From 467e49e817336bf3b890cb0e7fe984a5cae2e5e7 Mon Sep 17 00:00:00 2001
From: Hugh McMaster <hugh.mcmaster@outlook.com>
Date: Tue, 5 Oct 2021 22:21:39 +1100
Subject: [PATCH] autogen.sh: Only copy submodules if building from a git
 branch.

`autogen.sh` fails if building from a standard source tarball.  Firstly, git
expects to be called in a git repository, then `copy_submodule_files`
blindly attempts to copy files.

Debian, Ubuntu, Linux Mint, and other derivatives all run `autogen.sh`
before compiling to regenerate build files.

This patch ensures that various git commands are only called and 'dlg' files
are only copied if `autogen.sh` is called from a git repository.
---
 autogen.sh | 22 ++++++++++++----------
 1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/autogen.sh b/autogen.sh
index ee9257659..8cca7c84a 100755
--- a/autogen.sh
+++ b/autogen.sh
@@ -182,17 +182,19 @@ copy_submodule_files ()
   cp $DLG_SRC_DIR/* src/dlg
 }
 
-DLG_INC_DIR=subprojects/dlg/include/dlg
-DLG_SRC_DIR=subprojects/dlg/src/dlg
+if test -d ".git"; then
+  DLG_INC_DIR=subprojects/dlg/include/dlg
+  DLG_SRC_DIR=subprojects/dlg/src/dlg
 
-if test -d "$DLG_INC_DIR"; then
-  :
-else
-  echo "Checking out submodule in \`subprojects/dlg':"
-  git submodule init
-  git submodule update
+  if test -d "$DLG_INC_DIR"; then
+    :
+  else
+    echo "Checking out submodule in \`subprojects/dlg':"
+    git submodule init
+    git submodule update
+  fi
+
+  copy_submodule_files
 fi
 
-copy_submodule_files
-
 # EOF