2 * Copyright (c) 2004 Doug Rabson
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * $FreeBSD: src/libexec/rtld-elf/rtld_tls.h,v 1.1 2004/08/03 08:50:58 dfr Exp $
27 * $DragonFly: src/libexec/rtld-elf/Attic/rtld_tls.h,v 1.2 2005/03/28 03:33:17 dillon Exp $
31 * Semi-public interface from thread libraries to rtld for managing
39 * Allocate a TLS block for a new thread. The memory allocated will
40 * include 'tcbsize' bytes aligned to a 'tcbalign' boundary (in bytes)
41 * for the thread library's private purposes. The location of the TCB
42 * block is returned by this function. For architectures using
43 * 'Variant I' TLS, the thread local storage follows the TCB, and for
44 * 'Variant II', the thread local storage precedes it. For
45 * architectures using the 'Variant II' model (e.g. i386, amd64,
46 * sparc64), the TCB must begin with two pointer fields which are used
47 * by rtld for its TLS implementation. For the 'Variant I' model, the
48 * TCB must begin with a single pointer field for rtld's
51 * If the value of 'oldtls' is non-NULL, the new TLS block will be
52 * initialised using the values contained in 'oldtls' and 'oldtls'
53 * will be freed. This is typically used when initialising a thread
54 * library to migrate from using the initial bootstrap TLS block
55 * created by rtld to one which contains suitable thread library
58 * The value returned from this function is suitable for installing
59 * directly into the thread pointer register.
61 extern struct tls_tcb *_rtld_allocate_tls(struct tls_tcb *old_tls,
62 size_t tcb_size, int flags);
65 * Free a TLS block allocated using _rtld_allocate_tls(). The tcbsize
66 * and tcbalign parameters must be the same as those used to allocate
69 extern void _rtld_free_tls(struct tls_tcb *tcb, size_t tcb_size);