Fix the val reading for MSG_ERROR_EXIT. Use 0-length MSG_DATA when

MSG_NOOP is not available (is both safer and supports older rsyncs).

diff --git a/io.c b/io.c
index c22b65f..11015f5 100644 (file)
--- a/io.c
+++ b/io.c
@@ -896,7 +896,7 @@ void noop_io_until_death(void)
                read_buf(iobuf.in_fd, buf, sizeof buf);
 }
 
-/* Buffer a message for the multiplexed output stream.  Is never used for MSG_DATA. */
+/* Buffer a message for the multiplexed output stream.  Is not used for (normal) MSG_DATA. */
 int send_msg(enum msgcode code, const char *buf, size_t len, int convert)
 {
        char *hdr;
@@ -958,8 +958,8 @@ int send_msg(enum msgcode code, const char *buf, size_t len, int convert)
        {
                size_t siz;
 
-               if ((pos += 4) >= iobuf.msg.size)
-                       pos -= iobuf.msg.size;
+               if ((pos += 4) == iobuf.msg.size)
+                       pos = 0;
 
                /* Handle a split copy if we wrap around the end of the circular buffer. */
                if (pos >= iobuf.msg.pos && (siz = iobuf.msg.size - pos) < len) {
@@ -1313,18 +1313,16 @@ void maybe_flush_socket(int important)
                io_flush(NORMAL_FLUSH);
 }
 
+/* This never adds new non-msg-buffer data, since we don't know the state
+ * of the raw-data buffer. */
 void maybe_send_keepalive(void)
 {
        if (time(NULL) - last_io_out >= allowed_lull) {
                if (!iobuf.msg.len && iobuf.out.len == iobuf.out_empty_len) {
-                       if (protocol_version < 29)
-                               return; /* there's nothing we can do */
                        if (protocol_version >= 30)
                                send_msg(MSG_NOOP, "", 0, 0);
-                       else {
-                               write_int(iobuf.out_fd, cur_flist->used);
-                               write_shortint(iobuf.out_fd, ITEM_IS_NEW);
-                       }
+                       else
+                               send_msg(MSG_DATA, "", 0, 0);
                }
                if (iobuf.msg.len)
                        perform_io(iobuf.msg.size - iobuf.msg.len + 1, PIO_NEED_MSGROOM);
@@ -1373,7 +1371,8 @@ static void read_a_msg(void)
                 * possible that this points off the end of the buffer, in
                 * which case the gradual reading of the input stream will
                 * cause this value to decrease and eventually become real. */
-               iobuf.raw_input_ends_before = iobuf.in.pos + msg_bytes;
+               if (msg_bytes)
+                       iobuf.raw_input_ends_before = iobuf.in.pos + msg_bytes;
                iobuf.in_multiplexed = 1;
                break;
        case MSG_STATS:
@@ -1410,9 +1409,11 @@ static void read_a_msg(void)
                }
                break;
        case MSG_NOOP:
+               if (msg_bytes != 0)
+                       goto invalid_msg;
+               iobuf.in_multiplexed = 1;
                if (am_sender)
                        maybe_send_keepalive();
-               iobuf.in_multiplexed = 1;
                break;
        case MSG_DELETED:
                if (msg_bytes >= sizeof data)
@@ -1543,23 +1544,19 @@ static void read_a_msg(void)
                                send_msg(MSG_ERROR_EXIT, "", 0, 0);
                                io_flush(FULL_FLUSH);
                        }
-                       val = 0;
-               } else {
-                       val = raw_read_int();
-                       if (protocol_version >= 31) {
-                               if (am_generator) {
-                                       if (DEBUG_GTE(EXIT, 3)) {
-                                               rprintf(FINFO, "[%s] sending MSG_ERROR_EXIT with exit_code %d\n",
-                                                       who_am_i(), val);
-                                       }
-                                       send_msg_int(MSG_ERROR_EXIT, val);
-                               } else {
-                                       if (DEBUG_GTE(EXIT, 3)) {
-                                               rprintf(FINFO, "[%s] sending MSG_ERROR_EXIT (len 0)\n",
-                                                       who_am_i());
-                                       }
-                                       send_msg(MSG_ERROR_EXIT, "", 0, 0);
+               } else if (protocol_version >= 31) {
+                       if (am_generator) {
+                               if (DEBUG_GTE(EXIT, 3)) {
+                                       rprintf(FINFO, "[%s] sending MSG_ERROR_EXIT with exit_code %d\n",
+                                               who_am_i(), val);
+                               }
+                               send_msg_int(MSG_ERROR_EXIT, val);
+                       } else {
+                               if (DEBUG_GTE(EXIT, 3)) {
+                                       rprintf(FINFO, "[%s] sending MSG_ERROR_EXIT (len 0)\n",
+                                               who_am_i());
                                }
+                               send_msg(MSG_ERROR_EXIT, "", 0, 0);
                        }
                }
                /* Send a negative linenum so that we don't end up