05_DCCP-Remove-Unused.diff
[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 "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 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 /** The socket `name' of the client. */
45 char *name;
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 ret = para_accept(listen_fd, NULL, 0);
71 if (ret < 0) {
72 PARA_ERROR_LOG("%s\n", PARA_STRERROR(-ret));
73 return;
74 }
75 dc = para_calloc(sizeof(struct dccp_client));
76 dc->fd = ret;
77 dc->name = make_message("%s", remote_name(dc->fd));
78 PARA_NOTICE_LOG("connection from %s\n", dc->name);
79 para_list_add(&dc->node, &clients);
80 add_close_on_fork_list(dc->fd);
81 mark_fd_nonblocking(dc->fd);
82 dc->cq = cq_new(DCCP_MAX_PENDING_BYTES);
83 }
84
85 static int dccp_open(void)
86 {
87 int ret = para_listen(AF_UNSPEC, IPPROTO_DCCP, conf.dccp_port_arg);
88
89 if (ret < 0)
90 return ret;
91 listen_fd = ret;
92 add_close_on_fork_list(listen_fd);
93 mark_fd_nonblocking(listen_fd);
94 return 1;
95 }
96
97 static void dccp_shutdown_client(struct dccp_client *dc)
98 {
99 PARA_DEBUG_LOG("shutting down %s (fd %d)\n", dc->name, dc->fd);
100 free(dc->name);
101 close(dc->fd);
102 del_close_on_fork_list(dc->fd);
103 cq_destroy(dc->cq);
104 list_del(&dc->node);
105 free(dc);
106 }
107
108 /*
109 * ret: Negative on errors, zero if nothing was written and write returned
110 * EAGAIN, number of bytes written else.
111 */
112 static int dccp_write(int fd, const char *buf, size_t len)
113 {
114 size_t written = 0;
115 int ret = 0;
116
117 while (written < len) {
118 ret = write(fd, buf + written, PARA_MIN(1024, len - written));
119 /*
120 * Error handling: CCID3 has a sending wait queue which fills up and is
121 * emptied asynchronously. The EAGAIN case means that there is currently
122 * no space in the wait queue, but this can change at any moment and is
123 * thus not an error condition.
124 */
125 if (ret < 0 && errno == EAGAIN)
126 return written;
127 if (ret < 0) {
128 PARA_ERROR_LOG("%s\n", strerror(errno));
129 return -E_DCCP_WRITE;
130 }
131 written += ret;
132 }
133 return written;
134 }
135
136 static int queue_chunk_or_shutdown(struct dccp_client *dc, long unsigned chunk_num,
137 size_t sent)
138 {
139 int ret = cq_enqueue(dc->cq, chunk_num, sent);
140 if (ret < 0) {
141 PARA_NOTICE_LOG("enqueue error\n");
142 dccp_shutdown_client(dc);
143 }
144 return ret;
145 }
146
147 static int send_queued_chunks(struct dccp_client *dc)
148 {
149 struct queued_chunk *qc;
150 while ((qc = cq_peek(dc->cq))) {
151 char *buf;
152 size_t len;
153 int ret;
154 cq_get(qc, &buf, &len);
155 ret = dccp_write(dc->fd, buf, len);
156 if (ret < 0)
157 return ret;
158 cq_update(dc->cq, ret);
159 if (ret != len)
160 return 1;
161 cq_dequeue(dc->cq);
162 }
163 return 1;
164 }
165
166 static void dccp_send(long unsigned current_chunk,
167 __a_unused long unsigned chunks_sent, const char *buf, size_t len)
168 {
169 struct dccp_client *dc, *tmp;
170 int ret;
171 char *header_buf;
172 size_t header_len;
173
174 if (listen_fd < 0 || !len)
175 return;
176
177 list_for_each_entry_safe(dc, tmp, &clients, node) {
178 if (!dc->header_sent && current_chunk) {
179 header_buf = vss_get_header(&header_len);
180 if (header_buf && header_len > 0) {
181 if (queue_chunk_or_shutdown(dc, -1U, 0) < 0)
182 continue;
183 }
184 dc->header_sent = 1;
185 }
186 ret = send_queued_chunks(dc);
187 if (ret < 0) {
188 dccp_shutdown_client(dc);
189 continue;
190 }
191 // PARA_DEBUG_LOG("writing %d bytes to fd %d\n", len, dc->fd);
192 ret = dccp_write(dc->fd, buf, len);
193 if (ret < 0) {
194 PARA_NOTICE_LOG("%s\n", PARA_STRERROR(-ret));
195 dccp_shutdown_client(dc);
196 continue;
197 }
198 if (ret != len)
199 queue_chunk_or_shutdown(dc, current_chunk, ret);
200 }
201 }
202
203 static void dccp_shutdown_clients(void)
204 {
205 struct dccp_client *dc, *tmp;
206
207 list_for_each_entry_safe(dc, tmp, &clients, node)
208 dccp_shutdown_client(dc);
209 }
210
211 static char *dccp_info(void)
212 {
213 static char *buf;
214 int num_clients = 0;
215 struct dccp_client *dc, *tmp;
216
217 free(buf);
218 list_for_each_entry_safe(dc, tmp, &clients, node)
219 num_clients++;
220 buf = make_message("dccp connected clients: %d\n", num_clients);
221 return buf;
222 }
223
224 static char *dccp_help(void)
225 {
226 return make_message("no help available\n");
227 }
228
229 /**
230 * the init function of the dccp sender
231 *
232 * \param s pointer to the dccp sender struct
233 *
234 * It initializes all function pointers of \a s and starts
235 * listening on the given port.
236 */
237 void dccp_send_init(struct sender *s)
238 {
239 int ret;
240
241 INIT_LIST_HEAD(&clients);
242 s->info = dccp_info;
243 s->send = dccp_send;
244 s->pre_select = dccp_pre_select;
245 s->post_select = dccp_post_select;
246 s->shutdown_clients = dccp_shutdown_clients;
247 s->help = dccp_help;
248 s->client_cmds[SENDER_ON] = NULL;
249 s->client_cmds[SENDER_OFF] = NULL;
250 s->client_cmds[SENDER_DENY] = NULL;
251 s->client_cmds[SENDER_ALLOW] = NULL;
252 s->client_cmds[SENDER_ADD] = NULL;
253 s->client_cmds[SENDER_DELETE] = NULL;
254 self = s;
255 ret = dccp_open();
256 if (ret < 0) {
257 PARA_ERROR_LOG("%s\n", PARA_STRERROR(-ret));
258 s->status = SENDER_OFF;
259 } else
260 s->status = SENDER_ON;
261 }