Rework sysread to use blocking read_internal_locktmp.

This commit is contained in:
Samuel Williams 2021-06-20 11:05:15 +12:00
parent 45e65f302b
commit fcc6fd23ec
Notes: git 2021-06-22 19:49:19 +09:00
2 changed files with 15 additions and 15 deletions

18
io.c
View File

@ -5349,30 +5349,24 @@ rb_io_sysread(int argc, VALUE *argv, VALUE io)
rb_raise(rb_eIOError, "sysread for buffered IO");
}
/*
* FIXME: removing rb_thread_wait_fd() here changes sysread semantics
* on non-blocking IOs. However, it's still currently possible
* for sysread to raise Errno::EAGAIN if another thread read()s
* the IO after we return from rb_thread_wait_fd() but before
* we call read()
*/
rb_io_wait(fptr->self, RB_INT2NUM(RUBY_IO_READABLE), Qnil);
rb_io_check_closed(fptr);
io_setstrbuf(&str, ilen);
iis.th = rb_thread_current();
iis.fd = fptr->fd;
iis.nonblock = 1; /* for historical reasons, maybe (see above) */
iis.nonblock = 0;
iis.buf = RSTRING_PTR(str);
iis.capa = ilen;
n = read_internal_locktmp(str, &iis);
if (n < 0) {
rb_sys_fail_path(fptr->pathv);
rb_sys_fail_path(fptr->pathv);
}
io_set_read_length(str, n, shrinkable);
if (n == 0 && ilen > 0) {
rb_eof_error();
rb_eof_error();
}
return str;

View File

@ -3316,11 +3316,17 @@ __END__
data = "a" * 100
with_pipe do |r,w|
th = Thread.new {r.sysread(100, buf)}
Thread.pass until th.stop?
buf.replace("")
assert_empty(buf, bug6099)
assert_equal 100, buf.bytesize
msg = /can't modify string; temporarily locked/
assert_raise_with_message(RuntimeError, msg) do
buf.replace("")
end
assert_predicate(th, :alive?)
w.write(data)
Thread.pass while th.alive?
th.join
end
assert_equal(data, buf, bug6099)