diff options
Diffstat (limited to 'win/tclWinThrd.c')
| -rw-r--r-- | win/tclWinThrd.c | 37 |
1 files changed, 35 insertions, 2 deletions
diff --git a/win/tclWinThrd.c b/win/tclWinThrd.c index 1c9d483..ae7ce80 100644 --- a/win/tclWinThrd.c +++ b/win/tclWinThrd.c @@ -24,6 +24,16 @@ _CRTIMP unsigned int __cdecl _controlfp (unsigned int unNew, unsigned int unMask #endif /* + * This is the number of milliseconds to wait between internal retries in + * the Tcl_MutexLock function. This value must be greater than or equal + * to zero and should be a suitable value for the given platform. + */ + +#ifndef TCL_MUTEX_LOCK_SLEEP_TIME +# define TCL_MUTEX_LOCK_SLEEP_TIME (0) +#endif + +/* * This is the master lock used to serialize access to other serialization * data structures. */ @@ -57,6 +67,13 @@ static int allocOnce = 0; #endif /* TCL_THREADS */ /* + * The mutexLock serializes Tcl_MutexLock. This is necessary to prevent + * races when finalizing a mutex that some other thread may want to lock. + */ + +static CRITICAL_SECTION mutexLock; + +/* * The joinLock serializes Create- and ExitThread. This is necessary to * prevent a race where a new joinable thread exits before the creating thread * had the time to create the necessary data structures in the emulation @@ -369,6 +386,7 @@ TclpInitLock(void) */ init = 1; + InitializeCriticalSection(&mutexLock); InitializeCriticalSection(&joinLock); InitializeCriticalSection(&initLock); InitializeCriticalSection(&masterLock); @@ -516,6 +534,7 @@ void TclFinalizeLock(void) { MASTER_LOCK; + DeleteCriticalSection(&mutexLock); DeleteCriticalSection(&joinLock); /* @@ -569,6 +588,8 @@ Tcl_MutexLock( { CRITICAL_SECTION *csPtr; +retry: + if (*mutexPtr == NULL) { MASTER_LOCK; @@ -584,8 +605,20 @@ Tcl_MutexLock( } MASTER_UNLOCK; } - csPtr = *((CRITICAL_SECTION **)mutexPtr); - EnterCriticalSection(csPtr); + while (1) { + EnterCriticalSection(&mutexLock); + csPtr = *((CRITICAL_SECTION **)mutexPtr); + if (csPtr == NULL) { + LeaveCriticalSection(&mutexLock); + goto retry; + } + if (TryEnterCriticalSection(csPtr)) { + LeaveCriticalSection(&mutexLock); + return; + } + LeaveCriticalSection(&mutexLock); + Tcl_Sleep(TCL_MUTEX_LOCK_SLEEP_TIME); + } } /* |