diff options
Diffstat (limited to 'tcl8.6/unix/tclUnixThrd.c')
-rw-r--r-- | tcl8.6/unix/tclUnixThrd.c | 823 |
1 files changed, 823 insertions, 0 deletions
diff --git a/tcl8.6/unix/tclUnixThrd.c b/tcl8.6/unix/tclUnixThrd.c new file mode 100644 index 0000000..ea03332 --- /dev/null +++ b/tcl8.6/unix/tclUnixThrd.c @@ -0,0 +1,823 @@ +/* + * tclUnixThrd.c -- + * + * This file implements the UNIX-specific thread support. + * + * Copyright (c) 1991-1994 The Regents of the University of California. + * Copyright (c) 1994-1997 Sun Microsystems, Inc. + * Copyright (c) 2008 by George Peter Staplin + * + * See the file "license.terms" for information on usage and redistribution of + * this file, and for a DISCLAIMER OF ALL WARRANTIES. + */ + +#include "tclInt.h" + +#ifdef TCL_THREADS + +typedef struct ThreadSpecificData { + char nabuf[16]; +} ThreadSpecificData; + +static Tcl_ThreadDataKey dataKey; + +/* + * masterLock is used to serialize creation of mutexes, condition variables, + * and thread local storage. This is the only place that can count on the + * ability to statically initialize the mutex. + */ + +static pthread_mutex_t masterLock = PTHREAD_MUTEX_INITIALIZER; + +/* + * initLock is used to serialize initialization and finalization of Tcl. It + * cannot use any dyamically allocated storage. + */ + +static pthread_mutex_t initLock = PTHREAD_MUTEX_INITIALIZER; + +/* + * allocLock is used by Tcl's version of malloc for synchronization. For + * obvious reasons, cannot use any dyamically allocated storage. + */ + +static pthread_mutex_t allocLock = PTHREAD_MUTEX_INITIALIZER; +static pthread_mutex_t *allocLockPtr = &allocLock; + +/* + * These are for the critical sections inside this file. + */ + +#define MASTER_LOCK pthread_mutex_lock(&masterLock) +#define MASTER_UNLOCK pthread_mutex_unlock(&masterLock) + +#endif /* TCL_THREADS */ + +/* + *---------------------------------------------------------------------- + * + * TclpThreadCreate -- + * + * This procedure creates a new thread. + * + * Results: + * TCL_OK if the thread could be created. The thread ID is returned in a + * parameter. + * + * Side effects: + * A new thread is created. + * + *---------------------------------------------------------------------- + */ + +int +TclpThreadCreate( + Tcl_ThreadId *idPtr, /* Return, the ID of the thread */ + Tcl_ThreadCreateProc *proc, /* Main() function of the thread */ + ClientData clientData, /* The one argument to Main() */ + int stackSize, /* Size of stack for the new thread */ + int flags) /* Flags controlling behaviour of the new + * thread. */ +{ +#ifdef TCL_THREADS + pthread_attr_t attr; + pthread_t theThread; + int result; + + pthread_attr_init(&attr); + pthread_attr_setscope(&attr, PTHREAD_SCOPE_SYSTEM); + +#ifdef HAVE_PTHREAD_ATTR_SETSTACKSIZE + if (stackSize != TCL_THREAD_STACK_DEFAULT) { + pthread_attr_setstacksize(&attr, (size_t) stackSize); +#ifdef TCL_THREAD_STACK_MIN + } else { + /* + * Certain systems define a thread stack size that by default is too + * small for many operations. The user has the option of defining + * TCL_THREAD_STACK_MIN to a value large enough to work for their + * needs. This would look like (for 128K min stack): + * make MEM_DEBUG_FLAGS=-DTCL_THREAD_STACK_MIN=131072L + * + * This solution is not optimal, as we should allow the user to + * specify a size at runtime, but we don't want to slow this function + * down, and that would still leave the main thread at the default. + */ + + size_t size; + + result = pthread_attr_getstacksize(&attr, &size); + if (!result && (size < TCL_THREAD_STACK_MIN)) { + pthread_attr_setstacksize(&attr, (size_t) TCL_THREAD_STACK_MIN); + } +#endif /* TCL_THREAD_STACK_MIN */ + } +#endif /* HAVE_PTHREAD_ATTR_SETSTACKSIZE */ + + if (! (flags & TCL_THREAD_JOINABLE)) { + pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED); + } + + if (pthread_create(&theThread, &attr, + (void * (*)(void *))proc, (void *)clientData) && + pthread_create(&theThread, NULL, + (void * (*)(void *))proc, (void *)clientData)) { + result = TCL_ERROR; + } else { + *idPtr = (Tcl_ThreadId)theThread; + result = TCL_OK; + } + pthread_attr_destroy(&attr); + return result; +#else + return TCL_ERROR; +#endif /* TCL_THREADS */ +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_JoinThread -- + * + * This procedure waits upon the exit of the specified thread. + * + * Results: + * TCL_OK if the wait was successful, TCL_ERROR else. + * + * Side effects: + * The result area is set to the exit code of the thread we waited upon. + * + *---------------------------------------------------------------------- + */ + +int +Tcl_JoinThread( + Tcl_ThreadId threadId, /* Id of the thread to wait upon. */ + int *state) /* Reference to the storage the result of the + * thread we wait upon will be written into. + * May be NULL. */ +{ +#ifdef TCL_THREADS + int result; + unsigned long retcode, *retcodePtr = &retcode; + + result = pthread_join((pthread_t) threadId, (void**) retcodePtr); + if (state) { + *state = (int) retcode; + } + return (result == 0) ? TCL_OK : TCL_ERROR; +#else + return TCL_ERROR; +#endif +} + +#ifdef TCL_THREADS +/* + *---------------------------------------------------------------------- + * + * TclpThreadExit -- + * + * This procedure terminates the current thread. + * + * Results: + * None. + * + * Side effects: + * This procedure terminates the current thread. + * + *---------------------------------------------------------------------- + */ + +void +TclpThreadExit( + int status) +{ + pthread_exit(INT2PTR(status)); +} +#endif /* TCL_THREADS */ + +/* + *---------------------------------------------------------------------- + * + * Tcl_GetCurrentThread -- + * + * This procedure returns the ID of the currently running thread. + * + * Results: + * A thread ID. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +Tcl_ThreadId +Tcl_GetCurrentThread(void) +{ +#ifdef TCL_THREADS + return (Tcl_ThreadId) pthread_self(); +#else + return (Tcl_ThreadId) 0; +#endif +} + +/* + *---------------------------------------------------------------------- + * + * TclpInitLock + * + * This procedure is used to grab a lock that serializes initialization + * and finalization of Tcl. On some platforms this may also initialize + * the mutex used to serialize creation of more mutexes and thread local + * storage keys. + * + * Results: + * None. + * + * Side effects: + * Acquire the initialization mutex. + * + *---------------------------------------------------------------------- + */ + +void +TclpInitLock(void) +{ +#ifdef TCL_THREADS + pthread_mutex_lock(&initLock); +#endif +} + +/* + *---------------------------------------------------------------------- + * + * TclpFinalizeLock + * + * This procedure is used to destroy all private resources used in this + * file. + * + * Results: + * None. + * + * Side effects: + * Destroys everything private. TclpInitLock must be held entering this + * function. + * + *---------------------------------------------------------------------- + */ + +void +TclFinalizeLock(void) +{ +#ifdef TCL_THREADS + /* + * You do not need to destroy mutexes that were created with the + * PTHREAD_MUTEX_INITIALIZER macro. These mutexes do not need any + * destruction: masterLock, allocLock, and initLock. + */ + + pthread_mutex_unlock(&initLock); +#endif +} + +/* + *---------------------------------------------------------------------- + * + * TclpInitUnlock + * + * This procedure is used to release a lock that serializes + * initialization and finalization of Tcl. + * + * Results: + * None. + * + * Side effects: + * Release the initialization mutex. + * + *---------------------------------------------------------------------- + */ + +void +TclpInitUnlock(void) +{ +#ifdef TCL_THREADS + pthread_mutex_unlock(&initLock); +#endif +} + +/* + *---------------------------------------------------------------------- + * + * TclpMasterLock + * + * This procedure is used to grab a lock that serializes creation and + * finalization of serialization objects. This interface is only needed + * in finalization; it is hidden during creation of the objects. + * + * This lock must be different than the initLock because the initLock is + * held during creation of syncronization objects. + * + * Results: + * None. + * + * Side effects: + * Acquire the master mutex. + * + *---------------------------------------------------------------------- + */ + +void +TclpMasterLock(void) +{ +#ifdef TCL_THREADS + pthread_mutex_lock(&masterLock); +#endif +} + + +/* + *---------------------------------------------------------------------- + * + * TclpMasterUnlock + * + * This procedure is used to release a lock that serializes creation and + * finalization of synchronization objects. + * + * Results: + * None. + * + * Side effects: + * Release the master mutex. + * + *---------------------------------------------------------------------- + */ + +void +TclpMasterUnlock(void) +{ +#ifdef TCL_THREADS + pthread_mutex_unlock(&masterLock); +#endif +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_GetAllocMutex + * + * This procedure returns a pointer to a statically initialized mutex for + * use by the memory allocator. The alloctor must use this lock, because + * all other locks are allocated... + * + * Results: + * A pointer to a mutex that is suitable for passing to Tcl_MutexLock and + * Tcl_MutexUnlock. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +Tcl_Mutex * +Tcl_GetAllocMutex(void) +{ +#ifdef TCL_THREADS + pthread_mutex_t **allocLockPtrPtr = &allocLockPtr; + return (Tcl_Mutex *) allocLockPtrPtr; +#else + return NULL; +#endif +} + +#ifdef TCL_THREADS + +/* + *---------------------------------------------------------------------- + * + * Tcl_MutexLock -- + * + * This procedure is invoked to lock a mutex. This procedure handles + * initializing the mutex, if necessary. The caller can rely on the fact + * that Tcl_Mutex is an opaque pointer. This routine will change that + * pointer from NULL after first use. + * + * Results: + * None. + * + * Side effects: + * May block the current thread. The mutex is aquired when this returns. + * Will allocate memory for a pthread_mutex_t and initialize this the + * first time this Tcl_Mutex is used. + * + *---------------------------------------------------------------------- + */ + +void +Tcl_MutexLock( + Tcl_Mutex *mutexPtr) /* Really (pthread_mutex_t **) */ +{ + pthread_mutex_t *pmutexPtr; + + if (*mutexPtr == NULL) { + MASTER_LOCK; + if (*mutexPtr == NULL) { + /* + * Double inside master lock check to avoid a race condition. + */ + + pmutexPtr = ckalloc(sizeof(pthread_mutex_t)); + pthread_mutex_init(pmutexPtr, NULL); + *mutexPtr = (Tcl_Mutex)pmutexPtr; + TclRememberMutex(mutexPtr); + } + MASTER_UNLOCK; + } + pmutexPtr = *((pthread_mutex_t **)mutexPtr); + pthread_mutex_lock(pmutexPtr); +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_MutexUnlock -- + * + * This procedure is invoked to unlock a mutex. The mutex must have been + * locked by Tcl_MutexLock. + * + * Results: + * None. + * + * Side effects: + * The mutex is released when this returns. + * + *---------------------------------------------------------------------- + */ + +void +Tcl_MutexUnlock( + Tcl_Mutex *mutexPtr) /* Really (pthread_mutex_t **) */ +{ + pthread_mutex_t *pmutexPtr = *(pthread_mutex_t **) mutexPtr; + + pthread_mutex_unlock(pmutexPtr); +} + +/* + *---------------------------------------------------------------------- + * + * TclpFinalizeMutex -- + * + * This procedure is invoked to clean up one mutex. This is only safe to + * call at the end of time. + * + * This assumes the Master Lock is held. + * + * Results: + * None. + * + * Side effects: + * The mutex list is deallocated. + * + *---------------------------------------------------------------------- + */ + +void +TclpFinalizeMutex( + Tcl_Mutex *mutexPtr) +{ + pthread_mutex_t *pmutexPtr = *(pthread_mutex_t **) mutexPtr; + + if (pmutexPtr != NULL) { + pthread_mutex_destroy(pmutexPtr); + ckfree(pmutexPtr); + *mutexPtr = NULL; + } +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_ConditionWait -- + * + * This procedure is invoked to wait on a condition variable. The mutex + * is automically released as part of the wait, and automatically grabbed + * when the condition is signaled. + * + * The mutex must be held when this procedure is called. + * + * Results: + * None. + * + * Side effects: + * May block the current thread. The mutex is aquired when this returns. + * Will allocate memory for a pthread_mutex_t and initialize this the + * first time this Tcl_Mutex is used. + * + *---------------------------------------------------------------------- + */ + +void +Tcl_ConditionWait( + Tcl_Condition *condPtr, /* Really (pthread_cond_t **) */ + Tcl_Mutex *mutexPtr, /* Really (pthread_mutex_t **) */ + const Tcl_Time *timePtr) /* Timeout on waiting period */ +{ + pthread_cond_t *pcondPtr; + pthread_mutex_t *pmutexPtr; + struct timespec ptime; + + if (*condPtr == NULL) { + MASTER_LOCK; + + /* + * Double check inside mutex to avoid race, then initialize condition + * variable if necessary. + */ + + if (*condPtr == NULL) { + pcondPtr = ckalloc(sizeof(pthread_cond_t)); + pthread_cond_init(pcondPtr, NULL); + *condPtr = (Tcl_Condition) pcondPtr; + TclRememberCondition(condPtr); + } + MASTER_UNLOCK; + } + pmutexPtr = *((pthread_mutex_t **)mutexPtr); + pcondPtr = *((pthread_cond_t **)condPtr); + if (timePtr == NULL) { + pthread_cond_wait(pcondPtr, pmutexPtr); + } else { + Tcl_Time now; + + /* + * Make sure to take into account the microsecond component of the + * current time, including possible overflow situations. [Bug #411603] + */ + + Tcl_GetTime(&now); + ptime.tv_sec = timePtr->sec + now.sec + + (timePtr->usec + now.usec) / 1000000; + ptime.tv_nsec = 1000 * ((timePtr->usec + now.usec) % 1000000); + pthread_cond_timedwait(pcondPtr, pmutexPtr, &ptime); + } +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_ConditionNotify -- + * + * This procedure is invoked to signal a condition variable. + * + * The mutex must be held during this call to avoid races, but this + * interface does not enforce that. + * + * Results: + * None. + * + * Side effects: + * May unblock another thread. + * + *---------------------------------------------------------------------- + */ + +void +Tcl_ConditionNotify( + Tcl_Condition *condPtr) +{ + pthread_cond_t *pcondPtr = *((pthread_cond_t **)condPtr); + if (pcondPtr != NULL) { + pthread_cond_broadcast(pcondPtr); + } else { + /* + * Noone has used the condition variable, so there are no waiters. + */ + } +} + +/* + *---------------------------------------------------------------------- + * + * TclpFinalizeCondition -- + * + * This procedure is invoked to clean up a condition variable. This is + * only safe to call at the end of time. + * + * This assumes the Master Lock is held. + * + * Results: + * None. + * + * Side effects: + * The condition variable is deallocated. + * + *---------------------------------------------------------------------- + */ + +void +TclpFinalizeCondition( + Tcl_Condition *condPtr) +{ + pthread_cond_t *pcondPtr = *(pthread_cond_t **)condPtr; + + if (pcondPtr != NULL) { + pthread_cond_destroy(pcondPtr); + ckfree(pcondPtr); + *condPtr = NULL; + } +} +#endif /* TCL_THREADS */ + +/* + *---------------------------------------------------------------------- + * + * TclpReaddir, TclpInetNtoa -- + * + * These procedures replace core C versions to be used in a threaded + * environment. + * + * Results: + * See documentation of C functions. + * + * Side effects: + * See documentation of C functions. + * + * Notes: + * TclpReaddir is no longer used by the core (see 1095909), but it + * appears in the internal stubs table (see #589526). + * + *---------------------------------------------------------------------- + */ + +Tcl_DirEntry * +TclpReaddir( + DIR * dir) +{ + return TclOSreaddir(dir); +} + +#undef TclpInetNtoa +char * +TclpInetNtoa( + struct in_addr addr) +{ +#ifdef TCL_THREADS + ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey); + unsigned char *b = (unsigned char*) &addr.s_addr; + + sprintf(tsdPtr->nabuf, "%u.%u.%u.%u", b[0], b[1], b[2], b[3]); + return tsdPtr->nabuf; +#else + return inet_ntoa(addr); +#endif +} + +#ifdef TCL_THREADS +/* + * Additions by AOL for specialized thread memory allocator. + */ + +#ifdef USE_THREAD_ALLOC +static volatile int initialized = 0; +static pthread_key_t key; + +typedef struct allocMutex { + Tcl_Mutex tlock; + pthread_mutex_t plock; +} allocMutex; + +Tcl_Mutex * +TclpNewAllocMutex(void) +{ + struct allocMutex *lockPtr; + register pthread_mutex_t *plockPtr; + + lockPtr = malloc(sizeof(struct allocMutex)); + if (lockPtr == NULL) { + Tcl_Panic("could not allocate lock"); + } + plockPtr = &lockPtr->plock; + lockPtr->tlock = (Tcl_Mutex) plockPtr; + pthread_mutex_init(&lockPtr->plock, NULL); + return &lockPtr->tlock; +} + +void +TclpFreeAllocMutex( + Tcl_Mutex *mutex) /* The alloc mutex to free. */ +{ + allocMutex* lockPtr = (allocMutex*) mutex; + if (!lockPtr) { + return; + } + pthread_mutex_destroy(&lockPtr->plock); + free(lockPtr); +} + +void +TclpFreeAllocCache( + void *ptr) +{ + if (ptr != NULL) { + /* + * Called by the pthread lib when a thread exits + */ + + TclFreeAllocCache(ptr); + pthread_setspecific(key, NULL); + + } else if (initialized) { + /* + * Called by us in TclFinalizeThreadAlloc() during the library + * finalization initiated from Tcl_Finalize() + */ + + pthread_key_delete(key); + initialized = 0; + } +} + +void * +TclpGetAllocCache(void) +{ + if (!initialized) { + pthread_mutex_lock(allocLockPtr); + if (!initialized) { + pthread_key_create(&key, TclpFreeAllocCache); + initialized = 1; + } + pthread_mutex_unlock(allocLockPtr); + } + return pthread_getspecific(key); +} + +void +TclpSetAllocCache( + void *arg) +{ + pthread_setspecific(key, arg); +} +#endif /* USE_THREAD_ALLOC */ + +void * +TclpThreadCreateKey(void) +{ + pthread_key_t *ptkeyPtr; + + ptkeyPtr = TclpSysAlloc(sizeof *ptkeyPtr, 0); + if (NULL == ptkeyPtr) { + Tcl_Panic("unable to allocate thread key!"); + } + + if (pthread_key_create(ptkeyPtr, NULL)) { + Tcl_Panic("unable to create pthread key!"); + } + + return ptkeyPtr; +} + +void +TclpThreadDeleteKey( + void *keyPtr) +{ + pthread_key_t *ptkeyPtr = keyPtr; + + if (pthread_key_delete(*ptkeyPtr)) { + Tcl_Panic("unable to delete key!"); + } + + TclpSysFree(keyPtr); +} + +void +TclpThreadSetMasterTSD( + void *tsdKeyPtr, + void *ptr) +{ + pthread_key_t *ptkeyPtr = tsdKeyPtr; + + if (pthread_setspecific(*ptkeyPtr, ptr)) { + Tcl_Panic("unable to set master TSD value"); + } +} + +void * +TclpThreadGetMasterTSD( + void *tsdKeyPtr) +{ + pthread_key_t *ptkeyPtr = tsdKeyPtr; + + return pthread_getspecific(*ptkeyPtr); +} + +#endif /* TCL_THREADS */ + +/* + * Local Variables: + * mode: c + * c-basic-offset: 4 + * fill-column: 78 + * End: + */ |