[newlib-cygwin] Cygwin: pty: Fix acquiring attach_mutex timing.

[Takashi Yano]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=b29fd96cac1df380d2be05892dab35888598186f

commit b29fd96cac1df380d2be05892dab35888598186f
Author: Takashi Yano <takashi.yano@nifty.ne.jp>
Date:   Sun May 8 19:45:31 2022 +0900

    Cygwin: pty: Fix acquiring attach_mutex timing.
    
    - When temporarily attaching a console, the timing of acquiring
      attach_mutex was not appropriate. This sometimes caused master
      forwarding thread to crash on Ctrl-C in Windows 7. This patch
      fixes the issue.

Diff:
---
 winsup/cygwin/fhandler_tty.cc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/winsup/cygwin/fhandler_tty.cc b/winsup/cygwin/fhandler_tty.cc
index 484bf55dc..bdde1dce6 100644
--- a/winsup/cygwin/fhandler_tty.cc
+++ b/winsup/cygwin/fhandler_tty.cc
@@ -4171,13 +4171,13 @@ DWORD
 fhandler_pty_common::attach_console_temporarily (DWORD target_pid)
 {
   DWORD resume_pid = 0;
+  acquire_attach_mutex (mutex_timeout);
   pinfo pinfo_resume (myself->ppid);
   if (pinfo_resume)
     resume_pid = pinfo_resume->dwProcessId;
   if (!resume_pid)
     resume_pid = get_console_process_id (myself->dwProcessId, false);
   bool console_exists = fhandler_console::exists ();
-  acquire_attach_mutex (mutex_timeout);
   if (!console_exists || resume_pid)
     {
       FreeConsole ();