7b7c80517f7dee6d5fa7c2a34cf4993cd0dbe28b
[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 /** Do not write more than that many bytes at once. */
40 #define DCCP_MAX_BYTES_PER_WRITE 1024
41
42 static void dccp_pre_select(int *max_fileno, fd_set *rfds,
43 __a_unused fd_set *wfds)
44 {
45 if (listen_fd >= 0)
46 para_fd_set(listen_fd, rfds, max_fileno);
47 }
48
49 static void dccp_post_select(fd_set *rfds, __a_unused fd_set *wfds)
50 {
51 struct sender_client *sc;
52 int ret, fd;
53
54 if (listen_fd < 0 || !FD_ISSET(listen_fd, rfds))
55 return;
56 ret = para_accept(listen_fd, NULL, 0);
57 if (ret < 0) {
58 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
59 return;
60 }
61 fd = ret;
62 /*
63 * Bypass unused CCID paths: the sender does not receive application data
64 * from the client; by shutting down this unused communication path we can
65 * reduce processing costs a bit. See analogous comment in dccp_recv.c.
66 */
67 if (shutdown(fd, SHUT_RD) < 0) {
68 ret = -ERRNO_TO_PARA_ERROR(errno);
69 goto err;
70 }
71 ret = mark_fd_nonblocking(fd);
72 if (ret < 0)
73 goto err;
74 sc = para_calloc(sizeof(*sc));
75 sc->fd = fd;
76 sc->name = make_message("%s", remote_name(sc->fd));
77 PARA_NOTICE_LOG("connection from %s\n", sc->name);
78 para_list_add(&sc->node, &clients);
79 add_close_on_fork_list(sc->fd);
80 sc->cq = cq_new(DCCP_MAX_PENDING_BYTES);
81 return;
82 err:
83 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
84 close(fd);
85 }
86
87 static void dccp_send(long unsigned current_chunk,
88 __a_unused long unsigned chunks_sent, const char *buf, size_t len)
89 {
90 struct sender_client *sc, *tmp;
91
92 list_for_each_entry_safe(sc, tmp, &clients, node)
93 send_chunk(sc, DCCP_MAX_BYTES_PER_WRITE, current_chunk, buf,
94 len);
95 }
96
97 static void dccp_shutdown_clients(void)
98 {
99 struct sender_client *sc, *tmp;
100
101 list_for_each_entry_safe(sc, tmp, &clients, node)
102 shutdown_client(sc);
103 }
104
105 static char *dccp_info(void)
106 {
107 int num_clients = 0;
108 struct sender_client *sc, *tmp;
109
110 list_for_each_entry_safe(sc, tmp, &clients, node)
111 num_clients++;
112 return make_message("dccp connected clients: %d\n", num_clients);
113 }
114
115 static char *dccp_help(void)
116 {
117 return make_message("no help available\n");
118 }
119
120 /**
121 * The init function of the dccp sender.
122 *
123 * \param s pointer to the dccp sender struct.
124 *
125 * It initializes all function pointers of \a s and starts
126 * listening on the given port.
127 */
128 void dccp_send_init(struct sender *s)
129 {
130 int ret;
131
132 INIT_LIST_HEAD(&clients);
133 s->info = dccp_info;
134 s->send = dccp_send;
135 s->pre_select = dccp_pre_select;
136 s->post_select = dccp_post_select;
137 s->shutdown_clients = dccp_shutdown_clients;
138 s->help = dccp_help;
139 s->client_cmds[SENDER_ON] = NULL;
140 s->client_cmds[SENDER_OFF] = NULL;
141 s->client_cmds[SENDER_DENY] = NULL;
142 s->client_cmds[SENDER_ALLOW] = NULL;
143 s->client_cmds[SENDER_ADD] = NULL;
144 s->client_cmds[SENDER_DELETE] = NULL;
145 ret = open_sender(IPPROTO_DCCP, conf.dccp_port_arg);
146 if (ret < 0)
147 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
148 else
149 listen_fd = ret;
150 }