1 #include <ccan/oserver/oserver.h>
2 #include <ccan/read_write_all/read_write_all.h>
3 #include <ccan/opt/opt.h>
4 #include <ccan/tevent/tevent.h>
5 #include <ccan/array_size/array_size.h>
7 #include <sys/socket.h>
8 #include <netinet/in.h>
9 #include <netinet/tcp.h>
20 RECEIVING_USER_QUESTION,
25 static uint16_t state_flag_map[] = {
26 [RECEIVING_USER_QUESTION] = TEVENT_FD_READ,
27 [SENDING_ANSWER] = TEVENT_FD_WRITE,
32 /* What are we doing today, brain? */
34 /* Our event info, and the file descriptor. */
35 struct tevent_fd *fde;
37 /* The question we read from client. */
39 /* How many bytes of the reply we sent so far. */
42 struct oserver *oserver;
46 /* 5 clients should be enough for anybody! */
47 struct client *clients[5];
49 struct tevent_fd *fde;
52 static ssize_t write_string(int fd, const char *str)
54 return write(fd, str, strlen(str));
57 static ssize_t read_string(int fd, char **buf)
59 ssize_t ret, len, maxlen;
62 maxlen = talloc_array_length(*buf);
64 if (maxlen < len + 100) {
66 *buf = talloc_realloc(NULL, *buf, char, maxlen);
69 ret = read(fd, *buf + len, maxlen - len - 1);
71 (*buf)[len + ret] = '\0';
75 static bool input_finished(const char *str)
77 return strchr(str, '\n');
80 /* Update state, and set our READ/WRITE flags appropriately. */
81 static void set_state(struct client *c, enum state state)
84 tevent_fd_set_flags(c->fde, state_flag_map[state]);
87 /* Returns false on error, increments state on finishing string. */
88 static bool send_string(struct client *c, const char *str)
90 ssize_t len = write_string(c->fd, str + c->bytes_sent);
94 if (c->bytes_sent == strlen(str)) {
96 set_state(c, c->state+1);
101 static void service_client(struct tevent_context *ev,
102 struct tevent_fd *fde, uint16_t flags, void *_c)
104 struct client *c = _c;
108 case RECEIVING_USER_QUESTION:
109 len = read_string(c->fd, &c->question);
112 if (input_finished(c->question)) {
115 for (i = 0; c->question[i]; i++)
116 c->question[i] = toupper(c->question[i]);
117 set_state(c, SENDING_ANSWER);
121 if (!send_string(c, c->question))
128 if (c->state != FINISHED)
135 static int cleanup_client(struct client *client)
139 for (i = 0; i < ARRAY_SIZE(client->oserver->clients); i++) {
140 if (client->oserver->clients[i] == client) {
141 client->oserver->clients[i] = NULL;
142 tevent_fd_set_flags(client->oserver->fde,
150 static void add_client(struct tevent_context *ev,
151 struct tevent_fd *fde, uint16_t flags, void *_oserver)
153 struct oserver *oserver = _oserver;
154 struct client *client;
157 client = talloc(oserver, struct client);
158 client->fd = accept(oserver->fd, NULL, 0);
160 err(1, "Accepting client connection");
162 client->state = RECEIVING_USER_QUESTION;
163 client->bytes_sent = 0;
164 client->question = talloc_strdup(client, "");
165 client->oserver = oserver;
166 client->fde = tevent_add_fd(ev, client, client->fd,
167 state_flag_map[client->state],
168 service_client, client);
169 tevent_fd_set_auto_close(client->fde);
171 /* Find empty slot in array for this client. */
172 for (i = 0; oserver->clients[i]; i++);
173 oserver->clients[i] = client;
174 talloc_set_destructor(client, cleanup_client);
176 /* Full? Stop listening... */
177 if (i == ARRAY_SIZE(oserver->clients)-1)
178 tevent_fd_set_flags(oserver->fde, 0);
181 static void clear_clients(struct oserver *oserver)
183 memset(oserver->clients, 0,
184 ARRAY_SIZE(oserver->clients) * sizeof(oserver->clients[0]));
187 static int destroy_oserver(struct oserver *oserver)
193 struct oserver *oserver_setup(struct tevent_context *ev, unsigned short port)
195 struct oserver *oserver;
198 struct sockaddr addr;
199 struct sockaddr_in in;
202 oserver = talloc(ev, struct oserver);
203 clear_clients(oserver);
204 oserver->fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
205 if (oserver->fd < 0) {
206 talloc_free(oserver);
210 talloc_set_destructor(oserver, destroy_oserver);
212 if (setsockopt(oserver->fd, SOL_SOCKET, SO_REUSEADDR,
214 warn("Setting socket reuse");
216 u.in.sin_family = AF_INET;
217 u.in.sin_port = htons(port);
218 u.in.sin_addr.s_addr = INADDR_ANY;
219 if (bind(oserver->fd, &u.addr, sizeof(u.in)) == -1) {
220 talloc_free(oserver);
224 if (listen(oserver->fd, 0) != 0) {
225 talloc_free(oserver);
229 oserver->fde = tevent_add_fd(ev, oserver, oserver->fd,
230 TEVENT_FD_READ, add_client, oserver);
232 talloc_free(oserver);
236 /* Don't kill us if client dies. */
237 signal(SIGPIPE, SIG_IGN);