string/argz-create.c

   1 /* Routines for dealing with '\0' separated arg vectors.
   2    Copyright (C) 1995-2019 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Written by Miles Bader <miles@gnu.ai.mit.edu>
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, see
  18    <https://www.gnu.org/licenses/>.  */
  19
  20 #include <argz.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23
  24 /* Make a '\0' separated arg vector from a unix argv vector, returning it in
  25    ARGZ, and the total length in LEN.  If a memory allocation error occurs,
  26    ENOMEM is returned, otherwise 0.  */
  27 error_t
  28 __argz_create (char *const argv[], char **argz, size_t *len)
  29 {
  30   int argc;
  31   size_t tlen = 0;
  32   char *const *ap;
  33   char *p;
  34
  35   for (argc = 0; argv[argc] != NULL; ++argc)
  36     tlen += strlen (argv[argc]) + 1;
  37
  38   if (tlen == 0)
  39     *argz = NULL;
  40   else
  41     {
  42       *argz = malloc (tlen);
  43       if (*argz == NULL)
  44         return ENOMEM;
  45
  46       for (p = *argz, ap = argv; *ap; ++ap, ++p)
  47         p = __stpcpy (p, *ap);
  48     }
  49   *len = tlen;
  50
  51   return 0;
  52 }
  53 weak_alias (__argz_create, argz_create)