/* spawn.cc

   Copyright 1996, 1997, 1998, 1999, 2000, 2001 Red Hat, Inc.

This file is part of Cygwin.

This software is a copyrighted work licensed under the terms of the
Cygwin license.  Please consult the file "CYGWIN_LICENSE" for
details. */

#include "winsup.h"
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <unistd.h>
#include <process.h>
#include <sys/wait.h>
#include <errno.h>
#include <limits.h>
#include <wingdi.h>
#include <winuser.h>
#include <ctype.h>
#include "cygerrno.h"
#include <sys/cygwin.h>
#include "perprocess.h"
#include "security.h"
#include "fhandler.h"
#include "path.h"
#include "dtable.h"
#include "sync.h"
#include "sigproc.h"
#include "cygheap.h"
#include "child_info.h"
#include "shared_info.h"
#include "pinfo.h"
#define NEED_VFORK
#include "perthread.h"
#include "registry.h"
#include "environ.h"

static char *envblockarg = (char *)NULL;
static suffix_info std_suffixes[] =
{
  suffix_info ("", 1),
  suffix_info (".exe", 1),
  suffix_info (NULL)
};

HANDLE hExeced;

/* Add .exe to PROG if not already present and see if that exists.
   If not, return PROG (converted from posix to win32 rules if necessary).
   The result is always BUF.

   Returns (possibly NULL) suffix */

static const char *
perhaps_suffix (const char *prog, path_conv &buf)
{
  TRACE_IN;
  char *ext;

  debug_printf ("prog '%s'", prog);
  buf.check (prog, PC_SYM_FOLLOW | PC_FULL, std_suffixes);

  if (buf.file_attributes () & FILE_ATTRIBUTE_DIRECTORY)
    ext = NULL;
  else if (buf.known_suffix)
    ext = buf + (buf.known_suffix - buf.get_win32 ());
  else
    ext = strchr (buf, '\0');

  debug_printf ("buf %s, suffix found '%s'", (char *) buf, ext);
  return ext;
}

/* Find an executable name, possibly by appending known executable
   suffixes to it.  The win32-translated name is placed in 'buf'.
   Any found suffix is returned in known_suffix.

   If the file is not found and !null_if_not_found then the win32 version
   of name is placed in buf and returned.  Otherwise the contents of buf
   is undefined and NULL is returned.  */

const char * __stdcall
find_exec (const char *name, path_conv& buf, const char *mywinenv,
	   int null_if_notfound, const char **known_suffix)
{
  TRACE_IN;
  const char *suffix = "";
  debug_printf ("find_exec (%s)", name);
  char *retval = buf;

  /* Check to see if file can be opened as is first.
     Win32 systems always check . first, but PATH may not be set up to
     do this. */
  if ((suffix = perhaps_suffix (name, buf)) != NULL)
    goto out;

  win_env *winpath;
  const char *path;
  char tmp[MAX_PATH];

  /* Return the error condition if this is an absolute path or if there
     is no PATH to search. */
  if (strchr (name, '/') || strchr (name, '\\') ||
      isdrive (name) ||
      !(winpath = getwinenv (mywinenv)) ||
      !(path = winpath->get_native ()) ||
      *path == '\0')
    goto errout;

  debug_printf ("%s%s", mywinenv, path);

  /* Iterate over the specified path, looking for the file with and
     without executable extensions. */
  do
    {
      char *eotmp = strccpy (tmp, &path, ';');
      /* An empty path or '.' means the current directory, but we've
	 already tried that.  */
      if (tmp[0] == '\0' || (tmp[0] == '.' && tmp[1] == '\0'))
	continue;

      *eotmp++ = '\\';
      strcpy (eotmp, name);

      debug_printf ("trying %s", tmp);

      if ((suffix = perhaps_suffix (tmp, buf)) != NULL)
	goto out;
    }
  while (*path && *++path);

 errout:
  /* Couldn't find anything in the given path.
     Take the appropriate action based on null_if_not_found. */
  if (null_if_notfound)
    retval = NULL;
  else
    buf.check (name);

 out:
  debug_printf ("%s = find_exec (%s)", (char *) buf, name);
  if (known_suffix)
    *known_suffix = suffix ?: strchr (buf, '\0');
  return retval;
}

/* Utility for spawn_guts.  */

static HANDLE
handle (int n, int direction)
{
  TRACE_IN;
  fhandler_base *fh = cygheap->fdtab[n];

  if (!fh)
    return INVALID_HANDLE_VALUE;
  if (fh->get_close_on_exec ())
    return INVALID_HANDLE_VALUE;
  if (direction == 0)
    return fh->get_handle ();
  return fh->get_output_handle ();
}

int
iscmd (const char *argv0, const char *what)
{
  TRACE_IN;
  int n;
  n = strlen (argv0) - strlen (what);
  if (n >= 2 && argv0[1] != ':')
    return 0;
  return n >= 0 && strcasematch (argv0 + n, what) &&
	 (n == 0 || isdirsep (argv0[n - 1]));
}

class linebuf
{
 private:
  size_t bufidx;
  size_t alloced;
 public:
  char *buf;
  linebuf () : bufidx (0), alloced (0), buf (NULL) {}
  ~linebuf () {/* if (buf) free (buf);*/}
  void add (const char *what, int len);
  void add (const char *what) {add (what, strlen (what));}
  void prepend (const char *what, int len);
  size_t idx() {return bufidx;}
};

void
linebuf::add (const char *what, int len)
{
  TRACE_IN;
  size_t nbufidx;
  if ((nbufidx = bufidx + len) >= alloced || !buf)
    {
      alloced += (MAX_PATH * 2) + nbufidx;
      buf = (char *) realloc (buf, alloced + 1);
    }
  memcpy (buf + bufidx, what, len);
  bufidx = nbufidx;
  buf[bufidx] = '\0';
}

void
linebuf::prepend (const char *what, int len)
{
  TRACE_IN;
  int buflen;
  size_t nbufidx;
  if ((nbufidx = bufidx + len) >= alloced)
    {
      alloced += (MAX_PATH * 2) + nbufidx;
      buf = (char *) realloc (buf, alloced + 1);
      buf[bufidx] = '\0';
    }
  if ((buflen = strlen (buf)))
      memmove (buf + len, buf, buflen + 1);
  else
      buf[nbufidx] = '\0';
  memcpy (buf, what, len);
  bufidx = nbufidx;
}

class av
{
  char **argv;
  int calloced;
 public:
  int argc;
  av (int ac, const char * const *av) : calloced (0), argc (ac)
  {
  TRACE_IN;
    argv = (char **) cmalloc (HEAP_1_ARGV, (argc + 5) * sizeof (char *));
    memcpy (argv, av, (argc + 1) * sizeof (char *));
  }
  ~av ()
  {
  TRACE_IN;
    for (int i = 0; i < calloced; i++)
      if (argv[i])
	cfree (argv[i]);
    if (argv)
      cfree (argv);
  }
  int unshift (const char *what, int conv = 0);
  operator char **() {TRACE_IN; return argv;}
  void all_calloced () {TRACE_IN; calloced = argc;}
  void replace0_maybe (const char *arg0)
  {
    /* Note: Assumes that argv array has not yet been "unshifted" */
  TRACE_IN;
    if (!calloced)
      {
	argv[0] = cstrdup1 (arg0);
	calloced = 1;
      }
  }
  void replace (int i, const char *arg)
    {
  TRACE_IN;
      argv[i] = cstrdup1 (arg);
    }
  void dup_maybe (int i)
  {
  TRACE_IN;
    if (i >= calloced)
      argv[i] = cstrdup1 (argv[i]);
  }
  void dup_all ()
  {
  TRACE_IN;
    for (int i = calloced; i < argc; i++)
      argv[i] = cstrdup1 (argv[i]);
  }
};

int
av::unshift (const char *what, int conv)
{
  TRACE_IN;
  char **av;
  av = (char **) crealloc (argv, (argc + 2) * sizeof (char *));
  if (!av)
    return 0;

  argv = av;
  memmove (argv + 1, argv, (argc + 1) * sizeof (char *));
  char buf[MAX_PATH + 1];
  if (conv)
    {
      cygwin_conv_to_posix_path (what, buf);
      char *p = strchr (buf, '\0') - 4;
      if (p > buf && strcasematch (p, ".exe"))
	*p = '\0';
      what = buf;
    }
  *argv = cstrdup1 (what);
  argc++;
  calloced++;
  return 1;
}

static int __stdcall
spawn_guts (HANDLE hToken, const char * prog_arg, const char *const *argv,
	    const char *const envp[], int mode)
{
  TRACE_IN;
  BOOL rc;
  bool ismsysdep;
  pid_t cygpid;
  sigframe thisframe (mainthread);
#if DEBUGGING
  for (int i=0;argv[i];i++)
      debug_printf("argv[%d] = %s", i, argv[i]);
#endif

  MALLOC_CHECK;

  if (prog_arg == NULL)
    {
      syscall_printf ("prog_arg is NULL");
      set_errno (EINVAL);
      return -1;
    }

  syscall_printf ("spawn_guts (%d, %.132s)", mode, prog_arg);

  if (argv == NULL)
    {
      syscall_printf ("argv is NULL");
      set_errno (EINVAL);
      return (-1);
    }

  path_conv real_path;

  class linebuf one_line;

  STARTUPINFO si = {0, NULL, NULL, NULL, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, NULL, NULL, NULL, NULL};

  child_info_spawn ciresrv;
  si.lpReserved2 = (LPBYTE) &ciresrv;
  si.cbReserved2 = sizeof (ciresrv) - 4; // Do not count the filler bytes

  DWORD chtype;
  if (mode != _P_OVERLAY && mode != _P_VFORK)
    chtype = PROC_SPAWN;
  else
    chtype = PROC_EXEC;

  HANDLE spr;
  if (mode != _P_OVERLAY)
    spr = NULL;
  else
    {
      spr = CreateEvent (&sec_all, TRUE, FALSE, NULL);
      ProtectHandle (spr);
    }

  init_child_info (chtype, &ciresrv, sizeof(ciresrv), (mode == _P_OVERLAY) ? myself->pid : 1, spr);
  if (!DuplicateHandle (hMainProc, hMainProc, hMainProc, &ciresrv.parent, 0, 1,
			DUPLICATE_SAME_ACCESS))
     {
       system_printf ("couldn't create handle to myself for child, %E");
       return -1;
     }

  ciresrv.moreinfo = (cygheap_exec_info *) ccalloc (HEAP_1_EXEC, 1, sizeof (cygheap_exec_info));
  ciresrv.moreinfo->old_title = NULL;

  /* CreateProcess takes one long string that is the command line (sigh).
     We need to quote any argument that has whitespace or embedded "'s.  */

  int ac;
  for (ac = 0; argv[ac]; ac++)
    /* nothing */;

  class av newargv (ac, argv);

  int null_app_name = 0;
  if (ac == 3 && argv[1][0] == '/' && argv[1][1] == 'c' &&
      (iscmd (argv[0], "command.com") || iscmd (argv[0], "cmd.exe")))
    {
      real_path.check (prog_arg);
      one_line.add ("\"");
      if (!real_path.error)
	one_line.add (real_path);
      else
	one_line.add (argv[0]);
      one_line.add ("\"");
      one_line.add (" ");
      one_line.add (argv[1]);
      one_line.add (" ");
      one_line.add (argv[2]);
      strcpy (real_path, argv[0]);
      null_app_name = 1;
      HMMM("skip_arg_parsing");
      goto skip_arg_parsing;
    }

  const char *ext;
  if ((ext = perhaps_suffix (prog_arg, real_path)) == NULL)
    {
      set_errno (ENOENT);
      return -1;
    }

  MALLOC_CHECK;

  /* If the file name ends in either .exe, .com, .bat, or .cmd we assume
     that it is NOT a script file */
  HMMM(ext);
  while (*ext == '\0')
    {
      HANDLE hnd = CreateFileA (real_path,
				GENERIC_READ,
				FILE_SHARE_READ | FILE_SHARE_WRITE,
				&sec_none_nih,
				OPEN_EXISTING,
				FILE_ATTRIBUTE_NORMAL,
				0);
      if (hnd == INVALID_HANDLE_VALUE)
	{
	  __seterrno ();
	  return -1;
	}

      DWORD done;

      char buf[2 * MAX_PATH + 1];
      buf[0] = buf[1] = buf[2] = buf[sizeof (buf) - 1] = '\0';
      if (!ReadFile (hnd, buf, sizeof (buf) - 1, &done, 0))
	{
	  CloseHandle (hnd);
	  __seterrno ();
	  return -1;
	}

      CloseHandle (hnd);

      if (buf[0] == 'M' && buf[1] == 'Z')
	break;

      debug_printf ("%s is a script", (char *) real_path);

      char *pgm, *arg1;

      if (buf[0] != '#' || buf[1] != '!')
	{
	  pgm = (char *) "/bin/sh";
	  arg1 = NULL;
	}
      else
	{
	  char *ptr;
	  pgm = buf + 2;
	  pgm += strspn (pgm, " \t");
	  for (ptr = pgm, arg1 = NULL;
	       *ptr && *ptr != '\r' && *ptr != '\n';
	       ptr++)
	    if (!arg1 && (*ptr == ' ' || *ptr == '\t'))
	      {
		/* Null terminate the initial command and step over
		   any additional white space.  If we've hit the
		   end of the line, exit the loop.  Otherwise, we've
		   found the first argument. Position the current
		   pointer on the last known white space. */
		*ptr = '\0';
		char *newptr = ptr + 1;
		newptr += strspn (newptr, " \t");
		if (!*newptr || *newptr == '\r' || *newptr == '\n')
		  break;
		arg1 = newptr;
		ptr = newptr - 1;
	      }

	  *ptr = '\0';
	}

      /* Replace argv[0] with the full path to the script if this is the
	 first time through the loop. */
      newargv.replace0_maybe (prog_arg);

      /* pointers:
       * pgm	interpreter name
       * arg1	optional string
       */
      if (arg1)
	newargv.unshift (arg1);

      find_exec (pgm, real_path, "PATH=", 0, &ext);
      newargv.unshift (real_path, 1);
      HMMM(ext);
    }

  FIXME;
  // iscygexec needs adjusted so that it truely identifies an MSYS executable.
  if (real_path.iscygexec ()) {
    newargv.dup_all ();
    ismsysdep = true;
  } else {
    ismsysdep = false;
      for (int i = 0; i < newargv.argc; i++)
	{
	  //convert argv to win32
	  int newargvlen = strlen (newargv[i]);
	  char *tmpbuf = (char *)malloc (newargvlen + 1);
	  memcpy (tmpbuf, newargv[i], newargvlen + 1);
	  tmpbuf = msys_p2w(tmpbuf);
	  debug_printf("newargv[%d] = %s", i, newargv[i]);
	  newargv.replace (i, tmpbuf);
	  free (tmpbuf);
	}
      FIXME; // Is the below loop necessary?
      // Well at least combine the above with it.
      for (int i = 0; i < newargv.argc; i++)
	{
	  char *p = NULL; // Temporary use pointer.
	  const char *a; // Pointer to newargv element.

	  if (i)
	    {
	      one_line.add (" ", 1);
	      MALLOC_CHECK;
	    }
	  newargv.dup_maybe (i);
	  a = i ? newargv[i] : (char *) real_path;
	  HMMM(a);
	  int len = strlen (a);
	  if (len != 0 && !strpbrk (a, " \t\n\r\""))
	    one_line.add (a, len);
	  else
	    {
	      one_line.add ("\"", 1);
	      /* Handle embedded special characters " and \.
		 A " is always preceded by a \.
		 A \ is not special unless it precedes a ".  If it does,
		 then all preceding \'s must be doubled to avoid having
		 the Windows command line parser interpret the \ as quoting
		 the ".  This rule applies to a string of \'s before the end
		 of the string, since cygwin/windows uses a " to delimit the
		 argument. */
	      for (; (p = strpbrk (a, "\"\\")); a = ++p)
		{
		  one_line.add (a, p - a);
		  /* Find length of string of backslashes */
		  int n = strspn (p, "\\");
		   /* No backslashes, so it must be a ".
		      The " has to be protected with a backslash. */
		  if (!n)
		    one_line.add ("\\\"", 2);	
		  else
		    {
		      one_line.add (p, n);	/* Add the run of backslashes */
		      /* Need to double up all of the preceding
			 backslashes if they precede a quote or EOS. */
		      if (!p[n] || p[n] == '"')
			one_line.add (p, n);
		      p += n - 1;		/* Point to last backslash */
		    }
		}
	      if (*a)
		one_line.add (a);
	      one_line.add ("\"", 1);
	    }
	  MALLOC_CHECK;
	}
#if 0
      FIXME;
      //    I renamed ix to bufidx and made it private.
      //    This is the only public place it's used.
      //    Null endings are handled by the linbuf class so I don't see this
      //      need.  If argv is funky in children then this is the culprit.
      MALLOC_CHECK;
      if (one_line.idx())
	one_line.buf[one_line.idx() - 1] = '\0';
      else
	one_line.add ("", 1);
      MALLOC_CHECK;
#endif
    }

  newargv.all_calloced ();
  ciresrv.moreinfo->argc = newargv.argc;
  ciresrv.moreinfo->argv = newargv;

  ciresrv.moreinfo->envc = envsize (envp, 1);
  ciresrv.moreinfo->envp = (char **) cmalloc (HEAP_1_ARGV, ciresrv.moreinfo->envc);
  ciresrv.hexec_proc = hexec_proc;
  char **c;
  const char * const *e;
  for (c = ciresrv.moreinfo->envp, e = envp; *e;)
    *c++ = cstrdup1 (*e++);
  *c = NULL;
  if (mode != _P_OVERLAY ||
      !DuplicateHandle (hMainProc, myself.shared_handle (), hMainProc,
			&ciresrv.moreinfo->myself_pinfo, 0,
			TRUE, DUPLICATE_SAME_ACCESS))
    ciresrv.moreinfo->myself_pinfo = NULL;

 skip_arg_parsing:
  PROCESS_INFORMATION pi = {NULL, 0, 0, 0};
  si.lpReserved = NULL;
  si.lpDesktop = NULL;
  si.dwFlags = STARTF_USESTDHANDLES;
  si.hStdInput = handle (0, 0); /* Get input handle */
  si.hStdOutput = handle (1, 1); /* Get output handle */
  si.hStdError = handle (2, 1); /* Get output handle */
  si.cb = sizeof (si);

  int flags = children_error_mode | GetPriorityClass (hMainProc);
  
  //FIXME: Is there good reason for this code?
  if (mode == _P_DETACH || !set_console_state_for_spawn ())
    flags |= DETACHED_PROCESS;
  if (mode != _P_OVERLAY)
    flags |= CREATE_SUSPENDED;

  /* Some file types (currently only sockets) need extra effort in the
     parent after CreateProcess and before copying the datastructures
     to the child. So we have to start the child in suspend state,
     unfortunately, to avoid a race condition. */
  if (cygheap->fdtab.need_fixup_before ())
    flags |= CREATE_SUSPENDED;


  /* Build windows style environment list */
  char *envblock;
  if (envblockarg)
    free (envblockarg);
  if (ismsysdep)
    envblockarg = winenv (envp, 1);
  else 
    envblockarg = winenv (envp, 0);

  /* Preallocated buffer for `sec_user' call */
  char sa_buf[1024];

  if (ismsysdep) {
    if (!hToken && cygheap->user.impersonated
	&& cygheap->user.token != INVALID_HANDLE_VALUE)
      hToken = cygheap->user.token;
  } else {
    hToken = NULL;
  }

  const char *runpath = null_app_name ? NULL : (const char *) real_path;

  syscall_printf ("spawn_guts null_app_name %d (%s, %.132s)", null_app_name, runpath, one_line.buf);

  cygbench ("spawn-guts");
  if (!hToken)
    {
      // The native process doesn't know about MSYS structures so don't fill
      // them in for native processes.
      if (ismsysdep) {
	ciresrv.moreinfo->uid = getuid ();
	FIXME;
	/* FIXME: This leaks a handle in the CreateProcessAsUser case since the
	   child process doesn't know about cygwin_mount_h. */
	ciresrv.mount_h = cygwin_mount_h;
	cygheap_setup_for_child (&ciresrv);
      }
      rc = CreateProcess (runpath,	/* image name - with full path */
			  one_line.buf,	/* what was passed to exec */
					  /* process security attrs */
			  allow_ntsec ? sec_user (sa_buf) : &sec_all_nih,
					  /* thread security attrs */
			  allow_ntsec ? sec_user (sa_buf) : &sec_all_nih,
			  TRUE,	/* inherit handles from parent */
			  flags,
			  envblockarg,/* environment */
			  0,	/* use current drive/directory */
			  &si,
			  &pi);
      
      if (!ismsysdep) {
	//FIXME: The child process needs help.  The stdout handle is blocking.
	//A child process that ismsysdep will execute initialization through
	// methods of fork_child in fork.cc.  A child process that !ismsysdep
	// doesn't have the opportunity to execute the fork_child method.
      }
    }
  else
    {
      cygsid sid;
      DWORD ret_len;
      if (!GetTokenInformation (hToken, TokenUser, &sid, sizeof sid, &ret_len))
	{
	  sid = NO_SID;
	  system_printf ("GetTokenInformation: %E");
	}
      /* Retrieve security attributes before setting psid to NULL
	 since it's value is needed by `sec_user'. */
      PSECURITY_ATTRIBUTES sec_attribs = allow_ntsec && sid
					 ? sec_user (sa_buf, sid)
					 : &sec_all_nih;

      /* Remove impersonation */
      if (cygheap->user.impersonated
	  && cygheap->user.token != INVALID_HANDLE_VALUE)
	RevertToSelf ();

      static BOOL first_time = TRUE;
      if (first_time)
	{
	  set_process_privilege (SE_RESTORE_NAME);
	  first_time = FALSE;
	}

      /* Load users registry hive. */
      load_registry_hive (sid);

      /* allow the child to interact with our window station/desktop */
      HANDLE hwst, hdsk;
      SECURITY_INFORMATION dsi = DACL_SECURITY_INFORMATION;
      DWORD n;
      char wstname[1024];
      char dskname[1024];

      ciresrv.moreinfo->uid = USHRT_MAX;
      hwst = GetProcessWindowStation ();
      SetUserObjectSecurity (hwst, &dsi, get_null_sd ());
      GetUserObjectInformation (hwst, UOI_NAME, wstname, 1024, &n);
      hdsk = GetThreadDesktop (GetCurrentThreadId ());
      SetUserObjectSecurity (hdsk, &dsi, get_null_sd ());
      GetUserObjectInformation (hdsk, UOI_NAME, dskname, 1024, &n);
      strcat (wstname, "\\");
      strcat (wstname, dskname);
      si.lpDesktop = wstname;

      cygheap_setup_for_child (&ciresrv);
      rc = CreateProcessAsUser (hToken,
		       runpath,		/* image name - with full path */
		       one_line.buf,	/* what was passed to exec */
		       sec_attribs,     /* process security attrs */
		       sec_attribs,     /* thread security attrs */
		       TRUE,	/* inherit handles from parent */
		       flags,
		       envblockarg,/* environment */
		       0,	/* use current drive/directory */
		       &si,
		       &pi);
      /* Restore impersonation. In case of _P_OVERLAY this isn't
	 allowed since it would overwrite child data. */
      if (mode != _P_OVERLAY && mode != _P_VFORK
	  && cygheap->user.impersonated
	  && cygheap->user.token != INVALID_HANDLE_VALUE)
	ImpersonateLoggedOnUser (cygheap->user.token);
    }

  MALLOC_CHECK;

  cygheap_setup_for_child_cleanup (&ciresrv);
  MALLOC_CHECK;

  /* Set errno now so that debugging messages from it appear before our
     final debugging message [this is a general rule for debugging
     messages].  */
  if (!rc)
    {
      __seterrno ();
      syscall_printf ("CreateProcess failed, %E");
      if (spr)
	ForceCloseHandle (spr);
      return -1;
    }

  /* Fixup the parent datastructure if needed and resume the child's
     main thread. */
  if (cygheap->fdtab.need_fixup_before ())
    {
      cygheap->fdtab.fixup_before_exec (pi.dwProcessId);
      if (mode == _P_OVERLAY)
	ResumeThread (pi.hThread);
    }

  if (mode == _P_OVERLAY)
    cygpid = myself->pid;
  else
    cygpid = cygwin_pid (pi.dwProcessId);

  /* We print the original program name here so the user can see that too.  */
  syscall_printf ("%d = spawn_guts (%s, %.132s)",
		  rc ? cygpid : (unsigned int) -1, prog_arg, one_line.buf);

  /* Name the handle similarly to proc_subproc. */
  ProtectHandle1 (pi.hProcess, childhProc);

  if (mode == _P_OVERLAY)
    {
      /* These are both duplicated in the child code.  We do this here,
	 primarily for strace. */
      strace.execing = 1;
      hExeced = pi.hProcess;
      strcpy (myself->progname, real_path);
      close_all_files ();
    }
  else
    {
      myself->set_has_pgid_children ();
      ProtectHandle (pi.hThread);
      pinfo child (cygpid, 1);
      if (!child)
	{
	  set_errno (EAGAIN);
	  syscall_printf ("-1 = spawnve (), process table full");
	  return -1;
	}
      child->dwProcessId = pi.dwProcessId;
      child->hProcess = pi.hProcess;
      child.remember ();
      strcpy (child->progname, real_path);
      (void) DuplicateHandle (hMainProc, child.shared_handle (), pi.hProcess,
			      NULL, 0, 0, DUPLICATE_SAME_ACCESS);
      /* Start the child running */
      ResumeThread (pi.hThread);
    }

  ForceCloseHandle (pi.hThread);

  sigproc_printf ("spawned windows pid %d", pi.dwProcessId);

  if (hToken && hToken != cygheap->user.token)
    CloseHandle (hToken);

  DWORD res;
  BOOL exited;

  res = 0;
  exited = FALSE;
  MALLOC_CHECK;
  if (mode == _P_OVERLAY)
    {
      int nwait = 3;
      HANDLE waitbuf[3] = {pi.hProcess, signal_arrived, spr};
      for (int i = 0; i < 100; i++)
	{
	  switch (WaitForMultipleObjects (nwait, waitbuf, FALSE, INFINITE))
	    {
	    case WAIT_OBJECT_0:
	      sigproc_printf ("subprocess exited");
	      DWORD exitcode;
	      if (!GetExitCodeProcess (pi.hProcess, &exitcode))
		exitcode = 1;
	      res |= exitcode;
	      exited = TRUE;
	      break;
	    case WAIT_OBJECT_0 + 1:
	      sigproc_printf ("signal arrived");
	      reset_signal_arrived ();
	      continue;
	    case WAIT_OBJECT_0 + 2:
	      if (myself->ppid_handle)
		res |= EXIT_REPARENTING;
	      if (!my_parent_is_alive ())
		{
		  nwait = 2;
		  sigproc_terminate ();
		  continue;
		}
	      break;
	    case WAIT_FAILED:
	      system_printf ("wait failed: nwait %d, pid %d, winpid %d, %E",
			     nwait, myself->pid, myself->dwProcessId);
	      system_printf ("waitbuf[0] %p %d", waitbuf[0],
			     WaitForSingleObject (waitbuf[0], 0));
	      system_printf ("waitbuf[1] %p = %d", waitbuf[1],
			     WaitForSingleObject (waitbuf[1], 0));
	      system_printf ("waitbuf[w] %p = %d", waitbuf[2],
			     WaitForSingleObject (waitbuf[2], 0));
	      set_errno (ECHILD);
	      try_to_debug ();
	      return -1;
	    }
	  break;
	}

      ForceCloseHandle (spr);

      sigproc_printf ("res = %x", res);

      if (res & EXIT_REPARENTING)
	{
	  /* Try to reparent child process.
	   * Make handles to child available to parent process and exit with
	   * EXIT_REPARENTING status. Wait() syscall in parent will then wait
	   * for newly created child.
	   */
	  HANDLE oldh = myself->hProcess;
	  HANDLE h = myself->ppid_handle;
	  sigproc_printf ("parent handle %p", h);
	  int rc = DuplicateHandle (hMainProc, pi.hProcess, h, &myself->hProcess,
				    0, FALSE, DUPLICATE_SAME_ACCESS);
	  sigproc_printf ("%d = DuplicateHandle, oldh %p, newh %p",
			  rc, oldh, myself->hProcess);
	  if (!rc && my_parent_is_alive ())
	    {
	      system_printf ("Reparent failed, parent handle %p, %E", h);
	      system_printf ("my dwProcessId %d, myself->dwProcessId %d",
			     GetCurrentProcessId (), myself->dwProcessId);
	      system_printf ("old hProcess %p, hProcess %p", oldh, myself->hProcess);
	    }
	}

    }

  MALLOC_CHECK;

  switch (mode)
    {
    case _P_OVERLAY:
      ForceCloseHandle1 (pi.hProcess, childhProc);
      proc_terminate ();
      myself->exit (res, 1);
      break;
    case _P_WAIT:
      waitpid (cygpid, (int *) &res, 0);
      break;
    case _P_DETACH:
      res = 0;	/* Lose all memory of this child. */
      break;
    case _P_NOWAIT:
    case _P_NOWAITO:
    case _P_VFORK:
      res = cygpid;
      break;
    default:
      break;
    }

  return (int) res;
}

extern "C" int
cwait (int *result, int pid, int)
{
  TRACE_IN;
  return waitpid (pid, result, 0);
}

/*
 * Helper function for spawn runtime calls.
 * Doesn't search the path.
 */

extern "C" int
_spawnve (HANDLE hToken, int mode, const char *path, const char *const *argv,
	  const char *const *envp)
{
  TRACE_IN;
  int ret;
  vfork_save *vf = vfork_storage.val ();
#if DEBUGGING
  for (int i=0;argv[i];i++)
      debug_printf("argv[%d] = %s", i, argv[i]);
#endif

  if (vf != NULL && (vf->pid < 0) && mode == _P_OVERLAY)
    mode = _P_NOWAIT;
  else
    vf = NULL;

  syscall_printf ("_spawnve (%s, %s, %x)", path, argv[0], envp);

  switch (mode)
    {
    case _P_OVERLAY:
      /* We do not pass _P_SEARCH_PATH here. execve doesn't search PATH.*/
      /* Just act as an exec if _P_OVERLAY set. */
      spawn_guts (hToken, path, argv, envp, mode);
      /* Errno should be set by spawn_guts.  */
      ret = -1;
      break;
    case _P_VFORK:
    case _P_NOWAIT:
    case _P_NOWAITO:
    case _P_WAIT:
    case _P_DETACH:
      subproc_init ();
      ret = spawn_guts (hToken, path, argv, envp, mode);
      if (vf && ret > 0)
	{
	  debug_printf ("longjmping due to vfork");
	  vf->pid = ret;
	  longjmp (vf->j, 1);
	}
      break;
    default:
      set_errno (EINVAL);
      ret = -1;
      break;
    }
  return ret;
}

/*
 * spawn functions as implemented in the MS runtime library.
 * Most of these based on (and copied from) newlib/libc/posix/execXX.c
 */

extern "C" int
spawnl (int mode, const char *path, const char *arg0, ...)
{
  TRACE_IN;
  int i;
  va_list args;
  const char *argv[256];

  va_start (args, arg0);
  argv[0] = arg0;
  i = 1;

  do
    {
      argv[i] = va_arg (args, const char *);
#if DEBUGGING
      debug_printf("argv[%d] = %s", i, argv[i]);
#endif
    }
  while (argv[i++] != NULL);

  va_end (args);

  return _spawnve (NULL, mode, path, (char * const  *) argv, cur_environ ());
}

extern "C" int
spawnle (int mode, const char *path, const char *arg0, ...)
{
  TRACE_IN;
  int i;
  va_list args;
  const char * const *envp;
  const char *argv[256];

  va_start (args, arg0);
  argv[0] = arg0;
  i = 1;

  do
    {
      argv[i] = va_arg (args, const char *);
#if DEBUGGING
      debug_printf("argv[%d] = %s", i, argv[i]);
#endif
    }
  while (argv[i++] != NULL);

  envp = va_arg (args, const char * const *);
  va_end (args);

  return _spawnve (NULL, mode, path, (char * const *) argv,
		   (char * const *) envp);
}

extern "C" int
spawnlp (int mode, const char *path, const char *arg0, ...)
{
  TRACE_IN;
  int i;
  va_list args;
  const char *argv[256];

  va_start (args, arg0);
  argv[0] = arg0;
  i = 1;

  do
    {
      argv[i] = va_arg (args, const char *);
#if DEBUGGING
      debug_printf("argv[%d] = %s", i, argv[i]);
#endif
    }
  while (argv[i++] != NULL);

  va_end (args);

  return spawnvpe (mode, path, (char * const *) argv, cur_environ ());
}

extern "C" int
spawnlpe (int mode, const char *path, const char *arg0, ...)
{
  TRACE_IN;
  int i;
  va_list args;
  const char * const *envp;
  const char *argv[256];

  va_start (args, arg0);
  argv[0] = arg0;
  i = 1;

  do
    {
      argv[i] = va_arg (args, const char *);
#if DEBUGGING
      debug_printf("argv[%d] = %s", i, argv[i]);
#endif
    }
  while (argv[i++] != NULL);

  envp = va_arg (args, const char * const *);
  va_end (args);

  return spawnvpe (mode, path, (char * const *) argv, envp);
}

extern "C" int
spawnv (int mode, const char *path, const char * const *argv)
{
  TRACE_IN;
#if DEBUGGING
  for (int i=0;argv[i];i++)
      debug_printf("argv[%d] = %s", i, argv[i]);
#endif
  return _spawnve (NULL, mode, path, argv, cur_environ ());
}

extern "C" int
spawnve (int mode, const char *path, char * const *argv,
					     const char * const *envp)
{
  TRACE_IN;
#if DEBUGGING
  for (int i=0;argv[i];i++)
      debug_printf("argv[%d] = %s", i, argv[i]);
#endif
  return _spawnve (NULL, mode, path, argv, envp);
}

extern "C" int
spawnvp (int mode, const char *path, const char * const *argv)
{
  TRACE_IN;
#if DEBUGGING
  for (int i=0;argv[i];i++)
      debug_printf("argv[%d] = %s", i, argv[i]);
#endif
  return spawnvpe (mode, path, argv, cur_environ ());
}

extern "C" int
spawnvpe (int mode, const char *file, const char * const *argv,
					     const char * const *envp)
{
  TRACE_IN;
  path_conv buf;
#if DEBUGGING
  for (int i=0;argv[i];i++)
      debug_printf("argv[%d] = %s", i, argv[i]);
#endif
  return _spawnve (NULL, mode, find_exec (file, buf), argv, envp);
}
