compilers/bcc/linux86-0.16.17/libc/misc/atexit.c

   1 /* Copyright (C) 1995,1996 Robert de Bath <rdebath@cix.compulink.co.uk>
   2  * This file is part of the Linux-8086 C library and is distributed
   3  * under the GNU Library General Public License.
   4  */
   5
   6 /*
   7  * This deals with both the atexit and on_exit function calls
   8  *
   9  * Note calls installed with atexit are called with the same args as on_exit
  10  * fuctions; the void* is given the NULL value.
  11  *
  12  */
  13
  14 #include <errno.h>
  15
  16 /* ATEXIT.H */
  17 #define MAXONEXIT 20            /* AIUI Posix requires 10 */
  18
  19 typedef void (*vfuncp) ();
  20
  21 extern vfuncp __cleanup;
  22 extern void __do_exit();
  23
  24 extern struct exit_table
  25 {
  26    vfuncp called;
  27    void *argument;
  28 }
  29 __on_exit_table[MAXONEXIT];
  30
  31 extern int __on_exit_count;
  32
  33 /* End ATEXIT.H */
  34
  35 #ifdef L_atexit
  36 int
  37 atexit(ptr)
  38 vfuncp ptr;
  39 {
  40    if( __on_exit_count < 0 || __on_exit_count >= MAXONEXIT)
  41    {
  42       errno = ENOMEM;
  43       return -1;
  44    }
  45    __cleanup = __do_exit;
  46    if( ptr )
  47    {
  48       __on_exit_table[__on_exit_count].called = ptr;
  49       __on_exit_table[__on_exit_count].argument = 0;
  50       __on_exit_count++;
  51    }
  52    return 0;
  53 }
  54
  55 #endif
  56
  57 #ifdef L_on_exit
  58 int
  59 on_exit(ptr, arg)
  60 vfuncp ptr;
  61 void *arg;
  62 {
  63    if( __on_exit_count < 0 || __on_exit_count >= MAXONEXIT)
  64    {
  65       errno = ENOMEM;
  66       return -1;
  67    }
  68    __cleanup = __do_exit;
  69    if( ptr )
  70    {
  71       __on_exit_table[__on_exit_count].called = ptr;
  72       __on_exit_table[__on_exit_count].argument = arg;
  73       __on_exit_count++;
  74    }
  75    return 0;
  76 }
  77
  78 #endif
  79
  80 #ifdef L___do_exit
  81
  82 int   __on_exit_count = 0;
  83 struct exit_table __on_exit_table[MAXONEXIT];
  84
  85 void
  86 __do_exit(rv)
  87 int   rv;
  88 {
  89    register int   count = __on_exit_count-1;
  90    register vfuncp ptr;
  91    __on_exit_count = -1;                /* ensure no more will be added */
  92    __cleanup = 0;                       /* Calling exit won't re-do this */
  93
  94    /* In reverse order */
  95    for (; count >= 0; count--)
  96    {
  97       ptr = __on_exit_table[count].called;
  98       (*ptr) (rv, __on_exit_table[count].argument);
  99    }
 100 }
 101
 102 #endif