1 files changed, 42 insertions, 0 deletions
diff --git a/utils-lib.c b/utils-lib.c
new file mode 100644
index 00000000..9d53c6e5
--- /dev/null
+++ b/utils-lib.c
@@ -0,0 +1,42 @@
+#define _GNU_SOURCE
+
+#include "kerncompat.h"
+#include <unistd.h>
+#include <stdlib.h>
+#include <limits.h>
+
+#if BTRFS_FLAT_INCLUDES
+#else
+#endif /* BTRFS_FLAT_INCLUDES */
+
+/*
+ * This function should be only used when parsing command arg, it won't return
+ * error to its caller and rather exit directly just like usage().
+ */
+u64 arg_strtou64(const char *str)
+{
+	u64 value;
+	char *ptr_parse_end = NULL;
+
+	value = strtoull(str, &ptr_parse_end, 0);
+	if (ptr_parse_end && *ptr_parse_end != '\0') {
+		fprintf(stderr, "ERROR: %s is not a valid numeric value.\n",
+			str);
+		exit(1);
+	}
+
+	/*
+	 * if we pass a negative number to strtoull, it will return an
+	 * unexpected number to us, so let's do the check ourselves.
+	 */
+	if (str[0] == '-') {
+		fprintf(stderr, "ERROR: %s: negative value is invalid.\n",
+			str);
+		exit(1);
+	}
+	if (value == ULLONG_MAX) {
+		fprintf(stderr, "ERROR: %s is too large.\n", str);
+		exit(1);
+	}
+	return value;
+}