Ruby  2.1.10p492(2016-04-01revision54464)
udpsocket.c
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1 /************************************************
2 
3  udpsocket.c -
4 
5  created at: Thu Mar 31 12:21:29 JST 1994
6 
7  Copyright (C) 1993-2007 Yukihiro Matsumoto
8 
9 ************************************************/
10 
11 #include "rubysocket.h"
12 
13 /*
14  * call-seq:
15  * UDPSocket.new([address_family]) => socket
16  *
17  * Creates a new UDPSocket object.
18  *
19  * _address_family_ should be an integer, a string or a symbol:
20  * Socket::AF_INET, "AF_INET", :INET, etc.
21  *
22  * UDPSocket.new #=> #<UDPSocket:fd 3>
23  * UDPSocket.new(Socket::AF_INET6) #=> #<UDPSocket:fd 4>
24  *
25  */
26 static VALUE
28 {
29  VALUE arg;
30  int family = AF_INET;
31  int fd;
32 
33  rb_secure(3);
34  if (rb_scan_args(argc, argv, "01", &arg) == 1) {
35  family = rsock_family_arg(arg);
36  }
37  fd = rsock_socket(family, SOCK_DGRAM, 0);
38  if (fd < 0) {
39  rb_sys_fail("socket(2) - udp");
40  }
41 
42  return rsock_init_sock(sock, fd);
43 }
44 
45 struct udp_arg
46 {
47  struct rb_addrinfo *res;
48  int fd;
49 };
50 
51 static VALUE
53 {
54  int fd = arg->fd;
55  struct addrinfo *res;
56 
57  for (res = arg->res->ai; res; res = res->ai_next) {
58  if (rsock_connect(fd, res->ai_addr, res->ai_addrlen, 0) >= 0) {
59  return Qtrue;
60  }
61  }
62  return Qfalse;
63 }
64 
65 /*
66  * call-seq:
67  * udpsocket.connect(host, port) => 0
68  *
69  * Connects _udpsocket_ to _host_:_port_.
70  *
71  * This makes possible to send without destination address.
72  *
73  * u1 = UDPSocket.new
74  * u1.bind("127.0.0.1", 4913)
75  * u2 = UDPSocket.new
76  * u2.connect("127.0.0.1", 4913)
77  * u2.send "uuuu", 0
78  * p u1.recvfrom(10) #=> ["uuuu", ["AF_INET", 33230, "localhost", "127.0.0.1"]]
79  *
80  */
81 static VALUE
82 udp_connect(VALUE sock, VALUE host, VALUE port)
83 {
84  rb_io_t *fptr;
85  struct udp_arg arg;
86  VALUE ret;
87 
88  rb_secure(3);
89  arg.res = rsock_addrinfo(host, port, SOCK_DGRAM, 0);
90  GetOpenFile(sock, fptr);
91  arg.fd = fptr->fd;
93  rsock_freeaddrinfo, (VALUE)arg.res);
94  if (!ret) rsock_sys_fail_host_port("connect(2)", host, port);
95  return INT2FIX(0);
96 }
97 
98 /*
99  * call-seq:
100  * udpsocket.bind(host, port) #=> 0
101  *
102  * Binds _udpsocket_ to _host_:_port_.
103  *
104  * u1 = UDPSocket.new
105  * u1.bind("127.0.0.1", 4913)
106  * u1.send "message-to-self", 0, "127.0.0.1", 4913
107  * p u1.recvfrom(10) #=> ["message-to", ["AF_INET", 4913, "localhost", "127.0.0.1"]]
108  *
109  */
110 static VALUE
111 udp_bind(VALUE sock, VALUE host, VALUE port)
112 {
113  rb_io_t *fptr;
114  struct rb_addrinfo *res0;
115  struct addrinfo *res;
116 
117  rb_secure(3);
118  res0 = rsock_addrinfo(host, port, SOCK_DGRAM, 0);
119  GetOpenFile(sock, fptr);
120  for (res = res0->ai; res; res = res->ai_next) {
121  if (bind(fptr->fd, res->ai_addr, res->ai_addrlen) < 0) {
122  continue;
123  }
124  rb_freeaddrinfo(res0);
125  return INT2FIX(0);
126  }
127  rb_freeaddrinfo(res0);
128 
129  rsock_sys_fail_host_port("bind(2)", host, port);
130 
131  return INT2FIX(0);
132 }
133 
134 /*
135  * call-seq:
136  * udpsocket.send(mesg, flags, host, port) => numbytes_sent
137  * udpsocket.send(mesg, flags, sockaddr_to) => numbytes_sent
138  * udpsocket.send(mesg, flags) => numbytes_sent
139  *
140  * Sends _mesg_ via _udpsocket_.
141  *
142  * _flags_ should be a bitwise OR of Socket::MSG_* constants.
143  *
144  * u1 = UDPSocket.new
145  * u1.bind("127.0.0.1", 4913)
146  *
147  * u2 = UDPSocket.new
148  * u2.send "hi", 0, "127.0.0.1", 4913
149  *
150  * mesg, addr = u1.recvfrom(10)
151  * u1.send mesg, 0, addr[3], addr[1]
152  *
153  * p u2.recv(100) #=> "hi"
154  *
155  */
156 static VALUE
158 {
159  VALUE flags, host, port;
160  rb_io_t *fptr;
161  int n;
162  struct rb_addrinfo *res0;
163  struct addrinfo *res;
164  struct rsock_send_arg arg;
165 
166  if (argc == 2 || argc == 3) {
167  return rsock_bsock_send(argc, argv, sock);
168  }
169  rb_scan_args(argc, argv, "4", &arg.mesg, &flags, &host, &port);
170 
171  StringValue(arg.mesg);
172  res0 = rsock_addrinfo(host, port, SOCK_DGRAM, 0);
173  GetOpenFile(sock, fptr);
174  arg.fd = fptr->fd;
175  arg.flags = NUM2INT(flags);
176  for (res = res0->ai; res; res = res->ai_next) {
177  retry:
178  arg.to = res->ai_addr;
179  arg.tolen = res->ai_addrlen;
182  if (n >= 0) {
183  rb_freeaddrinfo(res0);
184  return INT2FIX(n);
185  }
186  if (rb_io_wait_writable(fptr->fd)) {
187  goto retry;
188  }
189  }
190  rb_freeaddrinfo(res0);
191  rsock_sys_fail_host_port("sendto(2)", host, port);
192  return INT2FIX(n);
193 }
194 
195 /*
196  * call-seq:
197  * udpsocket.recvfrom_nonblock(maxlen) => [mesg, sender_inet_addr]
198  * udpsocket.recvfrom_nonblock(maxlen, flags) => [mesg, sender_inet_addr]
199  *
200  * Receives up to _maxlen_ bytes from +udpsocket+ using recvfrom(2) after
201  * O_NONBLOCK is set for the underlying file descriptor.
202  * If _maxlen_ is omitted, its default value is 65536.
203  * _flags_ is zero or more of the +MSG_+ options.
204  * The first element of the results, _mesg_, is the data received.
205  * The second element, _sender_inet_addr_, is an array to represent the sender address.
206  *
207  * When recvfrom(2) returns 0,
208  * Socket#recvfrom_nonblock returns an empty string as data.
209  * It means an empty packet.
210  *
211  * === Parameters
212  * * +maxlen+ - the number of bytes to receive from the socket
213  * * +flags+ - zero or more of the +MSG_+ options
214  *
215  * === Example
216  * require 'socket'
217  * s1 = UDPSocket.new
218  * s1.bind("127.0.0.1", 0)
219  * s2 = UDPSocket.new
220  * s2.bind("127.0.0.1", 0)
221  * s2.connect(*s1.addr.values_at(3,1))
222  * s1.connect(*s2.addr.values_at(3,1))
223  * s1.send "aaa", 0
224  * begin # emulate blocking recvfrom
225  * p s2.recvfrom_nonblock(10) #=> ["aaa", ["AF_INET", 33302, "localhost.localdomain", "127.0.0.1"]]
226  * rescue IO::WaitReadable
227  * IO.select([s2])
228  * retry
229  * end
230  *
231  * Refer to Socket#recvfrom for the exceptions that may be thrown if the call
232  * to _recvfrom_nonblock_ fails.
233  *
234  * UDPSocket#recvfrom_nonblock may raise any error corresponding to recvfrom(2) failure,
235  * including Errno::EWOULDBLOCK.
236  *
237  * If the exception is Errno::EWOULDBLOCK or Errno::AGAIN,
238  * it is extended by IO::WaitReadable.
239  * So IO::WaitReadable can be used to rescue the exceptions for retrying recvfrom_nonblock.
240  *
241  * === See
242  * * Socket#recvfrom
243  */
244 static VALUE
246 {
247  return rsock_s_recvfrom_nonblock(sock, argc, argv, RECV_IP);
248 }
249 
250 void
252 {
253  /*
254  * Document-class: UDPSocket < IPSocket
255  *
256  * UDPSocket represents a UDP/IP socket.
257  *
258  */
260  rb_define_method(rb_cUDPSocket, "initialize", udp_init, -1);
264  rb_define_method(rb_cUDPSocket, "recvfrom_nonblock", udp_recvfrom_nonblock, -1);
265 }
266 
static VALUE udp_send(int argc, VALUE *argv, VALUE sock)
Definition: udpsocket.c:157
void rsock_init_udpsocket(void)
Definition: udpsocket.c:251
socklen_t tolen
Definition: rubysocket.h:322
VALUE rsock_sendto_blocking(void *data)
Definition: init.c:76
#define NUM2INT(x)
Definition: ruby.h:630
struct rb_addrinfo * res
Definition: udpsocket.c:47
#define Qtrue
Definition: ruby.h:426
Definition: io.h:61
VALUE rsock_init_sock(VALUE sock, int fd)
Definition: init.c:43
VALUE rb_cIPSocket
Definition: init.c:14
struct sockaddr * to
Definition: rubysocket.h:321
#define GetOpenFile(obj, fp)
Definition: io.h:118
static VALUE udp_bind(VALUE sock, VALUE host, VALUE port)
Definition: udpsocket.c:111
static VALUE udp_connect_internal(struct udp_arg *arg)
Definition: udpsocket.c:52
static VALUE udp_connect(VALUE sock, VALUE host, VALUE port)
Definition: udpsocket.c:82
VALUE rsock_bsock_send(int argc, VALUE *argv, VALUE sock)
Definition: basicsocket.c:542
void rb_freeaddrinfo(struct rb_addrinfo *ai)
Definition: raddrinfo.c:293
struct rb_addrinfo * rsock_addrinfo(VALUE host, VALUE port, int socktype, int flags)
Definition: raddrinfo.c:493
static VALUE udp_recvfrom_nonblock(int argc, VALUE *argv, VALUE sock)
Definition: udpsocket.c:245
int rb_thread_fd_writable(int)
Definition: thread.c:3529
static VALUE udp_init(int argc, VALUE *argv, VALUE sock)
Definition: udpsocket.c:27
int rsock_family_arg(VALUE domain)
Definition: constants.c:43
int rsock_socket(int domain, int type, int proto)
Definition: init.c:288
VALUE rb_define_class(const char *name, VALUE super)
Defines a top-level class.
Definition: class.c:611
int fd
Definition: io.h:62
int rb_io_wait_writable(int)
Definition: io.c:1103
int argc
Definition: ruby.c:131
#define Qfalse
Definition: ruby.h:425
VALUE rsock_freeaddrinfo(VALUE arg)
Definition: raddrinfo.c:642
int rb_scan_args(int argc, const VALUE *argv, const char *fmt,...)
Definition: class.c:1719
void rsock_sys_fail_host_port(const char *mesg, VALUE host, VALUE port)
Definition: socket.c:16
unsigned long VALUE
Definition: ruby.h:88
VALUE rb_ensure(VALUE(*b_proc)(ANYARGS), VALUE data1, VALUE(*e_proc)(ANYARGS), VALUE data2)
Definition: eval.c:839
void rb_sys_fail(const char *mesg)
Definition: error.c:1976
#define INT2FIX(i)
Definition: ruby.h:231
struct addrinfo * ai
Definition: rubysocket.h:282
int rsock_connect(int fd, const struct sockaddr *sockaddr, int len, int socks)
Definition: init.c:389
int fd
Definition: udpsocket.c:48
struct addrinfo * ai_next
Definition: addrinfo.h:139
void rb_secure(int)
Definition: safe.c:88
size_t ai_addrlen
Definition: addrinfo.h:136
VALUE rsock_s_recvfrom_nonblock(VALUE sock, int argc, VALUE *argv, enum sock_recv_type from)
Definition: init.c:182
void rb_define_method(VALUE klass, const char *name, VALUE(*func)(ANYARGS), int argc)
Definition: class.c:1479
struct sockaddr * ai_addr
Definition: addrinfo.h:138
#define BLOCKING_REGION_FD(func, arg)
Definition: rubysocket.h:259
char ** argv
Definition: ruby.c:132
#define StringValue(v)
Definition: ruby.h:539
VALUE rb_cUDPSocket
Definition: init.c:17