[newlib-cygwin/main] Cygwin: pipe: handle signals explicitely in raw_write

[newlib-cygwin/main] Cygwin: pipe: handle signals explicitely in raw_write

[Corinna Vinschen]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=7f3c22532577ae0a926e8eb8ad63787c9841abbf

commit 7f3c22532577ae0a926e8eb8ad63787c9841abbf
Author:     Corinna Vinschen <corinna@vinschen.de>
AuthorDate: Sun Aug 18 21:40:51 2024 +0200
Commit:     Corinna Vinschen <corinna@vinschen.de>
CommitDate: Sun Aug 18 21:40:51 2024 +0200

    Cygwin: pipe: handle signals explicitely in raw_write
    
    The simple cygwait call in fhandler_pipe_fifo::raw_write doesn't
    take the SA_RESTART setting into account. Move handling the
    signal into raw_write.
    
    Fixes: 4b25687ea3ee2 ("Cygwin: fhandler_pipe: add raw_read and raw_write")
    Signed-off-by: Corinna Vinschen <corinna@vinschen.de>

Diff:
---
 winsup/cygwin/fhandler/pipe.cc | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/winsup/cygwin/fhandler/pipe.cc b/winsup/cygwin/fhandler/pipe.cc
index ae43cbc003da..ce6099d8bc52 100644
--- a/winsup/cygwin/fhandler/pipe.cc
+++ b/winsup/cygwin/fhandler/pipe.cc
@@ -498,9 +498,16 @@ fhandler_pipe_fifo::raw_write (const void *ptr, size_t len)
 				(PVOID) ptr, len1, NULL, NULL);
 	  if (status == STATUS_PENDING)
 	    {
-	      while (WAIT_TIMEOUT ==
-		     (waitret = cygwait (evt, (DWORD) 0, cw_cancel | cw_sig)))
+	      do
 		{
+		  /* To allow constant reader_closed() checking even if the
+		     signal has been set up with SA_RESTART, we're handling
+		     the signal here --> cw_sig_eintr. */
+		  waitret = cygwait (evt, (DWORD) 0, cw_cancel | cw_sig_eintr);
+		  /* Break out if no SA_RESTART. */
+		  if (waitret == WAIT_SIGNALED
+		      && !_my_tls.call_signal_handler ())
+		    break;
 		  if (reader_closed ())
 		    {
 		      CancelIo (get_handle ());
@@ -509,8 +516,10 @@ fhandler_pipe_fifo::raw_write (const void *ptr, size_t len)
 		      goto out;
 		    }
 		  else
-		    cygwait (select_sem, 10);
+		    cygwait (select_sem, 10, cw_cancel);
 		}
+	      /* Loop in case of blocking write or SA_RESTART */
+	      while (waitret == WAIT_TIMEOUT || waitret == WAIT_SIGNALED);
 	      /* If io.Status is STATUS_CANCELLED after CancelIo, IO has
 		 actually been cancelled and io.Information contains the
 		 number of bytes processed so far.