+struct output_state {
+ char buffer[8193];
+ int used;
+ unsigned packfile_uris_started : 1;
+ unsigned packfile_started : 1;
+};
+
+static int relay_pack_data(int pack_objects_out, struct output_state *os,
+ int use_sideband, int write_packfile_line)
+{
+ /*
+ * We keep the last byte to ourselves
+ * in case we detect broken rev-list, so that we
+ * can leave the stream corrupted. This is
+ * unfortunate -- unpack-objects would happily
+ * accept a valid packdata with trailing garbage,
+ * so appending garbage after we pass all the
+ * pack data is not good enough to signal
+ * breakage to downstream.
+ */
+ ssize_t readsz;
+
+ readsz = xread(pack_objects_out, os->buffer + os->used,
+ sizeof(os->buffer) - os->used);
+ if (readsz < 0) {
+ return readsz;
+ }
+ os->used += readsz;
+
+ while (!os->packfile_started) {
+ char *p;
+ if (os->used >= 4 && !memcmp(os->buffer, "PACK", 4)) {
+ os->packfile_started = 1;
+ if (write_packfile_line) {
+ if (os->packfile_uris_started)
+ packet_delim(1);
+ packet_write_fmt(1, "\1packfile\n");
+ }
+ break;
+ }
+ if ((p = memchr(os->buffer, '\n', os->used))) {
+ if (!os->packfile_uris_started) {
+ os->packfile_uris_started = 1;
+ if (!write_packfile_line)
+ BUG("packfile_uris requires sideband-all");
+ packet_write_fmt(1, "\1packfile-uris\n");
+ }
+ *p = '\0';
+ packet_write_fmt(1, "\1%s\n", os->buffer);
+
+ os->used -= p - os->buffer + 1;
+ memmove(os->buffer, p + 1, os->used);
+ } else {
+ /*
+ * Incomplete line.
+ */
+ return readsz;
+ }
+ }
+
+ if (os->used > 1) {
+ send_client_data(1, os->buffer, os->used - 1, use_sideband);
+ os->buffer[0] = os->buffer[os->used - 1];
+ os->used = 1;
+ } else {
+ send_client_data(1, os->buffer, os->used, use_sideband);
+ os->used = 0;
+ }
+
+ return readsz;
+}
+
+static void create_pack_file(struct upload_pack_data *pack_data,
+ const struct string_list *uri_protocols)