posix/spawn_faction_addopen.c

   1 /* Copyright (C) 2000 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, write to the Free
  16    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  17    02111-1307 USA.  */
  18
  19 #include <errno.h>
  20 #include <spawn.h>
  21 #include <unistd.h>
  22
  23 #include "spawn_int.h"
  24
  25 /* Add an action to FILE-ACTIONS which tells the implementation to call
  26    `open' for the given file during the `spawn' call.  */
  27 int
  28 posix_spawn_file_actions_addopen (posix_spawn_file_actions_t *file_actions,
  29                                   int fd, const char *path, int oflag,
  30                                   mode_t mode)
  31 {
  32   int maxfd = __sysconf (_SC_OPEN_MAX);
  33   struct __spawn_action *rec;
  34
  35   /* Test for the validity of the file descriptor.  */
  36   if (fd < 0 || fd >= maxfd)
  37     return EBADF;
  38
  39   /* Allocate more memory if needed.  */
  40   if (file_actions->__used == file_actions->__allocated
  41       && __posix_spawn_file_actions_realloc (file_actions) != 0)
  42     /* This can only mean we ran out of memory.  */
  43     return ENOMEM;
  44
  45   /* Add the new value.  */
  46   rec = &file_actions->__actions[file_actions->__used];
  47   rec->tag = spawn_do_open;
  48   rec->action.open_action.fd = fd;
  49   rec->action.open_action.path = path;
  50   rec->action.open_action.oflag = oflag;
  51   rec->action.open_action.mode = mode;
  52
  53   /* Account for the new entry.  */
  54   ++file_actions->__used;
  55
  56   return 0;
  57 }