GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: lib/libc/dlfcn/tib.c Lines: 0 10 0.0 %
Date: 2017-11-13 Branches: 0 0 0.0 %

Line Branch Exec Source
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/*	$OpenBSD: tib.c,v 1.1 2016/05/07 19:05:22 guenther Exp $ */
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/*
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 * Copyright (c) 2016 Philip Guenther <guenther@openbsd.org>
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 *
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 * Permission to use, copy, modify, and distribute this software for any
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 * purpose with or without fee is hereby granted, provided that the above
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 * copyright notice and this permission notice appear in all copies.
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 *
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 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
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 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
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 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
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 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
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 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
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 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
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 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
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 */
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#include <tib.h>
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#ifndef PIC
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# include <stdlib.h>		/* malloc and free */
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#endif
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#define ELF_ROUND(x,malign)	(((x) + (malign)-1) & ~((malign)-1))
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/*
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 * The functions here are weak so that the ld.so versions are used
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 * in dynamic links, whether or not libc is static
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 */
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void	*_dl_allocate_tib(size_t _extra) __attribute__((weak));
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void	_dl_free_tib(void *_tib, size_t _extra) __attribute__((weak));
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/*
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 * Allocate a TIB for passing to __tfork for a new thread.  'extra'
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 * is the amount of space to allocate on the side of the TIB opposite
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 * of the TLS data: before the TIB for variant 1 and after the TIB
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 * for variant 2.  If non-zero, tib_thread is set to point to that area.
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 */
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void *
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_dl_allocate_tib(size_t extra)
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{
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#ifdef PIC
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	return NULL;			/* overriden by ld.so */
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#else
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	char *base;
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	char *thread;
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	struct tib *tib;
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# if TLS_VARIANT == 1
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	/* round up the extra size to align the tib after it */
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	extra = ELF_ROUND(extra, sizeof(void *));
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	base = malloc(extra + sizeof(struct tib) + _static_tls_size);
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	tib = (struct tib *)(base + extra);
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	thread = base;
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# elif TLS_VARIANT == 2
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	/* round up the tib size to align the extra area after it */
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	base = malloc(ELF_ROUND(sizeof(struct tib), TIB_EXTRA_ALIGN) +
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	    extra + _static_tls_size);
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	tib = (struct tib *)(base + _static_tls_size);
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	thread = (char *)tib + ELF_ROUND(sizeof(struct tib), TIB_EXTRA_ALIGN);
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# endif
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	_static_tls_init(base);
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	TIB_INIT(tib, NULL, thread);
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	return (tib);
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#endif /* !PIC */
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}
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void
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_dl_free_tib(void *tib, size_t extra)
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{
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#ifndef PIC
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	size_t tib_offset;
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# if TLS_VARIANT == 1
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	tib_offset = ELF_ROUND(extra, sizeof(void *));
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# elif TLS_VARIANT == 2
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	tib_offset = _static_tls_size;
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# endif
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	free((char *)tib - tib_offset);
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#endif /* !PIC */
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}