
*
* We wrap this into an alarm handler, because it can occasionally
* fail, causing the whole system to lock up. We dont want that....
* We'll set the alarm to trigger after 1 second. Experience shows
* that we'll either succeed in a few milliseconds, or fail completely
* and wait the full alarm-timer duration.
*/
gotalarm = 0; signal(SIGALRM, sig_handler); alarm(2);
do {
s.sem_num = GOCLIENT; s.sem_op = 0; s.sem_flg = 0;
n = semop(channel->semid, &s, 1);
} while ((n == -1) && (errno == EAGAIN) && running && (!gotalarm));
signal(SIGALRM, SIG_IGN);
if (gotalarm) {
errprintf("Gave up waiting for GOCLIENT to go low.\n");
}
/*
* Let master know we got it by downing BOARDBUSY.
* This should not block, since BOARDBUSY is upped
* by the master just before he ups GOCLIENT.
*/
do {
s.sem_num = BOARDBUSY; s.sem_op = -1; s.sem_flg = IPC_NOWAIT;
n = semop(channel->semid, &s, 1);
} while ((n == -1) && (errno == EINTR));
if (n == -1) {
errprintf("Tried to down BOARDBUSY: %s\n", strerror(errno));
}
if (inbuf) {
/*
* See if they want us to rotate logs. We pass this on to
* the worker module as well, but must handle our own logfile.
*/
if (strncmp(inbuf, "@@logrotate", 11) == 0) {
freopen(logfn, "a", stdout);
freopen(logfn, "a", stderr);
}
/*
* Put the new message on our outbound queue.
*/
if (addmessage(inbuf) != 0) {
/* Failed to queue message, free the buffer */
xfree(inbuf);
}
}
}
else {
if (errno != EAGAIN) {
dbgprintf("Semaphore wait aborted: %s\n", strerror(errno));
continue;
}
}
/*
* We've picked up messages from the master. Now we
* must push them to the worker process. Since there
* is no way to hang off both a semaphore and select(),
* we'll just push as much data as possible into the
* pipe. If we get to a point where we would block,
* then wait a teeny bit of time and restart the
* whole loop with checking for new messages from the
* master etc.
*
* In theory, this could become an almost busy-wait loop.
* In practice, however, the queue will be empty most
* of the time because we'll just shove the data to the
* worker child.
*/
for (handle = rbtBegin(peers); (handle != rbtEnd(peers)); handle = rbtNext(peers, handle)) {
int canwrite = 1, hasfailed = 0;
xymon_peer_t *pwalk;
time_t msgtimeout = gettimer() - MSGTIMEOUT;
int flushcount = 0;
pwalk = (xymon_peer_t *) gettreeitem(peers, handle);
if (pwalk->msghead == NULL) continue; /* Ignore peers with nothing queued */
switch (pwalk->peerstatus) {
case P_UP:
canwrite = 1;
break;
case P_DOWN:
openconnection(pwalk);
canwrite = (pwalk->peerstatus == P_UP);
break;
case P_FAILED:
canwrite = 0;
break;
}
/* See if we have stale messages queued */
while (pwalk->msghead && (pwalk->msghead->tstamp < msgtimeout)) {
flushmessage(pwalk);
flushcount++;
}
if (flushcount) {
errprintf("Flushed %d stale messages for %s:%d\n",
flushcount,
inet_ntoa(pwalk->peeraddr.sin_addr),
ntohs(pwalk->peeraddr.sin_port));
}
while (pwalk->msghead && canwrite) {
fd_set fdwrite;
struct timeval tmo;
/* Check that this peer is ready for writing. */
FD_ZERO(&fdwrite); FD_SET(pwalk->peersocket, &fdwrite);
tmo.tv_sec = 0; tmo.tv_usec = 2000;
n = select(pwalk->peersocket+1, NULL, &fdwrite, NULL, &tmo);
if (n == -1) {
errprintf("select() failed: %s\n", strerror(errno));
canwrite = 0;
hasfailed = 1;
continue;
}
else if ((n == 0) || (!FD_ISSET(pwalk->peersocket, &fdwrite))) {
canwrite = 0;
continue;
}
n = write(pwalk->peersocket, pwalk->msghead->bufp, pwalk->msghead->buflen);
if (n >= 0) {
pwalk->msghead->bufp += n;
pwalk->msghead->buflen -= n;
if (pwalk->msghead->buflen == 0) flushmessage(pwalk);
}
else if (errno == EAGAIN) {
/*
* Write would block ... stop for now.
*/
canwrite = 0;
}
else {
hasfailed = 1;
}
if (hasfailed) {
/* Write failed, or message grew stale */
errprintf("Peer at %s:%d failed: %s\n",
inet_ntoa(pwalk->peeraddr.sin_addr), ntohs(pwalk->peeraddr.sin_port),
strerror(errno));
canwrite = 0;
shutdownconnection(pwalk);
if (pwalk->peertype == P_NET) locator_serverdown(pwalk->peername, locatorservice);
pwalk->peerstatus = P_FAILED;
}
}
}
}
/* Detach from channels */
close_channel(channel, CHAN_CLIENT);
/* Close peer connections */
for (handle = rbtBegin(peers); (handle != rbtEnd(peers)); handle = rbtNext(peers, handle)) {
xymon_peer_t *pwalk = (xymon_peer_t *) gettreeitem(peers, handle);
shutdownconnection(pwalk);
}
/* Remove the PID file */
if (pidfile) unlink(pidfile);
return 0;
}