Handle missing default branch and error out on invalid branch names

When no branch is specified and the repository does not have a default branch,
use the first branch.

Also, print sensible errormessages when the repository does not contain any
branches and when invalid branchnames are specified.

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

1 files changed, 58 insertions, 4 deletions

diff --git a/cgit.c b/cgit.c
index 9ca93a7..e8acc03 100644
--- a/cgit.c
+++ b/cgit.c
@@ -45,13 +45,44 @@ static int cgit_prepare_cache(struct cacheitem *item)
         return 1;
 }
 
+struct refmatch {
+        char *req_ref;
+        char *first_ref;
+        int match;
+};
+
+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 repoinfo *repo)
+{
+        struct refmatch info;
+
+        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;
+        else
+                return info.first_ref;
+}
+
 static void cgit_print_repo_page(struct cacheitem *item)
 {
-        char *title;
+        char *title, *tmp;
         int show_search;
-
-        if (!cgit_query_head)
-                cgit_query_head = cgit_repo->defbranch;
+        unsigned char sha1[20];
 
         if (chdir(cgit_repo->path)) {
                 title = fmt("%s - %s", cgit_root_title, "Bad request");
@@ -67,6 +98,29 @@ static void cgit_print_repo_page(struct cacheitem *item)
         show_search = 0;
         setenv("GIT_DIR", cgit_repo->path, 1);
 
+        if (!cgit_query_head) {
+                cgit_query_head = xstrdup(find_default_branch(cgit_repo));
+                cgit_repo->defbranch = cgit_query_head;
+        }
+
+        if (!cgit_query_head) {
+                cgit_print_docstart(title, item);
+                cgit_print_pageheader(title, 0);
+                cgit_print_error("Repository seems to be empty");
+                cgit_print_docend();
+                return;
+        }
+
+        if (get_sha1(cgit_query_head, sha1)) {
+                tmp = xstrdup(cgit_query_head);
+                cgit_query_head = cgit_repo->defbranch;
+                cgit_print_docstart(title, item);
+                cgit_print_pageheader(title, 0);
+                cgit_print_error(fmt("Invalid branch: %s", tmp));
+                cgit_print_docend();
+                return;
+        }
+
         if ((cgit_cmd == CMD_SNAPSHOT) && cgit_repo->snapshots) {
                 cgit_print_snapshot(item, cgit_query_head, cgit_query_sha1,
                                     cgit_repobasename(cgit_repo->url),