23cc34f811efedc58b7fdcb73e28c8485bf8714c
13 #include <sys/utsname.h>
15 static VALUE sym_EAGAIN
;
16 #define WAITALL 0x4000000
18 #ifndef F_LINUX_SPECIFIC_BASE
19 # define F_LINUX_SPECIFIC_BASE 1024
23 # define F_SETPIPE_SZ (F_LINUX_SPECIFIC_BASE + 7)
24 # define F_GETPIPE_SZ (F_LINUX_SPECIFIC_BASE + 8)
28 # define rb_io_t OpenFile
32 # define FPTR_TO_FD(fptr) (fileno(GetReadFile(fptr)))
34 # if !HAVE_RB_IO_T || (RUBY_VERSION_MAJOR == 1 && RUBY_VERSION_MINOR == 8)
35 # define FPTR_TO_FD(fptr) fileno(fptr->f)
37 # define FPTR_TO_FD(fptr) fptr->fd
42 # define SSIZET2NUM(x) LONG2NUM(x)
45 # define NUM2SSIZET(x) NUM2LONG(x)
48 # define SIZET2NUM(x) ULONG2NUM(x)
51 # define NUM2SIZET(x) NUM2ULONG(x)
54 static int my_fileno(VALUE io
)
60 case T_FIXNUM
: return FIX2INT(io
);
62 GetOpenFile(io
, fptr
);
63 return FPTR_TO_FD(fptr
);
66 io
= rb_convert_type(io
, T_FILE
, "IO", "to_io");
72 static int check_fileno(VALUE io
)
74 int saved_errno
= errno
;
75 int fd
= my_fileno(io
);
79 #ifndef HAVE_RB_THREAD_BLOCKING_REGION
80 /* partial emulation of the 1.9 rb_thread_blocking_region under 1.8 */
82 # define RUBY_UBF_IO ((rb_unblock_function_t *)-1)
83 typedef void rb_unblock_function_t(void *);
84 typedef VALUE
rb_blocking_function_t(void *);
86 rb_thread_blocking_region(
87 rb_blocking_function_t
*fn
, void *data1
,
88 rb_unblock_function_t
*ubf
, void *data2
)
92 assert(RUBY_UBF_IO
== ubf
&& "RUBY_UBF_IO required for emulation");
100 #endif /* ! HAVE_RB_THREAD_BLOCKING_REGION */
103 # define RSTRING_PTR(s) (RSTRING(s)->ptr)
106 # define RSTRING_LEN(s) (RSTRING(s)->len)
109 # define RARRAY_PTR(s) (RARRAY(s)->ptr)
112 # define RARRAY_LEN(s) (RARRAY(s)->len)
115 static VALUE
io_run(rb_blocking_function_t
*fn
, void *data
)
117 return rb_thread_blocking_region(fn
, data
, RUBY_UBF_IO
, 0);
129 static VALUE
nogvl_splice(void *ptr
)
131 struct splice_args
*a
= ptr
;
133 return (VALUE
)splice(a
->fd_in
, a
->off_in
, a
->fd_out
, a
->off_out
,
137 static ssize_t
do_splice(int argc
, VALUE
*argv
, unsigned dflags
)
140 VALUE io_in
, off_in
, io_out
, off_out
, len
, flags
;
141 struct splice_args a
;
146 rb_scan_args(argc
, argv
, "51",
147 &io_in
, &off_in
, &io_out
, &off_out
, &len
, &flags
);
149 a
.off_in
= NIL_P(off_in
) ? NULL
: (i
= NUM2OFFT(off_in
), &i
);
150 a
.off_out
= NIL_P(off_out
) ? NULL
: (o
= NUM2OFFT(off_out
), &o
);
151 a
.len
= NUM2SIZET(len
);
152 a
.flags
= NIL_P(flags
) ? dflags
: NUM2UINT(flags
) | dflags
;
153 waitall
= a
.flags
& WAITALL
;
158 a
.fd_in
= check_fileno(io_in
);
159 a
.fd_out
= check_fileno(io_out
);
160 bytes
= (ssize_t
)io_run(nogvl_splice
, &a
);
164 if (waitall
&& errno
== EAGAIN
) {
165 rb_io_wait_readable(check_fileno(io_in
));
167 rb_io_wait_writable(check_fileno(io_out
));
173 } else if (bytes
== 0) {
175 } else if (waitall
) {
177 if ((a
.len
-= bytes
) == 0)
191 * IO.splice(io_in, off_in, io_out, off_out, len) => integer
192 * IO.splice(io_in, off_in, io_out, off_out, len, flags) => integer
194 * Splice +len+ bytes from/to a pipe. Either +io_in+ or +io_out+
195 * MUST be a pipe. +io_in+ and +io_out+ may BOTH be pipes as of
196 * Linux 2.6.31 or later.
198 * +off_in+ and +off_out+ if non-nil may be used to
199 * specify an offset for the non-pipe file descriptor.
201 * +flags+ defaults to zero if unspecified.
202 * +flags+ may be a bitmask of the following flags:
204 * * IO::Splice::F_MOVE
205 * * IO::Splice::F_NONBLOCK
206 * * IO::Splice::F_MORE
207 * * IO::Splice::WAITALL
209 * Returns the number of bytes spliced.
210 * Raises EOFError when +io_in+ has reached end of file.
211 * Raises Errno::EAGAIN if the IO::Splice::F_NONBLOCK flag is set
212 * and the pipe has no data to read from or space to write to. May
213 * also raise Errno::EAGAIN if the non-pipe descriptor has no data
214 * to read from or space to write to.
216 * As splice never exposes buffers to userspace, it will not take
217 * into account userspace buffering done by Ruby or stdio. It is
218 * also not subject to encoding/decoding filters under Ruby 1.9.
220 * Consider using IO.trysplice if +io_out+ is a pipe or if you are using
221 * non-blocking I/O on both descriptors as it avoids the cost of raising
222 * common Errno::EAGAIN exceptions.
224 * See manpage for full documentation:
225 * http://kernel.org/doc/man-pages/online/pages/man2/splice.2.html
227 static VALUE
my_splice(int argc
, VALUE
*argv
, VALUE self
)
229 ssize_t n
= do_splice(argc
, argv
, 0);
234 rb_sys_fail("splice");
235 return SSIZET2NUM(n
);
240 * IO.trysplice(io_in, off_in, io_out, off_out, len) => integer
241 * IO.trysplice(io_in, off_in, io_out, off_out, len, flags) => integer
243 * Exactly like IO.splice, except +:EAGAIN+ is returned when either
244 * the read or write end would block instead of raising Errno::EAGAIN.
246 * IO::Splice::F_NONBLOCK is always passed for the pipe descriptor,
247 * but this can still block if the non-pipe descriptor is blocking.
249 * See IO.splice documentation for more details.
251 * This method is recommended whenever +io_out+ is a pipe.
253 static VALUE
trysplice(int argc
, VALUE
*argv
, VALUE self
)
255 ssize_t n
= do_splice(argc
, argv
, SPLICE_F_NONBLOCK
);
262 rb_sys_fail("splice");
264 return SSIZET2NUM(n
);
274 /* runs without GVL */
275 static VALUE
nogvl_tee(void *ptr
)
277 struct tee_args
*a
= ptr
;
279 return (VALUE
)tee(a
->fd_in
, a
->fd_out
, a
->len
, a
->flags
);
282 static ssize_t
do_tee(int argc
, VALUE
*argv
, unsigned dflags
)
284 VALUE io_in
, io_out
, len
, flags
;
290 rb_scan_args(argc
, argv
, "31", &io_in
, &io_out
, &len
, &flags
);
291 a
.len
= (size_t)NUM2SIZET(len
);
292 a
.flags
= NIL_P(flags
) ? dflags
: NUM2UINT(flags
) | dflags
;
293 waitall
= a
.flags
& WAITALL
;
298 a
.fd_in
= check_fileno(io_in
);
299 a
.fd_out
= check_fileno(io_out
);
300 bytes
= (ssize_t
)io_run(nogvl_tee
, &a
);
304 if (waitall
&& errno
== EAGAIN
) {
305 rb_io_wait_readable(check_fileno(io_in
));
307 rb_io_wait_writable(check_fileno(io_out
));
313 } else if (bytes
== 0) {
315 } else if (waitall
) {
317 if ((a
.len
-= bytes
) == 0)
329 * IO.tee(io_in, io_out, len) => integer
330 * IO.tee(io_in, io_out, len, flags) => integer
332 * Copies up to +len+ bytes of data from +io_in+ to +io_out+. +io_in+
333 * and +io_out+ must both refer to pipe descriptors. +io_in+ and +io_out+
334 * may not be endpoints of the same pipe.
336 * +flags+ may be zero (the default) or a combination of:
337 * * IO::Splice::F_NONBLOCK
338 * * IO::Splice::WAITALL
340 * Other IO::Splice flags are currently unimplemented or have no effect.
342 * Returns the number of bytes duplicated if successful.
343 * Raises EOFError when +io_in+ is closed and emptied.
344 * Raises Errno::EAGAIN when +io_in+ is empty and/or +io_out+ is full
345 * and +flags+ contains IO::Splice::F_NONBLOCK
347 * Consider using IO.trytee if you are using IO::Splice::F_NONBLOCK
348 * as it avoids the cost of raising common Errno::EAGAIN exceptions.
350 * See manpage for full documentation:
351 * http://kernel.org/doc/man-pages/online/pages/man2/tee.2.html
353 static VALUE
my_tee(int argc
, VALUE
*argv
, VALUE self
)
355 ssize_t n
= do_tee(argc
, argv
, 0);
362 return SSIZET2NUM(n
);
367 * IO.trytee(io_in, io_out, len) => integer
368 * IO.trytee(io_in, io_out, len, flags) => integer
370 * Exactly like IO.tee, except +:EAGAIN+ is returned when either
371 * the read or write end would block instead of raising Errno::EAGAIN.
373 * IO::Splice::F_NONBLOCK is always passed for the pipe descriptor,
374 * but this can still block if the non-pipe descriptor is blocking.
376 * See IO.tee documentation for more details.
378 static VALUE
trytee(int argc
, VALUE
*argv
, VALUE self
)
380 ssize_t n
= do_tee(argc
, argv
, SPLICE_F_NONBLOCK
);
390 return SSIZET2NUM(n
);
393 struct vmsplice_args
{
396 unsigned long nr_segs
;
400 static VALUE
nogvl_vmsplice(void *ptr
)
402 struct vmsplice_args
*a
= ptr
;
404 return (VALUE
)vmsplice(a
->fd
, a
->iov
, a
->nr_segs
, a
->flags
);
407 /* this can't be a function since we use alloca() */
408 #define ARY2IOVEC(iov,iovcnt,expect,ary) \
413 cur = RARRAY_PTR(ary); \
414 n = RARRAY_LEN(ary); \
416 rb_raise(rb_eArgError, "array is larger than IOV_MAX"); \
417 iov = tmp = alloca(sizeof(struct iovec) * n); \
420 for (; --n >= 0; tmp++, cur++) { \
421 Check_Type(*cur, T_STRING); \
422 tmp->iov_base = RSTRING_PTR(*cur); \
423 tmp->iov_len = RSTRING_LEN(*cur); \
424 expect += tmp->iov_len; \
428 static void advance_vmsplice_args(struct vmsplice_args
*a
, long n
)
430 struct iovec
*new_iov
= a
->iov
;
433 /* skip over iovecs we've already written completely */
434 for (i
= 0; i
< a
->nr_segs
; i
++, new_iov
++) {
438 * partially written iov,
439 * modify and retry with current iovec in
442 if (new_iov
->iov_len
> (size_t)n
) {
443 VALUE base
= (VALUE
)new_iov
->iov_base
;
445 new_iov
->iov_len
-= n
;
446 new_iov
->iov_base
= (void *)(base
+ n
);
450 n
-= new_iov
->iov_len
;
453 /* setup to retry without the already-written iovecs */
460 * IO.vmsplice(io, string_array) => integer
461 * IO.vmsplice(io, string_array, flags) => integer
462 * IO.vmsplice(io, string) => integer
463 * IO.vmsplice(io, string, flags) => integer
465 * Transfers an array of strings into the pipe descriptor given by io.
466 * +io+ must be the writable end of a pipe.
468 * This may allow the kernel to avoid data copies in some cases.
469 * but is (probably) of limited usefulness in Ruby. If you have
470 * use cases or ideas for making this more useful for Ruby users,
471 * please tell us at ruby.io.splice@librelist.com!
473 * Also consider the "sendfile" RubyGem or IO.copy_stream in Ruby 1.9
474 * if you want to do zero-copy file transfers to pipes or sockets. As
475 * of Linux 2.6.33, sendfile(2) can copy to any output descriptor,
478 * See manpage for full documentation:
479 * http://kernel.org/doc/man-pages/online/pages/man2/vmsplice.2.html
481 static VALUE
my_vmsplice(int argc
, VALUE
* argv
, VALUE self
)
485 struct vmsplice_args a
;
486 VALUE io
, data
, flags
;
488 rb_scan_args(argc
, argv
, "21", &io
, &data
, &flags
);
490 switch (TYPE(data
)) {
494 iov
.iov_base
= RSTRING_PTR(data
);
495 iov
.iov_len
= (size_t)(left
= (ssize_t
)RSTRING_LEN(data
));
501 ARY2IOVEC(a
.iov
, a
.nr_segs
, left
, data
);
504 rb_raise(rb_eTypeError
, "wrong argument type %s "
505 "(expected a String or Array of strings)",
506 rb_obj_classname(data
));
508 a
.fd
= my_fileno(io
);
509 a
.flags
= NIL_P(flags
) ? 0 : NUM2UINT(flags
);
512 ssize_t n
= (ssize_t
)io_run(nogvl_vmsplice
, &a
);
515 if (errno
== EAGAIN
) {
516 if (a
.flags
& SPLICE_F_NONBLOCK
) {
517 rb_sys_fail("vmsplice");
519 a
.fd
= check_fileno(io
);
520 if (rb_io_wait_writable(a
.fd
))
523 /* fall through on error */
526 * unlikely to hit this case, return the
527 * already written bytes, we'll let the next
528 * write (or close) fail instead
532 if (errno
== EINTR
) {
533 a
.fd
= check_fileno(io
);
536 rb_sys_fail("vmsplice");
543 advance_vmsplice_args(&a
, n
);
546 return SSIZET2NUM(rv
);
551 * reader, writer = IO.pipe
552 * reader.pipe_size => integer
554 * Returns the pipe capacity of the underlying pipe in bytes. The
555 * default capacity is 65536 bytes since Linux 2.6.11, and 4096 bytes
556 * in previous kernels.
558 * Since the pipe is a circular buffer in the same kernel, the size
559 * of the reader is exactly the same as the size of the writer.
561 * This method is only exposed on Linux 2.6.35 or later.
563 static VALUE
pipe_size(VALUE self
)
565 int size
= fcntl(my_fileno(self
), F_GETPIPE_SZ
);
568 rb_sys_fail("fcntl(F_GETPIPE_SZ)");
570 return INT2NUM(size
);
575 * reader, writer = IO.pipe
576 * reader.pipe_size = integer
578 * Sets and returns the pipe capacity of the underlying pipe in bytes.
580 * This MUST be a power-of-two, or Errno::EINVAL will be raised.
581 * Linux will silently increase this to be equal to the page size
582 * (4096 bytes on most architectures) if the specified value is
583 * less than the size of a page.
585 * For users without CAP_SYS_RESOURCE, this raises Errno::EPERM when
586 * attempting to specify a value greater than the value in
587 * /proc/sys/fs/pipe-max-size.
589 * Since the pipe is a circular buffer in the same kernel, the size
590 * of the reader is exactly the same as the size of the writer.
592 * Raises Errno::EBUSY if the assigned value is less than
593 * the currently filled portion of the pipe.
595 * This method is only exposed on Linux 2.6.35 or later.
597 static VALUE
set_pipe_size(VALUE self
, VALUE size
)
599 int fd
= my_fileno(self
);
600 int bytes
= NUM2INT(size
);
601 int rv
= fcntl(fd
, F_SETPIPE_SZ
, bytes
);
604 if (errno
== ENOMEM
) {
606 rv
= fcntl(fd
, F_SETPIPE_SZ
, bytes
);
609 rb_sys_fail("fcntl(F_SETPIPE_SZ)");
615 void Init_io_splice_ext(void)
617 VALUE mSplice
= rb_define_module_under(rb_cIO
, "Splice");
618 struct utsname utsname
;
620 rb_define_singleton_method(rb_cIO
, "splice", my_splice
, -1);
621 rb_define_singleton_method(rb_cIO
, "trysplice", trysplice
, -1);
622 rb_define_singleton_method(rb_cIO
, "tee", my_tee
, -1);
623 rb_define_singleton_method(rb_cIO
, "trytee", trytee
, -1);
624 rb_define_singleton_method(rb_cIO
, "vmsplice", my_vmsplice
, -1);
627 * Attempt to move pages instead of copying. This is only a hint
628 * and support for it was removed in Linux 2.6.21. It will be
629 * re-added for FUSE filesystems only in Linux 2.6.35.
631 rb_define_const(mSplice
, "F_MOVE", UINT2NUM(SPLICE_F_MOVE
));
632 assert(WAITALL
!= SPLICE_F_MOVE
&& "WAITALL == F_MOVE");
635 * Do not block on pipe I/O. This flag only affects the pipe(s)
636 * being spliced from/to and has no effect on the non-pipe
637 * descriptor (which requires non-blocking operation to be set
640 * The non-blocking flag (O_NONBLOCK) on the pipe descriptors
641 * themselves are ignored by this family of functions, and
642 * using this flag is the only way to get non-blocking operation
645 * It is highly recommended this flag be set (or IO.trysplice used)
646 * whenever splicing from a socket into a pipe unless there is
647 * another (native) thread or process doing a blocking read on that
648 * pipe. Otherwise it is possible to block a single-threaded process
649 * if the socket buffers are larger than the pipe buffers.
651 rb_define_const(mSplice
, "F_NONBLOCK", UINT2NUM(SPLICE_F_NONBLOCK
));
652 assert(WAITALL
!= SPLICE_F_NONBLOCK
&& "WAITALL == F_NONBLOCK");
655 * Indicate that there may be more data coming into the outbound
656 * descriptor. This can allow the kernel to avoid sending partial
657 * frames from sockets. Currently only used with splice.
659 rb_define_const(mSplice
, "F_MORE", UINT2NUM(SPLICE_F_MORE
));
660 assert(WAITALL
!= SPLICE_F_MORE
&& "WAITALL == F_MORE");
663 * Only usable by vmsplice. This flag probably not useful in the
664 * context of Ruby applications which cannot control alignment.
666 rb_define_const(mSplice
, "F_GIFT", UINT2NUM(SPLICE_F_GIFT
));
667 assert(WAITALL
!= SPLICE_F_GIFT
&& "WAITALL == F_GIFT");
670 * Retry until the requested transfer is complete, this will
671 * cause IO.splice/IO.tee to never return less than the requested
672 * transfer size unless an error occored.
674 * IO.vmsplice always defaults to this behavior.
676 rb_define_const(mSplice
, "WAITALL", UINT2NUM(WAITALL
));
679 * The maximum size of an atomic write to a pipe
680 * POSIX requires this to be at least 512 bytes.
681 * Under Linux, this is 4096 bytes.
683 rb_define_const(mSplice
, "PIPE_BUF", UINT2NUM(PIPE_BUF
));
685 if (uname(&utsname
) == -1)
686 rb_sys_fail("uname");
688 /* includes 2.6.35-rc[1-6] */
689 if (strcmp(utsname
.release
, "2.6.35") >= 0) {
690 rb_define_method(rb_cIO
, "pipe_size", pipe_size
, 0);
691 rb_define_method(rb_cIO
, "pipe_size=", set_pipe_size
, 1);
694 * fcntl() command constant used to return the size of a pipe.
695 * This constant is only defined when running Linux 2.6.35
696 * or later. For convenience, use IO#pipe_size instead.
698 rb_define_const(mSplice
, "F_GETPIPE_SZ",
699 UINT2NUM(F_GETPIPE_SZ
));
702 * fcntl() command constant used to set the size of a pipe.
703 * This constant is only defined when running Linux 2.6.35
704 * or later. For convenience, use IO#pipe_size= instead.
706 rb_define_const(mSplice
, "F_SETPIPE_SZ",
707 UINT2NUM(F_SETPIPE_SZ
));
710 sym_EAGAIN
= ID2SYM(rb_intern("EAGAIN"));