al/event.cpp

   1
   2 #include "config.h"
   3
   4 #include "event.h"
   5
   6 #include <array>
   7 #include <atomic>
   8 #include <bitset>
   9 #include <exception>
  10 #include <memory>
  11 #include <mutex>
  12 #include <new>
  13 #include <optional>
  14 #include <string>
  15 #include <string_view>
  16 #include <thread>
  17 #include <tuple>
  18 #include <utility>
  19 #include <variant>
  20
  21 #include "AL/al.h"
  22 #include "AL/alc.h"
  23 #include "AL/alext.h"
  24
  25 #include "alc/context.h"
  26 #include "alc/inprogext.h"
  27 #include "alsem.h"
  28 #include "alspan.h"
  29 #include "core/async_event.h"
  30 #include "core/context.h"
  31 #include "core/effects/base.h"
  32 #include "core/logging.h"
  33 #include "debug.h"
  34 #include "direct_defs.h"
  35 #include "intrusive_ptr.h"
  36 #include "opthelpers.h"
  37 #include "ringbuffer.h"
  38
  39
  40 namespace {
  41
  42 template<typename... Ts>
  43 struct overloaded : Ts... { using Ts::operator()...; };
  44
  45 template<typename... Ts>
  46 overloaded(Ts...) -> overloaded<Ts...>;
  47
  48 int EventThread(ALCcontext *context)
  49 {
  50     RingBuffer *ring{context->mAsyncEvents.get()};
  51     bool quitnow{false};
  52     while(!quitnow)
  53     {
  54         auto evt_data = ring->getReadVector().first;
  55         if(evt_data.len == 0)
  56         {
  57             context->mEventSem.wait();
  58             continue;
  59         }
  60
  61         std::lock_guard<std::mutex> eventlock{context->mEventCbLock};
  62         auto evt_span = al::span{std::launder(reinterpret_cast<AsyncEvent*>(evt_data.buf)),
  63             evt_data.len};
  64         for(auto &event : evt_span)
  65         {
  66             quitnow = std::holds_alternative<AsyncKillThread>(event);
  67             if(quitnow) UNLIKELY break;
  68
  69             auto enabledevts = context->mEnabledEvts.load(std::memory_order_acquire);
  70             auto proc_killthread = [](AsyncKillThread&) { };
  71             auto proc_release = [](AsyncEffectReleaseEvent &evt)
  72             {
  73                 al::intrusive_ptr<EffectState>{evt.mEffectState};
  74             };
  75             auto proc_srcstate = [context,enabledevts](AsyncSourceStateEvent &evt)
  76             {
  77                 if(!context->mEventCb
  78                     || !enabledevts.test(al::to_underlying(AsyncEnableBits::SourceState)))
  79                     return;
  80
  81                 ALuint state{};
  82                 std::string msg{"Source ID " + std::to_string(evt.mId)};
  83                 msg += " state has changed to ";
  84                 switch(evt.mState)
  85                 {
  86                 case AsyncSrcState::Reset:
  87                     msg += "AL_INITIAL";
  88                     state = AL_INITIAL;
  89                     break;
  90                 case AsyncSrcState::Stop:
  91                     msg += "AL_STOPPED";
  92                     state = AL_STOPPED;
  93                     break;
  94                 case AsyncSrcState::Play:
  95                     msg += "AL_PLAYING";
  96                     state = AL_PLAYING;
  97                     break;
  98                 case AsyncSrcState::Pause:
  99                     msg += "AL_PAUSED";
 100                     state = AL_PAUSED;
 101                     break;
 102                 }
 103                 context->mEventCb(AL_EVENT_TYPE_SOURCE_STATE_CHANGED_SOFT, evt.mId, state,
 104                     static_cast<ALsizei>(msg.length()), msg.c_str(), context->mEventParam);
 105             };
 106             auto proc_buffercomp = [context,enabledevts](AsyncBufferCompleteEvent &evt)
 107             {
 108                 if(!context->mEventCb
 109                     || !enabledevts.test(al::to_underlying(AsyncEnableBits::BufferCompleted)))
 110                     return;
 111
 112                 std::string msg{std::to_string(evt.mCount)};
 113                 if(evt.mCount == 1) msg += " buffer completed";
 114                 else msg += " buffers completed";
 115                 context->mEventCb(AL_EVENT_TYPE_BUFFER_COMPLETED_SOFT, evt.mId, evt.mCount,
 116                     static_cast<ALsizei>(msg.length()), msg.c_str(), context->mEventParam);
 117             };
 118             auto proc_disconnect = [context,enabledevts](AsyncDisconnectEvent &evt)
 119             {
 120                 const std::string_view message{evt.msg.data()};
 121
 122                 context->debugMessage(DebugSource::System, DebugType::Error, 0,
 123                     DebugSeverity::High, message);
 124
 125                 if(context->mEventCb
 126                     && enabledevts.test(al::to_underlying(AsyncEnableBits::Disconnected)))
 127                     context->mEventCb(AL_EVENT_TYPE_DISCONNECTED_SOFT, 0, 0,
 128                         static_cast<ALsizei>(message.length()), message.data(),
 129                         context->mEventParam);
 130             };
 131
 132             std::visit(overloaded{proc_srcstate, proc_buffercomp, proc_release, proc_disconnect,
 133                 proc_killthread}, event);
 134         }
 135         std::destroy(evt_span.begin(), evt_span.end());
 136         ring->readAdvance(evt_span.size());
 137     }
 138     return 0;
 139 }
 140
 141 constexpr std::optional<AsyncEnableBits> GetEventType(ALenum etype) noexcept
 142 {
 143     switch(etype)
 144     {
 145     case AL_EVENT_TYPE_BUFFER_COMPLETED_SOFT: return AsyncEnableBits::BufferCompleted;
 146     case AL_EVENT_TYPE_DISCONNECTED_SOFT: return AsyncEnableBits::Disconnected;
 147     case AL_EVENT_TYPE_SOURCE_STATE_CHANGED_SOFT: return AsyncEnableBits::SourceState;
 148     }
 149     return std::nullopt;
 150 }
 151
 152 } // namespace
 153
 154
 155 void StartEventThrd(ALCcontext *ctx)
 156 {
 157     try {
 158         ctx->mEventThread = std::thread{EventThread, ctx};
 159     }
 160     catch(std::exception& e) {
 161         ERR("Failed to start event thread: %s\n", e.what());
 162     }
 163     catch(...) {
 164         ERR("Failed to start event thread! Expect problems.\n");
 165     }
 166 }
 167
 168 void StopEventThrd(ALCcontext *ctx)
 169 {
 170     RingBuffer *ring{ctx->mAsyncEvents.get()};
 171     auto evt_data = ring->getWriteVector().first;
 172     if(evt_data.len == 0)
 173     {
 174         do {
 175             std::this_thread::yield();
 176             evt_data = ring->getWriteVector().first;
 177         } while(evt_data.len == 0);
 178     }
 179     std::ignore = InitAsyncEvent<AsyncKillThread>(evt_data.buf);
 180     ring->writeAdvance(1);
 181
 182     ctx->mEventSem.post();
 183     if(ctx->mEventThread.joinable())
 184         ctx->mEventThread.join();
 185 }
 186
 187 AL_API DECL_FUNCEXT3(void, alEventControl,SOFT, ALsizei,count, const ALenum*,types, ALboolean,enable)
 188 FORCE_ALIGN void AL_APIENTRY alEventControlDirectSOFT(ALCcontext *context, ALsizei count,
 189     const ALenum *types, ALboolean enable) noexcept
 190 {
 191     if(count < 0) context->setError(AL_INVALID_VALUE, "Controlling %d events", count);
 192     if(count <= 0) return;
 193     if(!types) return context->setError(AL_INVALID_VALUE, "NULL pointer");
 194
 195     ContextBase::AsyncEventBitset flags{};
 196     for(ALenum evttype : al::span{types, static_cast<uint>(count)})
 197     {
 198         auto etype = GetEventType(evttype);
 199         if(!etype)
 200             return context->setError(AL_INVALID_ENUM, "Invalid event type 0x%04x", evttype);
 201         flags.set(al::to_underlying(*etype));
 202     }
 203
 204     if(enable)
 205     {
 206         auto enabledevts = context->mEnabledEvts.load(std::memory_order_relaxed);
 207         while(context->mEnabledEvts.compare_exchange_weak(enabledevts, enabledevts|flags,
 208             std::memory_order_acq_rel, std::memory_order_acquire) == 0)
 209         {
 210             /* enabledevts is (re-)filled with the current value on failure, so
 211              * just try again.
 212              */
 213         }
 214     }
 215     else
 216     {
 217         auto enabledevts = context->mEnabledEvts.load(std::memory_order_relaxed);
 218         while(context->mEnabledEvts.compare_exchange_weak(enabledevts, enabledevts&~flags,
 219             std::memory_order_acq_rel, std::memory_order_acquire) == 0)
 220         {
 221         }
 222         /* Wait to ensure the event handler sees the changed flags before
 223          * returning.
 224          */
 225         std::lock_guard<std::mutex> eventlock{context->mEventCbLock};
 226     }
 227 }
 228
 229 AL_API DECL_FUNCEXT2(void, alEventCallback,SOFT, ALEVENTPROCSOFT,callback, void*,userParam)
 230 FORCE_ALIGN void AL_APIENTRY alEventCallbackDirectSOFT(ALCcontext *context,
 231     ALEVENTPROCSOFT callback, void *userParam) noexcept
 232 {
 233     std::lock_guard<std::mutex> eventlock{context->mEventCbLock};
 234     context->mEventCb = callback;
 235     context->mEventParam = userParam;
 236 }