diff options
| -rw-r--r-- | Alc/alc.cpp | 97 | ||||
| -rw-r--r-- | Alc/alcontext.h | 9 |
2 files changed, 60 insertions, 46 deletions
diff --git a/Alc/alc.cpp b/Alc/alc.cpp index 4527ce85..fa909091 100644 --- a/Alc/alc.cpp +++ b/Alc/alc.cpp @@ -2727,29 +2727,28 @@ static void ReleaseThreadCtx(ALCcontext *context) /* VerifyContext * - * Checks that the given context is valid, and increments its reference count. + * Checks if the given context is valid, returning a new reference to it if so. */ -static ALCboolean VerifyContext(ALCcontext **context) +static ContextRef VerifyContext(ALCcontext *context) { std::lock_guard<std::recursive_mutex> _{ListLock}; ALCdevice *dev{DeviceList.load()}; while(dev) { - ALCcontext *ctx = ATOMIC_LOAD(&dev->ContextList, almemory_order_acquire); + ALCcontext *ctx = dev->ContextList.load(std::memory_order_acquire); while(ctx) { - if(ctx == *context) + if(ctx == context) { ALCcontext_IncRef(ctx); - return ALC_TRUE; + return ContextRef{ctx}; } - ctx = ATOMIC_LOAD(&ctx->next, almemory_order_relaxed); + ctx = ctx->next.load(std::memory_order_relaxed); } - dev = ATOMIC_LOAD(&dev->next, almemory_order_relaxed); + dev = dev->next.load(std::memory_order_relaxed); } - *context = nullptr; - return ALC_FALSE; + return ContextRef{}; } @@ -2893,13 +2892,11 @@ ALC_API ALCvoid ALC_APIENTRY alcSuspendContext(ALCcontext *context) if(!SuspendDefers) return; - if(!VerifyContext(&context)) + ContextRef ctx{VerifyContext(context)}; + if(!ctx) alcSetError(nullptr, ALC_INVALID_CONTEXT); else - { - ALCcontext_DeferUpdates(context); - ALCcontext_DecRef(context); - } + ALCcontext_DeferUpdates(ctx.get()); } /* alcProcessContext @@ -2911,13 +2908,11 @@ ALC_API ALCvoid ALC_APIENTRY alcProcessContext(ALCcontext *context) if(!SuspendDefers) return; - if(!VerifyContext(&context)) + ContextRef ctx{VerifyContext(context)}; + if(!ctx) alcSetError(nullptr, ALC_INVALID_CONTEXT); else - { - ALCcontext_ProcessUpdates(context); - ALCcontext_DecRef(context); - } + ALCcontext_ProcessUpdates(ctx.get()); } @@ -3712,26 +3707,25 @@ ALC_API ALCcontext* ALC_APIENTRY alcCreateContext(ALCdevice *device, const ALCin ALC_API ALCvoid ALC_APIENTRY alcDestroyContext(ALCcontext *context) { std::unique_lock<std::recursive_mutex> listlock{ListLock}; - if(!VerifyContext(&context)) + ContextRef ctx{VerifyContext(context)}; + if(!ctx) { listlock.unlock(); alcSetError(nullptr, ALC_INVALID_CONTEXT); return; } - ALCdevice* Device{context->Device}; + ALCdevice* Device{ctx->Device}; if(Device) { std::lock_guard<almtx_t> _{Device->BackendLock}; - if(!ReleaseContext(context, Device)) + if(!ReleaseContext(ctx.get(), Device)) { V0(Device->Backend,stop)(); Device->Flags &= ~DEVICE_RUNNING; } } listlock.unlock(); - - ALCcontext_DecRef(context); } @@ -3764,20 +3758,29 @@ ALC_API ALCcontext* ALC_APIENTRY alcGetThreadContext(void) ALC_API ALCboolean ALC_APIENTRY alcMakeContextCurrent(ALCcontext *context) { /* context must be valid or nullptr */ - if(context && !VerifyContext(&context)) + ContextRef ctx; + if(context) { - alcSetError(nullptr, ALC_INVALID_CONTEXT); - return ALC_FALSE; + ctx = VerifyContext(context); + if(!ctx) + { + alcSetError(nullptr, ALC_INVALID_CONTEXT); + return ALC_FALSE; + } } - /* context's reference count is already incremented */ - context = GlobalContext.exchange(context); - if(context) ALCcontext_DecRef(context); + /* Release this reference (if any) to store it in the GlobalContext + * pointer. Take ownership of the reference (if any) that was previously + * stored there. + */ + ctx = ContextRef{GlobalContext.exchange(ctx.release())}; - if((context=LocalContext.get()) != nullptr) - { - LocalContext.set(nullptr); - ALCcontext_DecRef(context); - } + /* Reset (decrement) the previous global reference by replacing it with the + * thread-local context. Take ownership of the thread-local context + * reference (if any), clearing the storage to null. + */ + ctx = ContextRef{LocalContext.get()}; + if(ctx) LocalContext.set(nullptr); + /* Reset (decrement) the previous thread-local reference. */ return ALC_TRUE; } @@ -3789,15 +3792,19 @@ ALC_API ALCboolean ALC_APIENTRY alcMakeContextCurrent(ALCcontext *context) ALC_API ALCboolean ALC_APIENTRY alcSetThreadContext(ALCcontext *context) { /* context must be valid or nullptr */ - if(context && !VerifyContext(&context)) + ContextRef ctx; + if(context) { - alcSetError(nullptr, ALC_INVALID_CONTEXT); - return ALC_FALSE; + ctx = VerifyContext(context); + if(!ctx) + { + alcSetError(nullptr, ALC_INVALID_CONTEXT); + return ALC_FALSE; + } } /* context's reference count is already incremented */ - ALCcontext *old{LocalContext.get()}; - LocalContext.set(context); - if(old) ALCcontext_DecRef(old); + ContextRef old{LocalContext.get()}; + LocalContext.set(ctx.release()); return ALC_TRUE; } @@ -3809,15 +3816,13 @@ ALC_API ALCboolean ALC_APIENTRY alcSetThreadContext(ALCcontext *context) */ ALC_API ALCdevice* ALC_APIENTRY alcGetContextsDevice(ALCcontext *Context) { - if(!VerifyContext(&Context)) + ContextRef ctx{VerifyContext(Context)}; + if(!ctx) { alcSetError(nullptr, ALC_INVALID_CONTEXT); return nullptr; } - ALCdevice *Device{Context->Device}; - ALCcontext_DecRef(Context); - - return Device; + return ctx->Device; } diff --git a/Alc/alcontext.h b/Alc/alcontext.h index 1d66ffc6..26616f18 100644 --- a/Alc/alcontext.h +++ b/Alc/alcontext.h @@ -157,6 +157,8 @@ class ContextRef { public: ContextRef() noexcept = default; + ContextRef(ContextRef&& rhs) noexcept : mCtx{rhs.mCtx} + { rhs.mCtx = nullptr; } explicit ContextRef(ALCcontext *ctx) noexcept : mCtx(ctx) { } ~ContextRef() { reset(); } @@ -173,6 +175,13 @@ public: ALCcontext* operator->() noexcept { return mCtx; } ALCcontext* get() noexcept { return mCtx; } + + ALCcontext* release() noexcept + { + ALCcontext *ret{mCtx}; + mCtx = nullptr; + return ret; + } }; |