ui-snapshot: avoid segfault when no filename is specified

Signed-off-by: Lars Hjemli <hjemli@gmail.com>

diff --git a/ui-snapshot.c b/ui-snapshot.c
index f25613e9d6c98530e48c1814305000d22ebbb44f..5372f5d3d8b42a474713fe0867f4b50d96f5acf1 100644 (file)
--- a/ui-snapshot.c
+++ b/ui-snapshot.c
@@ -156,20 +156,31 @@ static const char *get_ref_from_filename(const char *url, const char *filename,
        return NULL;
 }
 
+void show_error(char *msg)
+{
+       ctx.page.mimetype = "text/html";
+       cgit_print_http_headers(&ctx);
+       cgit_print_docstart(&ctx);
+       cgit_print_pageheader(&ctx);
+       cgit_print_error(msg);
+       cgit_print_docend();
+}
+
 void cgit_print_snapshot(const char *head, const char *hex,
                         const char *filename, int snapshots, int dwim)
 {
        const struct cgit_snapshot_format* f;
        char *prefix = NULL;
 
+       if (!filename) {
+               show_error("No snapshot name specified");
+               return;
+       }
+
        f = get_format(filename);
        if (!f) {
-               ctx.page.mimetype = "text/html";
-               cgit_print_http_headers(&ctx);
-               cgit_print_docstart(&ctx);
-               cgit_print_pageheader(&ctx);
-               cgit_print_error(fmt("Unsupported snapshot format: %s", filename));
-               cgit_print_docend();
+               show_error(xstrdup(fmt("Unsupported snapshot format: %s",
+                                      filename)));
                return;
        }