wait4 for the MiNTlib

[Andreas Schwab <schwab@issan.informatik.uni-dortmund.de>]

This is an implementation of wait4 for the MiNTlib.  Nothing special.

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/* wait4() emulation for MiNT, by Andreas Schwab.  From wait3.c by
   Eric R. Smith */

#include <types.h>
#include <wait.h>
#include <time.h>
#include <resource.h>
#include <mintbind.h>
#include <errno.h>
#include <signal.h>

extern int __mint;

extern long __waitval;		/* in thread.c */
extern long __waittime;		/* ditto */

__EXTERN void _bzero __PROTO ((void *, unsigned long));

/* in getrusage.c */
__EXTERN void _ms2tval __PROTO ((unsigned long, struct timeval *));

pid_t
wait4 (pid, status, options, rusage)
     pid_t pid;
     union wait *status;
     int options;
     struct rusage *rusage;
{
  long r, rsc[8];
  int exit_status, sig_term;

  if (__mint == 0)
    {
      r = __waitval;
      __waitval = -ENOENT;
      rsc[0] = __waittime;
      rsc[1] = rsc[4] = 0;
    }
  else
    r = Pwaitpid (pid, options, rsc);
  if (r < 0)
    {
      errno = (int) -r;
      return -1;
    }
  pid = (int) ((r & 0xffff0000L) >> 16);
  if (pid)
    {
      if (status)
	{
	  status->_i = 0;

	  if ((short) r == -32)
	    {
	      sig_term = SIGINT;
	      exit_status = 0;
	    }
	  else
	    {
	      exit_status = (int) r & 0xff;
	      sig_term = ((int) r & 0x7f00) >> 8;
	    }
	  if (sig_term >= NSIG)
	    sig_term = 0;
	  if (sig_term && exit_status != 0 && exit_status != 0177)
	    sig_term = 0;
	  if (exit_status == 0177 && sig_term)
	    {
	      status->w_termsig = WSTOPPED;
	      status->w_stopsig = sig_term;
	    }
	  else
	    {
	      status->w_termsig = sig_term;
	      status->w_retcode = exit_status;
	    }
	}
      if (rusage)
	{
	  _bzero (rusage, (unsigned long) sizeof (struct rusage));
	  _ms2tval (rsc[0], &rusage->ru_utime);
	  _ms2tval (rsc[1], &rusage->ru_stime);
	}
    }
  return pid;
}
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