c506fd96f15c222386fc14b5c7a0d74462e31f4e
[paraslash.git] / dccp_send.c
1 /*
2 * Copyright (C) 2006-2007 Andre Noll <maan@systemlinux.org>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6
7 /** \file dccp_send.c paraslash's dccp sender */
8
9 /*
10 * based on server.c of dccp-cs-0.01.tar.bz2,
11 * (C) 2005 Ian McDonald <imcdnzl@gmail.com>
12 */
13
14 #include <sys/types.h>
15 #include <dirent.h>
16
17 #include "para.h"
18 #include "error.h"
19 #include "afh.h"
20 #include "server.h"
21 #include "net.h"
22 #include "list.h"
23 #include "vss.h"
24 #include "send.h"
25 #include "dccp.h"
26 #include "string.h"
27 #include "fd.h"
28 #include "close_on_fork.h"
29 #include "chunk_queue.h"
30 #include "server.cmdline.h"
31
32 /** the list of connected clients **/
33 static struct list_head clients;
34 static int listen_fd = -1;
35 static struct sender *self;
36
37 /** Maximal number of bytes in a chunk queue. */
38 #define DCCP_MAX_PENDING_BYTES 40000
39
40 /** describes one connected client */
41 struct dccp_client {
42 /** the dccp socket */
43 int fd;
44 /** address information about the client */
45 struct sockaddr_in addr;
46 /** the position of this client in the client list */
47 struct list_head node;
48 /** non-zero if audio file header has been sent */
49 int header_sent;
50 /** The list of pending chunks for this client. */
51 struct chunk_queue *cq;
52 };
53
54 static void dccp_pre_select( int *max_fileno, fd_set *rfds,
55 __a_unused fd_set *wfds)
56 {
57 if (listen_fd < 0)
58 return;
59 FD_SET(listen_fd, rfds);
60 *max_fileno = PARA_MAX(*max_fileno, listen_fd);
61 }
62
63 static void dccp_post_select(fd_set *rfds, __a_unused fd_set *wfds)
64 {
65 struct dccp_client *dc;
66 int ret;
67
68 if (!FD_ISSET(listen_fd, rfds))
69 return;
70 dc = para_calloc(sizeof(struct dccp_client));
71 ret = para_accept(listen_fd, &dc->addr, sizeof(struct sockaddr_in));
72 if (ret < 0) {
73 PARA_ERROR_LOG("%s\n", PARA_STRERROR(-ret));
74 return;
75 }
76 PARA_NOTICE_LOG("connection from %s\n", inet_ntoa(dc->addr.sin_addr));
77 dc->fd = ret;
78 para_list_add(&dc->node, &clients);
79 add_close_on_fork_list(dc->fd);
80 mark_fd_nonblock(dc->fd);
81 dc->cq = cq_new(DCCP_MAX_PENDING_BYTES);
82 }
83
84 static int dccp_open(void)
85 {
86 struct sockaddr_in servaddr;
87 int ret;
88
89 ret = dccp_get_socket();
90 if (ret < 0)
91 return ret;
92 listen_fd = ret;
93
94 memset(&servaddr, 0, sizeof(servaddr));
95 servaddr.sin_family = AF_INET;
96 servaddr.sin_addr.s_addr = htonl(INADDR_ANY);
97 servaddr.sin_port = htons(conf.dccp_port_arg);
98 ret = bind(listen_fd, (struct sockaddr *)&servaddr, sizeof(servaddr));
99 if (ret < 0)
100 return -E_DCCP_BIND;
101 ret = dccp_set_socket(listen_fd);
102 if (ret < 0)
103 return ret;
104 ret = listen(listen_fd, 0);
105 if (ret < 0) {
106 PARA_ERROR_LOG("%s\n", strerror(errno));
107 return -E_DCCP_LISTEN;
108 }
109 PARA_DEBUG_LOG("listening on fd %d\n", listen_fd);
110 add_close_on_fork_list(listen_fd);
111 mark_fd_nonblock(listen_fd);
112 return 1;
113 }
114
115 static void dccp_shutdown_client(struct dccp_client *dc)
116 {
117 PARA_DEBUG_LOG("shutting down %s (fd %d)\n", inet_ntoa(dc->addr.sin_addr),
118 dc->fd);
119 close(dc->fd);
120 del_close_on_fork_list(dc->fd);
121 cq_destroy(dc->cq);
122 list_del(&dc->node);
123 free(dc);
124 }
125
126 /*
127 * ret: Negative on errors, zero if nothing was written and write returned
128 * EAGAIN, number of bytes written else.
129 */
130 static int dccp_write(int fd, const char *buf, size_t len)
131 {
132 size_t written = 0;
133 int ret = 0;
134
135 while (written < len) {
136 ret = write(fd, buf + written, PARA_MIN(1024, len - written));
137 /*
138 * Error handling: CCID3 has a sending wait queue which fills up and is
139 * emptied asynchronously. The EAGAIN case means that there is currently
140 * no space in the wait queue, but this can change at any moment and is
141 * thus not an error condition.
142 */
143 if (ret < 0 && errno == EAGAIN)
144 return written;
145 if (ret < 0) {
146 PARA_ERROR_LOG("%s\n", strerror(errno));
147 return -E_DCCP_WRITE;
148 }
149 written += ret;
150 }
151 return written;
152 }
153
154 static int queue_chunk_or_shutdown(struct dccp_client *dc, long unsigned chunk_num,
155 size_t sent)
156 {
157 int ret = cq_enqueue(dc->cq, chunk_num, sent);
158 if (ret < 0) {
159 PARA_NOTICE_LOG("enqueue error\n");
160 dccp_shutdown_client(dc);
161 }
162 return ret;
163 }
164
165 static int send_queued_chunks(struct dccp_client *dc)
166 {
167 struct queued_chunk *qc;
168 while ((qc = cq_peek(dc->cq))) {
169 char *buf;
170 size_t len;
171 int ret;
172 cq_get(qc, &buf, &len);
173 ret = dccp_write(dc->fd, buf, len);
174 if (ret < 0)
175 return ret;
176 cq_update(dc->cq, ret);
177 if (ret != len)
178 return 1;
179 cq_dequeue(dc->cq);
180 }
181 return 1;
182 }
183
184 static void dccp_send(long unsigned current_chunk,
185 __a_unused long unsigned chunks_sent, const char *buf, size_t len)
186 {
187 struct dccp_client *dc, *tmp;
188 int ret;
189 char *header_buf;
190 size_t header_len;
191
192 if (listen_fd < 0 || !len)
193 return;
194
195 list_for_each_entry_safe(dc, tmp, &clients, node) {
196 if (!dc->header_sent && current_chunk) {
197 header_buf = vss_get_header(&header_len);
198 if (header_buf && header_len > 0) {
199 if (queue_chunk_or_shutdown(dc, -1U, 0) < 0)
200 continue;
201 }
202 dc->header_sent = 1;
203 }
204 ret = send_queued_chunks(dc);
205 if (ret < 0) {
206 dccp_shutdown_client(dc);
207 continue;
208 }
209 // PARA_DEBUG_LOG("writing %d bytes to fd %d\n", len, dc->fd);
210 ret = dccp_write(dc->fd, buf, len);
211 if (ret < 0) {
212 PARA_NOTICE_LOG("%s\n", PARA_STRERROR(-ret));
213 dccp_shutdown_client(dc);
214 continue;
215 }
216 if (ret != len)
217 queue_chunk_or_shutdown(dc, current_chunk, ret);
218 }
219 }
220
221 static void dccp_shutdown_clients(void)
222 {
223 struct dccp_client *dc, *tmp;
224
225 list_for_each_entry_safe(dc, tmp, &clients, node)
226 dccp_shutdown_client(dc);
227 }
228
229 static char *dccp_info(void)
230 {
231 static char *buf;
232 int num_clients = 0;
233 struct dccp_client *dc, *tmp;
234
235 free(buf);
236 list_for_each_entry_safe(dc, tmp, &clients, node)
237 num_clients++;
238 buf = make_message("dccp connected clients: %d\n", num_clients);
239 return buf;
240 }
241
242 static char *dccp_help(void)
243 {
244 return make_message("no help available\n");
245 }
246
247 /**
248 * the init function of the dccp sender
249 *
250 * \param s pointer to the dccp sender struct
251 *
252 * It initializes all function pointers of \a s and starts
253 * listening on the given port.
254 */
255 void dccp_send_init(struct sender *s)
256 {
257 int ret;
258
259 INIT_LIST_HEAD(&clients);
260 s->info = dccp_info;
261 s->send = dccp_send;
262 s->pre_select = dccp_pre_select;
263 s->post_select = dccp_post_select;
264 s->shutdown_clients = dccp_shutdown_clients;
265 s->help = dccp_help;
266 s->client_cmds[SENDER_ON] = NULL;
267 s->client_cmds[SENDER_OFF] = NULL;
268 s->client_cmds[SENDER_DENY] = NULL;
269 s->client_cmds[SENDER_ALLOW] = NULL;
270 s->client_cmds[SENDER_ADD] = NULL;
271 s->client_cmds[SENDER_DELETE] = NULL;
272 self = s;
273 ret = dccp_open();
274 if (ret < 0) {
275 PARA_ERROR_LOG("%s\n", PARA_STRERROR(-ret));
276 s->status = SENDER_OFF;
277 } else
278 s->status = SENDER_ON;
279 }