1 files changed, 31 insertions, 33 deletions

diff --git a/ui-diff.c b/ui-diff.c
index 5c864d9..a76a234 100644
--- a/ui-diff.c
+++ b/ui-diff.c
@@ -89,54 +89,52 @@ static void filepair_cb(struct diff_filepair *pair)
                 cgit_print_error("Error running diff");
 }
 
-void cgit_print_diff(const char *head, const char *old_hex, const char *new_hex, char *path)
+void cgit_print_diff(const char *new_rev, const char *old_rev)
 {
         unsigned char sha1[20], sha2[20];
         enum object_type type;
         unsigned long size;
-        struct commit *commit;
+        struct commit *commit, *commit2;
 
-        html("<table class='diff'>");
-        html("<tr><td>");
-
-        if (head && !old_hex && !new_hex) {
-                get_sha1(head, sha1);
-                commit = lookup_commit_reference(sha1);
-                if (commit && !parse_commit(commit))
-                        cgit_diff_commit(commit, filepair_cb);
-                else
-                        cgit_print_error(fmt("Bad commit: %s", head));
-                html("</td></tr>");
-                html("</table>");
+        if (!new_rev)
+                new_rev = cgit_query_head;
+        get_sha1(new_rev, sha1);
+        type = sha1_object_info(sha1, &size);
+        if (type == OBJ_BAD) {
+                cgit_print_error(fmt("Bad object name: %s", new_rev));
+                return;
+        }
+        if (type != OBJ_COMMIT) {
+                cgit_print_error(fmt("Unhandled object type: %s",
+                                     typename(type)));
                 return;
         }
 
-        get_sha1(old_hex, sha1);
-        get_sha1(new_hex, sha2);
+        commit = lookup_commit_reference(sha1);
+        if (!commit || parse_commit(commit))
+                cgit_print_error(fmt("Bad commit: %s", sha1_to_hex(sha1)));
 
-        type = sha1_object_info(sha1, &size);
-        if (type == OBJ_BAD) {
+        if (old_rev)
+                get_sha1(old_rev, sha2);
+        else if (commit->parents && commit->parents->item)
+                hashcpy(sha2, commit->parents->item->object.sha1);
+        else
+                hashclr(sha2);
+
+        if (!is_null_sha1(sha2)) {
                 type = sha1_object_info(sha2, &size);
                 if (type == OBJ_BAD) {
-                        cgit_print_error(fmt("Bad object names: %s, %s", old_hex, new_hex));
+                        cgit_print_error(fmt("Bad object name: %s", sha1_to_hex(sha2)));
                         return;
                 }
+                commit2 = lookup_commit_reference(sha2);
+                if (!commit2 || parse_commit(commit2))
+                        cgit_print_error(fmt("Bad commit: %s", sha1_to_hex(sha2)));
         }
 
-        switch(type) {
-        case OBJ_BLOB:
-                header(sha1, path, 0644, sha2, path, 0644);
-                if (cgit_diff_files(sha1, sha2, print_line))
-                        cgit_print_error("Error running diff");
-                break;
-        case OBJ_TREE:
-                cgit_diff_tree(sha1, sha2, filepair_cb);
-                break;
-        default:
-                cgit_print_error(fmt("Unhandled object type: %s",
-                                     typename(type)));
-                break;
-        }
+        html("<table class='diff'>");
+        html("<tr><td>");
+        cgit_diff_tree(sha2, sha1, filepair_cb);
         html("</td></tr>");
         html("</table>");
 }