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//==========================================================================;
//
// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY
// KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR
// PURPOSE.
//
// Copyright (c) 1992 - 1998 Microsoft Corporation. All Rights Reserved.
//
//--------------------------------------------------------------------------;
//
// helper classes and functions for building multimedia filters
//
#ifndef __WXUTIL__
#define __WXUTIL__
// eliminate spurious "statement has no effect" warnings.
#pragma warning(disable: 4705)
// wrapper for whatever critical section we have
class CCritSec {
// make copy constructor and assignment operator inaccessible
CCritSec(const CCritSec &refCritSec); CCritSec &operator=(const CCritSec &refCritSec);
CRITICAL_SECTION m_CritSec;
#ifdef DEBUG
public: DWORD m_currentOwner; DWORD m_lockCount; BOOL m_fTrace; // Trace this one
public: CCritSec(); ~CCritSec(); void Lock(); void Unlock(); #else
public: CCritSec() { InitializeCriticalSection(&m_CritSec); };
~CCritSec() { DeleteCriticalSection(&m_CritSec); };
void Lock() { EnterCriticalSection(&m_CritSec); };
void Unlock() { LeaveCriticalSection(&m_CritSec); }; #endif
};
//
// To make deadlocks easier to track it is useful to insert in the
// code an assertion that says whether we own a critical section or
// not. We make the routines that do the checking globals to avoid
// having different numbers of member functions in the debug and
// retail class implementations of CCritSec. In addition we provide
// a routine that allows usage of specific critical sections to be
// traced. This is NOT on by default - there are far too many.
//
#ifdef DEBUG
BOOL WINAPI CritCheckIn(CCritSec * pcCrit); BOOL WINAPI CritCheckOut(CCritSec * pcCrit); void WINAPI DbgLockTrace(BOOL fTrace); #else
#define CritCheckIn(x) TRUE
#define CritCheckOut(x) TRUE
#define DbgLockTrace(pc, fT)
#endif
// locks a critical section, and unlocks it automatically
// when the lock goes out of scope
class CAutoLock {
// make copy constructor and assignment operator inaccessible
CAutoLock(const CAutoLock &refAutoLock); CAutoLock &operator=(const CAutoLock &refAutoLock);
protected: CCritSec * m_pLock;
public: CAutoLock(CCritSec * plock) { m_pLock = plock; m_pLock->Lock(); };
~CAutoLock() { m_pLock->Unlock(); }; };
// wrapper for event objects
class CAMEvent {
// make copy constructor and assignment operator inaccessible
CAMEvent(const CAMEvent &refEvent); CAMEvent &operator=(const CAMEvent &refEvent);
protected: HANDLE m_hEvent; public: CAMEvent(BOOL fManualReset = FALSE); ~CAMEvent();
// Cast to HANDLE - we don't support this as an lvalue
operator HANDLE () const { return m_hEvent; };
void Set() {EXECUTE_ASSERT(SetEvent(m_hEvent));}; BOOL Wait(DWORD dwTimeout = INFINITE) { return (WaitForSingleObject(m_hEvent, dwTimeout) == WAIT_OBJECT_0); }; void Reset() { ResetEvent(m_hEvent); }; BOOL Check() { return Wait(0); }; };
// wrapper for event objects that do message processing
// This adds ONE method to the CAMEvent object to allow sent
// messages to be processed while waiting
class CAMMsgEvent : public CAMEvent {
public:
// Allow SEND messages to be processed while waiting
BOOL WaitMsg(DWORD dwTimeout = INFINITE); };
// old name supported for the time being
#define CTimeoutEvent CAMEvent
// support for a worker thread
// simple thread class supports creation of worker thread, synchronization
// and communication. Can be derived to simplify parameter passing
class AM_NOVTABLE CAMThread {
// make copy constructor and assignment operator inaccessible
CAMThread(const CAMThread &refThread); CAMThread &operator=(const CAMThread &refThread);
CAMEvent m_EventSend; CAMEvent m_EventComplete;
DWORD m_dwParam; DWORD m_dwReturnVal;
protected: HANDLE m_hThread;
// thread will run this function on startup
// must be supplied by derived class
virtual DWORD ThreadProc() = 0;
public: CAMThread(); ~CAMThread();
CCritSec m_AccessLock; // locks access by client threads
CCritSec m_WorkerLock; // locks access to shared objects
// thread initially runs this. param is actually 'this'. function
// just gets this and calls ThreadProc
static DWORD WINAPI InitialThreadProc(LPVOID pv);
// start thread running - error if already running
BOOL Create();
// signal the thread, and block for a response
//
DWORD CallWorker(DWORD);
// accessor thread calls this when done with thread (having told thread
// to exit)
void Close() { HANDLE hThread = (HANDLE)InterlockedExchangePointer(&m_hThread, 0); if (hThread) { WaitForSingleObject(hThread, INFINITE); CloseHandle(hThread); } };
// ThreadExists
// Return TRUE if the thread exists. FALSE otherwise
BOOL ThreadExists(void) const { if (m_hThread == 0) { return FALSE; } else { return TRUE; } }
// wait for the next request
DWORD GetRequest();
// is there a request?
BOOL CheckRequest(DWORD * pParam);
// reply to the request
void Reply(DWORD);
// If you want to do WaitForMultipleObjects you'll need to include
// this handle in your wait list or you won't be responsive
HANDLE GetRequestHandle() const { return m_EventSend; };
// Find out what the request was
DWORD GetRequestParam() const { return m_dwParam; };
// call CoInitializeEx (COINIT_DISABLE_OLE1DDE) if
// available. S_FALSE means it's not available.
static HRESULT CoInitializeHelper(); };
// CQueue
//
// Implements a simple Queue ADT. The queue contains a finite number of
// objects, access to which is controlled by a semaphore. The semaphore
// is created with an initial count (N). Each time an object is added
// a call to WaitForSingleObject is made on the semaphore's handle. When
// this function returns a slot has been reserved in the queue for the new
// object. If no slots are available the function blocks until one becomes
// available. Each time an object is removed from the queue ReleaseSemaphore
// is called on the semaphore's handle, thus freeing a slot in the queue.
// If no objects are present in the queue the function blocks until an
// object has been added.
#define DEFAULT_QUEUESIZE 2
template <class T> class CQueue { private: HANDLE hSemPut; // Semaphore controlling queue "putting"
HANDLE hSemGet; // Semaphore controlling queue "getting"
CRITICAL_SECTION CritSect; // Thread seriallization
int nMax; // Max objects allowed in queue
int iNextPut; // Array index of next "PutMsg"
int iNextGet; // Array index of next "GetMsg"
T *QueueObjects; // Array of objects (ptr's to void)
void Initialize(int n) { iNextPut = iNextGet = 0; nMax = n; InitializeCriticalSection(&CritSect); hSemPut = CreateSemaphore(NULL, n, n, NULL); hSemGet = CreateSemaphore(NULL, 0, n, NULL); QueueObjects = new T[n]; }
public: CQueue(int n) { Initialize(n); }
CQueue() { Initialize(DEFAULT_QUEUESIZE); }
~CQueue() { delete [] QueueObjects; DeleteCriticalSection(&CritSect); CloseHandle(hSemPut); CloseHandle(hSemGet); }
T GetQueueObject() { int iSlot; T Object; LONG lPrevious;
// Wait for someone to put something on our queue, returns straight
// away is there is already an object on the queue.
//
WaitForSingleObject(hSemGet, INFINITE);
EnterCriticalSection(&CritSect); iSlot = iNextGet++ % nMax; Object = QueueObjects[iSlot]; LeaveCriticalSection(&CritSect);
// Release anyone waiting to put an object onto our queue as there
// is now space available in the queue.
//
ReleaseSemaphore(hSemPut, 1L, &lPrevious); return Object; }
void PutQueueObject(T Object) { int iSlot; LONG lPrevious;
// Wait for someone to get something from our queue, returns straight
// away is there is already an empty slot on the queue.
//
WaitForSingleObject(hSemPut, INFINITE);
EnterCriticalSection(&CritSect); iSlot = iNextPut++ % nMax; QueueObjects[iSlot] = Object; LeaveCriticalSection(&CritSect);
// Release anyone waiting to remove an object from our queue as there
// is now an object available to be removed.
//
ReleaseSemaphore(hSemGet, 1L, &lPrevious); } };
// miscellaneous string conversion functions
// NOTE: as we need to use the same binaries on Win95 as on NT this code should
// be compiled WITHOUT unicode being defined. Otherwise we will not pick up
// these internal routines and the binary will not run on Win95.
int WINAPIV wsprintfWInternal(LPWSTR, LPCWSTR, ...);
LPWSTR WINAPI lstrcpyWInternal( LPWSTR lpString1, LPCWSTR lpString2 ); LPWSTR WINAPI lstrcpynWInternal( LPWSTR lpString1, LPCWSTR lpString2, int iMaxLength ); int WINAPI lstrcmpWInternal( LPCWSTR lpString1, LPCWSTR lpString2 ); int WINAPI lstrcmpiWInternal( LPCWSTR lpString1, LPCWSTR lpString2 ); int WINAPI lstrlenWInternal( LPCWSTR lpString );
#ifndef UNICODE
#define wsprintfW wsprintfWInternal
#define lstrcpyW lstrcpyWInternal
#define lstrcpynW lstrcpynWInternal
#define lstrcmpW lstrcmpWInternal
#define lstrcmpiW lstrcmpiWInternal
#define lstrlenW lstrlenWInternal
#endif
extern "C" void * __stdcall memmoveInternal(void *, const void *, size_t);
inline void * __cdecl memchrInternal(const void *buf, int chr, size_t cnt) { #ifdef _X86_
void *pRet = NULL;
_asm { cld // make sure we get the direction right
mov ecx, cnt // num of bytes to scan
mov edi, buf // pointer byte stream
mov eax, chr // byte to scan for
repne scasb // look for the byte in the byte stream
jnz exit_memchr // Z flag set if byte found
dec edi // scasb always increments edi even when it
// finds the required byte
mov pRet, edi exit_memchr: } return pRet;
#else
while ( cnt && (*(unsigned char *)buf != (unsigned char)chr) ) { buf = (unsigned char *)buf + 1; cnt--; }
return(cnt ? (void *)buf : NULL); #endif
}
void WINAPI IntToWstr(int i, LPWSTR wstr);
#define WstrToInt(sz) atoiW(sz)
inline int atoiW(const WCHAR *sz) { int i = 0;
while (*sz && *sz >= L'0' && *sz <= L'9') i = i*10 + *sz++ - L'0'; return i; }
inline int WINAPI atoiA(const CHAR *sz) { int i = 0;
while (*sz && *sz >= '0' && *sz <= '9') i = i*10 + *sz++ - '0'; return i; }
#ifdef UNICODE
#define atoi atoiW
#else
#define atoi atoiA
#endif
// These are available to help managing bitmap VIDEOINFOHEADER media structures
extern const DWORD bits555[3]; extern const DWORD bits565[3]; extern const DWORD bits888[3];
// These help convert between VIDEOINFOHEADER and BITMAPINFO structures
STDAPI_(const GUID) GetTrueColorType(const BITMAPINFOHEADER *pbmiHeader); STDAPI_(const GUID) GetBitmapSubtype(const BITMAPINFOHEADER *pbmiHeader); STDAPI_(WORD) GetBitCount(const GUID *pSubtype);
// strmbase.lib implements this for compatibility with people who
// managed to link to this directly. we don't want to advertise it.
//
// STDAPI_(/* T */ CHAR *) GetSubtypeName(const GUID *pSubtype);
STDAPI_(CHAR *) GetSubtypeNameA(const GUID *pSubtype); STDAPI_(WCHAR *) GetSubtypeNameW(const GUID *pSubtype);
#ifdef UNICODE
#define GetSubtypeName GetSubtypeNameW
#else
#define GetSubtypeName GetSubtypeNameA
#endif
STDAPI_(LONG) GetBitmapFormatSize(const BITMAPINFOHEADER *pHeader); STDAPI_(DWORD) GetBitmapSize(const BITMAPINFOHEADER *pHeader); STDAPI_(BOOL) ContainsPalette(const VIDEOINFOHEADER *pVideoInfo); STDAPI_(const RGBQUAD *) GetBitmapPalette(const VIDEOINFOHEADER *pVideoInfo);
// Compares two interfaces and returns TRUE if they are on the same object
BOOL WINAPI IsEqualObject(IUnknown *pFirst, IUnknown *pSecond);
// This is for comparing pins
#define EqualPins(pPin1, pPin2) IsEqualObject(pPin1, pPin2)
// Arithmetic helper functions
// Compute (a * b + rnd) / c
LONGLONG WINAPI llMulDiv(LONGLONG a, LONGLONG b, LONGLONG c, LONGLONG rnd); LONGLONG WINAPI Int64x32Div32(LONGLONG a, LONG b, LONG c, LONG rnd);
// Avoids us dyna-linking to SysAllocString to copy BSTR strings
STDAPI WriteBSTR(BSTR * pstrDest, LPCWSTR szSrc); STDAPI FreeBSTR(BSTR* pstr);
// Return a wide string - allocating memory for it
// Returns:
// S_OK - no error
// E_POINTER - ppszReturn == NULL
// E_OUTOFMEMORY - can't allocate memory for returned string
STDAPI AMGetWideString(LPCWSTR pszString, LPWSTR *ppszReturn);
// Special wait for objects owning windows
DWORD WINAPI WaitDispatchingMessages(HANDLE hObject, DWORD dwWait, HWND hwnd = NULL, UINT uMsg = 0); #endif /* __WXUTIL__ */
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