btrfs-progs: move prefixcmp to utils

Signed-off-by: David Sterba <dsterba@suse.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/help.c b/help.c
index 1afc09d3..c8bb7204 100644
--- a/help.c
+++ b/help.c
@@ -259,3 +259,13 @@ void help_command_group(const struct cmd_group *grp, int argc, char **argv)
 
 	usage_command_group(grp, full, 0);
 }
+
+int prefixcmp(const char *str, const char *prefix)
+{
+	for (; ; str++, prefix++)
+		if (!*prefix)
+			return 0;
+		else if (*str != *prefix)
+			return (unsigned char)*prefix - (unsigned char)*str;
+}
+