hash: add an SHA-256 implementation using OpenSSL

diff --git a/commit-graph.h b/commit-graph.h
index 698f09e2bc876cf9ccfed04022827dc1fdd9bfbd..b05047676514e4d031ac90de50510eb33a4b6db6 100644 (file)
--- a/commit-graph.h
+++ b/commit-graph.h
@@ -6,6 +6,8 @@
 #include "string-list.h"
 #include "cache.h"
 
+#define GIT_TEST_COMMIT_GRAPH "GIT_TEST_COMMIT_GRAPH"
+
 struct commit;
 
 char *get_commit_graph_filename(const char *obj_dir);