string/envz.h

   1 /* Routines for dealing with '\0' separated environment vectors
   2    Copyright (C) 1995, 1996, 1998 Free Software Foundation, Inc.
   3    Written by Miles Bader <miles@gnu.ai.mit.edu>
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Library General Public License as
   7    published by the Free Software Foundation; either version 2 of the
   8    License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Library General Public License for more details.
  14
  15    You should have received a copy of the GNU Library General Public
  16    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  17    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  18    Boston, MA 02111-1307, USA.  */
  19
  20 #ifndef _ENVZ_H
  21 #define _ENVZ_H 1
  22
  23 #include <features.h>
  24
  25 #include <errno.h>
  26
  27 /* Envz's are argz's too, and should be created etc., using the same
  28    routines.  */
  29 #include <argz.h>
  30
  31 __BEGIN_DECLS
  32
  33 /* Returns a pointer to the entry in ENVZ for NAME, or 0 if there is none.  */
  34 extern char *envz_entry __P ((__const char *__restrict __envz,
  35                               size_t __envz_len,
  36                               __const char *__restrict __name));
  37
  38 /* Returns a pointer to the value portion of the entry in ENVZ for NAME, or 0
  39    if there is none.  */
  40 extern char *envz_get __P ((__const char *__restrict __envz, size_t __envz_len,
  41                             __const char *__restrict __name));
  42
  43 /* Adds an entry for NAME with value VALUE to ENVZ & ENVZ_LEN.  If an entry
  44    with the same name already exists in ENVZ, it is removed.  If VALUE is
  45    NULL, then the new entry will a special null one, for which envz_get will
  46    return NULL, although envz_entry will still return an entry; this is handy
  47    because when merging with another envz, the null entry can override an
  48    entry in the other one.  Null entries can be removed with envz_strip ().  */
  49 extern error_t envz_add __P ((char **__restrict __envz,
  50                               size_t *__restrict __envz_len,
  51                               __const char *__restrict __name,
  52                               __const char *__restrict __value));
  53
  54 /* Adds each entry in ENVZ2 to ENVZ & ENVZ_LEN, as if with envz_add().  If
  55    OVERRIDE is true, then values in ENVZ2 will supersede those with the same
  56    name in ENV, otherwise not.  */
  57 extern error_t envz_merge __P ((char **__restrict __envz,
  58                                 size_t *__restrict __envz_len,
  59                                 __const char *__restrict __envz2,
  60                                 size_t __envz2_len, int __override));
  61
  62 /* Remove the entry for NAME from ENVZ & ENVZ_LEN, if any.  */
  63 extern void envz_remove __P ((char **__restrict __envz,
  64                               size_t *__restrict __envz_len,
  65                               __const char *__restrict __name));
  66
  67 /* Remove null entries.  */
  68 extern void envz_strip __P ((char **__restrict __envz,
  69                              size_t *__restrict __envz_len));
  70
  71 __END_DECLS
  72
  73 #endif /* envz.h */