+ if (header) {
+ const char *fmt = "%s";
+ if (diff_output_format == DIFF_FORMAT_MACHINE)
+ fmt = "%s%c";
+
+ printf(fmt, header, 0);
+ header = NULL;
+ }
+ diff_flush(diff_output_format, 1);
+ return 1;
+}
+
+static int diff_tree_sha1_top(const unsigned char *old,
+ const unsigned char *new, const char *base)
+{
+ int ret;
+
+ call_diff_setup();
+ ret = diff_tree_sha1(old, new, base);
+ call_diff_flush();
+ return ret;
+}
+
+static int diff_root_tree(const unsigned char *new, const char *base)
+{
+ int retval;
+ void *tree;
+ unsigned long size;
+
+ call_diff_setup();
+ tree = read_object_with_reference(new, "tree", &size, NULL);
+ if (!tree)
+ die("unable to read root tree (%s)", sha1_to_hex(new));
+ retval = diff_tree("", 0, tree, size, base);
+ free(tree);
+ call_diff_flush();
+ return retval;
+}
+
+static char *generate_header(const char *commit, const char *parent, const char *msg, unsigned long len)
+{
+ static char this_header[16384];
+ int offset;
+
+ offset = sprintf(this_header, "%s%s (from %s)\n", header_prefix, commit, parent);
+ if (verbose_header) {
+ offset += pretty_print_commit(msg, len, this_header + offset, sizeof(this_header) - offset);
+ this_header[offset++] = '\n';
+ this_header[offset++] = 0;
+ }
+
+ return this_header;
+}
+
+static int diff_tree_commit(const unsigned char *commit, const char *name)
+{
+ unsigned long size, offset;
+ char *buf = read_object_with_reference(commit, "commit", &size, NULL);
+