static bool netplay_get_cmd(netplay_t *netplay)
{
uint32_t cmd;
uint32_t flip_frame;
uint32_t cmd_size;
/* FIXME: This depends on delta_frame_ready */
netplay->timeout_cnt = 0;
if (!socket_receive_all_blocking(netplay->fd, &cmd, sizeof(cmd)))
return false;
cmd = ntohl(cmd);
if (!socket_receive_all_blocking(netplay->fd, &cmd_size, sizeof(cmd)))
return false;
cmd_size = ntohl(cmd_size);
switch (cmd)
{
case NETPLAY_CMD_ACK:
/* Why are we even bothering? */
return true;
case NETPLAY_CMD_NAK:
/* Disconnect now! */
return false;
case NETPLAY_CMD_INPUT:
{
uint32_t buffer[WORDS_PER_FRAME];
unsigned i;
if (cmd_size != WORDS_PER_FRAME * sizeof(uint32_t))
{
RARCH_ERR("NETPLAY_CMD_INPUT received an unexpected payload size.\n");
return netplay_cmd_nak(netplay);
}
if (!socket_receive_all_blocking(netplay->fd, buffer, sizeof(buffer)))
{
RARCH_ERR("Failed to receive NETPLAY_CMD_INPUT input.\n");
return netplay_cmd_nak(netplay);
}
for (i = 0; i < WORDS_PER_FRAME; i++)
buffer[i] = ntohl(buffer[i]);
if (buffer[0] < netplay->read_frame_count)
{
/* We already had this, so ignore the new transmission */
return true;
}
else if (buffer[0] > netplay->read_frame_count)
{
/* Out of order = out of luck */
return netplay_cmd_nak(netplay);
}
/* The data's good! */
netplay->buffer[netplay->read_ptr].have_remote = true;
memcpy(netplay->buffer[netplay->read_ptr].real_input_state,
buffer + 1, sizeof(buffer) - sizeof(uint32_t));
netplay->read_ptr = NEXT_PTR(netplay->read_ptr);
netplay->read_frame_count++;
return true;
}
case NETPLAY_CMD_FLIP_PLAYERS:
if (cmd_size != sizeof(uint32_t))
{
RARCH_ERR("CMD_FLIP_PLAYERS received an unexpected command size.\n");
return netplay_cmd_nak(netplay);
}
if (!socket_receive_all_blocking(
netplay->fd, &flip_frame, sizeof(flip_frame)))
{
RARCH_ERR("Failed to receive CMD_FLIP_PLAYERS argument.\n");
return netplay_cmd_nak(netplay);
}
flip_frame = ntohl(flip_frame);
if (flip_frame < netplay->read_frame_count)
{
RARCH_ERR("Host asked us to flip users in the past. Not possible ...\n");
return netplay_cmd_nak(netplay);
}
netplay->flip ^= true;
netplay->flip_frame = flip_frame;
/* Force a rewind to assure the flip happens: This just prevents us
* from skipping other past the flip because our prediction was
* correct */
if (flip_frame < netplay->self_frame_count)
netplay->force_rewind = true;
RARCH_LOG("Netplay users are flipped.\n");
runloop_msg_queue_push("Netplay users are flipped.", 1, 180, false);
return true;
case NETPLAY_CMD_SPECTATE:
RARCH_ERR("NETPLAY_CMD_SPECTATE unimplemented.\n");
return netplay_cmd_nak(netplay);
case NETPLAY_CMD_DISCONNECT:
hangup(netplay);
return true;
case NETPLAY_CMD_CRC:
{
uint32_t buffer[2];
size_t tmp_ptr = netplay->self_ptr;
bool found = false;
if (cmd_size != sizeof(buffer))
{
RARCH_ERR("NETPLAY_CMD_CRC received unexpected payload size.\n");
return netplay_cmd_nak(netplay);
}
if (!socket_receive_all_blocking(netplay->fd, buffer, sizeof(buffer)))
{
RARCH_ERR("NETPLAY_CMD_CRC failed to receive payload.\n");
return netplay_cmd_nak(netplay);
}
buffer[0] = ntohl(buffer[0]);
buffer[1] = ntohl(buffer[1]);
/* Received a CRC for some frame. If we still have it, check if it
* matched. This approach could be improved with some quick modular
* arithmetic. */
do
{
if ( netplay->buffer[tmp_ptr].used
&& netplay->buffer[tmp_ptr].frame == buffer[0])
{
found = true;
break;
}
tmp_ptr = PREV_PTR(tmp_ptr);
} while (tmp_ptr != netplay->self_ptr);
if (!found)
{
/* Oh well, we got rid of it! */
return true;
}
if (buffer[0] <= netplay->other_frame_count)
{
/* We've already replayed up to this frame, so we can check it
* directly */
uint32_t local_crc = netplay_delta_frame_crc(
netplay, &netplay->buffer[tmp_ptr]);
if (buffer[1] != local_crc)
{
/* Problem! */
netplay_cmd_request_savestate(netplay);
}
}
else
{
/* We'll have to check it when we catch up */
netplay->buffer[tmp_ptr].crc = buffer[1];
}
return true;
}
case NETPLAY_CMD_REQUEST_SAVESTATE:
/* Delay until next frame so we don't send the savestate after the
* input */
netplay->force_send_savestate = true;
return true;
case NETPLAY_CMD_LOAD_SAVESTATE:
{
uint32_t frame;
/* Make sure we're ready for it */
if (netplay->quirks & NETPLAY_QUIRK_INITIALIZATION)
{
if (!netplay->is_replay)
{
netplay->is_replay = true;
netplay->replay_ptr = netplay->self_ptr;
netplay->replay_frame_count = netplay->self_frame_count;
netplay_wait_and_init_serialization(netplay);
netplay->is_replay = false;
}
else
{
netplay_wait_and_init_serialization(netplay);
}
}
/* There is a subtlty in whether the load comes before or after the
* current frame:
*
* If it comes before the current frame, then we need to force a
* rewind to that point.
*
* If it comes after the current frame, we need to jump ahead, then
* (strangely) force a rewind to the frame we're already on, so it
* gets loaded. This is just to avoid having reloading implemented in
* too many places. */
if (cmd_size > netplay->state_size + sizeof(uint32_t))
{
RARCH_ERR("CMD_LOAD_SAVESTATE received an unexpected save state size.\n");
return netplay_cmd_nak(netplay);
}
if (!socket_receive_all_blocking(netplay->fd, &frame, sizeof(frame)))
{
RARCH_ERR("CMD_LOAD_SAVESTATE failed to receive savestate frame.\n");
return netplay_cmd_nak(netplay);
}
frame = ntohl(frame);
if (frame != netplay->read_frame_count)
{
RARCH_ERR("CMD_LOAD_SAVESTATE loading a state out of order!\n");
return netplay_cmd_nak(netplay);
}
if (!socket_receive_all_blocking(netplay->fd,
netplay->buffer[netplay->read_ptr].state,
cmd_size - sizeof(uint32_t)))
{
RARCH_ERR("CMD_LOAD_SAVESTATE failed to receive savestate.\n");
return netplay_cmd_nak(netplay);
}
/* Skip ahead if it's past where we are */
if (frame > netplay->self_frame_count)
{
/* This is squirrely: We need to assure that when we advance the
* frame in post_frame, THEN we're referring to the frame to
* load into. If we refer directly to read_ptr, then we'll end
* up never reading the input for read_frame_count itself, which
* will make the other side unhappy. */
netplay->self_ptr = PREV_PTR(netplay->read_ptr);
netplay->self_frame_count = frame - 1;
}
/* And force rewind to it */
netplay->force_rewind = true;
netplay->savestate_request_outstanding = false;
netplay->other_ptr = netplay->read_ptr;
netplay->other_frame_count = frame;
return true;
}
case NETPLAY_CMD_PAUSE:
netplay->remote_paused = true;
return true;
case NETPLAY_CMD_RESUME:
netplay->remote_paused = false;
return true;
default:
break;
}
RARCH_ERR("Unknown netplay command received.\n");
return netplay_cmd_nak(netplay);
}
/**
* netplay_net_post_frame:
* @netplay : pointer to netplay object
*
* Post-frame for Netplay (normal version).
* We check if we have new input and replay from recorded input.
**/
static void netplay_net_post_frame(netplay_t *netplay)
{
netplay->self_ptr = NEXT_PTR(netplay->self_ptr);
netplay->self_frame_count++;
/* Only relevant if we're connected */
if (!netplay->has_connection)
{
netplay->read_frame_count = netplay->other_frame_count = netplay->self_frame_count;
netplay->read_ptr = netplay->other_ptr = netplay->self_ptr;
return;
}
#ifndef DEBUG_NONDETERMINISTIC_CORES
if (!netplay->force_rewind)
{
/* Skip ahead if we predicted correctly.
* Skip until our simulation failed. */
while (netplay->other_frame_count < netplay->read_frame_count &&
netplay->other_frame_count < netplay->self_frame_count)
{
struct delta_frame *ptr = &netplay->buffer[netplay->other_ptr];
if (memcmp(ptr->simulated_input_state, ptr->real_input_state,
sizeof(ptr->real_input_state)) != 0
&& !ptr->used_real)
break;
netplay_handle_frame_hash(netplay, ptr);
netplay->other_ptr = NEXT_PTR(netplay->other_ptr);
netplay->other_frame_count++;
}
}
#endif
/* Now replay the real input if we've gotten ahead of it */
if (netplay->force_rewind ||
(netplay->other_frame_count < netplay->read_frame_count &&
netplay->other_frame_count < netplay->self_frame_count))
{
retro_ctx_serialize_info_t serial_info;
/* Replay frames. */
netplay->is_replay = true;
netplay->replay_ptr = netplay->other_ptr;
netplay->replay_frame_count = netplay->other_frame_count;
if (netplay->quirks & NETPLAY_QUIRK_INITIALIZATION)
/* Make sure we're initialized before we start loading things */
netplay_wait_and_init_serialization(netplay);
serial_info.data = NULL;
serial_info.data_const = netplay->buffer[netplay->replay_ptr].state;
serial_info.size = netplay->state_size;
if (!core_unserialize(&serial_info))
{
RARCH_ERR("Netplay savestate loading failed: Prepare for desync!\n");
}
while (netplay->replay_frame_count < netplay->self_frame_count)
{
struct delta_frame *ptr = &netplay->buffer[netplay->replay_ptr];
serial_info.data = ptr->state;
serial_info.size = netplay->state_size;
serial_info.data_const = NULL;
/* Remember the current state */
memset(serial_info.data, 0, serial_info.size);
core_serialize(&serial_info);
if (netplay->replay_frame_count < netplay->read_frame_count)
netplay_handle_frame_hash(netplay, ptr);
/* Simulate this frame's input */
if (netplay->replay_frame_count >= netplay->read_frame_count)
netplay_simulate_input(netplay, netplay->replay_ptr);
autosave_lock();
core_run();
autosave_unlock();
netplay->replay_ptr = NEXT_PTR(netplay->replay_ptr);
netplay->replay_frame_count++;
#ifdef DEBUG_NONDETERMINISTIC_CORES
if (ptr->have_remote && netplay_delta_frame_ready(netplay, &netplay->buffer[netplay->replay_ptr], netplay->replay_frame_count))
{
RARCH_LOG("PRE %u: %X\n", netplay->replay_frame_count-1, netplay_delta_frame_crc(netplay, ptr));
if (netplay->is_server)
RARCH_LOG("INP %X %X\n", ptr->real_input_state[0], ptr->self_state[0]);
else
RARCH_LOG("INP %X %X\n", ptr->self_state[0], ptr->real_input_state[0]);
ptr = &netplay->buffer[netplay->replay_ptr];
serial_info.data = ptr->state;
memset(serial_info.data, 0, serial_info.size);
core_serialize(&serial_info);
RARCH_LOG("POST %u: %X\n", netplay->replay_frame_count-1, netplay_delta_frame_crc(netplay, ptr));
}
#endif
}
if (netplay->read_frame_count < netplay->self_frame_count)
{
netplay->other_ptr = netplay->read_ptr;
netplay->other_frame_count = netplay->read_frame_count;
}
else
{
netplay->other_ptr = netplay->self_ptr;
netplay->other_frame_count = netplay->self_frame_count;
}
netplay->is_replay = false;
netplay->force_rewind = false;
}
/* If we're supposed to stall, rewind (we shouldn't get this far if we're
* stalled, so this is a last resort) */
if (netplay->stall)
{
retro_ctx_serialize_info_t serial_info;
netplay->self_ptr = PREV_PTR(netplay->self_ptr);
netplay->self_frame_count--;
serial_info.data = NULL;
serial_info.data_const = netplay->buffer[netplay->self_ptr].state;
serial_info.size = netplay->state_size;
core_unserialize(&serial_info);
}
}
/**
* netplay_sync_post_frame
* @netplay : pointer to netplay object
*
* Post-frame for Netplay synchronization.
* We check if we have new input and replay from recorded input.
*/
void netplay_sync_post_frame(netplay_t *netplay, bool stalled)
{
uint32_t lo_frame_count, hi_frame_count;
/* Unless we're stalling, we've just finished running a frame */
if (!stalled)
{
netplay->run_ptr = NEXT_PTR(netplay->run_ptr);
netplay->run_frame_count++;
}
/* We've finished an input frame even if we're stalling */
if ((!stalled || netplay->stall == NETPLAY_STALL_INPUT_LATENCY) &&
netplay->self_frame_count < netplay->run_frame_count + netplay->input_latency_frames)
{
netplay->self_ptr = NEXT_PTR(netplay->self_ptr);
netplay->self_frame_count++;
}
/* Only relevant if we're connected and not in a desynching operation */
if ((netplay->is_server && !netplay->connected_players) ||
(netplay->self_mode < NETPLAY_CONNECTION_CONNECTED) ||
(netplay->desync))
{
netplay->other_frame_count = netplay->self_frame_count;
netplay->other_ptr = netplay->self_ptr;
/* FIXME: Duplication */
if (netplay->catch_up)
{
netplay->catch_up = false;
input_driver_unset_nonblock_state();
driver_set_nonblock_state();
}
return;
}
/* Reset if it was requested */
if (netplay->force_reset)
{
core_reset();
netplay->force_reset = false;
}
#ifndef DEBUG_NONDETERMINISTIC_CORES
if (!netplay->force_rewind)
{
/* Skip ahead if we predicted correctly.
* Skip until our simulation failed. */
while (netplay->other_frame_count < netplay->unread_frame_count &&
netplay->other_frame_count < netplay->run_frame_count)
{
struct delta_frame *ptr = &netplay->buffer[netplay->other_ptr];
size_t i;
for (i = 0; i < MAX_USERS; i++)
{
if (memcmp(ptr->simulated_input_state[i], ptr->real_input_state[i],
sizeof(ptr->real_input_state[i])) != 0
&& !ptr->used_real[i])
break;
}
if (i != MAX_USERS) break;
netplay_handle_frame_hash(netplay, ptr);
netplay->other_ptr = NEXT_PTR(netplay->other_ptr);
netplay->other_frame_count++;
}
}
#endif
/* Now replay the real input if we've gotten ahead of it */
if (netplay->force_rewind ||
(netplay->other_frame_count < netplay->unread_frame_count &&
netplay->other_frame_count < netplay->run_frame_count))
{
retro_ctx_serialize_info_t serial_info;
/* Replay frames. */
netplay->is_replay = true;
netplay->replay_ptr = netplay->other_ptr;
netplay->replay_frame_count = netplay->other_frame_count;
if (netplay->quirks & NETPLAY_QUIRK_INITIALIZATION)
/* Make sure we're initialized before we start loading things */
netplay_wait_and_init_serialization(netplay);
serial_info.data = NULL;
serial_info.data_const = netplay->buffer[netplay->replay_ptr].state;
serial_info.size = netplay->state_size;
if (!core_unserialize(&serial_info))
{
RARCH_ERR("Netplay savestate loading failed: Prepare for desync!\n");
}
while (netplay->replay_frame_count < netplay->run_frame_count)
{
retro_time_t start, tm;
struct delta_frame *ptr = &netplay->buffer[netplay->replay_ptr];
serial_info.data = ptr->state;
serial_info.size = netplay->state_size;
serial_info.data_const = NULL;
start = cpu_features_get_time_usec();
/* Remember the current state */
memset(serial_info.data, 0, serial_info.size);
core_serialize(&serial_info);
if (netplay->replay_frame_count < netplay->unread_frame_count)
netplay_handle_frame_hash(netplay, ptr);
/* Re-simulate this frame's input */
netplay_simulate_input(netplay, netplay->replay_ptr, true);
autosave_lock();
core_run();
autosave_unlock();
netplay->replay_ptr = NEXT_PTR(netplay->replay_ptr);
netplay->replay_frame_count++;
#ifdef DEBUG_NONDETERMINISTIC_CORES
if (ptr->have_remote && netplay_delta_frame_ready(netplay, &netplay->buffer[netplay->replay_ptr], netplay->replay_frame_count))
{
RARCH_LOG("PRE %u: %X\n", netplay->replay_frame_count-1, netplay_delta_frame_crc(netplay, ptr));
if (netplay->is_server)
RARCH_LOG("INP %X %X\n", ptr->real_input_state[0], ptr->self_state[0]);
else
RARCH_LOG("INP %X %X\n", ptr->self_state[0], ptr->real_input_state[0]);
ptr = &netplay->buffer[netplay->replay_ptr];
serial_info.data = ptr->state;
memset(serial_info.data, 0, serial_info.size);
core_serialize(&serial_info);
RARCH_LOG("POST %u: %X\n", netplay->replay_frame_count-1, netplay_delta_frame_crc(netplay, ptr));
}
#endif
/* Get our time window */
tm = cpu_features_get_time_usec() - start;
netplay->frame_run_time_sum -= netplay->frame_run_time[netplay->frame_run_time_ptr];
netplay->frame_run_time[netplay->frame_run_time_ptr] = tm;
netplay->frame_run_time_sum += tm;
netplay->frame_run_time_ptr++;
if (netplay->frame_run_time_ptr >= NETPLAY_FRAME_RUN_TIME_WINDOW)
netplay->frame_run_time_ptr = 0;
}
/* Average our time */
netplay->frame_run_time_avg = netplay->frame_run_time_sum / NETPLAY_FRAME_RUN_TIME_WINDOW;
if (netplay->unread_frame_count < netplay->run_frame_count)
{
netplay->other_ptr = netplay->unread_ptr;
netplay->other_frame_count = netplay->unread_frame_count;
}
else
{
netplay->other_ptr = netplay->run_ptr;
netplay->other_frame_count = netplay->run_frame_count;
}
netplay->is_replay = false;
netplay->force_rewind = false;
}
if (netplay->is_server)
{
uint32_t player;
lo_frame_count = hi_frame_count = netplay->unread_frame_count;
/* Look for players that are ahead of us */
for (player = 0; player < MAX_USERS; player++)
{
if (!(netplay->connected_players & (1<<player))) continue;
if (netplay->read_frame_count[player] > hi_frame_count)
hi_frame_count = netplay->read_frame_count[player];
}
}
else
{
lo_frame_count = hi_frame_count = netplay->server_frame_count;
}
/* If we're behind, try to catch up */
if (netplay->catch_up)
{
/* Are we caught up? */
if (netplay->self_frame_count + 1 >= lo_frame_count)
{
netplay->catch_up = false;
input_driver_unset_nonblock_state();
driver_set_nonblock_state();
}
}
else if (!stalled)
{
if (netplay->self_frame_count + 3 < lo_frame_count)
{
retro_time_t cur_time = cpu_features_get_time_usec();
uint32_t cur_behind = lo_frame_count - netplay->self_frame_count;
/* We're behind, but we'll only try to catch up if we're actually
* falling behind, i.e. if we're more behind after some time */
if (netplay->catch_up_time == 0)
{
/* Record our current time to check for catch-up later */
netplay->catch_up_time = cur_time;
netplay->catch_up_behind = cur_behind;
}
else if (cur_time - netplay->catch_up_time > CATCH_UP_CHECK_TIME_USEC)
{
/* Time to check how far behind we are */
if (netplay->catch_up_behind <= cur_behind)
{
/* We're definitely falling behind! */
netplay->catch_up = true;
netplay->catch_up_time = 0;
input_driver_set_nonblock_state();
driver_set_nonblock_state();
}
else
{
/* Check again in another period */
netplay->catch_up_time = cur_time;
netplay->catch_up_behind = cur_behind;
}
}
}
else if (netplay->self_frame_count + 3 < hi_frame_count)
{
size_t i;
netplay->catch_up_time = 0;
/* We're falling behind some clients but not others, so request that
* clients ahead of us stall */
for (i = 0; i < netplay->connections_size; i++)
{
struct netplay_connection *connection = &netplay->connections[i];
int player;
if (!connection->active ||
connection->mode != NETPLAY_CONNECTION_PLAYING)
continue;
player = connection->player;
/* Are they ahead? */
if (netplay->self_frame_count + 3 < netplay->read_frame_count[player])
{
/* Tell them to stall */
if (connection->stall_frame + NETPLAY_MAX_REQ_STALL_FREQUENCY <
netplay->self_frame_count)
{
connection->stall_frame = netplay->self_frame_count;
netplay_cmd_stall(netplay, connection,
netplay->read_frame_count[player] -
netplay->self_frame_count + 1);
}
}
}
}
else
netplay->catch_up_time = 0;
}
else
netplay->catch_up_time = 0;
}
