1 #include <ccan/oserver/oserver.h>
2 #include <ccan/oserver/oserver_types.h>
3 #include <ccan/oserver/oserver_cdump.h>
4 #include <ccan/read_write_all/read_write_all.h>
5 #include <ccan/opt/opt.h>
6 #include <ccan/tevent/tevent.h>
7 #include <ccan/array_size/array_size.h>
8 #include <ccan/grab_file/grab_file.h>
10 #include <sys/socket.h>
11 #include <netinet/in.h>
12 #include <netinet/tcp.h>
22 #include <sys/types.h>
26 static uint16_t state_flag_map[] = {
27 [SENDING_GREETING] = TEVENT_FD_WRITE,
28 [RECEIVING_USER_QUESTION] = TEVENT_FD_READ,
29 [SENDING_OTHER_QUESTION_PREFIX] = TEVENT_FD_WRITE,
30 [SENDING_OTHER_QUESTION] = TEVENT_FD_WRITE,
31 [RECEIVING_OTHER_ANSWER] = TEVENT_FD_READ,
32 [SENDING_ANSWER_PREFIX] = TEVENT_FD_WRITE,
33 [SENDING_ANSWER] = TEVENT_FD_WRITE,
37 static ssize_t write_string(int fd, const char *str)
39 return write(fd, str, strlen(str));
42 static ssize_t read_string(int fd, char **buf)
44 ssize_t ret, len, maxlen;
47 maxlen = talloc_array_length(*buf);
49 if (maxlen < len + 100) {
51 *buf = talloc_realloc(NULL, *buf, char, maxlen);
54 ret = read(fd, *buf + len, maxlen - len - 1);
56 (*buf)[len + ret] = '\0';
60 static bool input_finished(const char *str)
62 return strchr(str, '\n');
65 /* Update state, and set our READ/WRITE flags appropriately. */
66 static void set_state(struct client *c, enum state state)
69 tevent_fd_set_flags(c->fde, state_flag_map[state]);
72 /* Returns false on error, increments state on finishing string. */
73 static bool send_string(struct client *c, const char *str)
75 ssize_t len = write_string(c->fd, str + c->bytes_sent);
79 if (c->bytes_sent == strlen(str)) {
81 set_state(c, c->state+1);
86 static bool get_subclient(struct client *me)
90 for (i = 0; i < ARRAY_SIZE(me->oserver->clients); i++) {
91 struct client *c = me->oserver->clients[i];
94 if (c->oracle == -1 && input_finished(c->question)) {
95 me->subclient = c->id;
103 static bool get_oracle(struct client *me)
107 for (i = 0; i < ARRAY_SIZE(me->oserver->clients); i++) {
108 struct client *c = me->oserver->clients[i];
111 if (c->subclient == -1 && input_finished(c->question)) {
113 c->subclient = me->id;
120 static void wakeup(struct client *c)
122 tevent_fd_set_flags(c->fde, state_flag_map[c->state]);
125 static void service_client(struct tevent_context *ev,
126 struct tevent_fd *fde, uint16_t flags, void *_c)
128 struct client *c = _c;
132 case SENDING_GREETING:
133 if (!send_string(c, "Welcome. Please ask your question.\n"))
136 case RECEIVING_USER_QUESTION:
137 len = read_string(c->fd, &c->question);
140 if (input_finished(c->question))
141 set_state(c, SENDING_OTHER_QUESTION_PREFIX);
143 case SENDING_OTHER_QUESTION_PREFIX:
144 if (c->subclient == -1)
146 if (!send_string(c, "While the Oracle ponders,"
147 " please answer the following question:\n"))
150 case SENDING_OTHER_QUESTION:
151 if (c->subclient == -1)
154 c->oserver->clients[c->subclient]->question))
157 case RECEIVING_OTHER_ANSWER:
158 if (c->subclient == -1)
160 len = read_string(c->fd,
161 &c->oserver->clients[c->subclient]->answer);
164 if (input_finished(c->oserver->clients[c->subclient]->answer)) {
165 set_state(c, SENDING_ANSWER_PREFIX);
166 wakeup(c->oserver->clients[c->subclient]);
169 case SENDING_ANSWER_PREFIX:
170 if (!input_finished(c->answer))
172 if (!send_string(c, "The Oracle spake thus:\n"))
176 if (!send_string(c, c->answer))
183 if (c->state != FINISHED)
190 if (!get_subclient(c)) {
191 /* We can't get one: go to sleep until someone find_oracle() */
192 tevent_fd_set_flags(c->fde, 0);
194 /* In case they are waiting... */
195 wakeup(c->oserver->clients[c->subclient]);
199 /* If we don't have an oracle and find one, that's OK. */
200 if (c->oracle == -1 && get_oracle(c)) {
201 /* In case they are waiting... */
202 wakeup(c->oserver->clients[c->oracle]);
206 /* Either our oracle is not finished, or we don't have one: sleep. */
207 tevent_fd_set_flags(c->fde, 0);
210 static int cleanup_client(struct client *client)
213 /* We were an oracle? */
214 if (client->subclient >= 0)
215 client->oserver->clients[client->subclient]->oracle = -1;
217 /* We had an oracle? */
218 if (client->oracle >= 0)
219 client->oserver->clients[client->oracle]->subclient = -1;
221 assert(client->oserver->clients[client->id] == client);
222 client->oserver->clients[client->id] = NULL;
226 static void add_client(struct tevent_context *ev,
227 struct tevent_fd *fde, uint16_t flags, void *_oserver)
229 struct oserver *oserver = _oserver;
230 struct client *client;
232 client = talloc(oserver, struct client);
233 client->fd = accept(oserver->fd, NULL, 0);
235 err(1, "Accepting client connection");
237 client->state = SENDING_GREETING;
238 client->bytes_sent = 0;
239 client->question = talloc_strdup(client, "");
240 client->oserver = oserver;
242 client->subclient = -1;
243 client->answer = talloc_strdup(client, "");
244 client->fde = tevent_add_fd(ev, client, client->fd,
245 state_flag_map[client->state],
246 service_client, client);
247 tevent_fd_set_auto_close(client->fde);
249 /* Find empty slot in array for this client. */
250 for (client->id = 0; oserver->clients[client->id]; client->id++);
251 oserver->clients[client->id] = client;
252 talloc_set_destructor(client, cleanup_client);
254 /* Full? Stop listening... */
255 if (client->id == ARRAY_SIZE(oserver->clients)-1)
256 tevent_fd_set_flags(oserver->fde, 0);
259 static void clear_clients(struct oserver *oserver)
261 memset(oserver->clients, 0,
262 ARRAY_SIZE(oserver->clients) * sizeof(oserver->clients[0]));
265 static int destroy_oserver(struct oserver *oserver)
271 static void talloc_dump(struct tevent_context *ev,
272 struct tevent_signal *se,
278 struct oserver *oserver = _oserver;
281 /* Fork off a child for the report, so we aren't stopped. */
283 f = fopen("/var/run/oserver/talloc.dump", "w");
285 talloc_report_full(oserver, f);
292 static void dump(struct tevent_context *ev,
293 struct tevent_signal *se,
299 struct oserver *oserver = _oserver;
303 str = cdump_bundle(ev, cdump_struct_oserver, oserver);
304 fd = open(oserver->dumpfile, O_CREAT|O_TRUNC|O_WRONLY, 0600);
305 write(fd, str, strlen(str));
309 execvp(oserver->argv[0], oserver->argv);
312 static bool load_file(struct oserver *oserver, const char *file)
319 str = grab_file(oserver, file, NULL);
323 if (!cdump_unbundle(oserver, cdump_struct_oserver, oserver, str)) {
331 static bool complete_server(struct tevent_context *ev,
332 struct oserver *oserver, const char *dumpfile)
334 /* Re-set this even if restored from file, in case it changed. */
335 oserver->dumpfile = dumpfile;
336 if (oserver->dumpfile)
337 tevent_add_signal(ev, oserver, SIGHUP, SA_RESTART,
340 /* Don't kill us if client dies. */
341 signal(SIGPIPE, SIG_IGN);
343 /* Show talloc tree on SIGUSR1. */
344 tevent_add_signal(ev, oserver, SIGUSR1, SA_RESTART,
345 talloc_dump, oserver);
347 oserver->fde = tevent_add_fd(ev, oserver, oserver->fd,
348 TEVENT_FD_READ, add_client, oserver);
354 struct oserver *oserver_restore(struct tevent_context *ev, const char *dumpfile)
357 struct oserver *oserver = talloc(ev, struct oserver);
358 if (!load_file(oserver, dumpfile)) {
359 talloc_free(oserver);
363 /* Restore ignored fields in clients, and talloc hierarchy. */
364 for (i = 0; i < ARRAY_SIZE(oserver->clients); i++) {
365 struct client *client = oserver->clients[i];
368 /* These two were marked CDUMP_IGNORE. */
369 client->oserver = oserver;
370 client->fde = tevent_add_fd(ev, client, client->fd,
371 state_flag_map[client->state],
372 service_client, client);
373 tevent_fd_set_auto_close(client->fde);
374 /* cdump knows nothing of talloc. */
375 talloc_steal(oserver, client);
376 talloc_steal(client, client->question);
377 talloc_steal(client, client->answer);
378 talloc_set_destructor(client, cleanup_client);
381 talloc_set_destructor(oserver, destroy_oserver);
382 if (!complete_server(ev, oserver, dumpfile)) {
383 talloc_free(oserver);
389 struct oserver *oserver_setup(struct tevent_context *ev, unsigned short port,
390 const char *dumpfile, char *argv[])
392 struct oserver *oserver;
395 struct sockaddr addr;
396 struct sockaddr_in in;
399 oserver = talloc(ev, struct oserver);
400 oserver->argv = argv;
402 /* Count the terminal NULL in argv_len. */
403 for (oserver->argv_len = 1;
404 argv[oserver->argv_len - 1];
405 oserver->argv_len++);
407 oserver->argv_len = 0;
408 clear_clients(oserver);
409 oserver->fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
410 if (oserver->fd < 0) {
411 talloc_free(oserver);
415 talloc_set_destructor(oserver, destroy_oserver);
417 if (setsockopt(oserver->fd, SOL_SOCKET, SO_REUSEADDR,
419 warn("Setting socket reuse");
421 u.in.sin_family = AF_INET;
422 u.in.sin_port = htons(port);
423 u.in.sin_addr.s_addr = INADDR_ANY;
424 if (bind(oserver->fd, &u.addr, sizeof(u.in)) == -1) {
425 talloc_free(oserver);
429 if (listen(oserver->fd, 0) != 0) {
430 talloc_free(oserver);
434 if (!complete_server(ev, oserver, dumpfile)) {
435 talloc_free(oserver);