Fix hang when deleting a pipe process

* src/w32.h (FILE_DONT_CLOSE): New flag.
* src/w32.c (sys_close): Don't close descriptors used to read from
the pipe process.  Leave the FILE_DONT_CLOSE flag set in the
descriptor's info.
(register_aux_fd): Set the FILE_DONT_CLOSE flag in the
descriptor's info.
* src/w32proc.c (reader_thread): When exiting normally, close the
file descriptor used to read from a pipe process.  (Bug#52414)

1 files changed, 15 insertions, 6 deletions

diff --git a/src/w32proc.c b/src/w32proc.c
index 360f45e9e11..bfe720eb623 100644
--- a/src/w32proc.c
+++ b/src/w32proc.c
@@ -1206,6 +1206,7 @@ static DWORD WINAPI
 reader_thread (void *arg)
 {
   child_process *cp;
+  int fd;
 
   /* Our identity */
   cp = (child_process *)arg;
@@ -1220,12 +1221,13 @@ reader_thread (void *arg)
     {
       int rc;
 
-      if (cp->fd >= 0 && (fd_info[cp->fd].flags & FILE_CONNECT) != 0)
-        rc = _sys_wait_connect (cp->fd);
-      else if (cp->fd >= 0 && (fd_info[cp->fd].flags & FILE_LISTEN) != 0)
-        rc = _sys_wait_accept (cp->fd);
+      fd = cp->fd;
+      if (fd >= 0 && (fd_info[fd].flags & FILE_CONNECT) != 0)
+        rc = _sys_wait_connect (fd);
+      else if (fd >= 0 && (fd_info[fd].flags & FILE_LISTEN) != 0)
+        rc = _sys_wait_accept (fd);
       else
-        rc = _sys_read_ahead (cp->fd);
+        rc = _sys_read_ahead (fd);
 
       /* Don't bother waiting for the event if we already have been
          told to exit by delete_child.  */
@@ -1238,7 +1240,7 @@ reader_thread (void *arg)
         {
           DebPrint (("reader_thread.SetEvent(0x%x) failed with %lu for fd %ld (PID %d)\n",
                      (DWORD_PTR)cp->char_avail, GetLastError (),
-                     cp->fd, cp->pid));
+                     fd, cp->pid));
           return 1;
         }
 
@@ -1266,6 +1268,13 @@ reader_thread (void *arg)
       if (cp->status == STATUS_READ_ERROR)
         break;
     }
+  /* If this thread was reading from a pipe process, close the
+     descriptor used for reading, as sys_close doesn't in that case.  */
+  if (fd_info[fd].flags == FILE_DONT_CLOSE)
+    {
+      fd_info[fd].flags = 0;
+      _close (fd);
+    }
   return 0;
 }