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author | stanton <stanton> | 1999-04-16 00:46:29 (GMT) |
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committer | stanton <stanton> | 1999-04-16 00:46:29 (GMT) |
commit | 97464e6cba8eb0008cf2727c15718671992b913f (patch) | |
tree | ce9959f2747257d98d52ec8d18bf3b0de99b9535 /unix/tclUnixThrd.c | |
parent | a8c96ddb94d1483a9de5e340b740cb74ef6cafa7 (diff) | |
download | tcl-97464e6cba8eb0008cf2727c15718671992b913f.zip tcl-97464e6cba8eb0008cf2727c15718671992b913f.tar.gz tcl-97464e6cba8eb0008cf2727c15718671992b913f.tar.bz2 |
merged tcl 8.1 branch back into the main trunk
Diffstat (limited to 'unix/tclUnixThrd.c')
-rw-r--r-- | unix/tclUnixThrd.c | 682 |
1 files changed, 682 insertions, 0 deletions
diff --git a/unix/tclUnixThrd.c b/unix/tclUnixThrd.c new file mode 100644 index 0000000..b00bf42 --- /dev/null +++ b/unix/tclUnixThrd.c @@ -0,0 +1,682 @@ +/* + * 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. + * + * See the file "license.terms" for information on usage and redistribution + * of this file, and for a DISCLAIMER OF ALL WARRANTIES. + * + * SCCS: @(#) tclUnixThrd.c 1.18 98/02/19 14:24:12 + */ + +#include "tclInt.h" + +#ifdef TCL_THREADS + +#include "tclPort.h" +#include "pthread.h" + +/* + * 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; + +/* + * 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 */ + + + +#ifdef 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(idPtr, proc, clientData) + Tcl_ThreadId *idPtr; /* Return, the ID of the thread */ + Tcl_ThreadCreateProc proc; /* Main() function of the thread */ + ClientData clientData; /* The one argument to Main() */ +{ + pthread_attr_t attr; + + pthread_attr_init(&attr); + pthread_attr_setscope(&attr, PTHREAD_SCOPE_SYSTEM); + if (pthread_create((pthread_t *)idPtr, &attr, (void * (*)())proc, (void *)clientData) < 0) { + return TCL_ERROR; + } else { + return TCL_OK; + } +} + +/* + *---------------------------------------------------------------------- + * + * TclpThreadExit -- + * + * This procedure terminates the current thread. + * + * Results: + * None. + * + * Side effects: + * This procedure terminates the current thread. + * + *---------------------------------------------------------------------- + */ + +void +TclpThreadExit(status) + int status; +{ + pthread_exit((VOID *)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() +{ +#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() +{ +#ifdef TCL_THREADS + pthread_mutex_lock(&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() +{ +#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() +{ +#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() +{ +#ifdef TCL_THREADS + pthread_mutex_unlock(&masterLock); +#endif +} + +#ifdef TCL_THREADS + +/* + *---------------------------------------------------------------------- + * + * TclpMutexInit -- + * TclpMutexLock -- + * TclpMutexUnlock -- + * + * These procedures use an explicitly initialized mutex. + * These are used by memory allocators for their own mutex. + * + * Results: + * None. + * + * Side effects: + * Initialize, Lock, and Unlock the mutex. + * + *---------------------------------------------------------------------- + */ + +void +TclpMutexInit(mPtr) + TclpMutex *mPtr; +{ + pthread_mutex_init((pthread_mutex_t *)mPtr, NULL); +} +void +TclpMutexLock(mPtr) + TclpMutex *mPtr; +{ + pthread_mutex_lock((pthread_mutex_t *)mPtr); +} +void +TclpMutexUnlock(mPtr) + TclpMutex *mPtr; +{ + pthread_mutex_unlock((pthread_mutex_t *)mPtr); +} + +/* + *---------------------------------------------------------------------- + * + * 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(mutexPtr) + 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. + */ + + pmutexPtr = (pthread_mutex_t *)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); +} + + +/* + *---------------------------------------------------------------------- + * + * TclpMutexUnlock -- + * + * 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(mutexPtr) + 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(mutexPtr) + Tcl_Mutex *mutexPtr; +{ + pthread_mutex_t *pmutexPtr = *(pthread_mutex_t **)mutexPtr; + if (pmutexPtr != NULL) { + ckfree((char *)pmutexPtr); + *mutexPtr = NULL; + } +} + + +/* + *---------------------------------------------------------------------- + * + * TclpThreadDataKeyInit -- + * + * This procedure initializes a thread specific data block key. + * Each thread has table of pointers to thread specific data. + * all threads agree on which table entry is used by each module. + * this is remembered in a "data key", that is just an index into + * this table. To allow self initialization, the interface + * passes a pointer to this key and the first thread to use + * the key fills in the pointer to the key. The key should be + * a process-wide static. + * + * Results: + * None. + * + * Side effects: + * Will allocate memory the first time this process calls for + * this key. In this case it modifies its argument + * to hold the pointer to information about the key. + * + *---------------------------------------------------------------------- + */ + +void +TclpThreadDataKeyInit(keyPtr) + Tcl_ThreadDataKey *keyPtr; /* Identifier for the data chunk, + * really (pthread_key_t **) */ +{ + pthread_key_t *pkeyPtr; + + MASTER_LOCK; + if (*keyPtr == NULL) { + pkeyPtr = (pthread_key_t *)ckalloc(sizeof(pthread_key_t)); + pthread_key_create(pkeyPtr, NULL); + *keyPtr = (Tcl_ThreadDataKey)pkeyPtr; + TclRememberDataKey(keyPtr); + } + MASTER_UNLOCK; +} + +/* + *---------------------------------------------------------------------- + * + * TclpThreadDataKeyGet -- + * + * This procedure returns a pointer to a block of thread local storage. + * + * Results: + * A thread-specific pointer to the data structure, or NULL + * if the memory has not been assigned to this key for this thread. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +VOID * +TclpThreadDataKeyGet(keyPtr) + Tcl_ThreadDataKey *keyPtr; /* Identifier for the data chunk, + * really (pthread_key_t **) */ +{ + pthread_key_t *pkeyPtr = *(pthread_key_t **)keyPtr; + if (pkeyPtr == NULL) { + return NULL; + } else { + return (VOID *)pthread_getspecific(*pkeyPtr); + } +} + + +/* + *---------------------------------------------------------------------- + * + * TclpThreadDataKeySet -- + * + * This procedure sets the pointer to a block of thread local storage. + * + * Results: + * None. + * + * Side effects: + * Sets up the thread so future calls to TclpThreadDataKeyGet with + * this key will return the data pointer. + * + *---------------------------------------------------------------------- + */ + +void +TclpThreadDataKeySet(keyPtr, data) + Tcl_ThreadDataKey *keyPtr; /* Identifier for the data chunk, + * really (pthread_key_t **) */ + VOID *data; /* Thread local storage */ +{ + pthread_key_t *pkeyPtr = *(pthread_key_t **)keyPtr; + pthread_setspecific(*pkeyPtr, data); +} + +/* + *---------------------------------------------------------------------- + * + * TclpFinalizeThreadData -- + * + * This procedure cleans up the thread-local storage. This is + * called once for each thread. + * + * Results: + * None. + * + * Side effects: + * Frees up all thread local storage. + * + *---------------------------------------------------------------------- + */ + +void +TclpFinalizeThreadData(keyPtr) + Tcl_ThreadDataKey *keyPtr; +{ + VOID *result; + pthread_key_t *pkeyPtr; + + if (*keyPtr != NULL) { + pkeyPtr = *(pthread_key_t **)keyPtr; + result = (VOID *)pthread_getspecific(*pkeyPtr); + if (result != NULL) { + ckfree((char *)result); + pthread_setspecific(*pkeyPtr, (void *)NULL); + } + } +} + +/* + *---------------------------------------------------------------------- + * + * TclpFinalizeThreadDataKey -- + * + * This procedure is invoked to clean up one key. This is a + * process-wide storage identifier. The thread finalization code + * cleans up the thread local storage itself. + * + * This assumes the master lock is held. + * + * Results: + * None. + * + * Side effects: + * The key is deallocated. + * + *---------------------------------------------------------------------- + */ + +void +TclpFinalizeThreadDataKey(keyPtr) + Tcl_ThreadDataKey *keyPtr; +{ + pthread_key_t *pkeyPtr; + if (*keyPtr != NULL) { + pkeyPtr = *(pthread_key_t **)keyPtr; + pthread_key_delete(*pkeyPtr); + ckfree((char *)pkeyPtr); + *keyPtr = 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(condPtr, mutexPtr, timePtr) + Tcl_Condition *condPtr; /* Really (pthread_cond_t **) */ + Tcl_Mutex *mutexPtr; /* Really (pthread_mutex_t **) */ + 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 = (pthread_cond_t *)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 { + ptime.tv_sec = timePtr->sec + TclpGetSeconds(); + ptime.tv_nsec = 1000 * timePtr->usec; + 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(condPtr) + 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(condPtr) + Tcl_Condition *condPtr; +{ + pthread_cond_t *pcondPtr = *(pthread_cond_t **)condPtr; + if (pcondPtr != NULL) { + pthread_cond_destroy(pcondPtr); + ckfree((char *)pcondPtr); + *condPtr = NULL; + } +} + + + +#endif /* TCL_THREADS */ + |