view lib/spawn_int.h @ 15988:cd7ac59d8eb5

fts: close parent dir FD before returning from post-traversal fts_read The problem: the fts-using "mkdir -p A/B; rm -rf A" would attempt to unlink A, even though an FD open on A remained. This is suboptimal (holding a file descriptor open longer than needed), but otherwise not a problem on Unix-like kernels. However, on Cygwin with certain Novell file systems, (see http://cygwin.com/ml/cygwin/2011-10/msg00365.html), that represents a real problem: it causes the removal of A to fail with e.g., "rm: cannot remove `A': Device or resource busy" fts visits each directory twice and keeps a cache (fts_fd_ring) of directory file descriptors. After completing the final, FTS_DP, visit of a directory, RESTORE_INITIAL_CWD intended to clear the FD cache, but then proceeded to add a new FD to it via the subsequent FCHDIR (which calls cwd_advance_fd and i_ring_push). Before, the final file descriptor would be closed only via fts_close's call to fd_ring_clear. Now, it is usually closed earlier, via the final FTS_DP-returning fts_read call. * lib/fts.c (restore_initial_cwd): New function, converted from the macro. Call fd_ring_clear *after* FCHDIR, not before it. Update callers. Reported by Franz Sirl via the above URL, with analysis by Eric Blake in http://thread.gmane.org/gmane.comp.lib.gnulib.bugs/28739
author Jim Meyering <meyering@redhat.com>
date Sun, 23 Oct 2011 22:42:25 +0200
parents 97fc9a21a8fb
children 8250f2777afc
line wrap: on
line source

/* Copyright (C) 2000, 2008-2011 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   This program is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program 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 General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

#include <sys/types.h>

/* Data structure to contain the action information.  */
struct __spawn_action
{
  enum
  {
    spawn_do_close,
    spawn_do_dup2,
    spawn_do_open
  } tag;

  union
  {
    struct
    {
      int fd;
    } close_action;
    struct
    {
      int fd;
      int newfd;
    } dup2_action;
    struct
    {
      int fd;
      const char *path;
      int oflag;
      mode_t mode;
    } open_action;
  } action;
};

#if !_LIBC
# define __posix_spawn_file_actions_realloc gl_posix_spawn_file_actions_realloc
#endif
extern int __posix_spawn_file_actions_realloc (posix_spawn_file_actions_t *
                                               file_actions);

#if !_LIBC
# define __spawni gl_posix_spawn_internal
#endif
extern int __spawni (pid_t *pid, const char *path,
                     const posix_spawn_file_actions_t *file_actions,
                     const posix_spawnattr_t *attrp, char *const argv[],
                     char *const envp[], int use_path);