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 "alsem.h"
  27 #include "alspan.h"
  28 #include "alstring.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 "error.h"
  36 #include "intrusive_ptr.h"
  37 #include "opthelpers.h"
  38 #include "ringbuffer.h"
  39
  40
  41 namespace {
  42
  43 template<typename... Ts>
  44 struct overloaded : Ts... { using Ts::operator()...; };
  45
  46 template<typename... Ts>
  47 overloaded(Ts...) -> overloaded<Ts...>;
  48
  49 int EventThread(ALCcontext *context)
  50 {
  51     RingBuffer *ring{context->mAsyncEvents.get()};
  52     bool quitnow{false};
  53     while(!quitnow)
  54     {
  55         auto evt_data = ring->getReadVector().first;
  56         if(evt_data.len == 0)
  57         {
  58             context->mEventSem.wait();
  59             continue;
  60         }
  61
  62         auto eventlock = std::lock_guard{context->mEventCbLock};
  63         const auto enabledevts = context->mEnabledEvts.load(std::memory_order_acquire);
  64         auto evt_span = al::span{std::launder(reinterpret_cast<AsyncEvent*>(evt_data.buf)),
  65             evt_data.len};
  66         for(auto &event : evt_span)
  67         {
  68             quitnow = std::holds_alternative<AsyncKillThread>(event);
  69             if(quitnow) UNLIKELY break;
  70
  71             auto proc_killthread = [](AsyncKillThread&) { };
  72             auto proc_release = [](AsyncEffectReleaseEvent &evt)
  73             {
  74                 al::intrusive_ptr<EffectState>{evt.mEffectState};
  75             };
  76             auto proc_srcstate = [context,enabledevts](AsyncSourceStateEvent &evt)
  77             {
  78                 if(!context->mEventCb
  79                     || !enabledevts.test(al::to_underlying(AsyncEnableBits::SourceState)))
  80                     return;
  81
  82                 ALuint state{};
  83                 std::string msg{"Source ID " + std::to_string(evt.mId)};
  84                 msg += " state has changed to ";
  85                 switch(evt.mState)
  86                 {
  87                 case AsyncSrcState::Reset:
  88                     msg += "AL_INITIAL";
  89                     state = AL_INITIAL;
  90                     break;
  91                 case AsyncSrcState::Stop:
  92                     msg += "AL_STOPPED";
  93                     state = AL_STOPPED;
  94                     break;
  95                 case AsyncSrcState::Play:
  96                     msg += "AL_PLAYING";
  97                     state = AL_PLAYING;
  98                     break;
  99                 case AsyncSrcState::Pause:
 100                     msg += "AL_PAUSED";
 101                     state = AL_PAUSED;
 102                     break;
 103                 }
 104                 context->mEventCb(AL_EVENT_TYPE_SOURCE_STATE_CHANGED_SOFT, evt.mId, state,
 105                     al::sizei(msg), msg.c_str(), context->mEventParam);
 106             };
 107             auto proc_buffercomp = [context,enabledevts](AsyncBufferCompleteEvent &evt)
 108             {
 109                 if(!context->mEventCb
 110                     || !enabledevts.test(al::to_underlying(AsyncEnableBits::BufferCompleted)))
 111                     return;
 112
 113                 std::string msg{std::to_string(evt.mCount)};
 114                 if(evt.mCount == 1) msg += " buffer completed";
 115                 else msg += " buffers completed";
 116                 context->mEventCb(AL_EVENT_TYPE_BUFFER_COMPLETED_SOFT, evt.mId, evt.mCount,
 117                     al::sizei(msg), msg.c_str(), context->mEventParam);
 118             };
 119             auto proc_disconnect = [context,enabledevts](AsyncDisconnectEvent &evt)
 120             {
 121                 if(!context->mEventCb
 122                     || !enabledevts.test(al::to_underlying(AsyncEnableBits::Disconnected)))
 123                     return;
 124
 125                 context->mEventCb(AL_EVENT_TYPE_DISCONNECTED_SOFT, 0, 0, al::sizei(evt.msg),
 126                     evt.msg.c_str(), context->mEventParam);
 127             };
 128
 129             std::visit(overloaded{proc_srcstate, proc_buffercomp, proc_release, proc_disconnect,
 130                 proc_killthread}, event);
 131         }
 132         std::destroy(evt_span.begin(), evt_span.end());
 133         ring->readAdvance(evt_span.size());
 134     }
 135     return 0;
 136 }
 137
 138 constexpr std::optional<AsyncEnableBits> GetEventType(ALenum etype) noexcept
 139 {
 140     switch(etype)
 141     {
 142     case AL_EVENT_TYPE_BUFFER_COMPLETED_SOFT: return AsyncEnableBits::BufferCompleted;
 143     case AL_EVENT_TYPE_DISCONNECTED_SOFT: return AsyncEnableBits::Disconnected;
 144     case AL_EVENT_TYPE_SOURCE_STATE_CHANGED_SOFT: return AsyncEnableBits::SourceState;
 145     }
 146     return std::nullopt;
 147 }
 148
 149 } // namespace
 150
 151
 152 void StartEventThrd(ALCcontext *ctx)
 153 {
 154     try {
 155         ctx->mEventThread = std::thread{EventThread, ctx};
 156     }
 157     catch(std::exception& e) {
 158         ERR("Failed to start event thread: %s\n", e.what());
 159     }
 160     catch(...) {
 161         ERR("Failed to start event thread! Expect problems.\n");
 162     }
 163 }
 164
 165 void StopEventThrd(ALCcontext *ctx)
 166 {
 167     RingBuffer *ring{ctx->mAsyncEvents.get()};
 168     auto evt_data = ring->getWriteVector().first;
 169     if(evt_data.len == 0)
 170     {
 171         do {
 172             std::this_thread::yield();
 173             evt_data = ring->getWriteVector().first;
 174         } while(evt_data.len == 0);
 175     }
 176     std::ignore = InitAsyncEvent<AsyncKillThread>(evt_data.buf);
 177     ring->writeAdvance(1);
 178
 179     ctx->mEventSem.post();
 180     if(ctx->mEventThread.joinable())
 181         ctx->mEventThread.join();
 182 }
 183
 184 AL_API DECL_FUNCEXT3(void, alEventControl,SOFT, ALsizei,count, const ALenum*,types, ALboolean,enable)
 185 FORCE_ALIGN void AL_APIENTRY alEventControlDirectSOFT(ALCcontext *context, ALsizei count,
 186     const ALenum *types, ALboolean enable) noexcept
 187 try {
 188     if(count < 0)
 189         throw al::context_error{AL_INVALID_VALUE, "Controlling %d events", count};
 190     if(count <= 0) UNLIKELY return;
 191
 192     if(!types)
 193         throw al::context_error{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             throw al::context_error{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 catch(al::context_error& e) {
 229     context->setError(e.errorCode(), "%s", e.what());
 230 }
 231
 232 AL_API DECL_FUNCEXT2(void, alEventCallback,SOFT, ALEVENTPROCSOFT,callback, void*,userParam)
 233 FORCE_ALIGN void AL_APIENTRY alEventCallbackDirectSOFT(ALCcontext *context,
 234     ALEVENTPROCSOFT callback, void *userParam) noexcept
 235 {
 236     std::lock_guard<std::mutex> eventlock{context->mEventCbLock};
 237     context->mEventCb = callback;
 238     context->mEventParam = userParam;
 239 }