1 files changed, 116 insertions, 0 deletions
diff --git a/lib/ext2fs/atexit.c b/lib/ext2fs/atexit.c
new file mode 100644
index 0000000..b3be1d5
--- /dev/null
+++ b/lib/ext2fs/atexit.c
@@ -0,0 +1,116 @@
+/*
+ * atexit.c --- Clean things up when we exit normally.
+ *
+ * Copyright Oracle, 2014
+ * Author Darrick J. Wong <darrick.wong@oracle.com>
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the GNU Library
+ * General Public License, version 2.
+ * %End-Header%
+ */
+
+#ifndef _LARGEFILE_SOURCE
+#define _LARGEFILE_SOURCE
+#endif
+#ifndef _LARGEFILE64_SOURCE
+#define _LARGEFILE64_SOURCE
+#endif
+
+#include "config.h"
+#include <stdlib.h>
+
+#include "ext2_fs.h"
+#include "ext2fs.h"
+#include "ext2fsP.h"
+
+struct exit_data {
+	ext2_exit_fn func;
+	void *data;
+};
+
+static struct exit_data *items;
+static size_t nr_items;
+
+static void handle_exit(void)
+{
+	struct exit_data *ed;
+
+	for (ed = items + nr_items - 1; ed >= items; ed--) {
+		if (ed->func == NULL)
+			continue;
+		ed->func(ed->data);
+	}
+
+	ext2fs_free_mem(&items);
+	nr_items = 0;
+}
+
+/*
+ * Schedule a function to be called at (normal) program termination.
+ * If you want this to be called during a signal exit, you must capture
+ * the signal and call exit() yourself!
+ */
+errcode_t ext2fs_add_exit_fn(ext2_exit_fn func, void *data)
+{
+	struct exit_data *ed, *free_ed = NULL;
+	size_t x;
+	errcode_t ret;
+
+	if (func == NULL)
+		return EXT2_ET_INVALID_ARGUMENT;
+
+	for (x = 0, ed = items; x < nr_items; x++, ed++) {
+		if (ed->func == func && ed->data == data)
+			return EXT2_ET_FILE_EXISTS;
+		if (ed->func == NULL)
+			free_ed = ed;
+	}
+
+	if (free_ed) {
+		free_ed->func = func;
+		free_ed->data = data;
+		return 0;
+	}
+
+	if (nr_items == 0) {
+		ret = atexit(handle_exit);
+		if (ret)
+			return ret;
+	}
+
+	ret = ext2fs_resize_mem(0, (nr_items + 1) * sizeof(struct exit_data),
+				&items);
+	if (ret)
+		return ret;
+
+	items[nr_items].func = func;
+	items[nr_items].data = data;
+	nr_items++;
+
+	return 0;
+}
+
+/* Remove a function from the exit cleanup list. */
+errcode_t ext2fs_remove_exit_fn(ext2_exit_fn func, void *data)
+{
+	struct exit_data *ed;
+	size_t x;
+
+	if (func == NULL)
+		return EXT2_ET_INVALID_ARGUMENT;
+
+	for (x = 0, ed = items; x < nr_items; x++, ed++) {
+		if (ed->func == NULL)
+			return 0;
+		if (ed->func == func && ed->data == data) {
+			size_t sz = (nr_items - (x + 1)) *
+				    sizeof(struct exit_data);
+			memmove(ed, ed + 1, sz);
+			memset(items + nr_items - 1, 0,
+			       sizeof(struct exit_data));
+		}
+	}
+
+	return 0;
+}