From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2155) id CEB263858026; Tue, 14 Sep 2021 15:07:24 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org CEB263858026 Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit From: Corinna Vinschen To: cygwin-cvs@sourceware.org Subject: [newlib-cygwin] Cygwin: select: Introduce select_sem semaphore for pipe. X-Act-Checkin: newlib-cygwin X-Git-Author: Takashi Yano X-Git-Refname: refs/heads/master X-Git-Oldrev: b07660ac19f2c5be5ad51d21a969d408dfbf5744 X-Git-Newrev: 597f87294dd683be45331096fbd117148d8e1471 Message-Id: <20210914150724.CEB263858026@sourceware.org> Date: Tue, 14 Sep 2021 15:07:24 +0000 (GMT) X-BeenThere: cygwin-cvs@cygwin.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Cygwin core component git logs List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 14 Sep 2021 15:07:24 -0000 https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=597f87294dd683be45331096fbd117148d8e1471 commit 597f87294dd683be45331096fbd117148d8e1471 Author: Takashi Yano Date: Wed Sep 8 17:18:35 2021 +0900 Cygwin: select: Introduce select_sem semaphore for pipe. - This patch introduces select_sem semaphore which notifies pipe status change. Diff: --- winsup/cygwin/fhandler.cc | 1 + winsup/cygwin/fhandler.h | 3 +++ winsup/cygwin/fhandler_pipe.cc | 25 +++++++++++++++++++++++++ winsup/cygwin/select.cc | 10 ++++++++-- 4 files changed, 37 insertions(+), 2 deletions(-) diff --git a/winsup/cygwin/fhandler.cc b/winsup/cygwin/fhandler.cc index f0c1b68f1..39fe2640a 100644 --- a/winsup/cygwin/fhandler.cc +++ b/winsup/cygwin/fhandler.cc @@ -1464,6 +1464,7 @@ fhandler_base::fhandler_base () : _refcnt (0), openflags (0), unique_id (0), + select_sem (NULL), archetype (NULL), usecount (0) { diff --git a/winsup/cygwin/fhandler.h b/winsup/cygwin/fhandler.h index 7aed089eb..d309be2f7 100644 --- a/winsup/cygwin/fhandler.h +++ b/winsup/cygwin/fhandler.h @@ -217,6 +217,7 @@ class fhandler_base void set_ino (ino_t i) { ino = i; } HANDLE read_state; + HANDLE select_sem; public: LONG inc_refcnt () {return InterlockedIncrement (&_refcnt);} @@ -520,6 +521,8 @@ public: fh->copy_from (this); return fh; } + + HANDLE get_select_sem () { return select_sem; } }; struct wsa_event diff --git a/winsup/cygwin/fhandler_pipe.cc b/winsup/cygwin/fhandler_pipe.cc index c75476040..ea8ea41dd 100644 --- a/winsup/cygwin/fhandler_pipe.cc +++ b/winsup/cygwin/fhandler_pipe.cc @@ -376,6 +376,8 @@ fhandler_pipe::raw_read (void *ptr, size_t& len) } else if (status == STATUS_THREAD_CANCELED) pthread::static_cancel_self (); + if (select_sem && nbytes) + ReleaseSemaphore (select_sem, get_obj_handle_count (select_sem), NULL); len = nbytes; } @@ -507,6 +509,8 @@ fhandler_pipe_fifo::raw_write (const void *ptr, size_t len) set_errno (EINTR); else if (status == STATUS_THREAD_CANCELED) pthread::static_cancel_self (); + if (select_sem && nbytes) + ReleaseSemaphore (select_sem, get_obj_handle_count (select_sem), NULL); return nbytes ?: -1; } @@ -515,6 +519,8 @@ fhandler_pipe::fixup_after_fork (HANDLE parent) { if (read_mtx) fork_fixup (parent, read_mtx, "read_mtx"); + if (select_sem) + fork_fixup (parent, select_sem, "select_sem"); fhandler_base::fixup_after_fork (parent); } @@ -536,6 +542,15 @@ fhandler_pipe::dup (fhandler_base *child, int flags) ftp->close (); res = -1; } + else if (select_sem && + !DuplicateHandle (GetCurrentProcess (), select_sem, + GetCurrentProcess (), &ftp->select_sem, + 0, !(flags & O_CLOEXEC), DUPLICATE_SAME_ACCESS)) + { + __seterrno (); + ftp->close (); + res = -1; + } debug_printf ("res %d", res); return res; @@ -546,6 +561,11 @@ fhandler_pipe::close () { if (read_mtx) CloseHandle (read_mtx); + if (select_sem) + { + ReleaseSemaphore (select_sem, get_obj_handle_count (select_sem), NULL); + CloseHandle (select_sem); + } return fhandler_base::close (); } @@ -765,6 +785,11 @@ fhandler_pipe::create (fhandler_pipe *fhs[2], unsigned psize, int mode) fhs[0]->set_read_mutex (mtx); res = 0; } + fhs[0]->select_sem = CreateSemaphore (&sa, 0, INT32_MAX, NULL); + if (fhs[0]->select_sem) + DuplicateHandle (GetCurrentProcess (), fhs[0]->select_sem, + GetCurrentProcess (), &fhs[1]->select_sem, + 0, 1, DUPLICATE_SAME_ACCESS); } debug_printf ("%R = pipe([%p, %p], %d, %y)", res, fhs[0], fhs[1], psize, mode); diff --git a/winsup/cygwin/select.cc b/winsup/cygwin/select.cc index c85ce748c..e9e71b269 100644 --- a/winsup/cygwin/select.cc +++ b/winsup/cygwin/select.cc @@ -762,7 +762,13 @@ start_thread_pipe (select_record *me, select_stuff *stuff) { pi->start = &stuff->start; pi->stop_thread = false; - pi->bye = CreateEvent (&sec_none_nih, TRUE, FALSE, NULL); + pi->bye = me->fh->get_select_sem (); + if (pi->bye) + DuplicateHandle (GetCurrentProcess (), pi->bye, + GetCurrentProcess (), &pi->bye, + 0, 0, DUPLICATE_SAME_ACCESS); + else + pi->bye = CreateSemaphore (&sec_none_nih, 0, INT32_MAX, NULL); pi->thread = new cygthread (thread_pipe, pi, "pipesel"); me->h = *pi->thread; if (!me->h) @@ -780,7 +786,7 @@ pipe_cleanup (select_record *, select_stuff *stuff) if (pi->thread) { pi->stop_thread = true; - SetEvent (pi->bye); + ReleaseSemaphore (pi->bye, get_obj_handle_count (pi->bye), NULL); pi->thread->detach (); CloseHandle (pi->bye); }