[PATCH] externalsrc: Handle .git not being a directory

[Joshua Watt <jpewhacker@gmail.com>]

If EXTERNALSRC points to a git submodule, the .git entry will not be a
directory, but rather a file that points to the actual .git location (in
the parent repository). If this still can't be resolved to a directory,
ignore it and fall back to the non-git method for hashing.

Signed-off-by: Joshua Watt <JPEWhacker@gmail.com>
---
 meta/classes/externalsrc.bbclass | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/meta/classes/externalsrc.bbclass b/meta/classes/externalsrc.bbclass
index 9aabb426d9e..ab5cd636051 100644
--- a/meta/classes/externalsrc.bbclass
+++ b/meta/classes/externalsrc.bbclass
@@ -182,13 +182,25 @@ def srctree_hash_files(d, srcdir=None):
     import shutil
     import subprocess
     import tempfile
+    import re
 
     s_dir = srcdir or d.getVar('EXTERNALSRC')
     git_dir = os.path.join(s_dir, '.git')
+
+    if os.path.exists(git_dir) and os.path.isfile(git_dir):
+        with open(git_dir, 'r') as f:
+            m = re.match(r'gitdir: (.*)$', f.read())
+            if m is not None:
+                path = m.group(1)
+                if os.path.isabs(path):
+                    git_dir = path
+                else:
+                    git_dir = os.path.join(git_dir, path)
+
     oe_hash_file = os.path.join(git_dir, 'oe-devtool-tree-sha1')
 
     ret = " "
-    if os.path.exists(git_dir):
+    if os.path.exists(git_dir) and os.path.isdir(git_dir):
         with tempfile.NamedTemporaryFile(prefix='oe-devtool-index') as tmp_index:
             # Clone index
             shutil.copyfile(os.path.join(git_dir, 'index'), tmp_index.name)
-- 
2.13.3