From 6cc3d35eee6ec073361b7a33e19e6e0c9d54682b Mon Sep 17 00:00:00 2001
From: Kaz Kylheku <kaz@kylheku.com>
Date: Sat, 2 Jul 2016 09:57:34 -0700
Subject: Fix spawned process window not foregrounding.

This patch addresses an issue whereby the window of
a process created with CreateProcess fails to come
to the foreground.

This occurs when the calling process itself hasn't run any
Windows event processing loop. A repro test case is to make a
program with a main, and and call CreateProcess to spawn
calc.exe or notepad.exe before doing anything else.

It turns out that a dummy call to TranslateMessage makes this
issue goes away. If such a call is made before CreateProcess,
then the spawned process' window comes up in the foreground
as expected.

* winsup/cygwin/Makefile.in (DLL_IMPORTS): We need to link
in user32.dll to call TranslateMessage. Condense the
multiple ${shell ...} call repetition with a foreach.

* winsup/cygwin/spawn.cc (child_info_spawn::worker): Do the
dummy TranslateMessage call before the section of code that
calls CreateProcess or CreateProcessAsUser.
---
 winsup/cygwin/Makefile.in | 3 ++-
 winsup/cygwin/spawn.cc    | 5 +++++
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/winsup/cygwin/Makefile.in b/winsup/cygwin/Makefile.in
index 73d9b37fd..74dbca3e3 100644
--- a/winsup/cygwin/Makefile.in
+++ b/winsup/cygwin/Makefile.in
@@ -136,7 +136,8 @@ EXTRA_OFILES:=
 
 MALLOC_OFILES:=malloc.o
 
-DLL_IMPORTS:=${shell $(CC) -print-file-name=w32api/libkernel32.a} ${shell $(CC) -print-file-name=w32api/libntdll.a}
+DLL_IMPORTS:=${foreach i,kernel32 user32 ntdll,\
+		${shell $(CC) -print-file-name=w32api/lib${i}.a}}
 
 #
 LIBC_OFILES:= \
diff --git a/winsup/cygwin/spawn.cc b/winsup/cygwin/spawn.cc
index 676e5d798..a4071c986 100644
--- a/winsup/cygwin/spawn.cc
+++ b/winsup/cygwin/spawn.cc
@@ -715,6 +715,11 @@ child_info_spawn::worker (const char *prog_arg, const char *const *argv,
 
       if (!iscygwin ())
 	init_console_handler (myself->ctty > 0);
+      /* Workaround for the issue of the window of a spawned process
+	 not coming to the foreground. A useless call to TranslateMessage
+	 cures this somehow. */
+      MSG dummy = { 0 };
+      (void) TranslateMessage(&dummy);
 
     loop:
       /* When ruid != euid we create the new process under the current original
-- 
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