{http,dccp}_send.c: Kill unused variable "self".
[paraslash.git] / dccp_send.c
1 /*
2 * Copyright (C) 2006-2008 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 "string.h"
20 #include "afh.h"
21 #include "afs.h"
22 #include "server.h"
23 #include "net.h"
24 #include "list.h"
25 #include "vss.h"
26 #include "send.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
36 /** Maximal number of bytes in a chunk queue. */
37 #define DCCP_MAX_PENDING_BYTES 40000
38
39 /** describes one connected client */
40 struct dccp_client {
41 /** the dccp socket */
42 int fd;
43 /** The socket `name' of the client. */
44 char *name;
45 /** the position of this client in the client list */
46 struct list_head node;
47 /** non-zero if audio file header has been sent */
48 int header_sent;
49 /** The list of pending chunks for this client. */
50 struct chunk_queue *cq;
51 };
52
53 static void dccp_pre_select(int *max_fileno, fd_set *rfds,
54 __a_unused fd_set *wfds)
55 {
56 if (listen_fd < 0)
57 return;
58 FD_SET(listen_fd, rfds);
59 *max_fileno = PARA_MAX(*max_fileno, listen_fd);
60 }
61
62 static void dccp_post_select(fd_set *rfds, __a_unused fd_set *wfds)
63 {
64 struct dccp_client *dc;
65 int ret, fd;
66
67 if (listen_fd < 0 || !FD_ISSET(listen_fd, rfds))
68 return;
69 ret = para_accept(listen_fd, NULL, 0);
70 if (ret < 0) {
71 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
72 return;
73 }
74 fd = ret;
75 /*
76 * Bypass unused CCID paths: the sender does not receive application data
77 * from the client; by shutting down this unused communication path we can
78 * reduce processing costs a bit. See analogous comment in dccp_recv.c.
79 */
80 if (shutdown(fd, SHUT_RD) < 0) {
81 PARA_ERROR_LOG("shutdown(SHUT_RD): %s\n", strerror(errno));
82 goto err;
83 }
84 ret = mark_fd_nonblocking(fd);
85 if (ret < 0) {
86 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
87 goto err;
88 }
89 dc = para_calloc(sizeof(struct dccp_client));
90 dc->fd = fd;
91 dc->name = make_message("%s", remote_name(dc->fd));
92 PARA_NOTICE_LOG("connection from %s\n", dc->name);
93 para_list_add(&dc->node, &clients);
94 add_close_on_fork_list(dc->fd);
95 dc->cq = cq_new(DCCP_MAX_PENDING_BYTES);
96 return;
97 err:
98 close(fd);
99 }
100
101 static int dccp_open(void)
102 {
103 int ret = para_listen(AF_UNSPEC, IPPROTO_DCCP, conf.dccp_port_arg);
104
105 if (ret < 0)
106 return ret;
107 listen_fd = ret;
108 ret = mark_fd_nonblocking(listen_fd);
109 if (ret < 0) {
110 PARA_EMERG_LOG("%s\n", para_strerror(-ret));
111 exit(EXIT_FAILURE);
112 }
113 add_close_on_fork_list(listen_fd);
114 return 1;
115 }
116
117 static void dccp_shutdown_client(struct dccp_client *dc)
118 {
119 PARA_DEBUG_LOG("shutting down %s (fd %d)\n", dc->name, dc->fd);
120 free(dc->name);
121 close(dc->fd);
122 del_close_on_fork_list(dc->fd);
123 cq_destroy(dc->cq);
124 list_del(&dc->node);
125 free(dc);
126 }
127
128 /*
129 * ret: Negative on errors, zero if nothing was written and write returned
130 * EAGAIN, number of bytes written else.
131 */
132 static int dccp_write(int fd, const char *buf, size_t len)
133 {
134 size_t written = 0;
135 int ret = 0;
136
137 while (written < len) {
138 ret = write(fd, buf + written, PARA_MIN(1024, len - written));
139 /*
140 * Error handling: CCID3 has a sending wait queue which fills
141 * up and is emptied asynchronously. The EAGAIN case means that
142 * there is currently no space in the wait queue, but this can
143 * change at any moment and is thus not an error condition.
144 */
145 if (ret < 0 && errno == EAGAIN)
146 return written;
147 if (ret < 0)
148 return -ERRNO_TO_PARA_ERROR(errno);
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
191 list_for_each_entry_safe(dc, tmp, &clients, node) {
192 if (!dc->header_sent && current_chunk) {
193 size_t header_len;
194 header_buf = vss_get_header(&header_len);
195 if (header_buf && header_len > 0) {
196 if (queue_chunk_or_shutdown(dc, -1U, 0) < 0)
197 continue;
198 }
199 dc->header_sent = 1;
200 }
201 ret = send_queued_chunks(dc);
202 if (ret < 0) {
203 dccp_shutdown_client(dc);
204 continue;
205 }
206 if (!len)
207 continue;
208 // PARA_DEBUG_LOG("writing %d bytes to fd %d\n", len, dc->fd);
209 ret = dccp_write(dc->fd, buf, len);
210 if (ret < 0) {
211 PARA_NOTICE_LOG("%s\n", para_strerror(-ret));
212 dccp_shutdown_client(dc);
213 continue;
214 }
215 if (ret != len)
216 queue_chunk_or_shutdown(dc, current_chunk, ret);
217 }
218 }
219
220 static void dccp_shutdown_clients(void)
221 {
222 struct dccp_client *dc, *tmp;
223
224 list_for_each_entry_safe(dc, tmp, &clients, node)
225 dccp_shutdown_client(dc);
226 }
227
228 static char *dccp_info(void)
229 {
230 static char *buf;
231 int num_clients = 0;
232 struct dccp_client *dc, *tmp;
233
234 free(buf);
235 list_for_each_entry_safe(dc, tmp, &clients, node)
236 num_clients++;
237 buf = make_message("dccp connected clients: %d\n", num_clients);
238 return buf;
239 }
240
241 static char *dccp_help(void)
242 {
243 return make_message("no help available\n");
244 }
245
246 /**
247 * the init function of the dccp sender
248 *
249 * \param s pointer to the dccp sender struct
250 *
251 * It initializes all function pointers of \a s and starts
252 * listening on the given port.
253 */
254 void dccp_send_init(struct sender *s)
255 {
256 int ret;
257
258 INIT_LIST_HEAD(&clients);
259 s->info = dccp_info;
260 s->send = dccp_send;
261 s->pre_select = dccp_pre_select;
262 s->post_select = dccp_post_select;
263 s->shutdown_clients = dccp_shutdown_clients;
264 s->help = dccp_help;
265 s->client_cmds[SENDER_ON] = NULL;
266 s->client_cmds[SENDER_OFF] = NULL;
267 s->client_cmds[SENDER_DENY] = NULL;
268 s->client_cmds[SENDER_ALLOW] = NULL;
269 s->client_cmds[SENDER_ADD] = NULL;
270 s->client_cmds[SENDER_DELETE] = NULL;
271 ret = dccp_open();
272 if (ret < 0)
273 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
274 }