Be prepared for empty repositories

Before this patch, cgit would segfault on repositories with no refs.

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

2 files changed, 9 insertions, 4 deletions

diff --git a/cgit.c b/cgit.c
index 8795085..cefeddf 100644
--- a/cgit.c
+++ b/cgit.c
@@ -194,67 +194,71 @@ struct refmatch {
 int find_current_ref(const char *refname, const unsigned char *sha1,
 		     int flags, void *cb_data)
 {
 	struct refmatch *info;
 
 	info = (struct refmatch *)cb_data;
 	if (!strcmp(refname, info->req_ref))
 		info->match = 1;
 	if (!info->first_ref)
 		info->first_ref = xstrdup(refname);
 	return info->match;
 }
 
 char *find_default_branch(struct cgit_repo *repo)
 {
 	struct refmatch info;
+	char *ref;
 
 	info.req_ref = repo->defbranch;
 	info.first_ref = NULL;
 	info.match = 0;
 	for_each_branch_ref(find_current_ref, &info);
 	if (info.match)
-		return info.req_ref;
+		ref = info.req_ref;
 	else
-		return info.first_ref;
+		ref = info.first_ref;
+	if (ref)
+		ref = xstrdup(ref);
+	return ref;
 }
 
 static int prepare_repo_cmd(struct cgit_context *ctx)
 {
 	char *tmp;
 	unsigned char sha1[20];
 	int nongit = 0;
 
 	setenv("GIT_DIR", ctx->repo->path, 1);
 	setup_git_directory_gently(&nongit);
 	if (nongit) {
 		ctx->page.title = fmt("%s - %s", ctx->cfg.root_title,
 				      "config error");
 		tmp = fmt("Not a git repository: '%s'", ctx->repo->path);
 		ctx->repo = NULL;
 		cgit_print_http_headers(ctx);
 		cgit_print_docstart(ctx);
 		cgit_print_pageheader(ctx);
 		cgit_print_error(tmp);
 		cgit_print_docend();
 		return 1;
 	}
 	ctx->page.title = fmt("%s - %s", ctx->repo->name, ctx->repo->desc);
 
 	if (!ctx->qry.head) {
-		ctx->qry.head = xstrdup(find_default_branch(ctx->repo));
+		ctx->qry.head = find_default_branch(ctx->repo);
 		ctx->repo->defbranch = ctx->qry.head;
 	}
 
 	if (!ctx->qry.head) {
 		cgit_print_http_headers(ctx);
 		cgit_print_docstart(ctx);
 		cgit_print_pageheader(ctx);
 		cgit_print_error("Repository seems to be empty");
 		cgit_print_docend();
 		return 1;
 	}
 
 	if (get_sha1(ctx->qry.head, sha1)) {
 		tmp = xstrdup(ctx->qry.head);
 		ctx->qry.head = ctx->repo->defbranch;
 		cgit_print_http_headers(ctx);
diff --git a/ui-shared.c b/ui-shared.c
index 209af6e..4280a70 100644
--- a/ui-shared.c
+++ b/ui-shared.c
@@ -505,33 +505,34 @@ int print_archive_ref(const char *refname, const unsigned char *sha1,
 	html_txt(strlpart(buf, 20));
 	html_link_close();
 	return 0;
 }
 
 void add_hidden_formfields(int incl_head, int incl_search, char *page)
 {
 	char *url;
 
 	if (!ctx.cfg.virtual_root) {
 		url = fmt("%s/%s", ctx.qry.repo, page);
 		if (ctx.qry.path)
 			url = fmt("%s/%s", url, ctx.qry.path);
 		html_hidden("url", url);
 	}
 
-	if (incl_head && strcmp(ctx.qry.head, ctx.repo->defbranch))
+	if (incl_head && ctx.qry.head && ctx.repo->defbranch &&
+	    strcmp(ctx.qry.head, ctx.repo->defbranch))
 		html_hidden("h", ctx.qry.head);
 
 	if (ctx.qry.sha1)
 		html_hidden("id", ctx.qry.sha1);
 	if (ctx.qry.sha2)
 		html_hidden("id2", ctx.qry.sha2);
 
 	if (incl_search) {
 		if (ctx.qry.grep)
 			html_hidden("qt", ctx.qry.grep);
 		if (ctx.qry.search)
 			html_hidden("q", ctx.qry.search);
 	}
 }
 
 char *hc(struct cgit_cmd *cmd, const char *page)