lib/libc/misc/initfini.c

   1 /*      $NetBSD: initfini.c,v 1.11 2013/08/19 22:14:37 matt Exp $        */
   2
   3 /*-
   4  * Copyright (c) 2007 The NetBSD Foundation, Inc.
   5  * All rights reserved.
   6  *
   7  * This code is derived from software contributed to The NetBSD Foundation
   8  * by Andrew Doran.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  29  * POSSIBILITY OF SUCH DAMAGE.
  30  */
  31
  32 #include <sys/cdefs.h>
  33 __RCSID("$NetBSD: initfini.c,v 1.11 2013/08/19 22:14:37 matt Exp $");
  34
  35 #ifdef _LIBC
  36 #include "namespace.h"
  37 #endif
  38
  39 #include <sys/param.h>
  40 #include <sys/exec.h>
  41 #include <sys/tls.h>
  42 #include <stdbool.h>
  43
  44 void    _libc_init(void) __attribute__((__constructor__, __used__));
  45
  46 void    __guard_setup(void);
  47 void    __libc_thr_init(void);
  48 void    __libc_atomic_init(void);
  49 void    __libc_atexit_init(void);
  50 void    __libc_env_init(void);
  51
  52 #if defined(__HAVE_TLS_VARIANT_I) || defined(__HAVE_TLS_VARIANT_II)
  53 __dso_hidden void       __libc_static_tls_setup(void);
  54 #endif
  55
  56 #ifdef __weak_alias
  57 __weak_alias(_dlauxinfo,___dlauxinfo)
  58 static void *__libc_dlauxinfo;
  59
  60 void *___dlauxinfo(void) __pure;
  61
  62 void *
  63 ___dlauxinfo(void)
  64 {
  65         return __libc_dlauxinfo;
  66 }
  67 #endif
  68
  69 static bool libc_initialised;
  70
  71 void _libc_init(void);
  72
  73 /*
  74  * Declare as common symbol to allow new libc with older binaries to
  75  * not trigger an undefined reference.
  76  */
  77 struct ps_strings *__ps_strings;
  78
  79 /*
  80  * _libc_init is called twice.  The first time explicitly by crt0.o
  81  * (for newer versions) and the second time as indirectly via _init().
  82  */
  83 void __section(".text.startup")
  84 _libc_init(void)
  85 {
  86
  87         if (libc_initialised)
  88                 return;
  89
  90         libc_initialised = 1;
  91
  92         if (__ps_strings != NULL)
  93                 __libc_dlauxinfo = __ps_strings->ps_argvstr +
  94                     __ps_strings->ps_nargvstr + __ps_strings->ps_nenvstr + 2;
  95
  96         /* For -fstack-protector */
  97         __guard_setup();
  98
  99 #if defined(__minix) && defined(_REENTRANT)
 100         /* Atomic operations */
 101         __libc_atomic_init();
 102 #endif /* defined(__minix) && defined(_REENTRANT) */
 103
 104 #if defined(__HAVE_TLS_VARIANT_I) || defined(__HAVE_TLS_VARIANT_II)
 105         /* Initialize TLS for statically linked programs. */
 106         __libc_static_tls_setup();
 107 #endif
 108
 109 #if defined(__minix) && defined(_REENTRANT)
 110         /* Threads */
 111         __libc_thr_init();
 112 #endif /* defined(__minix) && defined(_REENTRANT) */
 113
 114         /* Initialize the atexit mutexes */
 115         __libc_atexit_init();
 116
 117         /* Initialize environment memory RB tree. */
 118         __libc_env_init();
 119 }