atexit: create skeletoncmn/atexit-skeleton

This provides a skeleton for registering rollback functions in case the caller
wants to centralise their error handling in an `atexit(3)`-like manner.

Subsystems within libgit2 will register themselves when they e.g. create
lockfiles. If the caller detects an error (potentially unrelated to the libgit2
operation) and wants to back out, they could call `git_atexit()` in order to
remove lockfiles which the library is holding.

1 files changed, 19 insertions, 0 deletions

diff --git a/include/git2/atexit.h b/include/git2/atexit.h
new file mode 100644
index 000000000..cab8e1872
--- /dev/null
+++ b/include/git2/atexit.h
@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) the libgit2 contributors. All rights reserved.
+ *
+ * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * a Linking Exception. For full terms see the included COPYING file.
+ */
+#ifndef INCLUDE_git_atexit_h__
+#define INCLUDE_git_atexit_h__
+
+#include "common.h"
+
+/**
+ * Execute cleanup for in-process operations
+ *
+ * This will e.g. delete lockfiles we own.
+ */
+GIT_EXTERN(int) git_atexit(void);
+
+#endif /* INCLUDE_git_atexit_h__ */