commit 50b94353e49ddf9a453ddb8730b34dacb101880a
Author: J. Fernando Sánchez <balkian@gmail.com>
Date:   Thu Jun 14 19:33:08 2018 +0200

diff --git a/submodules2subtrees.sh b/submodules2subtrees.sh
new file mode 100644
index 0000000..947a491
--- /dev/null
+++ b/submodules2subtrees.sh
@@ -0,0 +1,42 @@
+#!/bin/bash -x
+# extract the list of submodules from .gitmodule
+cat .gitmodules |while read i
+do
+if [[ $i == \[submodule* ]]; then
+    echo converting $i
+
+    # extract the module's prefix
+    mpath=$(echo $i | cut -d\" -f2)
+
+    # skip two lines
+    read i; read i;
+
+    # extract the url of the submodule
+    murl=$(echo $i|cut -d\= -f2|xargs)
+
+    # extract the module name
+    mname=$(basename $mpath)
+
+    # deinit the module
+    git submodule deinit $mpath
+
+    # remove the module from git
+    git rm -r --cached $mpath
+
+    # remove the module from the filesystem
+    rm -rf $mpath
+
+    # commit the change
+    git commit -m "Removed $mpath submodule"
+
+    # add the remote
+    git remote add -f $mname $murl
+
+    # add the subtree
+    git subtree add --prefix $mpath $mname master --squash
+
+    # fetch the files
+    git fetch $murl master
+fi
+done
+git rm .gitmodules
\ No newline at end of file