From 06bd0ef2ab50252b81344d6810378b18f49c0e9c Mon Sep 17 00:00:00 2001
From: Christopher Faylor <me@cgf.cx>
Date: Mon, 7 May 2012 15:05:56 +0000
Subject: * DevNotes: Add entry cgf-000003. * cygheap.h
 (init_cygheap::pid_handle): Delete. * dcrt0.cc
 (child_info_spawn::handle_spawn): Keep parent open if we have execed. *
 pinfo.cc (pinfo::thisproc): Remove pid_handle manipulations. (pinfo::init):
 Don't consider a reaped process to be available. * spawn.cc
 (child_info_spawn::worker): Remove pid_handle manipulations.  Make
 wr_proc_pipe and parent noninheritable when starting a program which doesn't
 use the Cygwin DLL.  Conditionally reset wr_proc_pipe to inheritable if
 CreateProcess fails.  Inject wr_proc_pipe handle into non-Cygwin process.
 Consider a non-cygwin process to be 'synced'.

---
 winsup/cygwin/spawn.cc | 42 +++++++++++++++++++++++++++++-------------
 1 file changed, 29 insertions(+), 13 deletions(-)

(limited to 'winsup/cygwin/spawn.cc')

diff --git a/winsup/cygwin/spawn.cc b/winsup/cygwin/spawn.cc
index d296597d1..8b5e382c5 100644
--- a/winsup/cygwin/spawn.cc
+++ b/winsup/cygwin/spawn.cc
@@ -517,17 +517,6 @@ child_info_spawn::worker (const char *prog_arg, const char *const *argv,
 	  myself->sendsig = NULL;
 	  reset_sendsig = true;
 	}
-      /* Save a copy of a handle to the current process around the first time we
-	 exec so that the pid will not be reused.  Why did I stop cygwin from
-	 generating its own pids again? */
-      if (::cygheap->pid_handle)
-	/* already done previously */;
-      else if (DuplicateHandle (GetCurrentProcess (), GetCurrentProcess (),
-				GetCurrentProcess (), &::cygheap->pid_handle,
-				PROCESS_QUERY_INFORMATION, TRUE, 0))
-	ProtectHandleINH (::cygheap->pid_handle);
-      else
-	system_printf ("duplicate to pid_handle failed, %E");
     }
 
   if (null_app_name)
@@ -613,6 +602,19 @@ child_info_spawn::worker (const char *prog_arg, const char *const *argv,
   else
     wr_proc_pipe = my_wr_proc_pipe;
 
+  /* Don't allow child to inherit these handles if it's not a Cygwin program.
+     wr_proc_pipe will be injected later.  parent won't be used by the child
+     so there is no reason for the child to have it open as it can confuse
+     ps into thinking that children of windows processes are all part of
+     the same "execed" process.
+     FIXME: Someday, make it so that parent is never created when starting
+     non-Cygwin processes. */
+  if (!iscygwin ())
+    {
+      SetHandleInformation (wr_proc_pipe, HANDLE_FLAG_INHERIT, 0);
+      SetHandleInformation (parent, HANDLE_FLAG_INHERIT, 0);
+    }
+
   /* When ruid != euid we create the new process under the current original
      account and impersonate in child, this way maintaining the different
      effective vs. real ids.
@@ -734,6 +736,12 @@ loop:
 	  myself->exec_sendsig = NULL;
 	}
       myself->process_state &= ~PID_NOTCYGWIN;
+      /* Reset handle inheritance to default when the execution of a non-Cygwin
+	 process fails.  Only need to do this for _P_OVERLAY since the handle will
+	 be closed otherwise.  Don't need to do this for 'parent' since it will
+         be closed in every case.  See FIXME above. */
+      if (!real_path.iscygexec () && mode == _P_OVERLAY)
+	SetHandleInformation (wr_proc_pipe, HANDLE_FLAG_INHERIT, HANDLE_FLAG_INHERIT);
       if (wr_proc_pipe == my_wr_proc_pipe)
 	wr_proc_pipe = NULL;	/* We still own it: don't nuke in destructor */
       res = -1;
@@ -755,7 +763,7 @@ loop:
     cygpid = myself->pid;
 
   /* We print the original program name here so the user can see that too.  */
-  syscall_printf ("%d = child_info_spawn::worker(%s, %.9500s)",
+  syscall_printf ("pid %d, prog_arg %s, cmd line %.9500s)",
 		  rc ? cygpid : (unsigned int) -1, prog_arg, one_line.buf);
 
   /* Name the handle similarly to proc_subproc. */
@@ -815,6 +823,12 @@ loop:
   /* Start the child running */
   if (c_flags & CREATE_SUSPENDED)
     {
+      /* Inject a non-inheritable wr_proc_pipe handle into child so that we
+	 can accurately track when the child exits without keeping this
+	 process waiting around for it to exit.  */
+      if (!iscygwin ())
+	DuplicateHandle (GetCurrentProcess (), wr_proc_pipe, pi.hProcess, NULL,
+			 0, false, DUPLICATE_SAME_ACCESS);
       ResumeThread (pi.hThread);
       if (iscygwin ())
 	strace.write_childpid (pi.dwProcessId);
@@ -827,7 +841,9 @@ loop:
   if ((mode == _P_DETACH || mode == _P_NOWAIT) && !iscygwin ())
     synced = false;
   else
-    synced = sync (pi.dwProcessId, pi.hProcess, INFINITE);
+    /* Just mark a non-cygwin process as 'synced'.  We will still eventually
+       wait for it to exit in maybe_set_exit_code_from_windows(). */
+    synced = iscygwin () ? sync (pi.dwProcessId, pi.hProcess, INFINITE) : true;
 
   switch (mode)
     {
-- 
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