stdlib/exit.c

   1 /* Copyright (C) 1991-2017 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <http://www.gnu.org/licenses/>.  */
  17
  18 #include <stdio.h>
  19 #include <stdlib.h>
  20 #include <unistd.h>
  21 #include <sysdep.h>
  22 #include "exit.h"
  23
  24 #include "set-hooks.h"
  25 DEFINE_HOOK (__libc_atexit, (void))
  26
  27
  28 /* Call all functions registered with `atexit' and `on_exit',
  29    in the reverse of the order in which they were registered
  30    perform stdio cleanup, and terminate program execution with STATUS.  */
  31 void
  32 attribute_hidden
  33 __run_exit_handlers (int status, struct exit_function_list **listp,
  34                      bool run_list_atexit, bool run_dtors)
  35 {
  36   /* First, call the TLS destructors.  */
  37 #ifndef SHARED
  38   if (&__call_tls_dtors != NULL)
  39 #endif
  40     if (run_dtors)
  41       __call_tls_dtors ();
  42
  43   /* We do it this way to handle recursive calls to exit () made by
  44      the functions registered with `atexit' and `on_exit'. We call
  45      everyone on the list and use the status value in the last
  46      exit (). */
  47   while (*listp != NULL)
  48     {
  49       struct exit_function_list *cur = *listp;
  50
  51       while (cur->idx > 0)
  52         {
  53           const struct exit_function *const f =
  54             &cur->fns[--cur->idx];
  55           switch (f->flavor)
  56             {
  57               void (*atfct) (void);
  58               void (*onfct) (int status, void *arg);
  59               void (*cxafct) (void *arg, int status);
  60
  61             case ef_free:
  62             case ef_us:
  63               break;
  64             case ef_on:
  65               onfct = f->func.on.fn;
  66 #ifdef PTR_DEMANGLE
  67               PTR_DEMANGLE (onfct);
  68 #endif
  69               onfct (status, f->func.on.arg);
  70               break;
  71             case ef_at:
  72               atfct = f->func.at;
  73 #ifdef PTR_DEMANGLE
  74               PTR_DEMANGLE (atfct);
  75 #endif
  76               atfct ();
  77               break;
  78             case ef_cxa:
  79               cxafct = f->func.cxa.fn;
  80 #ifdef PTR_DEMANGLE
  81               PTR_DEMANGLE (cxafct);
  82 #endif
  83               cxafct (f->func.cxa.arg, status);
  84               break;
  85             }
  86         }
  87
  88       *listp = cur->next;
  89       if (*listp != NULL)
  90         /* Don't free the last element in the chain, this is the statically
  91            allocate element.  */
  92         free (cur);
  93     }
  94
  95   if (run_list_atexit)
  96     RUN_HOOK (__libc_atexit, ());
  97
  98   _exit (status);
  99 }
 100
 101
 102 void
 103 exit (int status)
 104 {
 105   __run_exit_handlers (status, &__exit_funcs, true, true);
 106 }
 107 libc_hidden_def (exit)