1 /* libc-internal interface for thread-specific data. Stub or TLS version. 2 Copyright (C) 1998,2001,02 Free Software Foundation, Inc. 3 This file is part of the GNU C Library. 4 5 The GNU C Library is free software; you can redistribute it and/or 6 modify it under the terms of the GNU Lesser General Public 7 License as published by the Free Software Foundation; either 8 version 2.1 of the License, or (at your option) any later version. 9 10 The GNU C Library is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public 16 License along with the GNU C Library; if not, write to the Free 17 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 18 02111-1307 USA. */ 19 20 #ifndef _GENERIC_BITS_LIBC_TSD_H 21 #define _GENERIC_BITS_LIBC_TSD_H 1 22 23 /* This file defines the following macros for accessing a small fixed 24 set of thread-specific `void *' data used only internally by libc. 25 26 __libc_tsd_define(CLASS, KEY) -- Define or declare a `void *' datum 27 for KEY. CLASS can be `static' for 28 keys used in only one source file, 29 empty for global definitions, or 30 `extern' for global declarations. 31 __libc_tsd_address(KEY) -- Return the `void **' pointing to 32 the current thread's datum for KEY. 33 __libc_tsd_get(KEY) -- Return the `void *' datum for KEY. 34 __libc_tsd_set(KEY, VALUE) -- Set the datum for KEY to VALUE. 35 36 The set of available KEY's will usually be provided as an enum, 37 and contains (at least): 38 _LIBC_TSD_KEY_MALLOC 39 _LIBC_TSD_KEY_DL_ERROR 40 _LIBC_TSD_KEY_RPC_VARS 41 All uses must be the literal _LIBC_TSD_* name in the __libc_tsd_* macros. 42 Some implementations may not provide any enum at all and instead 43 using string pasting in the macros. */ 44 45 #include <TLS.h> 46 47 /* When full support for __thread variables is available, this interface is 48 just a trivial wrapper for it. Without TLS, this is the generic/stub 49 implementation for wholly single-threaded systems. 50 51 We don't define an enum for the possible key values, because the KEYs 52 translate directly into variables by macro magic. */ 53 54 #if USE___THREAD 55 # define __libc_tsd_define(CLASS, KEY) \ 56 CLASS __thread void *__libc_tsd_##KEY attribute_tls_model_ie; 57 58 # define __libc_tsd_address(KEY) (&__libc_tsd_##KEY) 59 # define __libc_tsd_get(KEY) (__libc_tsd_##KEY) 60 # define __libc_tsd_set(KEY, VALUE) (__libc_tsd_##KEY = (VALUE)) 61 #else 62 # define __libc_tsd_define(CLASS, KEY) CLASS void *__libc_tsd_##KEY##_data; 63 64 # define __libc_tsd_address(KEY) (&__libc_tsd_##KEY##_data) 65 # define __libc_tsd_get(KEY) (__libc_tsd_##KEY##_data) 66 # define __libc_tsd_set(KEY, VALUE) (__libc_tsd_##KEY##_data = (VALUE)) 67 #endif 68 69 #endif /* bits/libc-tsd.h */ 70