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[paraslash.git] / http_send.c
1 /* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
2
3 /** \file http_send.c paraslash's http sender */
4
5 #include <netinet/in.h>
6 #include <sys/socket.h>
7 #include <regex.h>
8 #include <sys/types.h>
9 #include <arpa/inet.h>
10 #include <sys/un.h>
11 #include <netdb.h>
12 #include <lopsub.h>
13
14 #include "server.lsg.h"
15 #include "para.h"
16 #include "error.h"
17 #include "string.h"
18 #include "afh.h"
19 #include "net.h"
20 #include "server.h"
21 #include "http.h"
22 #include "list.h"
23 #include "send.h"
24 #include "sched.h"
25 #include "vss.h"
26 #include "close_on_fork.h"
27 #include "fd.h"
28 #include "chunk_queue.h"
29
30 /** Message sent to clients that do not send a valid get request. */
31 #define HTTP_ERR_MSG "HTTP/1.0 400 Bad Request\n"
32
33 /** The possible states of a client from the server's POV. */
34 enum http_client_status {
35 /** We accepted the connection on the tcp socket. */
36 HTTP_CONNECTED,
37 /** Successfully received the get request. */
38 HTTP_GOT_GET_REQUEST,
39 /** Connection is ready for sending audio data. */
40 HTTP_STREAMING,
41 /** We didn't receive a valid get request. */
42 HTTP_INVALID_GET_REQUEST
43 };
44
45 /** For each connected client, a structure of this type is maintained. */
46 struct private_http_sender_data {
47 /** The current state of this client. */
48 enum http_client_status status;
49 };
50
51 static struct sender_status http_sender_status, *hss = &http_sender_status;
52
53 static int http_send_msg(struct sender_client *sc, const char *msg)
54 {
55 int ret = write_buffer(sc->fd, msg);
56
57 if (ret < 0)
58 shutdown_client(sc, hss);
59 return ret;
60 }
61
62 static void http_send_ok_msg(struct sender_client *sc)
63 {
64 PARA_INFO_LOG("sending http ok message to fd %d\n", sc->fd);
65 http_send_msg(sc, HTTP_OK_MSG);
66 }
67
68 static int http_send_err_msg(struct sender_client *sc)
69 {
70 PARA_NOTICE_LOG("sending bad request message to fd %d\n", sc->fd);
71 return http_send_msg(sc, HTTP_ERR_MSG);
72 }
73
74 static void http_shutdown_clients(void)
75 {
76 shutdown_clients(hss);
77 }
78
79 static void http_shutdown(void)
80 {
81 http_shutdown_clients();
82 generic_acl_deplete(&hss->acl);
83 }
84
85 static int queue_chunk_or_shutdown(struct sender_client *sc,
86 struct sender_status *ss, const char *buf, size_t num_bytes)
87 {
88 int ret = cq_enqueue(sc->cq, buf, num_bytes);
89 if (ret < 0)
90 shutdown_client(sc, ss);
91 return ret;
92 }
93
94 /**
95 * Send one chunk of audio data to a connected client.
96 *
97 * \param sc The client.
98 * \param ss The sender.
99 * \param current_chunk The number of the chunk to write.
100 * \param buf The data to write.
101 * \param len The number of bytes of \a buf.
102 * \param header_buf The audio file header.
103 * \param header_len The number of bytes of \a header_buf.
104 *
105 * On errors, the client is shut down. If only a part of the buffer could be
106 * written, the remainder is put into the chunk queue for that client.
107 */
108 static void http_send_chunk(struct sender_client *sc, struct sender_status *ss,
109 long unsigned current_chunk, const char *buf, size_t len,
110 const char *header_buf, size_t header_len)
111 {
112 int ret;
113
114 if (!sc->header_sent && current_chunk) {
115 if (header_buf && header_len > 0) {
116 ret = queue_chunk_or_shutdown(sc, ss, header_buf, header_len);
117 if (ret < 0)
118 goto out;
119 }
120 }
121 sc->header_sent = 1;
122 ret = send_queued_chunks(sc->fd, sc->cq);
123 if (ret < 0) {
124 shutdown_client(sc, ss);
125 goto out;
126 }
127 if (!len)
128 goto out;
129 if (!ret) { /* still data left in the queue */
130 ret = queue_chunk_or_shutdown(sc, ss, buf, len);
131 goto out;
132 }
133 ret = xwrite(sc->fd, buf, len);
134 if (ret < 0) {
135 shutdown_client(sc, ss);
136 goto out;
137 }
138 if (ret != len)
139 ret = queue_chunk_or_shutdown(sc, ss, buf + ret, len - ret);
140 out:
141 if (ret < 0)
142 PARA_NOTICE_LOG("%s\n", para_strerror(-ret));
143 }
144
145 static void http_send(long unsigned current_chunk,
146 __a_unused long unsigned chunks_sent, const char *buf, size_t len,
147 const char *header_buf, size_t header_len)
148 {
149 struct sender_client *sc, *tmp;
150
151 list_for_each_entry_safe(sc, tmp, &hss->client_list, node) {
152 struct private_http_sender_data *phsd = sc->private_data;
153
154 if (phsd->status == HTTP_STREAMING)
155 http_send_chunk(sc, hss, current_chunk, buf, len,
156 header_buf, header_len);
157 }
158 }
159
160 static void http_post_select(fd_set *rfds, __a_unused fd_set *wfds)
161 {
162 struct sender_client *sc, *tmp;
163 struct private_http_sender_data *phsd;
164 int ret;
165
166 list_for_each_entry_safe(sc, tmp, &hss->client_list, node) {
167 phsd = sc->private_data;
168 switch (phsd->status) {
169 case HTTP_STREAMING: /* nothing to do */
170 break;
171 case HTTP_CONNECTED: /* need to recv get request */
172 ret = read_pattern(sc->fd, HTTP_GET_MSG, MAXLINE, rfds);
173 if (ret < 0)
174 phsd->status = HTTP_INVALID_GET_REQUEST;
175 else if (ret > 0) {
176 phsd->status = HTTP_GOT_GET_REQUEST;
177 PARA_INFO_LOG("received get request\n");
178 }
179 break;
180 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
181 phsd->status = HTTP_STREAMING;
182 http_send_ok_msg(sc);
183 break;
184 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
185 if (http_send_err_msg(sc) >= 0)
186 shutdown_client(sc, hss);
187 break;
188 }
189 }
190 sc = accept_sender_client(hss, rfds);
191 if (!sc)
192 return;
193 phsd = para_malloc(sizeof(*phsd));
194 sc->private_data = phsd;
195 phsd->status = HTTP_CONNECTED;
196 }
197
198 static void http_pre_select(int *max_fileno, fd_set *rfds, fd_set *wfds)
199 {
200 struct sender_client *sc, *tmp;
201 unsigned n;
202
203 FOR_EACH_LISTEN_FD(n, hss) {
204 if (hss->listen_fds[n] < 0)
205 continue;
206 para_fd_set(hss->listen_fds[n], rfds, max_fileno);
207 }
208 list_for_each_entry_safe(sc, tmp, &hss->client_list, node) {
209 struct private_http_sender_data *phsd = sc->private_data;
210 if (phsd->status == HTTP_CONNECTED) /* need to recv get request */
211 para_fd_set(sc->fd, rfds, max_fileno);
212 if (phsd->status == HTTP_GOT_GET_REQUEST ||
213 phsd->status == HTTP_INVALID_GET_REQUEST)
214 para_fd_set(sc->fd, wfds, max_fileno);
215 }
216 }
217
218 static int http_com_on(__a_unused struct sender_command_data *scd)
219 {
220 generic_com_on(hss, IPPROTO_TCP);
221 return 1;
222 }
223
224 static int http_com_off(__a_unused struct sender_command_data *scd)
225 {
226 generic_com_off(hss);
227 return 1;
228 }
229
230 static int http_com_deny(struct sender_command_data *scd)
231 {
232 generic_com_deny(scd, hss);
233 return 1;
234 }
235
236 static int http_com_allow(struct sender_command_data *scd)
237 {
238 generic_com_allow(scd, hss);
239 return 1;
240 }
241
242 static char *http_status(void)
243 {
244 return generic_sender_status(hss, "http");
245 }
246
247 /*
248 * Initialize the client list and the access control list, and optionally
249 * listen on the tcp port.
250 */
251 static void http_send_init(void)
252 {
253 init_sender_status(hss, OPT_RESULT(HTTP_ACCESS),
254 OPT_RESULT(HTTP_LISTEN_ADDRESS),
255 OPT_UINT32_VAL(HTTP_PORT), OPT_UINT32_VAL(HTTP_MAX_CLIENTS),
256 OPT_GIVEN(HTTP_DEFAULT_DENY));
257 if (OPT_GIVEN(HTTP_NO_AUTOSTART))
258 return;
259 generic_com_on(hss, IPPROTO_TCP);
260 }
261
262 /**
263 * The HTTP sender.
264 *
265 * This is the only sender which does not FEC-encode the stream. This is not
266 * necessary because HTTP sits on top of TCP, a reliable transport which
267 * retransmits lost packets automatically. The sender employs per-client queues
268 * which queue chunks of audio data if they can not be sent immediately because
269 * the write operation would block. Most methods of the sender are implemented
270 * as wrappers for the generic functions defined in \ref send_common.c.
271 */
272 const struct sender http_sender = {
273 .name = "http",
274 .init = http_send_init,
275 .shutdown = http_shutdown,
276 .pre_select = http_pre_select,
277 .post_select = http_post_select,
278 .send = http_send,
279 .shutdown_clients = http_shutdown_clients,
280 .client_cmds = {
281 [SENDER_on] = http_com_on,
282 [SENDER_off] = http_com_off,
283 [SENDER_deny] = http_com_deny,
284 [SENDER_allow] = http_com_allow,
285 },
286 .help = generic_sender_help,
287 .status = http_status,
288 };