(svn r10462) -Add: a command dumper/loader that could be enabled compile-time and server side only to aid debugging some desyncs, i.e. dump the stream of commands so it could be replayed in exactly the same way later. This should primarily be used to make desyncs more easily reproducable, so it can be properly debugged.

1 files changed, 52 insertions, 0 deletions

diff --git a/src/network/network.cpp b/src/network/network.cpp
index 52f6ddbb0..5b7ab937c 100644
--- a/src/network/network.cpp
+++ b/src/network/network.cpp
@@ -37,6 +37,7 @@
 #include "../console.h" /* IConsoleCmdExec */
 #include <stdarg.h> /* va_list */
 #include "../md5.h"
+#include "../fileio.h"
 
 /* Check whether NETWORK_NUM_LANDSCAPES is still in sync with NUM_LANDSCAPE */
 assert_compile((int)NETWORK_NUM_LANDSCAPES == (int)NUM_LANDSCAPE);
@@ -195,6 +196,9 @@ void CDECL NetworkTextMessage(NetworkAction action, uint16 color, bool self_send
 			break;
 	}
 
+#ifdef DEBUG_DUMP_COMMANDS
+	debug_dump_commands("ddc:cmsg:%d;%d;%s\n", _date, _date_fract, message);
+#endif /* DUMP_COMMANDS */
 	IConsolePrintF(color, "%s", message);
 	AddTextMessage(color, duration, "%s", message);
 }
@@ -1235,6 +1239,9 @@ static bool NetworkDoClientLoop()
 			if (_sync_seed_1 != _random_seeds[0][0]) {
 #endif
 				NetworkError(STR_NETWORK_ERR_DESYNC);
+#ifdef DEBUG_DUMP_COMMANDS
+				debug_dump_commands("ddc:serr:%d;%d\n", _date, _date_fract);
+#endif /* DUMP_COMMANDS */
 				DEBUG(net, 0, "Sync error detected!");
 				NetworkClientError(NETWORK_RECV_STATUS_DESYNC, DEREF_CLIENT(0));
 				return false;
@@ -1280,6 +1287,37 @@ void NetworkGameLoop()
 	if (!NetworkReceive()) return;
 
 	if (_network_server) {
+#ifdef DEBUG_DUMP_COMMANDS
+		static FILE *f = FioFOpenFile("commands.log", "rb", SAVE_DIR);
+		static Date next_date = 0;
+		static uint32 next_date_fract;
+		static CommandPacket *cp = NULL;
+		if (f == NULL && next_date == 0) {
+			printf("Cannot open commands.log\n");
+			next_date = 1;
+		}
+
+		while (f != NULL && !feof(f)) {
+			if (cp != NULL && _date == next_date && _date_fract == next_date_fract) {
+				_current_player = cp->player;
+				_cmd_text = cp->text;
+				DoCommandP(cp->tile, cp->p1, cp->p2, NULL, cp->cmd);
+				free(cp);
+				cp = NULL;
+			}
+
+			if (cp != NULL) break;
+
+			char buff[4096];
+			if (fgets(buff, lengthof(buff), f) == NULL) break;
+			if (strncmp(buff, "ddc:cmd:", 8) != 0) continue;
+			cp = MallocT<CommandPacket>(1);
+			int player;
+			sscanf(&buff[8], "%d;%d;%d;%d;%d;%d;%d;%s", &next_date, &next_date_fract, &player, &cp->tile, &cp->p1, &cp->p2, &cp->cmd, cp->text);
+			cp->player = (Owner)player;
+		}
+#endif /* DUMP_COMMANDS */
+
 		bool send_frame = false;
 
 		// We first increase the _frame_counter
@@ -1436,4 +1474,18 @@ bool IsNetworkCompatibleVersion(const char *other)
 			strncmp(_openttd_revision, other, NETWORK_REVISION_LENGTH - 1) == 0;
 }
 
+#ifdef DEBUG_DUMP_COMMANDS
+void CDECL debug_dump_commands(const char *s, ...)
+{
+	static FILE *f = FioFOpenFile("commands-out.log", "wb", SAVE_DIR);
+	if (f == NULL) return;
+
+	va_list va;
+	va_start(va, s);
+	vfprintf(f, s, va);
+	va_end(va);
+
+	fflush(f);
+}
+#endif /* DEBUG_DUMP_COMMANDS */
 #endif /* ENABLE_NETWORK */