Integrated SDL2 and switch to a test rom, fixed some issues in recompilation

test/portultra/events.cpp

@@ -3,8 +3,10 @@
 #include <chrono>
 #include <cinttypes>
 #include <variant>
+#include <unordered_map>
 
 #include <Windows.h>
+#include "SDL.h"
 #include "blockingconcurrentqueue.h"
 
 #include "ultra64.h"
@@ -85,7 +87,7 @@ extern "C" void osViSetEvent(RDRAM_ARG PTR(OSMesgQueue) mq_, OSMesg msg, u32 ret
     events_context.vi.retrace_count = retrace_count;
 }
 
-constexpr uint32_t speed_multiplier = 10;
+constexpr uint32_t speed_multiplier = 1;
 
 // N64 CPU counter ticks per millisecond
 constexpr uint32_t counter_per_ms = 46'875 * speed_multiplier;
@@ -176,11 +178,57 @@ void dp_complete() {
 void RT64Init(uint8_t* rom, uint8_t* rdram);
 void RT64SendDL(uint8_t* rdram, const OSTask* task);
 void RT64UpdateScreen(uint32_t vi_origin);
-void RT64PumpEvents();
+
+std::unordered_map<SDL_Scancode, int> button_map{
+    { SDL_Scancode::SDL_SCANCODE_LEFT,  0x0002 },
+    { SDL_Scancode::SDL_SCANCODE_RIGHT, 0x0001 },
+    { SDL_Scancode::SDL_SCANCODE_UP,    0x0008 },
+    { SDL_Scancode::SDL_SCANCODE_DOWN,  0x0004 }
+};
+
+extern int button;
+extern int stick_x;
+extern int stick_y;
+
+int sdl_event_filter(void* userdata, SDL_Event* event) {
+    switch (event->type) {
+    case SDL_EventType::SDL_KEYUP:
+    case SDL_EventType::SDL_KEYDOWN:
+        {
+            const Uint8* key_states = SDL_GetKeyboardState(nullptr);
+            int new_button = 0;
+
+            for (const auto& mapping : button_map) {
+                if (key_states[mapping.first]) {
+                    new_button |= mapping.second;
+                }
+            }
+
+            button = new_button;
+
+            stick_x = 127 * (key_states[SDL_Scancode::SDL_SCANCODE_D] - key_states[SDL_Scancode::SDL_SCANCODE_A]);
+            stick_y = 127 * (key_states[SDL_Scancode::SDL_SCANCODE_W] - key_states[SDL_Scancode::SDL_SCANCODE_S]);
+        }
+        break;
+    case SDL_EventType::SDL_QUIT:
+        std::quick_exit(ERROR_SUCCESS);
+        break;
+    }
+    return 1;
+}
 
 void gfx_thread_func(uint8_t* rdram, uint8_t* rom) {
     using namespace std::chrono_literals;
+    if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_JOYSTICK) < 0) {
+        fprintf(stderr, "Failed to initialize SDL2: %s\n", SDL_GetError());
+        std::quick_exit(EXIT_FAILURE);
+    }
     RT64Init(rom, rdram);
+    SDL_Window* window = SDL_GetWindowFromID(1);
+    // TODO set this window title in RT64, create the window here and send it to RT64, or something else entirely
+    // as the current window name visibly changes as RT64 is initialized
+    SDL_SetWindowTitle(window, "Recomp");
+    SDL_SetEventFilter(sdl_event_filter, nullptr);
 
     while (true) {
         // Try to pull an action from the queue
@@ -205,7 +253,7 @@ void gfx_thread_func(uint8_t* rdram, uint8_t* rom) {
         }
 
         // Handle events
-        RT64PumpEvents();
+        SDL_PumpEvents();
     }
 }
 

test/src/cont.cpp

@@ -16,15 +16,27 @@ struct OSContPad {
     u8 errno_;
 };
 
+int button = 0;
+int stick_x = 0;
+int stick_y = 0;
+
+void press_button(int button) {
+
+}
+
+void release_button(int button) {
+
+}
+
 extern "C" void osContGetReadData_recomp(uint8_t* restrict rdram, recomp_context* restrict ctx) {
     int32_t pad = (uint32_t)ctx->r4;
 
     // button
-    MEM_H(0, pad) = 0;
+    MEM_H(0, pad) = button;
     // stick_x
-    MEM_B(2, pad) = 0;
+    MEM_B(2, pad) = stick_x;
     // stick_y
-    MEM_B(3, pad) = 0;
+    MEM_B(3, pad) = stick_y;
     // errno
     MEM_B(4, pad) = 0;
 }

test/src/misc_ultra.cpp

@@ -41,3 +41,7 @@ extern "C" void __osDisableInt_recomp(uint8_t* restrict rdram, recomp_context* r
 extern "C" void __osRestoreInt_recomp(uint8_t* restrict rdram, recomp_context* restrict ctx) {
     ;
 }
+
+extern "C" void __osSetFpcCsr_recomp(uint8_t * restrict rdram, recomp_context * restrict ctx) {
+    ctx->r2 = 0;
+}

test/src/pi.cpp

@@ -16,7 +16,7 @@ extern "C" void osCreatePiManager_recomp(uint8_t* restrict rdram, recomp_context
 
 constexpr uint32_t rom_base = 0xB0000000;
 
-void do_rom_read(uint8_t* rdram, int32_t ram_address, uint32_t dev_address, size_t num_bytes) {
+void do_rom_read(uint8_t* rdram, gpr ram_address, uint32_t dev_address, size_t num_bytes) {
     // TODO use word copies when possible
     uint8_t* rom_addr = rom.get() + (dev_address | rom_base) - rom_base;
     for (size_t i = 0; i < num_bytes; i++) {
@@ -30,10 +30,9 @@ extern "C" void osPiStartDma_recomp(uint8_t* restrict rdram, recomp_context* res
     uint32_t pri = ctx->r5;
     uint32_t direction = ctx->r6;
     uint32_t devAddr = ctx->r7;
-    int32_t dramAddr = MEM_W(0x10, ctx->r29);
+    gpr dramAddr = MEM_W(0x10, ctx->r29);
     uint32_t size = MEM_W(0x14, ctx->r29);
-    uint32_t mq_ = MEM_W(0x18, ctx->r29);
-    OSMesgQueue* mq = TO_PTR(OSMesgQueue, mq_);
+    PTR(OSMesgQueue) mq = MEM_W(0x18, ctx->r29);
 
     debug_printf("[pi] DMA from 0x%08X into 0x%08X of size 0x%08X\n", devAddr, dramAddr, size);
 
@@ -44,11 +43,43 @@ extern "C" void osPiStartDma_recomp(uint8_t* restrict rdram, recomp_context* res
     //memcpy(rdram + (dramAddr & 0x3FFFFFF), rom.get() + (devAddr | rom_base) - rom_base, num_bytes);
 
     // Send a message to the mq to indicate that the transfer completed
-    osSendMesg(rdram, mq_, 0, OS_MESG_NOBLOCK);
+    osSendMesg(rdram, mq, 0, OS_MESG_NOBLOCK);
 }
 
+struct OSIoMesgHdr {
+    // These 3 reversed due to endianness
+    u8 status;                 /* Return status */
+    u8 pri;                    /* Message priority (High or Normal) */
+    u16 type;                  /* Message type */
+    PTR(OSMesgQueue) retQueue; /* Return message queue to notify I/O completion */
+};
+
+struct OSIoMesg {
+    OSIoMesgHdr	hdr;    /* Message header */
+    PTR(void) dramAddr;	/* RDRAM buffer address (DMA) */
+    u32 devAddr;	    /* Device buffer address (DMA) */
+    u32 size;		    /* DMA transfer size in bytes */
+    u32 piHandle;	    /* PI device handle */
+};
+
 extern "C" void osEPiStartDma_recomp(uint8_t* restrict rdram, recomp_context* restrict ctx) {
-    ;
+    OSIoMesg* mb = TO_PTR(OSIoMesg, ctx->r5);
+    uint32_t direction = ctx->r6;
+    uint32_t devAddr = mb->devAddr;
+    gpr dramAddr = mb->dramAddr;
+    uint32_t size = mb->size;
+    PTR(OSMesgQueue) mq = mb->hdr.retQueue;
+
+    debug_printf("[pi] DMA from 0x%08X into 0x%08X of size 0x%08X\n", devAddr, dramAddr, size);
+
+    // TODO asynchronous transfer (will require preemption in the scheduler)
+    // TODO this won't handle unaligned DMA
+    do_rom_read(rdram, dramAddr, devAddr, size);
+
+    //memcpy(rdram + (dramAddr & 0x3FFFFFF), rom.get() + (devAddr | rom_base) - rom_base, num_bytes);
+
+    // Send a message to the mq to indicate that the transfer completed
+    osSendMesg(rdram, mq, 0, OS_MESG_NOBLOCK);
 }
 
 extern "C" void osPiGetStatus_recomp(uint8_t * restrict rdram, recomp_context * restrict ctx) {

test/src/portultra_translation.cpp

@@ -5,6 +5,10 @@ extern "C" void osInitialize_recomp(uint8_t * restrict rdram, recomp_context * r
     osInitialize();
 }
 
+extern "C" void __osInitialize_common_recomp(uint8_t * restrict rdram, recomp_context * restrict ctx) {
+    osInitialize();
+}
+
 extern "C" void osCreateThread_recomp(uint8_t* restrict rdram, recomp_context* restrict ctx) {
     osCreateThread(rdram, (uint32_t)ctx->r4, (OSId)ctx->r5, (uint32_t)ctx->r6, (uint32_t)ctx->r7,
         (uint32_t)MEM_W(0x10, ctx->r29), (OSPri)MEM_W(0x14, ctx->r29));

test/src/recomp.cpp

@@ -61,8 +61,12 @@ void run_thread_function(uint8_t* rdram, uint64_t addr, uint64_t sp, uint64_t ar
     func(rdram, &ctx);
 }
 
-extern "C" void game_init(uint8_t* restrict rdram, recomp_context* restrict ctx);
-void do_rom_read(uint8_t* rdram, int32_t ram_address, uint32_t dev_address, size_t num_bytes);
+extern "C" void init(uint8_t * restrict rdram, recomp_context * restrict ctx);
+
+// rocket robot
+//extern "C" void game_init(uint8_t* restrict rdram, recomp_context* restrict ctx);
+// test rom
+void do_rom_read(uint8_t* rdram, gpr ram_address, uint32_t dev_address, size_t num_bytes);
 
 std::unique_ptr<uint8_t[]> rom;
 size_t rom_size;
@@ -105,7 +109,7 @@ int main(int argc, char **argv) {
 
     // Get entrypoint from ROM
     // TODO fix this for other IPL3 versions
-    int32_t entrypoint = byteswap(*reinterpret_cast<uint32_t*>(rom.get() + 0x8));
+    gpr entrypoint = (int32_t)byteswap(*reinterpret_cast<uint32_t*>(rom.get() + 0x8));
 
     // Allocate rdram_buffer
     std::unique_ptr<uint8_t[]> rdram_buffer = std::make_unique<uint8_t[]>(8 * 1024 * 1024);
@@ -153,13 +157,19 @@ int main(int argc, char **argv) {
 
     // Clear bss
     // TODO run the entrypoint instead
-    memset(rdram_buffer.get() + 0XAF860, 0, 0xC00A0u - 0XAF860);
+    // rocket robot
+    //memset(rdram_buffer.get() + 0xAF860, 0, 0xC00A0u - 0XAF860);
+    // test rom
+    memset(rdram_buffer.get() + 0x18670, 0, 0x20D120);
 
     debug_printf("[Recomp] Starting\n");
 
     Multilibultra::preinit(rdram_buffer.get(), rom.get());
 
-    game_init(rdram_buffer.get(), &context);
+    // rocket robot
+    // game_init(rdram_buffer.get(), &context);
+    // test rom
+    init(rdram_buffer.get(), &context);
 
     debug_printf("[Recomp] Quitting\n");
 

test/thirdparty/blockingconcurrentqueue.h

@@ -0,0 +1,582 @@
+// Provides an efficient blocking version of moodycamel::ConcurrentQueue.
+// ©2015-2020 Cameron Desrochers. Distributed under the terms of the simplified
+// BSD license, available at the top of concurrentqueue.h.
+// Also dual-licensed under the Boost Software License (see LICENSE.md)
+// Uses Jeff Preshing's semaphore implementation (under the terms of its
+// separate zlib license, see lightweightsemaphore.h).
+
+#pragma once
+
+#include "concurrentqueue.h"
+#include "lightweightsemaphore.h"
+
+#include <type_traits>
+#include <cerrno>
+#include <memory>
+#include <chrono>
+#include <ctime>
+
+namespace moodycamel
+{
+// This is a blocking version of the queue. It has an almost identical interface to
+// the normal non-blocking version, with the addition of various wait_dequeue() methods
+// and the removal of producer-specific dequeue methods.
+template<typename T, typename Traits = ConcurrentQueueDefaultTraits>
+class BlockingConcurrentQueue
+{
+private:
+	typedef ::moodycamel::ConcurrentQueue<T, Traits> ConcurrentQueue;
+	typedef ::moodycamel::LightweightSemaphore LightweightSemaphore;
+
+public:
+	typedef typename ConcurrentQueue::producer_token_t producer_token_t;
+	typedef typename ConcurrentQueue::consumer_token_t consumer_token_t;
+	
+	typedef typename ConcurrentQueue::index_t index_t;
+	typedef typename ConcurrentQueue::size_t size_t;
+	typedef typename std::make_signed<size_t>::type ssize_t;
+	
+	static const size_t BLOCK_SIZE = ConcurrentQueue::BLOCK_SIZE;
+	static const size_t EXPLICIT_BLOCK_EMPTY_COUNTER_THRESHOLD = ConcurrentQueue::EXPLICIT_BLOCK_EMPTY_COUNTER_THRESHOLD;
+	static const size_t EXPLICIT_INITIAL_INDEX_SIZE = ConcurrentQueue::EXPLICIT_INITIAL_INDEX_SIZE;
+	static const size_t IMPLICIT_INITIAL_INDEX_SIZE = ConcurrentQueue::IMPLICIT_INITIAL_INDEX_SIZE;
+	static const size_t INITIAL_IMPLICIT_PRODUCER_HASH_SIZE = ConcurrentQueue::INITIAL_IMPLICIT_PRODUCER_HASH_SIZE;
+	static const std::uint32_t EXPLICIT_CONSUMER_CONSUMPTION_QUOTA_BEFORE_ROTATE = ConcurrentQueue::EXPLICIT_CONSUMER_CONSUMPTION_QUOTA_BEFORE_ROTATE;
+	static const size_t MAX_SUBQUEUE_SIZE = ConcurrentQueue::MAX_SUBQUEUE_SIZE;
+	
+public:
+	// Creates a queue with at least `capacity` element slots; note that the
+	// actual number of elements that can be inserted without additional memory
+	// allocation depends on the number of producers and the block size (e.g. if
+	// the block size is equal to `capacity`, only a single block will be allocated
+	// up-front, which means only a single producer will be able to enqueue elements
+	// without an extra allocation -- blocks aren't shared between producers).
+	// This method is not thread safe -- it is up to the user to ensure that the
+	// queue is fully constructed before it starts being used by other threads (this
+	// includes making the memory effects of construction visible, possibly with a
+	// memory barrier).
+	explicit BlockingConcurrentQueue(size_t capacity = 6 * BLOCK_SIZE)
+		: inner(capacity), sema(create<LightweightSemaphore, ssize_t, int>(0, (int)Traits::MAX_SEMA_SPINS), &BlockingConcurrentQueue::template destroy<LightweightSemaphore>)
+	{
+		assert(reinterpret_cast<ConcurrentQueue*>((BlockingConcurrentQueue*)1) == &((BlockingConcurrentQueue*)1)->inner && "BlockingConcurrentQueue must have ConcurrentQueue as its first member");
+		if (!sema) {
+			MOODYCAMEL_THROW(std::bad_alloc());
+		}
+	}
+	
+	BlockingConcurrentQueue(size_t minCapacity, size_t maxExplicitProducers, size_t maxImplicitProducers)
+		: inner(minCapacity, maxExplicitProducers, maxImplicitProducers), sema(create<LightweightSemaphore, ssize_t, int>(0, (int)Traits::MAX_SEMA_SPINS), &BlockingConcurrentQueue::template destroy<LightweightSemaphore>)
+	{
+		assert(reinterpret_cast<ConcurrentQueue*>((BlockingConcurrentQueue*)1) == &((BlockingConcurrentQueue*)1)->inner && "BlockingConcurrentQueue must have ConcurrentQueue as its first member");
+		if (!sema) {
+			MOODYCAMEL_THROW(std::bad_alloc());
+		}
+	}
+	
+	// Disable copying and copy assignment
+	BlockingConcurrentQueue(BlockingConcurrentQueue const&) MOODYCAMEL_DELETE_FUNCTION;
+	BlockingConcurrentQueue& operator=(BlockingConcurrentQueue const&) MOODYCAMEL_DELETE_FUNCTION;
+	
+	// Moving is supported, but note that it is *not* a thread-safe operation.
+	// Nobody can use the queue while it's being moved, and the memory effects
+	// of that move must be propagated to other threads before they can use it.
+	// Note: When a queue is moved, its tokens are still valid but can only be
+	// used with the destination queue (i.e. semantically they are moved along
+	// with the queue itself).
+	BlockingConcurrentQueue(BlockingConcurrentQueue&& other) MOODYCAMEL_NOEXCEPT
+		: inner(std::move(other.inner)), sema(std::move(other.sema))
+	{ }
+	
+	inline BlockingConcurrentQueue& operator=(BlockingConcurrentQueue&& other) MOODYCAMEL_NOEXCEPT
+	{
+		return swap_internal(other);
+	}
+	
+	// Swaps this queue's state with the other's. Not thread-safe.
+	// Swapping two queues does not invalidate their tokens, however
+	// the tokens that were created for one queue must be used with
+	// only the swapped queue (i.e. the tokens are tied to the
+	// queue's movable state, not the object itself).
+	inline void swap(BlockingConcurrentQueue& other) MOODYCAMEL_NOEXCEPT
+	{
+		swap_internal(other);
+	}
+	
+private:
+	BlockingConcurrentQueue& swap_internal(BlockingConcurrentQueue& other)
+	{
+		if (this == &other) {
+			return *this;
+		}
+		
+		inner.swap(other.inner);
+		sema.swap(other.sema);
+		return *this;
+	}
+	
+public:
+	// Enqueues a single item (by copying it).
+	// Allocates memory if required. Only fails if memory allocation fails (or implicit
+	// production is disabled because Traits::INITIAL_IMPLICIT_PRODUCER_HASH_SIZE is 0,
+	// or Traits::MAX_SUBQUEUE_SIZE has been defined and would be surpassed).
+	// Thread-safe.
+	inline bool enqueue(T const& item)
+	{
+		if ((details::likely)(inner.enqueue(item))) {
+			sema->signal();
+			return true;
+		}
+		return false;
+	}
+	
+	// Enqueues a single item (by moving it, if possible).
+	// Allocates memory if required. Only fails if memory allocation fails (or implicit
+	// production is disabled because Traits::INITIAL_IMPLICIT_PRODUCER_HASH_SIZE is 0,
+	// or Traits::MAX_SUBQUEUE_SIZE has been defined and would be surpassed).
+	// Thread-safe.
+	inline bool enqueue(T&& item)
+	{
+		if ((details::likely)(inner.enqueue(std::move(item)))) {
+			sema->signal();
+			return true;
+		}
+		return false;
+	}
+	
+	// Enqueues a single item (by copying it) using an explicit producer token.
+	// Allocates memory if required. Only fails if memory allocation fails (or
+	// Traits::MAX_SUBQUEUE_SIZE has been defined and would be surpassed).
+	// Thread-safe.
+	inline bool enqueue(producer_token_t const& token, T const& item)
+	{
+		if ((details::likely)(inner.enqueue(token, item))) {
+			sema->signal();
+			return true;
+		}
+		return false;
+	}
+	
+	// Enqueues a single item (by moving it, if possible) using an explicit producer token.
+	// Allocates memory if required. Only fails if memory allocation fails (or
+	// Traits::MAX_SUBQUEUE_SIZE has been defined and would be surpassed).
+	// Thread-safe.
+	inline bool enqueue(producer_token_t const& token, T&& item)
+	{
+		if ((details::likely)(inner.enqueue(token, std::move(item)))) {
+			sema->signal();
+			return true;
+		}
+		return false;
+	}
+	
+	// Enqueues several items.
+	// Allocates memory if required. Only fails if memory allocation fails (or
+	// implicit production is disabled because Traits::INITIAL_IMPLICIT_PRODUCER_HASH_SIZE
+	// is 0, or Traits::MAX_SUBQUEUE_SIZE has been defined and would be surpassed).
+	// Note: Use std::make_move_iterator if the elements should be moved instead of copied.
+	// Thread-safe.
+	template<typename It>
+	inline bool enqueue_bulk(It itemFirst, size_t count)
+	{
+		if ((details::likely)(inner.enqueue_bulk(std::forward<It>(itemFirst), count))) {
+			sema->signal((LightweightSemaphore::ssize_t)(ssize_t)count);
+			return true;
+		}
+		return false;
+	}
+	
+	// Enqueues several items using an explicit producer token.
+	// Allocates memory if required. Only fails if memory allocation fails
+	// (or Traits::MAX_SUBQUEUE_SIZE has been defined and would be surpassed).
+	// Note: Use std::make_move_iterator if the elements should be moved
+	// instead of copied.
+	// Thread-safe.
+	template<typename It>
+	inline bool enqueue_bulk(producer_token_t const& token, It itemFirst, size_t count)
+	{
+		if ((details::likely)(inner.enqueue_bulk(token, std::forward<It>(itemFirst), count))) {
+			sema->signal((LightweightSemaphore::ssize_t)(ssize_t)count);
+			return true;
+		}
+		return false;
+	}
+	
+	// Enqueues a single item (by copying it).
+	// Does not allocate memory. Fails if not enough room to enqueue (or implicit
+	// production is disabled because Traits::INITIAL_IMPLICIT_PRODUCER_HASH_SIZE
+	// is 0).
+	// Thread-safe.
+	inline bool try_enqueue(T const& item)
+	{
+		if (inner.try_enqueue(item)) {
+			sema->signal();
+			return true;
+		}
+		return false;
+	}
+	
+	// Enqueues a single item (by moving it, if possible).
+	// Does not allocate memory (except for one-time implicit producer).
+	// Fails if not enough room to enqueue (or implicit production is
+	// disabled because Traits::INITIAL_IMPLICIT_PRODUCER_HASH_SIZE is 0).
+	// Thread-safe.
+	inline bool try_enqueue(T&& item)
+	{
+		if (inner.try_enqueue(std::move(item))) {
+			sema->signal();
+			return true;
+		}
+		return false;
+	}
+	
+	// Enqueues a single item (by copying it) using an explicit producer token.
+	// Does not allocate memory. Fails if not enough room to enqueue.
+	// Thread-safe.
+	inline bool try_enqueue(producer_token_t const& token, T const& item)
+	{
+		if (inner.try_enqueue(token, item)) {
+			sema->signal();
+			return true;
+		}
+		return false;
+	}
+	
+	// Enqueues a single item (by moving it, if possible) using an explicit producer token.
+	// Does not allocate memory. Fails if not enough room to enqueue.
+	// Thread-safe.
+	inline bool try_enqueue(producer_token_t const& token, T&& item)
+	{
+		if (inner.try_enqueue(token, std::move(item))) {
+			sema->signal();
+			return true;
+		}
+		return false;
+	}
+	
+	// Enqueues several items.
+	// Does not allocate memory (except for one-time implicit producer).
+	// Fails if not enough room to enqueue (or implicit production is
+	// disabled because Traits::INITIAL_IMPLICIT_PRODUCER_HASH_SIZE is 0).
+	// Note: Use std::make_move_iterator if the elements should be moved
+	// instead of copied.
+	// Thread-safe.
+	template<typename It>
+	inline bool try_enqueue_bulk(It itemFirst, size_t count)
+	{
+		if (inner.try_enqueue_bulk(std::forward<It>(itemFirst), count)) {
+			sema->signal((LightweightSemaphore::ssize_t)(ssize_t)count);
+			return true;
+		}
+		return false;
+	}
+	
+	// Enqueues several items using an explicit producer token.
+	// Does not allocate memory. Fails if not enough room to enqueue.
+	// Note: Use std::make_move_iterator if the elements should be moved
+	// instead of copied.
+	// Thread-safe.
+	template<typename It>
+	inline bool try_enqueue_bulk(producer_token_t const& token, It itemFirst, size_t count)
+	{
+		if (inner.try_enqueue_bulk(token, std::forward<It>(itemFirst), count)) {
+			sema->signal((LightweightSemaphore::ssize_t)(ssize_t)count);
+			return true;
+		}
+		return false;
+	}
+	
+	
+	// Attempts to dequeue from the queue.
+	// Returns false if all producer streams appeared empty at the time they
+	// were checked (so, the queue is likely but not guaranteed to be empty).
+	// Never allocates. Thread-safe.
+	template<typename U>
+	inline bool try_dequeue(U& item)
+	{
+		if (sema->tryWait()) {
+			while (!inner.try_dequeue(item)) {
+				continue;
+			}
+			return true;
+		}
+		return false;
+	}
+	
+	// Attempts to dequeue from the queue using an explicit consumer token.
+	// Returns false if all producer streams appeared empty at the time they
+	// were checked (so, the queue is likely but not guaranteed to be empty).
+	// Never allocates. Thread-safe.
+	template<typename U>
+	inline bool try_dequeue(consumer_token_t& token, U& item)
+	{
+		if (sema->tryWait()) {
+			while (!inner.try_dequeue(token, item)) {
+				continue;
+			}
+			return true;
+		}
+		return false;
+	}
+	
+	// Attempts to dequeue several elements from the queue.
+	// Returns the number of items actually dequeued.
+	// Returns 0 if all producer streams appeared empty at the time they
+	// were checked (so, the queue is likely but not guaranteed to be empty).
+	// Never allocates. Thread-safe.
+	template<typename It>
+	inline size_t try_dequeue_bulk(It itemFirst, size_t max)
+	{
+		size_t count = 0;
+		max = (size_t)sema->tryWaitMany((LightweightSemaphore::ssize_t)(ssize_t)max);
+		while (count != max) {
+			count += inner.template try_dequeue_bulk<It&>(itemFirst, max - count);
+		}
+		return count;
+	}
+	
+	// Attempts to dequeue several elements from the queue using an explicit consumer token.
+	// Returns the number of items actually dequeued.
+	// Returns 0 if all producer streams appeared empty at the time they
+	// were checked (so, the queue is likely but not guaranteed to be empty).
+	// Never allocates. Thread-safe.
+	template<typename It>
+	inline size_t try_dequeue_bulk(consumer_token_t& token, It itemFirst, size_t max)
+	{
+		size_t count = 0;
+		max = (size_t)sema->tryWaitMany((LightweightSemaphore::ssize_t)(ssize_t)max);
+		while (count != max) {
+			count += inner.template try_dequeue_bulk<It&>(token, itemFirst, max - count);
+		}
+		return count;
+	}
+	
+	
+	
+	// Blocks the current thread until there's something to dequeue, then
+	// dequeues it.
+	// Never allocates. Thread-safe.
+	template<typename U>
+	inline void wait_dequeue(U& item)
+	{
+		while (!sema->wait()) {
+			continue;
+		}
+		while (!inner.try_dequeue(item)) {
+			continue;
+		}
+	}
+
+	// Blocks the current thread until either there's something to dequeue
+	// or the timeout (specified in microseconds) expires. Returns false
+	// without setting `item` if the timeout expires, otherwise assigns
+	// to `item` and returns true.
+	// Using a negative timeout indicates an indefinite timeout,
+	// and is thus functionally equivalent to calling wait_dequeue.
+	// Never allocates. Thread-safe.
+	template<typename U>
+	inline bool wait_dequeue_timed(U& item, std::int64_t timeout_usecs)
+	{
+		if (!sema->wait(timeout_usecs)) {
+			return false;
+		}
+		while (!inner.try_dequeue(item)) {
+			continue;
+		}
+		return true;
+	}
+    
+    // Blocks the current thread until either there's something to dequeue
+	// or the timeout expires. Returns false without setting `item` if the
+    // timeout expires, otherwise assigns to `item` and returns true.
+	// Never allocates. Thread-safe.
+	template<typename U, typename Rep, typename Period>
+	inline bool wait_dequeue_timed(U& item, std::chrono::duration<Rep, Period> const& timeout)
+    {
+        return wait_dequeue_timed(item, std::chrono::duration_cast<std::chrono::microseconds>(timeout).count());
+    }
+	
+	// Blocks the current thread until there's something to dequeue, then
+	// dequeues it using an explicit consumer token.
+	// Never allocates. Thread-safe.
+	template<typename U>
+	inline void wait_dequeue(consumer_token_t& token, U& item)
+	{
+		while (!sema->wait()) {
+			continue;
+		}
+		while (!inner.try_dequeue(token, item)) {
+			continue;
+		}
+	}
+	
+	// Blocks the current thread until either there's something to dequeue
+	// or the timeout (specified in microseconds) expires. Returns false
+	// without setting `item` if the timeout expires, otherwise assigns
+	// to `item` and returns true.
+	// Using a negative timeout indicates an indefinite timeout,
+	// and is thus functionally equivalent to calling wait_dequeue.
+	// Never allocates. Thread-safe.
+	template<typename U>
+	inline bool wait_dequeue_timed(consumer_token_t& token, U& item, std::int64_t timeout_usecs)
+	{
+		if (!sema->wait(timeout_usecs)) {
+			return false;
+		}
+		while (!inner.try_dequeue(token, item)) {
+			continue;
+		}
+		return true;
+	}
+    
+    // Blocks the current thread until either there's something to dequeue
+	// or the timeout expires. Returns false without setting `item` if the
+    // timeout expires, otherwise assigns to `item` and returns true.
+	// Never allocates. Thread-safe.
+	template<typename U, typename Rep, typename Period>
+	inline bool wait_dequeue_timed(consumer_token_t& token, U& item, std::chrono::duration<Rep, Period> const& timeout)
+    {
+        return wait_dequeue_timed(token, item, std::chrono::duration_cast<std::chrono::microseconds>(timeout).count());
+    }
+	
+	// Attempts to dequeue several elements from the queue.
+	// Returns the number of items actually dequeued, which will
+	// always be at least one (this method blocks until the queue
+	// is non-empty) and at most max.
+	// Never allocates. Thread-safe.
+	template<typename It>
+	inline size_t wait_dequeue_bulk(It itemFirst, size_t max)
+	{
+		size_t count = 0;
+		max = (size_t)sema->waitMany((LightweightSemaphore::ssize_t)(ssize_t)max);
+		while (count != max) {
+			count += inner.template try_dequeue_bulk<It&>(itemFirst, max - count);
+		}
+		return count;
+	}
+	
+	// Attempts to dequeue several elements from the queue.
+	// Returns the number of items actually dequeued, which can
+	// be 0 if the timeout expires while waiting for elements,
+	// and at most max.
+	// Using a negative timeout indicates an indefinite timeout,
+	// and is thus functionally equivalent to calling wait_dequeue_bulk.
+	// Never allocates. Thread-safe.
+	template<typename It>
+	inline size_t wait_dequeue_bulk_timed(It itemFirst, size_t max, std::int64_t timeout_usecs)
+	{
+		size_t count = 0;
+		max = (size_t)sema->waitMany((LightweightSemaphore::ssize_t)(ssize_t)max, timeout_usecs);
+		while (count != max) {
+			count += inner.template try_dequeue_bulk<It&>(itemFirst, max - count);
+		}
+		return count;
+	}
+    
+    // Attempts to dequeue several elements from the queue.
+	// Returns the number of items actually dequeued, which can
+	// be 0 if the timeout expires while waiting for elements,
+	// and at most max.
+	// Never allocates. Thread-safe.
+	template<typename It, typename Rep, typename Period>
+	inline size_t wait_dequeue_bulk_timed(It itemFirst, size_t max, std::chrono::duration<Rep, Period> const& timeout)
+    {
+        return wait_dequeue_bulk_timed<It&>(itemFirst, max, std::chrono::duration_cast<std::chrono::microseconds>(timeout).count());
+    }
+	
+	// Attempts to dequeue several elements from the queue using an explicit consumer token.
+	// Returns the number of items actually dequeued, which will
+	// always be at least one (this method blocks until the queue
+	// is non-empty) and at most max.
+	// Never allocates. Thread-safe.
+	template<typename It>
+	inline size_t wait_dequeue_bulk(consumer_token_t& token, It itemFirst, size_t max)
+	{
+		size_t count = 0;
+		max = (size_t)sema->waitMany((LightweightSemaphore::ssize_t)(ssize_t)max);
+		while (count != max) {
+			count += inner.template try_dequeue_bulk<It&>(token, itemFirst, max - count);
+		}
+		return count;
+	}
+	
+	// Attempts to dequeue several elements from the queue using an explicit consumer token.
+	// Returns the number of items actually dequeued, which can
+	// be 0 if the timeout expires while waiting for elements,
+	// and at most max.
+	// Using a negative timeout indicates an indefinite timeout,
+	// and is thus functionally equivalent to calling wait_dequeue_bulk.
+	// Never allocates. Thread-safe.
+	template<typename It>
+	inline size_t wait_dequeue_bulk_timed(consumer_token_t& token, It itemFirst, size_t max, std::int64_t timeout_usecs)
+	{
+		size_t count = 0;
+		max = (size_t)sema->waitMany((LightweightSemaphore::ssize_t)(ssize_t)max, timeout_usecs);
+		while (count != max) {
+			count += inner.template try_dequeue_bulk<It&>(token, itemFirst, max - count);
+		}
+		return count;
+	}
+	
+	// Attempts to dequeue several elements from the queue using an explicit consumer token.
+	// Returns the number of items actually dequeued, which can
+	// be 0 if the timeout expires while waiting for elements,
+	// and at most max.
+	// Never allocates. Thread-safe.
+	template<typename It, typename Rep, typename Period>
+	inline size_t wait_dequeue_bulk_timed(consumer_token_t& token, It itemFirst, size_t max, std::chrono::duration<Rep, Period> const& timeout)
+    {
+        return wait_dequeue_bulk_timed<It&>(token, itemFirst, max, std::chrono::duration_cast<std::chrono::microseconds>(timeout).count());
+    }
+	
+	
+	// Returns an estimate of the total number of elements currently in the queue. This
+	// estimate is only accurate if the queue has completely stabilized before it is called
+	// (i.e. all enqueue and dequeue operations have completed and their memory effects are
+	// visible on the calling thread, and no further operations start while this method is
+	// being called).
+	// Thread-safe.
+	inline size_t size_approx() const
+	{
+		return (size_t)sema->availableApprox();
+	}
+	
+	
+	// Returns true if the underlying atomic variables used by
+	// the queue are lock-free (they should be on most platforms).
+	// Thread-safe.
+	static constexpr bool is_lock_free()
+	{
+		return ConcurrentQueue::is_lock_free();
+	}
+	
+
+private:
+	template<typename U, typename A1, typename A2>
+	static inline U* create(A1&& a1, A2&& a2)
+	{
+		void* p = (Traits::malloc)(sizeof(U));
+		return p != nullptr ? new (p) U(std::forward<A1>(a1), std::forward<A2>(a2)) : nullptr;
+	}
+	
+	template<typename U>
+	static inline void destroy(U* p)
+	{
+		if (p != nullptr) {
+			p->~U();
+		}
+		(Traits::free)(p);
+	}
+	
+private:
+	ConcurrentQueue inner;
+	std::unique_ptr<LightweightSemaphore, void (*)(LightweightSemaphore*)> sema;
+};
+
+
+template<typename T, typename Traits>
+inline void swap(BlockingConcurrentQueue<T, Traits>& a, BlockingConcurrentQueue<T, Traits>& b) MOODYCAMEL_NOEXCEPT
+{
+	a.swap(b);
+}
+
+}	// end namespace moodycamel

test/thirdparty/lightweightsemaphore.h

@@ -0,0 +1,425 @@
+// Provides an efficient implementation of a semaphore (LightweightSemaphore).
+// This is an extension of Jeff Preshing's sempahore implementation (licensed 
+// under the terms of its separate zlib license) that has been adapted and
+// extended by Cameron Desrochers.
+
+#pragma once
+
+#include <cstddef> // For std::size_t
+#include <atomic>
+#include <type_traits> // For std::make_signed<T>
+
+#if defined(_WIN32)
+// Avoid including windows.h in a header; we only need a handful of
+// items, so we'll redeclare them here (this is relatively safe since
+// the API generally has to remain stable between Windows versions).
+// I know this is an ugly hack but it still beats polluting the global
+// namespace with thousands of generic names or adding a .cpp for nothing.
+extern "C" {
+	struct _SECURITY_ATTRIBUTES;
+	__declspec(dllimport) void* __stdcall CreateSemaphoreW(_SECURITY_ATTRIBUTES* lpSemaphoreAttributes, long lInitialCount, long lMaximumCount, const wchar_t* lpName);
+	__declspec(dllimport) int __stdcall CloseHandle(void* hObject);
+	__declspec(dllimport) unsigned long __stdcall WaitForSingleObject(void* hHandle, unsigned long dwMilliseconds);
+	__declspec(dllimport) int __stdcall ReleaseSemaphore(void* hSemaphore, long lReleaseCount, long* lpPreviousCount);
+}
+#elif defined(__MACH__)
+#include <mach/mach.h>
+#elif defined(__unix__)
+#include <semaphore.h>
+
+#if defined(__GLIBC_PREREQ) && defined(_GNU_SOURCE)
+#if __GLIBC_PREREQ(2,30)
+#define MOODYCAMEL_LIGHTWEIGHTSEMAPHORE_MONOTONIC
+#endif
+#endif
+#endif
+
+namespace moodycamel
+{
+namespace details
+{
+
+// Code in the mpmc_sema namespace below is an adaptation of Jeff Preshing's
+// portable + lightweight semaphore implementations, originally from
+// https://github.com/preshing/cpp11-on-multicore/blob/master/common/sema.h
+// LICENSE:
+// Copyright (c) 2015 Jeff Preshing
+//
+// This software is provided 'as-is', without any express or implied
+// warranty. In no event will the authors be held liable for any damages
+// arising from the use of this software.
+//
+// Permission is granted to anyone to use this software for any purpose,
+// including commercial applications, and to alter it and redistribute it
+// freely, subject to the following restrictions:
+//
+// 1. The origin of this software must not be misrepresented; you must not
+//	claim that you wrote the original software. If you use this software
+//	in a product, an acknowledgement in the product documentation would be
+//	appreciated but is not required.
+// 2. Altered source versions must be plainly marked as such, and must not be
+//	misrepresented as being the original software.
+// 3. This notice may not be removed or altered from any source distribution.
+#if defined(_WIN32)
+class Semaphore
+{
+private:
+	void* m_hSema;
+	
+	Semaphore(const Semaphore& other) MOODYCAMEL_DELETE_FUNCTION;
+	Semaphore& operator=(const Semaphore& other) MOODYCAMEL_DELETE_FUNCTION;
+
+public:
+	Semaphore(int initialCount = 0)
+	{
+		assert(initialCount >= 0);
+		const long maxLong = 0x7fffffff;
+		m_hSema = CreateSemaphoreW(nullptr, initialCount, maxLong, nullptr);
+		assert(m_hSema);
+	}
+
+	~Semaphore()
+	{
+		CloseHandle(m_hSema);
+	}
+
+	bool wait()
+	{
+		const unsigned long infinite = 0xffffffff;
+		return WaitForSingleObject(m_hSema, infinite) == 0;
+	}
+	
+	bool try_wait()
+	{
+		return WaitForSingleObject(m_hSema, 0) == 0;
+	}
+	
+	bool timed_wait(std::uint64_t usecs)
+	{
+		return WaitForSingleObject(m_hSema, (unsigned long)(usecs / 1000)) == 0;
+	}
+
+	void signal(int count = 1)
+	{
+		while (!ReleaseSemaphore(m_hSema, count, nullptr));
+	}
+};
+#elif defined(__MACH__)
+//---------------------------------------------------------
+// Semaphore (Apple iOS and OSX)
+// Can't use POSIX semaphores due to http://lists.apple.com/archives/darwin-kernel/2009/Apr/msg00010.html
+//---------------------------------------------------------
+class Semaphore
+{
+private:
+	semaphore_t m_sema;
+
+	Semaphore(const Semaphore& other) MOODYCAMEL_DELETE_FUNCTION;
+	Semaphore& operator=(const Semaphore& other) MOODYCAMEL_DELETE_FUNCTION;
+
+public:
+	Semaphore(int initialCount = 0)
+	{
+		assert(initialCount >= 0);
+		kern_return_t rc = semaphore_create(mach_task_self(), &m_sema, SYNC_POLICY_FIFO, initialCount);
+		assert(rc == KERN_SUCCESS);
+		(void)rc;
+	}
+
+	~Semaphore()
+	{
+		semaphore_destroy(mach_task_self(), m_sema);
+	}
+
+	bool wait()
+	{
+		return semaphore_wait(m_sema) == KERN_SUCCESS;
+	}
+	
+	bool try_wait()
+	{
+		return timed_wait(0);
+	}
+	
+	bool timed_wait(std::uint64_t timeout_usecs)
+	{
+		mach_timespec_t ts;
+		ts.tv_sec = static_cast<unsigned int>(timeout_usecs / 1000000);
+		ts.tv_nsec = static_cast<int>((timeout_usecs % 1000000) * 1000);
+
+		// added in OSX 10.10: https://developer.apple.com/library/prerelease/mac/documentation/General/Reference/APIDiffsMacOSX10_10SeedDiff/modules/Darwin.html
+		kern_return_t rc = semaphore_timedwait(m_sema, ts);
+		return rc == KERN_SUCCESS;
+	}
+
+	void signal()
+	{
+		while (semaphore_signal(m_sema) != KERN_SUCCESS);
+	}
+
+	void signal(int count)
+	{
+		while (count-- > 0)
+		{
+			while (semaphore_signal(m_sema) != KERN_SUCCESS);
+		}
+	}
+};
+#elif defined(__unix__)
+//---------------------------------------------------------
+// Semaphore (POSIX, Linux)
+//---------------------------------------------------------
+class Semaphore
+{
+private:
+	sem_t m_sema;
+
+	Semaphore(const Semaphore& other) MOODYCAMEL_DELETE_FUNCTION;
+	Semaphore& operator=(const Semaphore& other) MOODYCAMEL_DELETE_FUNCTION;
+
+public:
+	Semaphore(int initialCount = 0)
+	{
+		assert(initialCount >= 0);
+		int rc = sem_init(&m_sema, 0, static_cast<unsigned int>(initialCount));
+		assert(rc == 0);
+		(void)rc;
+	}
+
+	~Semaphore()
+	{
+		sem_destroy(&m_sema);
+	}
+
+	bool wait()
+	{
+		// http://stackoverflow.com/questions/2013181/gdb-causes-sem-wait-to-fail-with-eintr-error
+		int rc;
+		do {
+			rc = sem_wait(&m_sema);
+		} while (rc == -1 && errno == EINTR);
+		return rc == 0;
+	}
+
+	bool try_wait()
+	{
+		int rc;
+		do {
+			rc = sem_trywait(&m_sema);
+		} while (rc == -1 && errno == EINTR);
+		return rc == 0;
+	}
+
+	bool timed_wait(std::uint64_t usecs)
+	{
+		struct timespec ts;
+		const int usecs_in_1_sec = 1000000;
+		const int nsecs_in_1_sec = 1000000000;
+#ifdef MOODYCAMEL_LIGHTWEIGHTSEMAPHORE_MONOTONIC
+		clock_gettime(CLOCK_MONOTONIC, &ts);
+#else
+		clock_gettime(CLOCK_REALTIME, &ts);
+#endif
+		ts.tv_sec += (time_t)(usecs / usecs_in_1_sec);
+		ts.tv_nsec += (long)(usecs % usecs_in_1_sec) * 1000;
+		// sem_timedwait bombs if you have more than 1e9 in tv_nsec
+		// so we have to clean things up before passing it in
+		if (ts.tv_nsec >= nsecs_in_1_sec) {
+			ts.tv_nsec -= nsecs_in_1_sec;
+			++ts.tv_sec;
+		}
+
+		int rc;
+		do {
+#ifdef MOODYCAMEL_LIGHTWEIGHTSEMAPHORE_MONOTONIC
+			rc = sem_clockwait(&m_sema, CLOCK_MONOTONIC, &ts);
+#else
+			rc = sem_timedwait(&m_sema, &ts);
+#endif
+		} while (rc == -1 && errno == EINTR);
+		return rc == 0;
+	}
+
+	void signal()
+	{
+		while (sem_post(&m_sema) == -1);
+	}
+
+	void signal(int count)
+	{
+		while (count-- > 0)
+		{
+			while (sem_post(&m_sema) == -1);
+		}
+	}
+};
+#else
+#error Unsupported platform! (No semaphore wrapper available)
+#endif
+
+}	// end namespace details
+
+
+//---------------------------------------------------------
+// LightweightSemaphore
+//---------------------------------------------------------
+class LightweightSemaphore
+{
+public:
+	typedef std::make_signed<std::size_t>::type ssize_t;
+
+private:
+	std::atomic<ssize_t> m_count;
+	details::Semaphore m_sema;
+	int m_maxSpins;
+
+	bool waitWithPartialSpinning(std::int64_t timeout_usecs = -1)
+	{
+		ssize_t oldCount;
+		int spin = m_maxSpins;
+		while (--spin >= 0)
+		{
+			oldCount = m_count.load(std::memory_order_relaxed);
+			if ((oldCount > 0) && m_count.compare_exchange_strong(oldCount, oldCount - 1, std::memory_order_acquire, std::memory_order_relaxed))
+				return true;
+			std::atomic_signal_fence(std::memory_order_acquire);	 // Prevent the compiler from collapsing the loop.
+		}
+		oldCount = m_count.fetch_sub(1, std::memory_order_acquire);
+		if (oldCount > 0)
+			return true;
+		if (timeout_usecs < 0)
+		{
+			if (m_sema.wait())
+				return true;
+		}
+		if (timeout_usecs > 0 && m_sema.timed_wait((std::uint64_t)timeout_usecs))
+			return true;
+		// At this point, we've timed out waiting for the semaphore, but the
+		// count is still decremented indicating we may still be waiting on
+		// it. So we have to re-adjust the count, but only if the semaphore
+		// wasn't signaled enough times for us too since then. If it was, we
+		// need to release the semaphore too.
+		while (true)
+		{
+			oldCount = m_count.load(std::memory_order_acquire);
+			if (oldCount >= 0 && m_sema.try_wait())
+				return true;
+			if (oldCount < 0 && m_count.compare_exchange_strong(oldCount, oldCount + 1, std::memory_order_relaxed, std::memory_order_relaxed))
+				return false;
+		}
+	}
+
+	ssize_t waitManyWithPartialSpinning(ssize_t max, std::int64_t timeout_usecs = -1)
+	{
+		assert(max > 0);
+		ssize_t oldCount;
+		int spin = m_maxSpins;
+		while (--spin >= 0)
+		{
+			oldCount = m_count.load(std::memory_order_relaxed);
+			if (oldCount > 0)
+			{
+				ssize_t newCount = oldCount > max ? oldCount - max : 0;
+				if (m_count.compare_exchange_strong(oldCount, newCount, std::memory_order_acquire, std::memory_order_relaxed))
+					return oldCount - newCount;
+			}
+			std::atomic_signal_fence(std::memory_order_acquire);
+		}
+		oldCount = m_count.fetch_sub(1, std::memory_order_acquire);
+		if (oldCount <= 0)
+		{
+			if ((timeout_usecs == 0) || (timeout_usecs < 0 && !m_sema.wait()) || (timeout_usecs > 0 && !m_sema.timed_wait((std::uint64_t)timeout_usecs)))
+			{
+				while (true)
+				{
+					oldCount = m_count.load(std::memory_order_acquire);
+					if (oldCount >= 0 && m_sema.try_wait())
+						break;
+					if (oldCount < 0 && m_count.compare_exchange_strong(oldCount, oldCount + 1, std::memory_order_relaxed, std::memory_order_relaxed))
+						return 0;
+				}
+			}
+		}
+		if (max > 1)
+			return 1 + tryWaitMany(max - 1);
+		return 1;
+	}
+
+public:
+	LightweightSemaphore(ssize_t initialCount = 0, int maxSpins = 10000) : m_count(initialCount), m_maxSpins(maxSpins)
+	{
+		assert(initialCount >= 0);
+		assert(maxSpins >= 0);
+	}
+
+	bool tryWait()
+	{
+		ssize_t oldCount = m_count.load(std::memory_order_relaxed);
+		while (oldCount > 0)
+		{
+			if (m_count.compare_exchange_weak(oldCount, oldCount - 1, std::memory_order_acquire, std::memory_order_relaxed))
+				return true;
+		}
+		return false;
+	}
+
+	bool wait()
+	{
+		return tryWait() || waitWithPartialSpinning();
+	}
+
+	bool wait(std::int64_t timeout_usecs)
+	{
+		return tryWait() || waitWithPartialSpinning(timeout_usecs);
+	}
+
+	// Acquires between 0 and (greedily) max, inclusive
+	ssize_t tryWaitMany(ssize_t max)
+	{
+		assert(max >= 0);
+		ssize_t oldCount = m_count.load(std::memory_order_relaxed);
+		while (oldCount > 0)
+		{
+			ssize_t newCount = oldCount > max ? oldCount - max : 0;
+			if (m_count.compare_exchange_weak(oldCount, newCount, std::memory_order_acquire, std::memory_order_relaxed))
+				return oldCount - newCount;
+		}
+		return 0;
+	}
+
+	// Acquires at least one, and (greedily) at most max
+	ssize_t waitMany(ssize_t max, std::int64_t timeout_usecs)
+	{
+		assert(max >= 0);
+		ssize_t result = tryWaitMany(max);
+		if (result == 0 && max > 0)
+			result = waitManyWithPartialSpinning(max, timeout_usecs);
+		return result;
+	}
+	
+	ssize_t waitMany(ssize_t max)
+	{
+		ssize_t result = waitMany(max, -1);
+		assert(result > 0);
+		return result;
+	}
+
+	void signal(ssize_t count = 1)
+	{
+		assert(count >= 0);
+		ssize_t oldCount = m_count.fetch_add(count, std::memory_order_release);
+		ssize_t toRelease = -oldCount < count ? -oldCount : count;
+		if (toRelease > 0)
+		{
+			m_sema.signal((int)toRelease);
+		}
+	}
+	
+	std::size_t availableApprox() const
+	{
+		ssize_t count = m_count.load(std::memory_order_relaxed);
+		return count > 0 ? static_cast<std::size_t>(count) : 0;
+	}
+};
+
+}   // end namespace moodycamel