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-rw-r--r--sysdeps/mach/hurd/spawni.c758
1 files changed, 0 insertions, 758 deletions
diff --git a/sysdeps/mach/hurd/spawni.c b/sysdeps/mach/hurd/spawni.c
deleted file mode 100644
index 74303839e4..0000000000
--- a/sysdeps/mach/hurd/spawni.c
+++ /dev/null
@@ -1,758 +0,0 @@
-/* spawn a new process running an executable.  Hurd version.
-   Copyright (C) 2001-2017 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU Lesser General Public License as
-   published by the Free Software Foundation; either version 2.1 of the
-   License, or (at your option) any later version.
-
-   The GNU C Library is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   Lesser General Public License for more details.
-
-   You should have received a copy of the GNU Lesser General Public
-   License along with the GNU C Library; see the file COPYING.LIB.  If
-   not, see <http://www.gnu.org/licenses/>.  */
-
-#include <errno.h>
-#include <fcntl.h>
-#include <paths.h>
-#include <spawn.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-#include <hurd.h>
-#include <hurd/signal.h>
-#include <hurd/fd.h>
-#include <hurd/id.h>
-#include <hurd/lookup.h>
-#include <hurd/resource.h>
-#include <assert.h>
-#include <argz.h>
-#include "spawn_int.h"
-
-/* Spawn a new process executing PATH with the attributes describes in *ATTRP.
-   Before running the process perform the actions described in FILE-ACTIONS. */
-int
-__spawni (pid_t *pid, const char *file,
-	  const posix_spawn_file_actions_t *file_actions,
-	  const posix_spawnattr_t *attrp,
-	  char *const argv[], char *const envp[],
-	  int xflags)
-{
-  pid_t new_pid;
-  char *path, *p, *name;
-  size_t len;
-  size_t pathlen;
-  short int flags;
-
-  /* The generic POSIX.1 implementation of posix_spawn uses fork and exec.
-     In traditional POSIX systems (Unix, Linux, etc), the only way to
-     create a new process is by fork, which also copies all the things from
-     the parent process that will be immediately wiped and replaced by the
-     exec.
-
-     This Hurd implementation works by doing an exec on a fresh task,
-     without ever doing all the work of fork.  The only work done by fork
-     that remains visible after an exec is registration with the proc
-     server, and the inheritance of various values and ports.  All those
-     inherited values and ports are what get collected up and passed in the
-     file_exec RPC by an exec call.  So we do the proc server registration
-     here, following the model of fork (see fork.c).  We then collect up
-     the inherited values and ports from this (parent) process following
-     the model of exec (see hurd/hurdexec.c), modify or replace each value
-     that fork would (plus the specific changes demanded by ATTRP and
-     FILE_ACTIONS), and make the file_exec RPC on the requested executable
-     file with the child process's task port rather than our own.  This
-     should be indistinguishable from the fork + exec implementation,
-     except that all errors will be detected here (in the parent process)
-     and return proper errno codes rather than the child dying with 127.
-
-     XXX The one exception to this supposed indistinguishableness is that
-     when posix_spawn_file_actions_addopen has been used, the parent
-     process can do various filesystem RPCs on the child's behalf, rather
-     than the child process doing it.  If these block due to a broken or
-     malicious filesystem server or just a blocked network fs or a serial
-     port waiting for carrier detect (!!), the parent's posix_spawn call
-     can block arbitrarily rather than just the child blocking.  Possible
-     solutions include:
-     * punt to plain fork + exec implementation if addopen was used
-     ** easy to do
-     ** gives up all benefits of this implementation in that case
-     * if addopen was used, don't do any file actions at all here;
-       instead, exec an installed helper program e.g.:
-	/libexec/spawn-helper close 3 dup2 1 2 open 0 /file 0x123 0666 exec /bin/foo foo a1 a2
-     ** extra exec might be more or less overhead than fork
-     * could do some weird half-fork thing where the child would inherit
-       our vm and run some code here, but not do the full work of fork
-
-     XXX Actually, the parent opens the executable file on behalf of
-     the child, and that has all the same issues.
-
-     I am favoring the half-fork solution.  That is, we do task_create with
-     vm inheritance, and we setjmp/longjmp the child like fork does.  But
-     rather than all the fork hair, the parent just packs up init/dtable
-     ports and does a single IPC to a receive right inserted in the child.  */
-
-  error_t err;
-  task_t task;
-  file_t execfile;
-  process_t proc;
-  auth_t auth;
-  int ints[INIT_INT_MAX];
-  file_t *dtable;
-  unsigned int dtablesize, orig_dtablesize, i;
-  struct hurd_port **dtable_cells;
-  char *dtable_cloexec;
-  struct hurd_userlink *ulink_dtable = NULL;
-  struct hurd_sigstate *ss;
-
-  /* For POSIX_SPAWN_RESETIDS, this reauthenticates our root/current
-     directory ports with the new AUTH port.  */
-  file_t rcrdir = MACH_PORT_NULL, rcwdir = MACH_PORT_NULL;
-  error_t reauthenticate (int which, file_t *result)
-    {
-      error_t err;
-      mach_port_t ref;
-      if (*result != MACH_PORT_NULL)
-	return 0;
-      ref = __mach_reply_port ();
-      err = HURD_PORT_USE
-	(&_hurd_ports[which],
-	 ({
-	   err = __io_reauthenticate (port, ref, MACH_MSG_TYPE_MAKE_SEND);
-	   if (!err)
-	     err = __auth_user_authenticate (auth,
-					     ref, MACH_MSG_TYPE_MAKE_SEND,
-					     result);
-	   err;
-	 }));
-      __mach_port_destroy (__mach_task_self (), ref);
-      return err;
-    }
-
-  /* Reauthenticate one of our file descriptors for the child.  A null
-     element of DTABLE_CELLS indicates a descriptor that was already
-     reauthenticated, or was newly opened on behalf of the child.  */
-  error_t reauthenticate_fd (int fd)
-    {
-      if (dtable_cells[fd] != NULL)
-	{
-	  file_t newfile;
-	  mach_port_t ref = __mach_reply_port ();
-	  error_t err = __io_reauthenticate (dtable[fd],
-					     ref, MACH_MSG_TYPE_MAKE_SEND);
-	  if (!err)
-	    err = __auth_user_authenticate (auth,
-					    ref, MACH_MSG_TYPE_MAKE_SEND,
-					    &newfile);
-	  __mach_port_destroy (__mach_task_self (), ref);
-	  if (err)
-	    return err;
-	  _hurd_port_free (dtable_cells[fd], &ulink_dtable[fd], dtable[fd]);
-	  dtable_cells[fd] = NULL;
-	  dtable[fd] = newfile;
-	}
-      return 0;
-    }
-
-  /* These callbacks are for looking up file names on behalf of the child.  */
-  error_t child_init_port (int which, error_t (*operate) (mach_port_t))
-    {
-      if (flags & POSIX_SPAWN_RESETIDS)
-	switch (which)
-	  {
-	  case INIT_PORT_AUTH:
-	    return (*operate) (auth);
-	  case INIT_PORT_CRDIR:
-	    return (reauthenticate (INIT_PORT_CRDIR, &rcrdir)
-		    ?: (*operate) (rcrdir));
-	  case INIT_PORT_CWDIR:
-	    return (reauthenticate (INIT_PORT_CWDIR, &rcwdir)
-		    ?: (*operate) (rcwdir));
-	  }
-      assert (which != INIT_PORT_PROC);
-      return _hurd_ports_use (which, operate);
-    }
-  file_t child_fd (int fd)
-    {
-      if ((unsigned int) fd < dtablesize && dtable[fd] != MACH_PORT_NULL)
-	{
-	  if (flags & POSIX_SPAWN_RESETIDS)
-	    {
-	      /* Reauthenticate this descriptor right now,
-		 since it is going to be used on behalf of the child.  */
-	      errno = reauthenticate_fd (fd);
-	      if (errno)
-		return MACH_PORT_NULL;
-	    }
-	  __mach_port_mod_refs (__mach_task_self (), dtable[fd],
-				MACH_PORT_RIGHT_SEND, +1);
-	  return dtable[fd];
-	}
-      errno = EBADF;
-      return MACH_PORT_NULL;
-    }
-  inline error_t child_lookup (const char *file, int oflag, mode_t mode,
-			       file_t *result)
-    {
-      return __hurd_file_name_lookup (&child_init_port, &child_fd, 0,
-				      file, oflag, mode, result);
-    }
-
-
-  /* Do this once.  */
-  flags = attrp == NULL ? 0 : attrp->__flags;
-
-  /* Generate the new process.  We create a task that does not inherit our
-     memory, and then register it as our child like fork does.  See fork.c
-     for comments about the sequencing of these proc operations.  */
-
-  err = __task_create (__mach_task_self (),
-#ifdef KERN_INVALID_LEDGER
-		       NULL, 0,	/* OSF Mach */
-#endif
-		       0, &task);
-  if (err)
-    return __hurd_fail (err);
-  // From here down we must deallocate TASK and PROC before returning.
-  proc = MACH_PORT_NULL;
-  auth = MACH_PORT_NULL;
-  err = __USEPORT (PROC, __proc_task2pid (port, task, &new_pid));
-  if (!err)
-    err = __USEPORT (PROC, __proc_task2proc (port, task, &proc));
-  if (!err)
-    err = __USEPORT (PROC, __proc_child (port, task));
-  if (err)
-    goto out;
-
-  /* Load up the ints to give the new program.  */
-  memset (ints, 0, sizeof ints);
-  ints[INIT_UMASK] = _hurd_umask;
-  ints[INIT_TRACEMASK] = _hurdsig_traced;
-
-  ss = _hurd_self_sigstate ();
-
-  assert (! __spin_lock_locked (&ss->critical_section_lock));
-  __spin_lock (&ss->critical_section_lock);
-
-  __spin_lock (&ss->lock);
-  ints[INIT_SIGMASK] = ss->blocked;
-  ints[INIT_SIGPENDING] = ss->pending;
-  ints[INIT_SIGIGN] = 0;
-  /* Unless we were asked to reset all handlers to SIG_DFL,
-     pass down the set of signals that were set to SIG_IGN.  */
-  if ((flags & POSIX_SPAWN_SETSIGDEF) == 0)
-    for (i = 1; i < NSIG; ++i)
-      if (ss->actions[i].sa_handler == SIG_IGN)
-	ints[INIT_SIGIGN] |= __sigmask (i);
-
-  /* We hold the sigstate lock until the exec has failed so that no signal
-     can arrive between when we pack the blocked and ignored signals, and
-     when the exec actually happens.  A signal handler could change what
-     signals are blocked and ignored.  Either the change will be reflected
-     in the exec, or the signal will never be delivered.  Setting the
-     critical section flag avoids anything we call trying to acquire the
-     sigstate lock.  */
-
-  __spin_unlock (&ss->lock);
-
-  /* Set signal mask.  */
-  if ((flags & POSIX_SPAWN_SETSIGMASK) != 0)
-    ints[INIT_SIGMASK] = attrp->__ss;
-
-#ifdef _POSIX_PRIORITY_SCHEDULING
-  /* Set the scheduling algorithm and parameters.  */
-# error implement me
-  if ((flags & (POSIX_SPAWN_SETSCHEDPARAM | POSIX_SPAWN_SETSCHEDULER))
-      == POSIX_SPAWN_SETSCHEDPARAM)
-    {
-      if (__sched_setparam (0, &attrp->__sp) == -1)
-	_exit (SPAWN_ERROR);
-    }
-  else if ((flags & POSIX_SPAWN_SETSCHEDULER) != 0)
-    {
-      if (__sched_setscheduler (0, attrp->__policy,
-				(flags & POSIX_SPAWN_SETSCHEDPARAM) != 0
-				? &attrp->__sp : NULL) == -1)
-	_exit (SPAWN_ERROR);
-    }
-#endif
-
-  if (!err && (flags & POSIX_SPAWN_SETSID) != 0)
-    err = __proc_setsid (proc);
-
-  /* Set the process group ID.  */
-  if (!err && (flags & POSIX_SPAWN_SETPGROUP) != 0)
-    err = __proc_setpgrp (proc, new_pid, attrp->__pgrp);
-
-  /* Set the effective user and group IDs.  */
-  if (!err && (flags & POSIX_SPAWN_RESETIDS) != 0)
-    {
-      /* We need a different auth port for the child.  */
-
-      __mutex_lock (&_hurd_id.lock);
-      err = _hurd_check_ids (); /* Get _hurd_id up to date.  */
-      if (!err && _hurd_id.rid_auth == MACH_PORT_NULL)
-	{
-	  /* Set up _hurd_id.rid_auth.  This is a special auth server port
-	     which uses the real uid and gid (the first aux uid and gid) as
-	     the only effective uid and gid.  */
-
-	  if (_hurd_id.aux.nuids < 1 || _hurd_id.aux.ngids < 1)
-	    /* We do not have a real UID and GID.  Lose, lose, lose!  */
-	    err = EGRATUITOUS;
-
-	  /* Create a new auth port using our real UID and GID (the first
-	     auxiliary UID and GID) as the only effective IDs.  */
-	  if (!err)
-	    err = __USEPORT (AUTH,
-			     __auth_makeauth (port,
-					      NULL, MACH_MSG_TYPE_COPY_SEND, 0,
-					      _hurd_id.aux.uids, 1,
-					      _hurd_id.aux.uids,
-					      _hurd_id.aux.nuids,
-					      _hurd_id.aux.gids, 1,
-					      _hurd_id.aux.gids,
-					      _hurd_id.aux.ngids,
-					      &_hurd_id.rid_auth));
-	}
-      if (!err)
-	{
-	  /* Use the real-ID auth port in place of the normal one.  */
-	  assert (_hurd_id.rid_auth != MACH_PORT_NULL);
-	  auth = _hurd_id.rid_auth;
-	  __mach_port_mod_refs (__mach_task_self (), auth,
-				MACH_PORT_RIGHT_SEND, +1);
-	}
-      __mutex_unlock (&_hurd_id.lock);
-    }
-  else
-    /* Copy our existing auth port.  */
-    err = __USEPORT (AUTH, __mach_port_mod_refs (__mach_task_self (),
-						 (auth = port),
-						 MACH_PORT_RIGHT_SEND, +1));
-
-  if (err)
-    goto out;
-
-  /* Pack up the descriptor table to give the new program.
-     These descriptors will need to be reauthenticated below
-     if POSIX_SPAWN_RESETIDS is set.  */
-  __mutex_lock (&_hurd_dtable_lock);
-  dtablesize = _hurd_dtablesize;
-  orig_dtablesize = _hurd_dtablesize;
-  dtable = __alloca (dtablesize * sizeof (dtable[0]));
-  ulink_dtable = __alloca (dtablesize * sizeof (ulink_dtable[0]));
-  dtable_cells = __alloca (dtablesize * sizeof (dtable_cells[0]));
-  dtable_cloexec = __alloca (dtablesize);
-  for (i = 0; i < dtablesize; ++i)
-    {
-      struct hurd_fd *const d = _hurd_dtable[i];
-      if (d == NULL)
-	{
-	  dtable[i] = MACH_PORT_NULL;
-	  dtable_cells[i] = NULL;
-	  continue;
-	}
-      /* Note that this might return MACH_PORT_NULL.  */
-      dtable[i] = _hurd_port_get (&d->port, &ulink_dtable[i]);
-      dtable_cells[i] = &d->port;
-      dtable_cloexec[i] = (d->flags & FD_CLOEXEC) != 0;
-    }
-  __mutex_unlock (&_hurd_dtable_lock);
-
-  /* Safe to let signals happen now.  */
-  _hurd_critical_section_unlock (ss);
-
-  /* Execute the file actions.  */
-  if (file_actions != NULL)
-    for (i = 0; i < file_actions->__used; ++i)
-      {
-	/* Close a file descriptor in the child.  */
-	error_t do_close (int fd)
-	  {
-	    if ((unsigned int)fd < dtablesize
-		&& dtable[fd] != MACH_PORT_NULL)
-	      {
-		if (dtable_cells[fd] == NULL)
-		  __mach_port_deallocate (__mach_task_self (), dtable[fd]);
-		else
-		  {
-		    _hurd_port_free (dtable_cells[fd],
-				     &ulink_dtable[fd], dtable[fd]);
-		  }
-		dtable_cells[fd] = NULL;
-		dtable[fd] = MACH_PORT_NULL;
-		return 0;
-	      }
-	    return EBADF;
-	  }
-
-	/* Make sure the dtable can hold NEWFD.  */
-#define EXPAND_DTABLE(newfd)						      \
-	({								      \
-	  if ((unsigned int)newfd >= dtablesize				      \
-	      && newfd < _hurd_rlimits[RLIMIT_OFILE].rlim_cur)		      \
-	    {								      \
-	      /* We need to expand the dtable for the child.  */	      \
-	      NEW_TABLE (dtable, newfd);				      \
-	      NEW_TABLE (ulink_dtable, newfd);				      \
-	      NEW_TABLE (dtable_cells, newfd);				      \
-	      dtablesize = newfd + 1;					      \
-	    }								      \
-	  ((unsigned int)newfd < dtablesize ? 0 : EMFILE);		      \
-	})
-#define NEW_TABLE(x, newfd) \
-  do { __typeof (x) new_##x = __alloca ((newfd + 1) * sizeof (x[0]));	      \
-  memcpy (new_##x, x, dtablesize * sizeof (x[0]));			      \
-  memset (&new_##x[dtablesize], 0, (newfd + 1 - dtablesize) * sizeof (x[0])); \
-  x = new_##x; } while (0)
-
-	struct __spawn_action *action = &file_actions->__actions[i];
-
-	switch (action->tag)
-	  {
-	  case spawn_do_close:
-	    err = do_close (action->action.close_action.fd);
-	    break;
-
-	  case spawn_do_dup2:
-	    if ((unsigned int)action->action.dup2_action.fd < dtablesize
-		&& dtable[action->action.dup2_action.fd] != MACH_PORT_NULL)
-	      {
-		const int fd = action->action.dup2_action.fd;
-		const int newfd = action->action.dup2_action.newfd;
-		// dup2 always clears any old FD_CLOEXEC flag on the new fd.
-		if (newfd < orig_dtablesize)
-		  dtable_cloexec[newfd] = 0;
-		if (fd == newfd)
-		  // Same is same as same was.
-		  break;
-		err = EXPAND_DTABLE (newfd);
-		if (!err)
-		  {
-		    /* Close the old NEWFD and replace it with FD's
-		       contents, which can be either an original
-		       descriptor (DTABLE_CELLS[FD] != 0) or a new
-		       right that we acquired in this function.  */
-		    do_close (newfd);
-		    dtable_cells[newfd] = dtable_cells[fd];
-		    if (dtable_cells[newfd] != NULL)
-		      dtable[newfd] = _hurd_port_get (dtable_cells[newfd],
-						      &ulink_dtable[newfd]);
-		    else
-		      {
-			dtable[newfd] = dtable[fd];
-			err = __mach_port_mod_refs (__mach_task_self (),
-						    dtable[fd],
-						    MACH_PORT_RIGHT_SEND, +1);
-		      }
-		  }
-	      }
-	    else
-	      // The old FD specified was bogus.
-	      err = EBADF;
-	    break;
-
-	  case spawn_do_open:
-	    /* Open a file on behalf of the child.
-
-	       XXX note that this can subject the parent to arbitrary
-	       delays waiting for the files to open.  I don't know what the
-	       spec says about this.  If it's not permissible, then this
-	       whole forkless implementation is probably untenable.  */
-	    {
-	      const int fd = action->action.open_action.fd;
-
-	      do_close (fd);
-	      if (fd < orig_dtablesize)
-		dtable_cloexec[fd] = 0;
-	      err = EXPAND_DTABLE (fd);
-	      if (err)
-		break;
-
-	      err = child_lookup (action->action.open_action.path,
-				  action->action.open_action.oflag,
-				  action->action.open_action.mode,
-				  &dtable[fd]);
-	      dtable_cells[fd] = NULL;
-	      break;
-	    }
-	  }
-
-	if (err)
-	  goto out;
-      }
-
-  /* Only now can we perform FD_CLOEXEC.  We had to leave the descriptors
-     unmolested for the file actions to use.  Note that the DTABLE_CLOEXEC
-     array is never expanded by file actions, so it might now have fewer
-     than DTABLESIZE elements.  */
-  for (i = 0; i < orig_dtablesize; ++i)
-    if (dtable[i] != MACH_PORT_NULL && dtable_cloexec[i])
-      {
-	assert (dtable_cells[i] != NULL);
-	_hurd_port_free (dtable_cells[i], &ulink_dtable[i], dtable[i]);
-	dtable[i] = MACH_PORT_NULL;
-      }
-
-  /* Prune trailing null ports from the descriptor table.  */
-  while (dtablesize > 0 && dtable[dtablesize - 1] == MACH_PORT_NULL)
-    --dtablesize;
-
-  if (flags & POSIX_SPAWN_RESETIDS)
-    {
-      /* Reauthenticate all the child's ports with its new auth handle.  */
-
-      mach_port_t ref;
-      process_t newproc;
-
-      /* Reauthenticate with the proc server.  */
-      ref = __mach_reply_port ();
-      err = __proc_reauthenticate (proc, ref, MACH_MSG_TYPE_MAKE_SEND);
-      if (!err)
-	err = __auth_user_authenticate (auth,
-					ref, MACH_MSG_TYPE_MAKE_SEND,
-					&newproc);
-      __mach_port_destroy (__mach_task_self (), ref);
-      if (!err)
-	{
-	  __mach_port_deallocate (__mach_task_self (), proc);
-	  proc = newproc;
-	}
-
-      if (!err)
-	err = reauthenticate (INIT_PORT_CRDIR, &rcrdir);
-      if (!err)
-	err = reauthenticate (INIT_PORT_CWDIR, &rcwdir);
-
-      /* We must reauthenticate all the fds except those that came from
-	 `spawn_do_open' file actions, which were opened using the child's
-	 auth port to begin with.  */
-      for (i = 0; !err && i < dtablesize; ++i)
-	err = reauthenticate_fd (i);
-    }
-  if (err)
-    goto out;
-
-  /* Now we are ready to open the executable file using the child's ports.
-     We do this after performing all the file actions so the order of
-     events is the same as for a fork, exec sequence.  This affects things
-     like the meaning of a /dev/fd file name, as well as which error
-     conditions are diagnosed first and what side effects (file creation,
-     etc) can be observed before what errors.  */
-
-  if ((xflags & SPAWN_XFLAGS_USE_PATH) == 0 || strchr (file, '/') != NULL)
-    /* The FILE parameter is actually a path.  */
-    err = child_lookup (file, O_EXEC, 0, &execfile);
-  else
-    {
-      /* We have to search for FILE on the path.  */
-      path = getenv ("PATH");
-      if (path == NULL)
-	{
-	  /* There is no `PATH' in the environment.
-	     The default search path is the current directory
-	     followed by the path `confstr' returns for `_CS_PATH'.  */
-	  len = confstr (_CS_PATH, (char *) NULL, 0);
-	  path = (char *) __alloca (1 + len);
-	  path[0] = ':';
-	  (void) confstr (_CS_PATH, path + 1, len);
-	}
-
-      len = strlen (file) + 1;
-      pathlen = strlen (path);
-      name = __alloca (pathlen + len + 1);
-      /* Copy the file name at the top.  */
-      name = (char *) memcpy (name + pathlen + 1, file, len);
-      /* And add the slash.  */
-      *--name = '/';
-
-      p = path;
-      do
-	{
-	  char *startp;
-
-	  path = p;
-	  p = __strchrnul (path, ':');
-
-	  if (p == path)
-	    /* Two adjacent colons, or a colon at the beginning or the end
-	       of `PATH' means to search the current directory.  */
-	    startp = name + 1;
-	  else
-	    startp = (char *) memcpy (name - (p - path), path, p - path);
-
-	  /* Try to open this file name.  */
-	  err = child_lookup (startp, O_EXEC, 0, &execfile);
-	  switch (err)
-	    {
-	    case EACCES:
-	    case ENOENT:
-	    case ESTALE:
-	    case ENOTDIR:
-	      /* Those errors indicate the file is missing or not executable
-		 by us, in which case we want to just try the next path
-		 directory.  */
-	      continue;
-
-	    case 0:		/* Success! */
-	    default:
-	      /* Some other error means we found an executable file, but
-		 something went wrong executing it; return the error to our
-		 caller.  */
-	      break;
-	    }
-
-	  // We only get here when we are done looking for the file.
-	  break;
-	}
-      while (*p++ != '\0');
-    }
-  if (err)
-    goto out;
-
-  /* Almost there!  */
-  {
-    mach_port_t ports[_hurd_nports];
-    struct hurd_userlink ulink_ports[_hurd_nports];
-    char *args = NULL, *env = NULL;
-    size_t argslen = 0, envlen = 0;
-
-    inline error_t exec (file_t file)
-      {
-	return __file_exec (file, task,
-			    (__sigismember (&_hurdsig_traced, SIGKILL)
-			     ? EXEC_SIGTRAP : 0),
-			    args, argslen, env, envlen,
-			    dtable, MACH_MSG_TYPE_COPY_SEND, dtablesize,
-			    ports, MACH_MSG_TYPE_COPY_SEND, _hurd_nports,
-			    ints, INIT_INT_MAX,
-			    NULL, 0, NULL, 0);
-      }
-
-    /* Now we are out of things that can fail before the file_exec RPC,
-       for which everything else must be prepared.  The only thing left
-       to do is packing up the argument and environment strings,
-       and the array of init ports.  */
-
-    if (argv != NULL)
-      err = __argz_create (argv, &args, &argslen);
-    if (!err && envp != NULL)
-      err = __argz_create (envp, &env, &envlen);
-
-    /* Load up the ports to give to the new program.
-       Note the loop/switch below must parallel exactly to release refs.  */
-    for (i = 0; i < _hurd_nports; ++i)
-      {
-	switch (i)
-	  {
-	  case INIT_PORT_AUTH:
-	    ports[i] = auth;
-	    continue;
-	  case INIT_PORT_PROC:
-	    ports[i] = proc;
-	    continue;
-	  case INIT_PORT_CRDIR:
-	    if (flags & POSIX_SPAWN_RESETIDS)
-	      {
-		ports[i] = rcrdir;
-		continue;
-	      }
-	    break;
-	  case INIT_PORT_CWDIR:
-	    if (flags & POSIX_SPAWN_RESETIDS)
-	      {
-		ports[i] = rcwdir;
-		continue;
-	      }
-	    break;
-	  }
-	ports[i] = _hurd_port_get (&_hurd_ports[i], &ulink_ports[i]);
-      }
-
-    /* Finally, try executing the file we opened.  */
-    if (!err)
-      err = exec (execfile);
-    __mach_port_deallocate (__mach_task_self (), execfile);
-
-    if (err == ENOEXEC)
-      {
-	/* The file is accessible but it is not an executable file.
-	   Invoke the shell to interpret it as a script.  */
-	err = __argz_insert (&args, &argslen, args, _PATH_BSHELL);
-	if (!err)
-	  err = child_lookup (_PATH_BSHELL, O_EXEC, 0, &execfile);
-	if (!err)
-	  {
-	    err = exec (execfile);
-	    __mach_port_deallocate (__mach_task_self (), execfile);
-	  }
-      }
-
-    /* Release the references just packed up in PORTS.
-       This switch must always parallel the one above that fills PORTS.  */
-    for (i = 0; i < _hurd_nports; ++i)
-      {
-	switch (i)
-	  {
-	  case INIT_PORT_AUTH:
-	  case INIT_PORT_PROC:
-	    continue;
-	  case INIT_PORT_CRDIR:
-	    if (flags & POSIX_SPAWN_RESETIDS)
-	      continue;
-	    break;
-	  case INIT_PORT_CWDIR:
-	    if (flags & POSIX_SPAWN_RESETIDS)
-	      continue;
-	    break;
-	  }
-	_hurd_port_free (&_hurd_ports[i], &ulink_ports[i], ports[i]);
-      }
-
-    free (args);
-    free (env);
-  }
-
-  /* We did it!  We have a child!  */
-  if (pid != NULL)
-    *pid = new_pid;
-
- out:
-  /* Clean up all the references we are now holding.  */
-
-  if (task != MACH_PORT_NULL)
-    {
-      if (err)
-	/* We failed after creating the task, so kill it.  */
-	__task_terminate (task);
-      __mach_port_deallocate (__mach_task_self (), task);
-    }
-  __mach_port_deallocate (__mach_task_self (), auth);
-  __mach_port_deallocate (__mach_task_self (), proc);
-  if (rcrdir != MACH_PORT_NULL)
-    __mach_port_deallocate (__mach_task_self (), rcrdir);
-  if (rcwdir != MACH_PORT_NULL)
-    __mach_port_deallocate (__mach_task_self (), rcwdir);
-
-  if (ulink_dtable)
-    /* Release references to the file descriptor ports.  */
-    for (i = 0; i < dtablesize; ++i)
-      if (dtable[i] != MACH_PORT_NULL)
-	{
-	  if (dtable_cells[i] == NULL)
-	    __mach_port_deallocate (__mach_task_self (), dtable[i]);
-	  else
-	    _hurd_port_free (dtable_cells[i], &ulink_dtable[i], dtable[i]);
-	}
-
-  if (err)
-    /* This hack canonicalizes the error code that we return.  */
-    err = (__hurd_fail (err), errno);
-
-  return err;
-}