| lh | 9ed821d | 2023-04-07 01:36:19 -0700 | [diff] [blame] | 1 | /* libc-internal interface for thread-specific data. Stub or TLS version. |
| 2 | Copyright (C) 1998-2015 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, see |
| 17 | <http://www.gnu.org/licenses/>. */ |
| 18 | |
| 19 | #ifndef _GENERIC_BITS_LIBC_TSD_H |
| 20 | #define _GENERIC_BITS_LIBC_TSD_H 1 |
| 21 | |
| 22 | /* This file defines the following macros for accessing a small fixed |
| 23 | set of thread-specific `void *' data used only internally by libc. |
| 24 | |
| 25 | __libc_tsd_define(CLASS, TYPE, KEY) -- Define or declare a datum with TYPE |
| 26 | for KEY. CLASS can be `static' for |
| 27 | keys used in only one source file, |
| 28 | empty for global definitions, or |
| 29 | `extern' for global declarations. |
| 30 | __libc_tsd_address(TYPE, KEY) -- Return the `TYPE *' pointing to |
| 31 | the current thread's datum for KEY. |
| 32 | __libc_tsd_get(TYPE, KEY) -- Return the `TYPE' datum for KEY. |
| 33 | __libc_tsd_set(TYPE, KEY, VALUE) -- Set the datum for KEY to VALUE. |
| 34 | |
| 35 | The set of available KEY's will usually be provided as an enum, |
| 36 | and contains (at least): |
| 37 | _LIBC_TSD_KEY_MALLOC |
| 38 | _LIBC_TSD_KEY_DL_ERROR |
| 39 | _LIBC_TSD_KEY_RPC_VARS |
| 40 | All uses must be the literal _LIBC_TSD_* name in the __libc_tsd_* macros. |
| 41 | Some implementations may not provide any enum at all and instead |
| 42 | using string pasting in the macros. */ |
| 43 | |
| 44 | #include <tls.h> |
| 45 | |
| 46 | /* When full support for __thread variables is available, this interface is |
| 47 | just a trivial wrapper for it. Without TLS, this is the generic/stub |
| 48 | implementation for wholly single-threaded systems. |
| 49 | |
| 50 | We don't define an enum for the possible key values, because the KEYs |
| 51 | translate directly into variables by macro magic. */ |
| 52 | |
| 53 | #define __libc_tsd_define(CLASS, TYPE, KEY) \ |
| 54 | CLASS __thread TYPE __libc_tsd_##KEY attribute_tls_model_ie; |
| 55 | |
| 56 | #define __libc_tsd_address(TYPE, KEY) (&__libc_tsd_##KEY) |
| 57 | #define __libc_tsd_get(TYPE, KEY) (__libc_tsd_##KEY) |
| 58 | #define __libc_tsd_set(TYPE, KEY, VALUE) (__libc_tsd_##KEY = (VALUE)) |
| 59 | |
| 60 | #endif /* bits/libc-tsd.h */ |