dmake/dbug/malloc/m_init.c

   1 /*
   2  * (c) Copyright 1990 Conor P. Cahill (uunet!virtech!cpcahil).
   3  * You may copy, distribute, and use this software as long as this
   4  * copyright statement is not removed.
   5  */
   6 #include <stdio.h>
   7 #include "malloc.h"
   8
   9 /*
  10  * Function:    malloc_init()
  11  *
  12  * Purpose:     to initialize the pointers and variables use by the
  13  *              malloc() debugging library
  14  *
  15  * Arguments:   none
  16  *
  17  * Returns:     nothing of any value
  18  *
  19  * Narrative:   Just initialize all the needed variables.  Use mallopt
  20  *              to set options taken from the environment.
  21  *
  22  */
  23 #ifndef lint
  24 static
  25 char rcs_hdr[] = "$Id: m_init.c,v 1.2 2006-07-25 10:08:07 rt Exp $";
  26 #endif
  27
  28 void
  29 malloc_init()
  30 {
  31     char                        * cptr;
  32     char                        * getenv();
  33     union malloptarg      m;
  34     extern char         * malloc_data_end;
  35     extern char         * malloc_data_start;
  36     extern struct mlist * malloc_end;
  37     extern struct mlist   malloc_start;
  38     char                        * sbrk();
  39
  40     /*
  41       * If already initialized...
  42      */
  43     if( malloc_data_start != (char *) 0)
  44     {
  45         return;
  46     }
  47
  48
  49     malloc_data_start = sbrk(0);
  50     malloc_data_end = malloc_data_start;
  51     malloc_start.s.size = 0;
  52     malloc_end = &malloc_start;
  53
  54     if( (cptr=getenv("MALLOC_WARN")) != NULL )
  55     {
  56         m.i = atoi(cptr);
  57         (void) mallopt(MALLOC_WARN,m);
  58     }
  59
  60     if( (cptr=getenv("MALLOC_FATAL")) != NULL)
  61     {
  62         m.i = atoi(cptr);
  63         (void) mallopt(MALLOC_FATAL,m);
  64     }
  65
  66     if( (cptr=getenv("MALLOC_CKCHAIN")) != NULL)
  67     {
  68         m.i = atoi(cptr);
  69         (void) mallopt(MALLOC_CKCHAIN,m);
  70     }
  71
  72     if( (cptr=getenv("MALLOC_ERRFILE")) != NULL)
  73     {
  74         m.str = cptr;
  75         (void) mallopt(MALLOC_ERRFILE,m);
  76     }
  77
  78 }
  79