Class: UNIXSocket

Inherits:
BasicSocket show all
Defined in:
unixsocket.c,
unixsocket.c

Overview

UNIXSocket represents a UNIX domain stream client socket.

Direct Known Subclasses

UNIXServer

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from BasicSocket

#close_read, #close_write, #connect_address, do_not_reverse_lookup, #do_not_reverse_lookup, do_not_reverse_lookup=, #do_not_reverse_lookup=, for_fd, #getpeereid, #getpeername, #getsockname, #getsockopt, #local_address, #read_nonblock, #recv, #recv_nonblock, #recvmsg, #recvmsg_nonblock, #remote_address, #send, #sendmsg, #sendmsg_nonblock, #setsockopt, #shutdown, #write_nonblock

Constructor Details

#new(path) ⇒ Object

Creates a new UNIX client socket connected to path.

require 'socket'

s = UNIXSocket.new("/tmp/sock")
s.send "hello", 0



129
130
131
132
133
 
# File 'unixsocket.c', line 129

static VALUE
unix_init(VALUE self, VALUE path)
{
    return rsock_init_unixsock(self, path, 0);
}

Class Method Details

.pair([type [, protocol]]) ⇒ Array .socketpair([type [, protocol]]) ⇒ Array

Creates a pair of sockets connected to each other.

type should be a socket type such as: :STREAM, :DGRAM, :RAW, etc.

protocol should be a protocol defined in the domain. 0 is default protocol for the domain.

s1, s2 = UNIXSocket.pair
s1.send "a", 0
s1.send "b", 0
p s2.recv(10) #=> "ab"

Overloads:

  • .pair([type [, protocol]]) ⇒ Array

    Returns:

    • (Array)
  • .socketpair([type [, protocol]]) ⇒ Array

    Returns:

    • (Array) 


556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
 
# File 'unixsocket.c', line 556

static VALUE
unix_s_socketpair(int argc, VALUE *argv, VALUE klass)
{
    VALUE domain, type, protocol;
    VALUE args[3];

    domain = INT2FIX(PF_UNIX);
    rb_scan_args(argc, argv, "02", &type, &protocol);
    if (argc == 0)
        type = INT2FIX(SOCK_STREAM);
    if (argc <= 1)
        protocol = INT2FIX(0);

    args[0] = domain;
    args[1] = type;
    args[2] = protocol;

    return rsock_sock_s_socketpair(3, args, klass);
}

.pair([type [, protocol]]) ⇒ Array .socketpair([type [, protocol]]) ⇒ Array

Creates a pair of sockets connected to each other.

type should be a socket type such as: :STREAM, :DGRAM, :RAW, etc.

protocol should be a protocol defined in the domain. 0 is default protocol for the domain.

s1, s2 = UNIXSocket.pair
s1.send "a", 0
s1.send "b", 0
p s2.recv(10) #=> "ab"

Overloads:

  • .pair([type [, protocol]]) ⇒ Array

    Returns:

    • (Array)
  • .socketpair([type [, protocol]]) ⇒ Array

    Returns:

    • (Array) 


556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
 
# File 'unixsocket.c', line 556

static VALUE
unix_s_socketpair(int argc, VALUE *argv, VALUE klass)
{
    VALUE domain, type, protocol;
    VALUE args[3];

    domain = INT2FIX(PF_UNIX);
    rb_scan_args(argc, argv, "02", &type, &protocol);
    if (argc == 0)
        type = INT2FIX(SOCK_STREAM);
    if (argc <= 1)
        protocol = INT2FIX(0);

    args[0] = domain;
    args[1] = type;
    args[2] = protocol;

    return rsock_sock_s_socketpair(3, args, klass);
}

Instance Method Details

#addr ⇒ Array

Returns the local address as an array which contains address_family and unix_path.

Example

serv = UNIXServer.new("/tmp/sock")
p serv.addr #=> ["AF_UNIX", "/tmp/sock"]

Returns:

  • (Array) 


494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
 
# File 'unixsocket.c', line 494

static VALUE
unix_addr(VALUE sock)
{
    rb_io_t *fptr;
    struct sockaddr_un addr;
    socklen_t len = (socklen_t)sizeof addr;
    socklen_t len0 = len;

    GetOpenFile(sock, fptr);

    if (getsockname(fptr->fd, (struct sockaddr*)&addr, &len) < 0)
        rsock_sys_fail_path("getsockname(2)", fptr->pathv);
    if (len0 < len) len = len0;
    return rsock_unixaddr(&addr, len);
}

#path ⇒ Object

Returns the path of the local address of unixsocket.

s = UNIXServer.new("/tmp/sock")
p s.path #=> "/tmp/sock"



145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
 
# File 'unixsocket.c', line 145

static VALUE
unix_path(VALUE sock)
{
    rb_io_t *fptr;

    GetOpenFile(sock, fptr);
    if (NIL_P(fptr->pathv)) {
        struct sockaddr_un addr;
        socklen_t len = (socklen_t)sizeof(addr);
        socklen_t len0 = len;
        if (getsockname(fptr->fd, (struct sockaddr*)&addr, &len) < 0)
            rsock_sys_fail_path("getsockname(2)", fptr->pathv);
        if (len0 < len) len = len0;
        fptr->pathv = rb_obj_freeze(rsock_unixpath_str(&addr, len));
    }
    return rb_str_dup(fptr->pathv);
}

#peeraddr ⇒ Array

Returns the remote address as an array which contains address_family and unix_path.

Example

serv = UNIXServer.new("/tmp/sock")
c = UNIXSocket.new("/tmp/sock")
p c.peeraddr #=> ["AF_UNIX", "/tmp/sock"]

Returns:

  • (Array) 


522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
 
# File 'unixsocket.c', line 522

static VALUE
unix_peeraddr(VALUE sock)
{
    rb_io_t *fptr;
    struct sockaddr_un addr;
    socklen_t len = (socklen_t)sizeof addr;
    socklen_t len0 = len;

    GetOpenFile(sock, fptr);

    if (getpeername(fptr->fd, (struct sockaddr*)&addr, &len) < 0)
        rsock_sys_fail_path("getpeername(2)", fptr->pathv);
    if (len0 < len) len = len0;
    return rsock_unixaddr(&addr, len);
}

#recv_io([klass [, mode]]) ⇒ IO

Example

UNIXServer.open("/tmp/sock") {|serv|
  UNIXSocket.open("/tmp/sock") {|c|
    s = serv.accept

    c.send_io STDOUT
    stdout = s.recv_io

    p STDOUT.fileno #=> 1
    p stdout.fileno #=> 7

    stdout.puts "hello" # outputs "hello\n" to standard output.
  }
}

klass will determine the class of io returned (using the IO.for_fd singleton method or similar). If klass is nil, an integer file descriptor is returned.

mode is the same as the argument passed to IO.for_fd

Returns:

  • (IO) 


339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
 
# File 'unixsocket.c', line 339

static VALUE
unix_recv_io(int argc, VALUE *argv, VALUE sock)
{
    VALUE klass, mode;
    rb_io_t *fptr;
    struct iomsg_arg arg;
    struct iovec vec[2];
    char buf[1];
    unsigned int gc_reason = 0;
    enum {
        GC_REASON_EMSGSIZE = 0x1,
        GC_REASON_TRUNCATE = 0x2,
        GC_REASON_ENOMEM = 0x4
    };

    int fd;
#if FD_PASSING_BY_MSG_CONTROL
    union {
        struct cmsghdr hdr;
        char pad[sizeof(struct cmsghdr)+8+sizeof(int)+8];
    } cmsg;
#endif

    rb_scan_args(argc, argv, "02", &klass, &mode);
    if (argc == 0)
        klass = rb_cIO;
    if (argc <= 1)
        mode = Qnil;

retry:
    GetOpenFile(sock, fptr);

    arg.msg.msg_name = NULL;
    arg.msg.msg_namelen = 0;

    vec[0].iov_base = buf;
    vec[0].iov_len = sizeof(buf);
    arg.msg.msg_iov = vec;
    arg.msg.msg_iovlen = 1;

#if FD_PASSING_BY_MSG_CONTROL
    arg.msg.msg_control = (caddr_t)&cmsg;
    arg.msg.msg_controllen = (socklen_t)CMSG_SPACE(sizeof(int));
    arg.msg.msg_flags = 0;
    cmsg.hdr.cmsg_len = (socklen_t)CMSG_LEN(sizeof(int));
    cmsg.hdr.cmsg_level = SOL_SOCKET;
    cmsg.hdr.cmsg_type = SCM_RIGHTS;
    fd = -1;
    memcpy(CMSG_DATA(&cmsg.hdr), &fd, sizeof(int));
#else
    arg.msg.msg_accrights = (caddr_t)&fd;
    arg.msg.msg_accrightslen = sizeof(fd);
    fd = -1;
#endif

    arg.fd = fptr->fd;
    while ((int)rb_io_blocking_region(fptr, recvmsg_blocking, &arg) == -1) {
        int e = errno;
        if (e == EMSGSIZE && !(gc_reason & GC_REASON_EMSGSIZE)) {
            /* FreeBSD gets here when we're out of FDs */
            gc_reason |= GC_REASON_EMSGSIZE;
            rb_gc_for_fd(EMFILE);
            goto retry;
        }
        else if (e == ENOMEM && !(gc_reason & GC_REASON_ENOMEM)) {
            /* ENOMEM is documented in recvmsg manpages */
            gc_reason |= GC_REASON_ENOMEM;
            rb_gc_for_fd(e);
            goto retry;
        }
        if (!rb_io_wait_readable(arg.fd))
            rsock_syserr_fail_path(e, "recvmsg(2)", fptr->pathv);
    }

#if FD_PASSING_BY_MSG_CONTROL
    if (arg.msg.msg_controllen < (socklen_t)sizeof(struct cmsghdr)) {
        /* FreeBSD and Linux both get here when we're out of FDs */
        if (!(gc_reason & GC_REASON_TRUNCATE)) {
            gc_reason |= GC_REASON_TRUNCATE;
            rb_gc_for_fd(EMFILE);
            goto retry;
        }
        rb_raise(rb_eSocket,
                 "file descriptor was not passed (msg_controllen=%d smaller than sizeof(struct cmsghdr)=%d)",
                 (int)arg.msg.msg_controllen, (int)sizeof(struct cmsghdr));
    }
    if (cmsg.hdr.cmsg_level != SOL_SOCKET) {
        rb_raise(rb_eSocket,
                 "file descriptor was not passed (cmsg_level=%d, %d expected)",
                 cmsg.hdr.cmsg_level, SOL_SOCKET);
    }
    if (cmsg.hdr.cmsg_type != SCM_RIGHTS) {
        rb_raise(rb_eSocket,
                 "file descriptor was not passed (cmsg_type=%d, %d expected)",
                 cmsg.hdr.cmsg_type, SCM_RIGHTS);
    }
    if (arg.msg.msg_controllen < (socklen_t)CMSG_LEN(sizeof(int))) {
        rb_raise(rb_eSocket,
                 "file descriptor was not passed (msg_controllen=%d smaller than CMSG_LEN(sizeof(int))=%d)",
                 (int)arg.msg.msg_controllen, (int)CMSG_LEN(sizeof(int)));
    }
    if ((socklen_t)CMSG_SPACE(sizeof(int)) < arg.msg.msg_controllen) {
        rb_raise(rb_eSocket,
                 "file descriptor was not passed (msg_controllen=%d bigger than CMSG_SPACE(sizeof(int))=%d)",
                 (int)arg.msg.msg_controllen, (int)CMSG_SPACE(sizeof(int)));
    }
    if (cmsg.hdr.cmsg_len != CMSG_LEN(sizeof(int))) {
        rsock_discard_cmsg_resource(&arg.msg, 0);
        rb_raise(rb_eSocket,
                 "file descriptor was not passed (cmsg_len=%d, %d expected)",
                 (int)cmsg.hdr.cmsg_len, (int)CMSG_LEN(sizeof(int)));
    }
#else
    if (arg.msg.msg_accrightslen != sizeof(fd)) {
        rb_raise(rb_eSocket,
                 "file descriptor was not passed (accrightslen=%d, %d expected)",
                 arg.msg.msg_accrightslen, (int)sizeof(fd));
    }
#endif

#if FD_PASSING_BY_MSG_CONTROL
    memcpy(&fd, CMSG_DATA(&cmsg.hdr), sizeof(int));
#endif

    rb_update_max_fd(fd);
    rb_maygvl_fd_fix_cloexec(fd);

    if (klass == Qnil)
        return INT2FIX(fd);
    else {
        ID for_fd;
        int ff_argc;
        VALUE ff_argv[2];
        CONST_ID(for_fd, "for_fd");
        ff_argc = mode == Qnil ? 1 : 2;
        ff_argv[0] = INT2FIX(fd);
        ff_argv[1] = mode;
        return rb_funcallv(klass, for_fd, ff_argc, ff_argv);
    }
}

#recvfrom(maxlen[, flags[, outbuf]]) ⇒ Array

Receives a message via unixsocket.

maxlen is the maximum number of bytes to receive.

flags should be a bitwise OR of Socket::MSG_* constants.

outbuf will contain only the received data after the method call even if it is not empty at the beginning.

s1 = Socket.new(:UNIX, :DGRAM, 0)
s1_ai = Addrinfo.unix("/tmp/sock1")
s1.bind(s1_ai)

s2 = Socket.new(:UNIX, :DGRAM, 0)
s2_ai = Addrinfo.unix("/tmp/sock2")
s2.bind(s2_ai)
s3 = UNIXSocket.for_fd(s2.fileno)

s1.send "a", 0, s2_ai
p s3.recvfrom(10) #=> ["a", ["AF_UNIX", "/tmp/sock1"]]

Returns:

  • (Array) 


189
190
191
192
193
 
# File 'unixsocket.c', line 189

static VALUE
unix_recvfrom(int argc, VALUE *argv, VALUE sock)
{
    return rsock_s_recvfrom(sock, argc, argv, RECV_UNIX);
}

#send_io(io) ⇒ nil

Sends io as file descriptor passing.

s1, s2 = UNIXSocket.pair

s1.send_io STDOUT
stdout = s2.recv_io

p STDOUT.fileno #=> 1
p stdout.fileno #=> 6

stdout.puts "hello" # outputs "hello\n" to standard output.

io may be any kind of IO object or integer file descriptor.

Returns:

  • (nil) 


238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
 
# File 'unixsocket.c', line 238

static VALUE
unix_send_io(VALUE sock, VALUE val)
{
    int fd;
    rb_io_t *fptr;
    struct iomsg_arg arg;
    struct iovec vec[1];
    char buf[1];

#if FD_PASSING_BY_MSG_CONTROL
    union {
        struct cmsghdr hdr;
        char pad[sizeof(struct cmsghdr)+8+sizeof(int)+8];
    } cmsg;
#endif

    if (rb_obj_is_kind_of(val, rb_cIO)) {
        rb_io_t *valfptr;
        GetOpenFile(val, valfptr);
        fd = valfptr->fd;
    }
    else if (FIXNUM_P(val)) {
        fd = FIX2INT(val);
    }
    else {
        rb_raise(rb_eTypeError, "neither IO nor file descriptor");
    }

    GetOpenFile(sock, fptr);

    arg.msg.msg_name = NULL;
    arg.msg.msg_namelen = 0;

    /* Linux and Solaris doesn't work if msg_iov is NULL. */
    buf[0] = '\0';
    vec[0].iov_base = buf;
    vec[0].iov_len = 1;
    arg.msg.msg_iov = vec;
    arg.msg.msg_iovlen = 1;

#if FD_PASSING_BY_MSG_CONTROL
    arg.msg.msg_control = (caddr_t)&cmsg;
    arg.msg.msg_controllen = (socklen_t)CMSG_LEN(sizeof(int));
    arg.msg.msg_flags = 0;
    MEMZERO((char*)&cmsg, char, sizeof(cmsg));
    cmsg.hdr.cmsg_len = (socklen_t)CMSG_LEN(sizeof(int));
    cmsg.hdr.cmsg_level = SOL_SOCKET;
    cmsg.hdr.cmsg_type = SCM_RIGHTS;
    memcpy(CMSG_DATA(&cmsg.hdr), &fd, sizeof(int));
#else
    arg.msg.msg_accrights = (caddr_t)&fd;
    arg.msg.msg_accrightslen = sizeof(fd);
#endif

    arg.fd = fptr->fd;
    while ((int)rb_io_blocking_region(fptr, sendmsg_blocking, &arg) == -1) {
        if (!rb_io_wait_writable(arg.fd))
            rsock_sys_fail_path("sendmsg(2)", fptr->pathv);
    }

    return Qnil;
}