1 /* 2 * pthread_key_delete.c 3 * 4 * Description: 5 * POSIX thread functions which implement thread-specific data (TSD). 6 * 7 * -------------------------------------------------------------------------- 8 * 9 * Pthreads-win32 - POSIX Threads Library for Win32 10 * Copyright(C) 1998 John E. Bossom 11 * Copyright(C) 1999,2005 Pthreads-win32 contributors 12 * 13 * Contact Email: rpj (at) callisto.canberra.edu.au 14 * 15 * The current list of contributors is contained 16 * in the file CONTRIBUTORS included with the source 17 * code distribution. The list can also be seen at the 18 * following World Wide Web location: 19 * http://sources.redhat.com/pthreads-win32/contributors.html 20 * 21 * This library is free software; you can redistribute it and/or 22 * modify it under the terms of the GNU Lesser General Public 23 * License as published by the Free Software Foundation; either 24 * version 2 of the License, or (at your option) any later version. 25 * 26 * This library is distributed in the hope that it will be useful, 27 * but WITHOUT ANY WARRANTY; without even the implied warranty of 28 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 29 * Lesser General Public License for more details. 30 * 31 * You should have received a copy of the GNU Lesser General Public 32 * License along with this library in the file COPYING.LIB; 33 * if not, write to the Free Software Foundation, Inc., 34 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA 35 */ 36 37 #include "pthread.h" 38 #include "implement.h" 39 40 41 int 42 pthread_key_delete (pthread_key_t key) 43 /* 44 * ------------------------------------------------------ 45 * DOCPUBLIC 46 * This function deletes a thread-specific data key. This 47 * does not change the value of the thread specific data key 48 * for any thread and does not run the key's destructor 49 * in any thread so it should be used with caution. 50 * 51 * PARAMETERS 52 * key 53 * pointer to an instance of pthread_key_t 54 * 55 * 56 * DESCRIPTION 57 * This function deletes a thread-specific data key. This 58 * does not change the value of the thread specific data key 59 * for any thread and does not run the key's destructor 60 * in any thread so it should be used with caution. 61 * 62 * RESULTS 63 * 0 successfully deleted the key, 64 * EINVAL key is invalid, 65 * 66 * ------------------------------------------------------ 67 */ 68 { 69 ptw32_mcs_local_node_t keyLock; 70 int result = 0; 71 72 if (key != NULL) 73 { 74 if (key->threads != NULL && key->destructor != NULL) 75 { 76 ThreadKeyAssoc *assoc; 77 ptw32_mcs_lock_acquire (&(key->keyLock), &keyLock); 78 /* 79 * Run through all Thread<-->Key associations 80 * for this key. 81 * 82 * While we hold at least one of the locks guarding 83 * the assoc, we know that the assoc pointed to by 84 * key->threads is valid. 85 */ 86 while ((assoc = (ThreadKeyAssoc *) key->threads) != NULL) 87 { 88 ptw32_mcs_local_node_t threadLock; 89 ptw32_thread_t * thread = assoc->thread; 90 91 if (assoc == NULL) 92 { 93 /* Finished */ 94 break; 95 } 96 97 ptw32_mcs_lock_acquire (&(thread->threadLock), &threadLock); 98 /* 99 * Since we are starting at the head of the key's threads 100 * chain, this will also point key->threads at the next assoc. 101 * While we hold key->keyLock, no other thread can insert 102 * a new assoc via pthread_setspecific. 103 */ 104 ptw32_tkAssocDestroy (assoc); 105 ptw32_mcs_lock_release (&threadLock); 106 ptw32_mcs_lock_release (&keyLock); 107 } 108 } 109 110 TlsFree (key->key); 111 if (key->destructor != NULL) 112 { 113 /* A thread could be holding the keyLock */ 114 ptw32_mcs_lock_acquire (&(key->keyLock), &keyLock); 115 ptw32_mcs_lock_release (&keyLock); 116 } 117 118 #if defined( _DEBUG ) 119 memset ((char *) key, 0, sizeof (*key)); 120 #endif 121 free (key); 122 } 123 124 return (result); 125 } 126
