SCI32: Make sure audio is not paused from the future

This can occur when a save game from the past is loaded and the
audio system was paused prior to loading the save game. This was
fixed eventually in SSCI somewhere around GK2, since it pauses
all audio before restoring a game and then resumes it after the
save game is loaded (after all of the audio channels have been
added from the save game). Since this would seem to be a problem
for earlier games as well, this change is applied universally
instead of being conditionally applied only to the games with
interpreters containing this change.

This patch contains some additional sanity checks that emit
warnings if individual channels end up being started from the
future. There was never such checking in SSCI, and it does not
seem likely to ever happen, but it is unclear right now if this is
an actual problem or not.

1 files changed, 19 insertions, 2 deletions

diff --git a/engines/sci/sound/audio32.cpp b/engines/sci/sound/audio32.cpp
index be3f99dcea..7622305adb 100644
--- a/engines/sci/sound/audio32.cpp
+++ b/engines/sci/sound/audio32.cpp
@@ -842,6 +842,9 @@ uint16 Audio32::play(int16 channelIndex, const ResourceId resourceId, const bool
 	channel.startedAtTick = now;
 
 	if (_numActiveChannels == 1) {
+		if (_pausedAtTick) {
+			_pausedAtTick = now;
+		}
 		_startedAtTick = now;
 	}
 
@@ -868,18 +871,29 @@ bool Audio32::resume(const int16 channelIndex) {
 			AudioChannel &channel = getChannel(i);
 			if (!channel.pausedAtTick) {
 				channel.startedAtTick += now - _pausedAtTick;
+				if (channel.startedAtTick > now) {
+					warning("%s is being resumed in the future", channel.id.toString().c_str());
+				}
 			}
 		}
 
 		_startedAtTick += now - _pausedAtTick;
+		if (_startedAtTick > now) {
+			warning("Audio32 is being resumed in the future");
+		}
 		_pausedAtTick = 0;
 		return true;
 	} else if (channelIndex == kRobotChannel) {
 		for (int i = 0; i < _numActiveChannels; ++i) {
 			AudioChannel &channel = getChannel(i);
 			if (channel.robot) {
-				channel.startedAtTick += now - channel.pausedAtTick;
-				channel.pausedAtTick = 0;
+				if (channel.pausedAtTick) {
+					channel.startedAtTick += now - channel.pausedAtTick;
+					if (channel.startedAtTick > now) {
+						warning("Robot audio is being resumed in the future");
+					}
+					channel.pausedAtTick = 0;
+				}
 				return true;
 			}
 		}
@@ -887,6 +901,9 @@ bool Audio32::resume(const int16 channelIndex) {
 		AudioChannel &channel = getChannel(channelIndex);
 		if (channel.pausedAtTick) {
 			channel.startedAtTick += now - channel.pausedAtTick;
+			if (channel.startedAtTick > now) {
+				warning("%s is being resumed in the future", channel.id.toString().c_str());
+			}
 			channel.pausedAtTick = 0;
 			return true;
 		}