From f33635ae607660c3248aafdf8a53e926d41ae45b Mon Sep 17 00:00:00 2001
From: Corinna Vinschen <corinna@vinschen.de>
Date: Fri, 28 Oct 2022 12:24:13 +0200
Subject: [PATCH] Cygwin: spawn: drop special handling for cmd.exe and
 command.com

Apparently at one point handling cmd.exe and command.com special
made sense, but what that should be has never been documented.
There's also no clear reason why cmd.exe is different from any
other native executable.  Additionaly, checking for command.com
is entirely useless on 64 bit Windows anyway.

Just drop this code.

Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
---
 winsup/cygwin/spawn.cc | 120 ++++++++++++++++-------------------------
 1 file changed, 47 insertions(+), 73 deletions(-)

diff --git a/winsup/cygwin/spawn.cc b/winsup/cygwin/spawn.cc
index 4fc842a2b..a450ea443 100644
--- a/winsup/cygwin/spawn.cc
+++ b/winsup/cygwin/spawn.cc
@@ -345,7 +345,6 @@ child_info_spawn::worker (const char *prog_arg, const char *const *argv,
   PWCHAR runpath = tp.w_get ();
   int c_flags;
 
-  bool null_app_name = false;
   STARTUPINFOW si = {};
   int looped = 0;
 
@@ -397,47 +396,27 @@ child_info_spawn::worker (const char *prog_arg, const char *const *argv,
 	  __leave;
 	}
 
-      if (ac == 3 && argv[1][0] == '/' && tolower (argv[1][1]) == 'c' &&
-	  (iscmd (argv[0], "command.com") || iscmd (argv[0], "cmd.exe")))
+      if (real_path.iscygexec ())
 	{
-	  real_path.check (prog_arg);
-	  cmd.add ("\"");
-	  if (!real_path.error)
-	    cmd.add (real_path.get_win32 ());
-	  else
-	    cmd.add (argv[0]);
-	  cmd.add ("\"");
-	  cmd.add (" ");
-	  cmd.add (argv[1]);
-	  cmd.add (" ");
-	  cmd.add (argv[2]);
-	  real_path.set_path (argv[0]);
-	  null_app_name = true;
+	  moreinfo->argc = newargv.argc;
+	  moreinfo->argv = newargv;
 	}
+      if ((wincmdln || !real_path.iscygexec ())
+	   && !cmd.fromargv (newargv, real_path.get_win32 (),
+			     real_path.iscygexec ()))
+	{
+	  res = -1;
+	  __leave;
+	}
+
+
+      if (mode != _P_OVERLAY || !real_path.iscygexec ()
+	  || !DuplicateHandle (GetCurrentProcess (), myself.shared_handle (),
+			       GetCurrentProcess (), &moreinfo->myself_pinfo,
+			       0, TRUE, DUPLICATE_SAME_ACCESS))
+	moreinfo->myself_pinfo = NULL;
       else
-	{
-	  if (real_path.iscygexec ())
-	    {
-	      moreinfo->argc = newargv.argc;
-	      moreinfo->argv = newargv;
-	    }
-	  if ((wincmdln || !real_path.iscygexec ())
-	       && !cmd.fromargv (newargv, real_path.get_win32 (),
-				 real_path.iscygexec ()))
-	    {
-	      res = -1;
-	      __leave;
-	    }
-
-
-	  if (mode != _P_OVERLAY || !real_path.iscygexec ()
-	      || !DuplicateHandle (GetCurrentProcess (), myself.shared_handle (),
-				   GetCurrentProcess (), &moreinfo->myself_pinfo,
-				   0, TRUE, DUPLICATE_SAME_ACCESS))
-	    moreinfo->myself_pinfo = NULL;
-	  else
-	    VerifyHandle (moreinfo->myself_pinfo);
-	}
+	VerifyHandle (moreinfo->myself_pinfo);
 
       PROCESS_INFORMATION pi;
       pi.hProcess = pi.hThread = NULL;
@@ -507,42 +486,37 @@ child_info_spawn::worker (const char *prog_arg, const char *const *argv,
 	    }
 	}
 
-      if (null_app_name)
-	runpath = NULL;
+      USHORT len = real_path.get_nt_native_path ()->Length / sizeof (WCHAR);
+      if (RtlEqualUnicodePathPrefix (real_path.get_nt_native_path (),
+				     &ro_u_natp, FALSE))
+	{
+	  runpath = real_path.get_wide_win32_path (runpath);
+	  /* If the executable path length is < MAX_PATH, make sure the long
+	     path win32 prefix is removed from the path to make subsequent
+	     not long path aware native Win32 child processes happy. */
+	  if (len < MAX_PATH + 4)
+	    {
+	      if (runpath[5] == ':')
+		runpath += 4;
+	      else if (len < MAX_PATH + 6)
+		*(runpath += 6) = L'\\';
+	    }
+	}
+      else if (len < NT_MAX_PATH - ro_u_globalroot.Length / sizeof (WCHAR))
+	{
+	  UNICODE_STRING rpath;
+
+	  RtlInitEmptyUnicodeString (&rpath, runpath,
+				     (NT_MAX_PATH - 1) * sizeof (WCHAR));
+	  RtlCopyUnicodeString (&rpath, &ro_u_globalroot);
+	  RtlAppendUnicodeStringToString (&rpath,
+					  real_path.get_nt_native_path ());
+	}
       else
 	{
-	  USHORT len = real_path.get_nt_native_path ()->Length / sizeof (WCHAR);
-	  if (RtlEqualUnicodePathPrefix (real_path.get_nt_native_path (),
-					 &ro_u_natp, FALSE))
-	    {
-	      runpath = real_path.get_wide_win32_path (runpath);
-	      /* If the executable path length is < MAX_PATH, make sure the long
-		 path win32 prefix is removed from the path to make subsequent
-		 not long path aware native Win32 child processes happy. */
-	      if (len < MAX_PATH + 4)
-		{
-		  if (runpath[5] == ':')
-		    runpath += 4;
-		  else if (len < MAX_PATH + 6)
-		    *(runpath += 6) = L'\\';
-		}
-	    }
-	  else if (len < NT_MAX_PATH - ro_u_globalroot.Length / sizeof (WCHAR))
-	    {
-	      UNICODE_STRING rpath;
-
-	      RtlInitEmptyUnicodeString (&rpath, runpath,
-					 (NT_MAX_PATH - 1) * sizeof (WCHAR));
-	      RtlCopyUnicodeString (&rpath, &ro_u_globalroot);
-	      RtlAppendUnicodeStringToString (&rpath,
-					      real_path.get_nt_native_path ());
-	    }
-	  else
-	    {
-	      set_errno (ENAMETOOLONG);
-	      res = -1;
-	      __leave;
-	    }
+	  set_errno (ENAMETOOLONG);
+	  res = -1;
+	  __leave;
 	}
 
       cygbench ("spawn-worker");