string/envz.h

   1 /* Routines for dealing with '\0' separated environment vectors
   2    Copyright (C) 1995, 96, 98, 99, 2000 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the 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    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    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 (__const char *__restrict __envz, size_t __envz_len,
  35                          __const char *__restrict __name)
  36      __THROW __attribute_pure__;
  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 (__const char *__restrict __envz, size_t __envz_len,
  41                        __const char *__restrict __name)
  42      __THROW __attribute_pure__;
  43
  44 /* Adds an entry for NAME with value VALUE to ENVZ & ENVZ_LEN.  If an entry
  45    with the same name already exists in ENVZ, it is removed.  If VALUE is
  46    NULL, then the new entry will a special null one, for which envz_get will
  47    return NULL, although envz_entry will still return an entry; this is handy
  48    because when merging with another envz, the null entry can override an
  49    entry in the other one.  Null entries can be removed with envz_strip ().  */
  50 extern error_t envz_add (char **__restrict __envz,
  51                          size_t *__restrict __envz_len,
  52                          __const char *__restrict __name,
  53                          __const char *__restrict __value) __THROW;
  54
  55 /* Adds each entry in ENVZ2 to ENVZ & ENVZ_LEN, as if with envz_add().  If
  56    OVERRIDE is true, then values in ENVZ2 will supersede those with the same
  57    name in ENV, otherwise not.  */
  58 extern error_t envz_merge (char **__restrict __envz,
  59                            size_t *__restrict __envz_len,
  60                            __const char *__restrict __envz2,
  61                            size_t __envz2_len, int __override) __THROW;
  62
  63 /* Remove the entry for NAME from ENVZ & ENVZ_LEN, if any.  */
  64 extern void envz_remove (char **__restrict __envz,
  65                          size_t *__restrict __envz_len,
  66                          __const char *__restrict __name) __THROW;
  67
  68 /* Remove null entries.  */
  69 extern void envz_strip (char **__restrict __envz,
  70                         size_t *__restrict __envz_len) __THROW;
  71
  72 __END_DECLS
  73
  74 #endif /* envz.h */