zip.c: Const-qualify bn

Even if basename(3) does modify the input string [1], the returned
pointer is only used as a reference in this context.

[1]: https://pubs.opengroup.org/onlinepubs/9699919799/functions/basename.html

1 files changed, 2 insertions, 1 deletions

diff --git a/zip.c b/zip.c
index 79cf833..668030c 100644
--- a/zip.c
+++ b/zip.c
@@ -257,7 +257,8 @@ int zip(const char *const dir, struct http_response *const r)
     struct cftw *c = NULL;
     ZIPstream *stream = NULL;
     struct zip *z = NULL;
-    char *basedir = NULL, *bndup = NULL, *bn = NULL;
+    char *basedir = NULL, *bndup = NULL;
+    const char *bn;
     int fds[2] = {-1, -1}, flags;
     struct dynstr d;