45 lines
1.3 KiB
C
45 lines
1.3 KiB
C
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/* -*-comment-start: "//";comment-end:""-*-
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* GNU Mes --- Maxwell Equations of Software
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* Copyright © 2016,2017,2018 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
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*
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* This file is part of GNU Mes.
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*
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* GNU Mes is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 3 of the License, or (at
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* your option) any later version.
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*
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* GNU Mes is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with GNU Mes. If not, see <http://www.gnu.org/licenses/>.
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*/
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#include <stdlib.h>
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int
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setenv (char const* s, char const* v, int overwrite_p)
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{
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char **p = environ;
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int length = strlen (s);
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while (*p)
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{
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if (!strncmp (s, *p, length) && *(*p + length) == '=')
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break;
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p++;
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}
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char *entry = malloc (length + strlen (v) + 2);
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int end_p = *p == 0;
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*p = entry;
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strcpy (entry, s);
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strcpy (entry + length, "=");
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strcpy (entry + length + 1, v);
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*(entry + length + strlen (v) + 2) = 0;
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if (end_p)
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*++p = 0;
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return 0;
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}
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