lib/csu/c++/c++rt0.c

   1 /*      $NetBSD: c++rt0.c,v 1.10 2005/12/24 22:02:10 perry Exp $        */
   2
   3 /*-
   4  * Copyright (c) 1998 The NetBSD Foundation, Inc.
   5  * All rights reserved.
   6  *
   7  * This code is derived from software contributed to The NetBSD Foundation
   8  * by Paul Kranenburg.
   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 /*
  33  * Run-time module for GNU C++ compiled shared libraries.
  34  *
  35  * The linker constructs the following arrays of pointers to global
  36  * constructors and destructors. The first element contains the
  37  * number of pointers in each.
  38  * The tables are also null-terminated.
  39  */
  40 #include <stdlib.h>
  41
  42
  43 /*
  44  * We make the __{C,D}TOR_LIST__ symbols appear as type `SETD' and
  45  * include a dummy local function in the set. This keeps references
  46  * to these symbols local to the shared object this module is linked to.
  47  */
  48 static void dummy __P((void)) { return; }
  49
  50 /* Note: this is "a.out" dependent. */
  51 __asm(".stabs \"___CTOR_LIST__\",22,0,0,_dummy");
  52 __asm(".stabs \"___DTOR_LIST__\",22,0,0,_dummy");
  53
  54 void (*__CTOR_LIST__[0]) __P((void));
  55 void (*__DTOR_LIST__[0]) __P((void));
  56
  57 static void     __dtors __P((void));
  58 static void     __ctors __P((void));
  59
  60 static void
  61 __dtors()
  62 {
  63         unsigned long i = (unsigned long) __DTOR_LIST__[0];
  64         void (**p)(void) = __DTOR_LIST__ + i;
  65
  66         while (i--)
  67                 (**p--)();
  68 }
  69
  70 static void
  71 __ctors()
  72 {
  73         unsigned long i = (unsigned long) __CTOR_LIST__[0];
  74         void (**p)(void) = __CTOR_LIST__ + 1;
  75
  76         while (i--)
  77                 (**p++)();
  78 }
  79
  80 extern void __init __P((void)) __asm(".init");
  81 extern void __fini __P((void)) __asm(".fini");
  82
  83 void
  84 __init()
  85 {
  86         static int initialized = 0;
  87
  88         /*
  89          * Call global constructors.
  90          * Arrange to call global destructors at exit.
  91          */
  92         if (!initialized) {
  93                 initialized = 1;
  94                 __ctors();
  95         }
  96
  97 }
  98
  99 void
 100 __fini()
 101 {
 102         /*
 103          * Call global destructors.
 104          */
 105         __dtors();
 106 }