From c361a959c98695906659cda6a44846fc06cf3741 Mon Sep 17 00:00:00 2001
From: Fred Hornsey <hornseyf@objectcomputing.com>
Date: Tue, 18 Oct 2022 03:13:13 -0500
Subject: [PATCH] Fix Configure Submodule Checkout on Windows

If doing a default build on Windows with `configure` in the Visual
Studio Developer Command Prompt and no git installed on the PATH, the
configure script's `which` function will erroneously report there is a
git command available and try, but fatally fail, to use git to get the
commit hash needed for RapidJSON.

which is erroneous because it is using `-x`, which seems to return true
for directories on Windows. There is a `Git` directory in the PATH that
Visual Studio adds that it's picking up. As a side note this actually
has a working git command in it, but since it's not on the PATH I'm not
sure if we should try to take advantage of it.
---
 configure | 21 +++++++++++++++------
 1 file changed, 15 insertions(+), 6 deletions(-)

diff --git a/configure b/configure
index 4d02defee4f..4d425a815d4 100755
--- a/configure
+++ b/configure
@@ -398,15 +398,24 @@ my %specific =
     'refpost' => '}', 'comment' => '#')
   );
 
+sub might_be_executable {
+  my $path = shift;
+  return -x $path && -f $path; # On Windows -x can return true for directories
+}
+
 sub which {
   my $file = shift;
   for my $p (File::Spec->path()) {
     next if $p eq '.';
-    if (-x "$p/$file") {
-      return "$p/$file";
-    }
-    elsif ($exeext ne '' && -x "$p/$file$exeext") {
-      return "$p/$file$exeext";
+    my $path = "$p/$file";
+    if (might_be_executable($path)) {
+      return $path;
+    }
+    elsif ($exeext ne '') {
+      $path .= $exeext;
+      if (might_be_executable($path)) {
+        return $path;
+      }
     }
   }
   return undef;
@@ -470,7 +479,7 @@ sub git_submodule_prop {
     or die("git_submodule_prop open failed: $!\nStopped");
   my $prop_value = <$fd>;
   close($fd);
-  chomp($prop_value);
+  chomp($prop_value) if (defined($prop_value));
   if (!$prop_value) {
     die("Couldn't get $full_prop_name from .gitmodules\nStopped");
   }