Fix a bug with ma_resource_manager_data_stream relating to seeking.

research/miniaudio_engine.h

@@ -7268,6 +7268,16 @@ MA_API ma_result ma_resource_manager_data_stream_map(ma_resource_manager_data_st
     return MA_SUCCESS;
 }
 
+static void ma_resource_manager_data_stream_set_absolute_cursor(ma_resource_manager_data_stream* pDataStream, ma_uint64 absoluteCursor)
+{
+    /* Loop if possible. */
+    if (absoluteCursor > pDataStream->totalLengthInPCMFrames && pDataStream->totalLengthInPCMFrames > 0) {
+        absoluteCursor = absoluteCursor % pDataStream->totalLengthInPCMFrames;
+    }
+
+    c89atomic_exchange_64(&pDataStream->absoluteCursor, absoluteCursor);
+}
+
 MA_API ma_result ma_resource_manager_data_stream_unmap(ma_resource_manager_data_stream* pDataStream, ma_uint64 frameCount)
 {
     ma_uint32 newRelativeCursor;
@@ -7292,11 +7302,8 @@ MA_API ma_result ma_resource_manager_data_stream_unmap(ma_resource_manager_data_
 
     pageSizeInFrames = ma_resource_manager_data_stream_get_page_size_in_frames(pDataStream);
 
-    /* The absolute cursor needs to be updated. We want to make sure to loop if possible. */
-    pDataStream->absoluteCursor += frameCount;
-    if (pDataStream->absoluteCursor > pDataStream->totalLengthInPCMFrames && pDataStream->totalLengthInPCMFrames > 0) {
-        pDataStream->absoluteCursor = pDataStream->absoluteCursor % pDataStream->totalLengthInPCMFrames;
-    }
+    /* The absolute cursor needs to be updated for ma_resource_manager_data_stream_get_cursor_in_pcm_frames(). */
+    ma_resource_manager_data_stream_set_absolute_cursor(pDataStream, c89atomic_load_64(&pDataStream->absoluteCursor) + frameCount);
 
     /* Here is where we need to check if we need to load a new page, and if so, post a job to load it. */
     newRelativeCursor = pDataStream->relativeCursor + (ma_uint32)frameCount;
@@ -7346,6 +7353,9 @@ MA_API ma_result ma_resource_manager_data_stream_seek_to_pcm_frame(ma_resource_m
     /* Increment the seek counter first to indicate to read_paged_pcm_frames() and map_paged_pcm_frames() that we are in the middle of a seek and MA_BUSY should be returned. */
     c89atomic_fetch_add_32(&pDataStream->seekCounter, 1);
 
+    /* Update the absolute cursor so that ma_resource_manager_data_stream_get_cursor_in_pcm_frames() returns the new position. */
+    ma_resource_manager_data_stream_set_absolute_cursor(pDataStream, frameIndex);
+
     /*
     We need to clear our currently loaded pages so that the stream starts playback from the new seek point as soon as possible. These are for the purpose of the public
     API and will be ignored by the seek job. The seek job will operate on the assumption that both pages have been marked as invalid and the cursor is at the start of