diff options
Diffstat (limited to 'plugins/YAMN/synchro.cpp')
| -rw-r--r-- | plugins/YAMN/synchro.cpp | 359 |
1 files changed, 0 insertions, 359 deletions
diff --git a/plugins/YAMN/synchro.cpp b/plugins/YAMN/synchro.cpp deleted file mode 100644 index e510d8bac9..0000000000 --- a/plugins/YAMN/synchro.cpp +++ /dev/null @@ -1,359 +0,0 @@ -/*
- * This code implements synchronization objects code between threads. If you want, you can include it to your
- * code. This file is not dependent on any other external code (functions)
- *
- * (c) majvan 2002-2004
- */
-
-#include "yamn.h"
-
-// Initializes a SWMRG structure. This structure must be
-// initialized before any writer or reader threads attempt
-// to wait on it.
-// The structure must be allocated by the application and
-// the structure's address is passed as the first parameter.
-// The lpszName parameter is the name of the object. Pass
-// NULL if you do not want to share the object.
-BOOL WINAPI SWMRGInitialize(PSWMRG pSWMRG,TCHAR *Name);
-
-// Deletes the system resources associated with a SWMRG
-// structure. The structure must be deleted only when
-// no writer or reader threads in the calling process
-// will wait on it.
-void WINAPI SWMRGDelete(PSWMRG pSWMRG);
-
-// A writer thread calls this function to know when
-// it can successfully write to the shared data.
-// returns WAIT_FINISH when we are in write-access or WAIT_FAILED
-// when event about quick finishing is set (or when system returns fail when waiting for synchro object)
-DWORD WINAPI SWMRGWaitToWrite(PSWMRG pSWMRG,DWORD dwTimeout);
-
-// A writer thread calls this function to let other threads
-// know that it no longer needs to write to the shared data.
-void WINAPI SWMRGDoneWriting(PSWMRG pSWMRG);
-
-// A reader thread calls this function to know when
-// it can successfully read the shared data.
-// returns WAIT_FINISH when we are in read-access or WAIT_FAILED
-// when event about quick finishing is set (or when system returns fail when waiting for synchro object)
-DWORD WINAPI SWMRGWaitToRead(PSWMRG pSWMRG, DWORD dwTimeout);
-
-// A reader thread calls this function to let other threads
-// know when it no longer needs to read the shared data.
-void WINAPI SWMRGDoneReading(PSWMRG pSWMRG);
-
-// WaitToReadFcn
-// is used to wait for read access with SWMRG SO, but it also increments counter if successfull
-// returns WAIT_FAILED or WAIT_FINISH
-// when WAIT_FAILED, we should not begin to access datas, we are not in read-access mode
-DWORD WINAPI WaitToReadFcn(PSWMRG SObject);
-
-// WriteDoneFcn
-// is used to release read access with SWMRG SO, but it also decrements counter if successfull
-void WINAPI ReadDoneFcn(PSWMRG SObject);
-
-// This functions is for export purposes
-// Plugin can call this function to manage SCOUNTER synchronization object
-
-// Gets number value stored in SCOUNTER SO
-// Note you must not read the number from memory directly, because
-// CPU can stop reading thread when it has read HI-Word, then another thread
-// can change the value and then OS starts the previous thread, that reads the
-// LO-WORD of DWORD. And the return value HI+LO-WORD is corrupted
-DWORD WINAPI SCGetNumberFcn(PSCOUNTER SCounter);
-
-// Increments SCOUNTER and unsets event
-// Returns Number after incrementing
-DWORD WINAPI SCIncFcn(PSCOUNTER SCounter);
-
-// Decrements SCOUNTER and sets event if zero
-// Returns Number after decrementing
-DWORD WINAPI SCDecFcn(PSCOUNTER SCounter);
-
-struct CExportedFunctions SynchroExportedFcn[]=
-{
- {YAMN_WAITTOWRITEID,(void *)WaitToWriteFcn},
- {YAMN_WRITEDONEID,(void *)WriteDoneFcn},
- {YAMN_WAITTOREADID,(void *)WaitToReadFcn},
- {YAMN_READDONEID,(void *)ReadDoneFcn},
- {YAMN_SCGETNUMBERID,(void *)SCGetNumberFcn},
- {YAMN_SCINCID,(void *)SCIncFcn},
- {YAMN_SCDECID,(void *)SCDecFcn},
-};
-
-//--------------------------------------------------------------------------------------------------
-//--------------------------------------------------------------------------------------------------
-
-void WINAPI SWMRGDelete(PSWMRG pSWMRG)
-{
-// Destroys any synchronization objects that were
-// successfully created.
- if (NULL!=pSWMRG->hEventNoWriter)
- CloseHandle(pSWMRG->hEventNoWriter);
- if (NULL!=pSWMRG->hEventNoReaders)
- CloseHandle(pSWMRG->hEventNoReaders);
- if (NULL!=pSWMRG->hSemNumReaders)
- CloseHandle(pSWMRG->hSemNumReaders);
- if (NULL!=pSWMRG->hFinishEV)
- CloseHandle(pSWMRG->hFinishEV);
-}
-
-BOOL WINAPI SWMRGInitialize(PSWMRG pSWMRG,TCHAR *Name)
-{
- pSWMRG->hEventNoWriter=NULL;
- pSWMRG->hEventNoReaders=NULL;
- pSWMRG->hSemNumReaders=NULL;
- pSWMRG->hFinishEV=NULL;
-
-// Creates the automatic-reset event that is signalled when
-// no writer threads are writing.
-// Initially no reader threads are reading.
- if (Name!=NULL)
- Name[0]=(TCHAR)'W';
- pSWMRG->hEventNoWriter=CreateEvent(NULL,FALSE,TRUE,Name);
-
-// Creates the manual-reset event that is signalled when
-// no reader threads are reading.
-// Initially no reader threads are reading.
- if (Name!=NULL)
- Name[0]=(TCHAR)'R';
- pSWMRG->hEventNoReaders=CreateEvent(NULL,TRUE,TRUE,Name);
-
-// Initializes the variable that indicates the number of
-// reader threads that are reading.
-// Initially no reader threads are reading.
- if (Name!=NULL)
- Name[0]=(TCHAR)'C';
- pSWMRG->hSemNumReaders=CreateSemaphore(NULL,0,0x7FFFFFFF,Name);
-
- if (Name!=NULL)
- Name[0]=(TCHAR)'F';
- pSWMRG->hFinishEV=CreateEvent(NULL,TRUE,FALSE,Name);
-
-// If a synchronization object could not be created,
-// destroys any created objects and return failure.
- if ((NULL==pSWMRG->hEventNoWriter) || (NULL==pSWMRG->hEventNoReaders) || (NULL==pSWMRG->hSemNumReaders) || (NULL==pSWMRG->hFinishEV))
- {
- SWMRGDelete(pSWMRG);
- return FALSE;
- }
- return TRUE;
-}
-
-DWORD WINAPI SWMRGWaitToWrite(PSWMRG pSWMRG,DWORD dwTimeout)
-{
- DWORD dw;
- HANDLE aHandles[2];
-
-// We can write if the following are true:
-// 1. No other threads are writing.
-// 2. No threads are reading.
-// But first we have to know if SWMRG structure is not about to delete
- aHandles[0]=pSWMRG->hEventNoWriter;
- aHandles[1]=pSWMRG->hEventNoReaders;
- if (WAIT_OBJECT_0==(dw=WaitForSingleObject(pSWMRG->hFinishEV,0)))
- return WAIT_FINISH;
- if (WAIT_FAILED==dw)
- return dw;
- dw=WaitForMultipleObjects(2,aHandles,TRUE,dwTimeout);
-// if a request to delete became later, we should not catch it. Try once more to ask if account is not about to delete
- if ((dw!=WAIT_FAILED) && (WAIT_OBJECT_0==(WaitForSingleObject(pSWMRG->hFinishEV,0))))
- {
- SetEvent(pSWMRG->hEventNoWriter);
- return WAIT_FINISH;
- }
-
-// This thread can write to the shared data.
-// Automatic event for NoWriter sets hEventNoWriter to nonsignaled after WaitForMultipleObject
-
-// Because a writer thread is writing, the Event
-// should not be reset. This stops other
-// writers and readers.
- return dw;
-}
-
-void WINAPI SWMRGDoneWriting(PSWMRG pSWMRG)
-// Presumably, a writer thread calling this function has
-// successfully called WaitToWrite. This means that we
-// do not have to wait on any synchronization objects
-// here because the writer already owns the Event.
-{
-// Allow other writer/reader threads to use
-// the SWMRG synchronization object.
- SetEvent(pSWMRG->hEventNoWriter);
-}
-
-DWORD WINAPI SWMRGWaitToRead(PSWMRG pSWMRG, DWORD dwTimeout)
-{
- DWORD dw;
- LONG lPreviousCount;
-
-// We can read if no threads are writing.
-// And there's not request to delete structure
- if (WAIT_OBJECT_0==(dw=WaitForSingleObject(pSWMRG->hFinishEV,0)))
- return WAIT_FINISH;
- if (WAIT_FAILED==dw)
- return dw;
- dw=WaitForSingleObject(pSWMRG->hEventNoWriter, dwTimeout);
-// if a request to delete became later, we should not catch it. Try once more to ask if account is not about to delete
- if ((dw!=WAIT_FAILED) && (WAIT_OBJECT_0==(WaitForSingleObject(pSWMRG->hFinishEV,0))))
- {
- SetEvent(pSWMRG->hEventNoWriter);
- return WAIT_FINISH;
- }
-
- if (dw==WAIT_OBJECT_0)
- {
- // This thread can read from the shared data.
- // Increment the number of reader threads.
- // But there can't be more than one thread incrementing readers,
- // so this is why we use semaphore.
- ReleaseSemaphore(pSWMRG->hSemNumReaders,1,&lPreviousCount);
- if (lPreviousCount==0)
- // If this is the first reader thread,
- // set event to reflect this. Other reader threads can read, no writer thread can write.
- ResetEvent(pSWMRG->hEventNoReaders);
-
- // Allow other writer/reader threads to use
- // the SWMRG synchronization object. hEventNoWrite is still non-signaled
- // (it looks like writer is processing thread, but it is not true)
- SetEvent(pSWMRG->hEventNoWriter);
- }
-
- return(dw);
-}
-
-void WINAPI SWMRGDoneReading(PSWMRG pSWMRG)
-{
- HANDLE aHandles[2];
- LONG lNumReaders;
-
-// We can stop reading if the events are available,
-// but when we stop reading we must also decrement the
-// number of reader threads.
- aHandles[0]=pSWMRG->hEventNoWriter;
- aHandles[1]=pSWMRG->hSemNumReaders;
- WaitForMultipleObjects(2,aHandles,TRUE,INFINITE);
-
-// Get the remaining number of readers by releasing the
-// semaphore and then restoring the count by immediately
-// performing a wait.
- ReleaseSemaphore(pSWMRG->hSemNumReaders,1,&lNumReaders);
- WaitForSingleObject(pSWMRG->hSemNumReaders,INFINITE);
-
-// If there are no remaining readers,
-// set the event to relect this.
- if (lNumReaders==0)
- // If there are no reader threads,
- // set our event to reflect this.
- SetEvent(pSWMRG->hEventNoReaders);
-
-// Allow other writer/reader threads to use
-// the SWMRG synchronization object.
-// (it looks like writer is processing thread, but it is not true)
- SetEvent(pSWMRG->hEventNoWriter);
-}
-
-DWORD WINAPI WaitToWriteFcn(PSWMRG SObject,PSCOUNTER SCounter)
-{
- DWORD EnterCode;
-#ifdef DEBUG_SYNCHRO
- DebugLog(SynchroFile,"\tSO WaitToWrite: %x\n",SObject);
-#endif
- if (WAIT_OBJECT_0==(EnterCode=SWMRGWaitToWrite(SObject,INFINITE)))
- if (SCounter!=NULL)
- SCIncFcn(SCounter);
- return EnterCode;
-}
-
-void WINAPI WriteDoneFcn(PSWMRG SObject,PSCOUNTER SCounter)
-{
-#ifdef DEBUG_SYNCHRO
- DebugLog(SynchroFile,"\tSO WriteDone: %x\n",SObject);
-#endif
- SWMRGDoneWriting(SObject);
- if (SCounter!=NULL)
- SCDecFcn(SCounter);
-}
-
-DWORD WINAPI WaitToReadFcn(PSWMRG SObject)
-{
- DWORD EnterCode;
-#ifdef DEBUG_SYNCHRO
- DebugLog(SynchroFile,"\tSO WaitToRead: %x\n",SObject);
-#endif
- EnterCode=SWMRGWaitToRead(SObject,INFINITE);
- return EnterCode;
-}
-
-void WINAPI ReadDoneFcn(PSWMRG SObject)
-{
-#ifdef DEBUG_SYNCHRO
- DebugLog(SynchroFile,"\tSO ReadDone: %x\n",SObject);
-#endif
- SWMRGDoneReading(SObject);
-}
-
-DWORD WINAPI SCGetNumberFcn(PSCOUNTER SCounter)
-{
- DWORD Temp;
-#ifdef DEBUG_SYNCHRO
- DebugLog(SynchroFile,"\tGetNumber-cs wait\n");
-#endif
- EnterCriticalSection(&SCounter->CounterCS);
-#ifdef DEBUG_SYNCHRO
- DebugLog(SynchroFile,"\tGetNumber-cs enter\n");
-#endif
- Temp=SCounter->Number;
-#ifdef DEBUG_SYNCHRO
- DebugLog(SynchroFile,"\tValue: %d\n",Temp);
- DebugLog(SynchroFile,"\tGetNumber-cs done\n");
-#endif
- LeaveCriticalSection(&SCounter->CounterCS);
- return Temp;
-}
-
-DWORD WINAPI SCIncFcn(PSCOUNTER SCounter)
-{
- DWORD Temp;
-#ifdef DEBUG_SYNCHRO
- DebugLog(SynchroFile,"\tIncrementValue-cs wait\n");
-#endif
- EnterCriticalSection(&SCounter->CounterCS);
-#ifdef DEBUG_SYNCHRO
- DebugLog(SynchroFile,"\tIncrementValue-cs enter\n");
-#endif
- Temp=++SCounter->Number;
- ResetEvent(SCounter->Event);
-#ifdef DEBUG_SYNCHRO
- DebugLog(SynchroFile,"\tValue: %d\n",Temp);
- DebugLog(SynchroFile,"\tIncrementValue-cs done\n");
-#endif
- LeaveCriticalSection(&SCounter->CounterCS);
- return Temp;
-}
-
-DWORD WINAPI SCDecFcn(PSCOUNTER SCounter)
-{
- DWORD Temp;
-#ifdef DEBUG_SYNCHRO
- DebugLog(SynchroFile,"\tDecrementValue-cs wait\n");
-#endif
- EnterCriticalSection(&SCounter->CounterCS);
-#ifdef DEBUG_SYNCHRO
- DebugLog(SynchroFile,"\tDecrementValue-cs enter\n");
-#endif
- if (!(Temp=--SCounter->Number))
- {
-#ifdef DEBUG_SYNCHRO
- DebugLog(SynchroFile,"\tDecrementValue-zero ev set\n");
-#endif
- SetEvent(SCounter->Event);
- }
-#ifdef DEBUG_SYNCHRO
- DebugLog(SynchroFile,"\tValue: %d\n",Temp);
- DebugLog(SynchroFile,"\tDecrementValue-cs done\n");
-#endif
- LeaveCriticalSection(&SCounter->CounterCS);
- return Temp;
-}
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