Fix segmentation fault in empty repository

When a repository is empty, the ATOM feed link is written in the header,
but this involves formatting ctx->qry.head which is NULL in this case.
With glibc, vsnprintf formats "%s" with a NULL input as "(null)" but on
Solaris this results in a segmentation fault.  Since we don't have a
meaningful head for the atom feed in an empty repository, it's simplest
not to write out the link element at all.

Signed-off-by: John Keeping <john@metanate.com>

1 files changed, 1 insertions, 1 deletions

@@ -619,7 +619,7 @@ void cgit_print_docstart(struct cgit_context *ctx)
                 html_attr(ctx->cfg.favicon);
                 html("'/>\n");
         }
-        if (host && ctx->repo) {
+        if (host && ctx->repo && ctx->qry.head) {
                 html("<link rel='alternate' title='Atom feed' href='");
                 html(cgit_httpscheme());
                 html_attr(cgit_hosturl());