winamp/Src/nu/threadpool/ThreadPool.h

99 lines
3.6 KiB
C++

#pragma once
#include <windows.h>
#include <bfc/platform/types.h>
#include <vector>
#include "../autolock.h"
#include "ThreadID.h"
#include "ThreadFunctions.h"
#include "threadpool_types.h"
/* random notes
HANDLEs common to all threads
WaitForMultipleObjectsEx() around these
0 - killswitch
1 - shared APC event. since threads might want to use APCs themselves, we'll use a different mechanism (thread-safe FIFO and an event). the intention is that APCs that can go on any thread will use this handle
2 - per thread APC event.
parameters for "run my function" method
function pointer, user data, flags
flags:
interrupt - for very short non-locking functions where it is safe to interrupt another thread, uses QueueUserAPC
no_wait - spawn a new thread if all threads are busy
com_multithreaded - all threads are created with CoInitialize(0), if you need a COINIT_MULTITHREADED thread, use this flag
parameters for "add my handle" method
handle, function pointer, user data, flags
flags:
single_thread - only one thread in the pool will wait on your object, useful if your handle is not auto-reset
parameters for "function call repeat" - calls your function until you return 0
function pointer, user data, flags
flags:
single_thread - keep calling on the same thread
*/
class ThreadPool : public api_threadpool
{
public:
static const char *getServiceName() { return "Thread Pool API"; }
static const GUID getServiceGuid() { return ThreadPoolGUID; }
public:
// Owner API:
ThreadPool();
void Kill();
// User API:
/* If you have multiple events, APCs, etc and you need them to always run on the same thread
you can reserve one */
ThreadID *ReserveThread(int flags);
/* Release a thread you've previously reserved */
void ReleaseThread(ThreadID *thread_id);
/* adds a waitable handle to the thread pool. when the event is signalled, your function ptr will get called
user_data and id values get passed to your function.
your function should return 1 to indicate that it can be removed
flags, see api_threadpool */
int AddHandle(ThreadID *threadid, HANDLE handle, api_threadpool::ThreadPoolFunc func, void *user_data, intptr_t id, int flags);
void RemoveHandle(ThreadID *threadid, HANDLE handle);
int RunFunction(ThreadID *threadid, api_threadpool::ThreadPoolFunc func, void *user_data, intptr_t id, int flags);
size_t GetNumberOfThreads(); // total number of threads in the threadpool
size_t GetNumberOfActiveThreads(); // number of threads that are currently being used (inside user function but not necessarily busy)
private:
enum
{
TYPE_MT = 0,
TYPE_STA = 1,
TYPE_MT_RESERVED = 2,
TYPE_STA_RESERVED = 3,
THREAD_TYPES = 4, // two thread types, single threaded apartment COM and multithreaded COM
};
private:
static DWORD CALLBACK WatchDogThreadProcedure_stub(LPVOID param);
ThreadID *CreateNewThread_Internal(int thread_type = 0);
DWORD CALLBACK WatchDogThreadProcedure();
static int GetThreadType(int flags, int reserved = 0);
static void GetThreadTypes(int flags, bool types[THREAD_TYPES]);
void RemoveHandle_Internal(size_t start, HANDLE handle); // recursive helper function for RemoveHandle()
void AddHandle_Internal(size_t start, HANDLE handle, int flags); // recursive helper function for RemoveHandle()
Nullsoft::Utility::LockGuard guard; // guards threads, any_thread_handles, and non_reserved_handles data structures
typedef std::vector<ThreadID*> ThreadList;
ThreadList threads;
ThreadPoolTypes::HandleList any_thread_handles[THREAD_TYPES];
HANDLE killswitch;
HANDLE watchdog_thread_handle;
volatile LONG num_threads_available[THREAD_TYPES];
ThreadFunctions thread_functions;
HANDLE max_load_event[THREAD_TYPES];
protected:
RECVS_DISPATCH;
};