Partially implement an extension to hold sources on disconnect

Rather than stopping voices/sources when the device becomes disconnected, the
context can be set to leave them alone. As a consequence, their state will
remain as playing and they'll keep their last known sample offset indefinately.
For applications mindful of this behavior, it will allow resetting or reopening
the device to reconnect and automatically resume where it left off.

1 files changed, 5 insertions, 0 deletions

diff --git a/alc/alc.cpp b/alc/alc.cpp
index d06ca067..47b77758 100644
--- a/alc/alc.cpp
+++ b/alc/alc.cpp
@@ -834,6 +834,8 @@ constexpr struct {
     DECL(AL_FORMAT_UHJ4CHN8_SOFT),
     DECL(AL_FORMAT_UHJ4CHN16_SOFT),
     DECL(AL_FORMAT_UHJ4CHN_FLOAT32_SOFT),
+
+    DECL(AL_STOP_SOURCES_ON_DISCONNECT_SOFT),
 };
 #undef DECL
 
@@ -889,6 +891,7 @@ constexpr ALchar alExtList[] =
     "AL_SOFT_events "
     "AL_SOFTX_filter_gain_ex "
     "AL_SOFT_gain_clamp_ex "
+    "AL_SOFTX_hold_on_disconnect "
     "AL_SOFT_loop_points "
     "AL_SOFTX_map_buffer "
     "AL_SOFT_MSADPCM "
@@ -2269,6 +2272,8 @@ static bool ResetDeviceParams(ALCdevice *device, const int *attrList)
         for(ContextBase *ctxbase : *device->mContexts.load(std::memory_order_acquire))
         {
             auto *ctx = static_cast<ALCcontext*>(ctxbase);
+            if(!ctx->mStopVoicesOnDisconnect.load(std::memory_order_acquire))
+                continue;
 
             /* Clear any pending voice changes and reallocate voices to get a
              * clean restart.