putenv.c

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Hash : 26fd3545
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Date : 2025-09-16T23:08:01

stringeq: prefer streq to strcmp in other modules

* lib/acl-internal.c, lib/argmatch.c, lib/argp-help.c:
* lib/argp-parse.c, lib/bcp47.c, lib/c32_get_mapping.c:
* lib/c32_get_type_test.c, lib/concat-filename.c:
* lib/cpu-supports.h, lib/dfa.c, lib/duplocale.c, lib/exclude.c:
* lib/findprog-in.c, lib/findprog.c, lib/fopen.c, lib/freopen.c:
* lib/fts.c, lib/gen-uni-tables.c, lib/getfilecon.c:
* lib/getlogin.c, lib/getugroups.c, lib/hard-locale.c:
* lib/hashcode-named-file.c, lib/hashkey-string.c:
* lib/iconv_open.c, lib/idcache.c, lib/lc-charset-unicode.c:
* lib/localcharset.c, lib/localename-environ.c:
* lib/localename-unsafe.c, lib/mbs_endswith.c, lib/mountlist.c:
* lib/newlocale.c, lib/nl_langinfo.c, lib/nproc.c, lib/open.c:
* lib/os2-spawn.c, lib/parse-datetime.y, lib/popen.c:
* lib/progreloc.c, lib/propername.c, lib/pt_chown.c, lib/putenv.c:
* lib/qcopy-acl.c, lib/readutmp.c, lib/rpmatch.c:
* lib/setlocale-fixes.c, lib/setlocale.c, lib/sig2str.c:
* lib/spawni.c, lib/stat.c, lib/str_endswith.c, lib/streq.h:
* lib/striconveha.c, lib/struniq.h, lib/supersede.c:
* lib/time_rz.c, lib/unicodeio.c, lib/vasnprintf.c:
* lib/vc-mtime.c, lib/wctrans-impl.h, lib/wctype-impl.h:
Prefer streq to strcmp when either will do.
Do not make this change to files shared with glibc.
Do not make the change to test files, at least not for now.
* lib/gen-uni-tables.c (streq): New static function, in same style.
* modules/acl-permissions, modules/argp, modules/c32_get_mapping:
* modules/c32_get_type_test, modules/concat-filename:
* modules/cpu-supports, modules/dfa, modules/duplocale:
* modules/exclude, modules/findprog, modules/findprog-in:
* modules/fopen, modules/fopen-gnu, modules/freopen, modules/fts:
* modules/getlocalename_l-simple, modules/getlocalename_l-unsafe:
* modules/getlogin, modules/getugroups, modules/hard-locale:
* modules/hashcode-named-file, modules/hashkey-string:
* modules/iconv_open, modules/idcache, modules/localcharset:
* modules/localename, modules/localename-unsafe:
* modules/mbs_endswith, modules/mountlist, modules/newlocale:
* modules/nl_langinfo, modules/nproc, modules/open:
* modules/parse-datetime, modules/popen:
* modules/posix_spawn-internal, modules/propername:
* modules/pt_chown, modules/putenv-gnu, modules/qcopy-acl:
* modules/rpmatch, modules/selinux-h, modules/setenv:
* modules/setlocale, modules/setlocale-fixes, modules/sig2str:
* modules/spawn-pipe, modules/stat, modules/str_endswith:
* modules/streq, modules/striconveha, modules/supersede:
* modules/time_rz, modules/uchar-h, modules/unicodeio:
* modules/uniconv/base, modules/wctrans, modules/wctype:
(Depends-on): Add stringeq.

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lib/putenv.c

/* Copyright (C) 1991, 1994, 1997-1998, 2000, 2003-2025 Free Software
   Foundation, Inc.

   NOTE: The canonical source of this file is maintained with the GNU C
   Library.  Bugs can be reported to bug-glibc@prep.ai.mit.edu.

   This file is free software: you can redistribute it and/or modify
   it under the terms of the GNU Lesser General Public License as
   published by the Free Software Foundation, either version 3 of the
   License, or (at your option) any later version.

   This file is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public License
   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */

#include <config.h>

/* Specification.  */
#include <stdlib.h>

#include <stddef.h>

/* Include errno.h *after* sys/types.h to work around header problems
   on AIX 3.2.5.  */
#include <errno.h>
#ifndef __set_errno
# define __set_errno(ev) ((errno) = (ev))
#endif

#include <string.h>
#include <unistd.h>

#if defined _WIN32 && ! defined __CYGWIN__
# define WIN32_LEAN_AND_MEAN
# include <windows.h>
#endif

#if _LIBC
# if HAVE_GNU_LD
#  define environ __environ
# else
extern char **environ;
# endif
#endif

#if _LIBC
/* This lock protects against simultaneous modifications of 'environ'.  */
# include <bits/libc-lock.h>
__libc_lock_define_initialized (static, envlock)
# define LOCK   __libc_lock_lock (envlock)
# define UNLOCK __libc_lock_unlock (envlock)
#else
# define LOCK
# define UNLOCK
#endif

#if defined _WIN32 && ! defined __CYGWIN__
/* Don't assume that UNICODE is not defined.  */
# undef SetEnvironmentVariable
# define SetEnvironmentVariable SetEnvironmentVariableA
#endif

/* Put STRING, which is of the form "NAME=VALUE", in the environment.
   If STRING contains no '=', then remove STRING from the environment.  */
int
putenv (char *string)
{
  const char *name_end = strchr (string, '=');
  char **ep;

  if (name_end == NULL)
    {
      /* Remove the variable from the environment.  */
      return unsetenv (string);
    }

#if HAVE_DECL__PUTENV /* native Windows */
  /* The Microsoft documentation
     <https://learn.microsoft.com/en-us/cpp/c-runtime-library/reference/putenv-wputenv>
     says:
       "Don't change an environment entry directly: instead,
        use _putenv or _wputenv to change it."
     Note: Microsoft's _putenv updates not only the contents of _environ but
     also the contents of _wenviron, so that both are in kept in sync.

     If we didn't follow this advice, our code and other parts of the
     application (that use _putenv) would fight over who owns the environ vector
     and thus cause a crash.  */
  if (name_end[1])
    return _putenv (string);
  else
    {
      /* _putenv ("NAME=") unsets NAME, so invoke _putenv ("NAME= ")
         to allocate the environ vector and then replace the new
         entry with "NAME=".  */
      int putenv_result;
      char *name_x = malloc (name_end - string + sizeof "= ");
      if (!name_x)
        return -1;
      memcpy (name_x, string, name_end - string + 1);
      name_x[name_end - string + 1] = ' ';
      name_x[name_end - string + 2] = 0;
      putenv_result = _putenv (name_x);
      for (ep = environ; *ep; ep++)
        if (streq (*ep, name_x))
          {
            *ep = string;
            break;
          }
# if defined _WIN32 && ! defined __CYGWIN__
      if (putenv_result == 0)
        {
          /* _putenv propagated "NAME= " into the subprocess environment;
             fix that by calling SetEnvironmentVariable directly.  */
          name_x[name_end - string] = 0;
          putenv_result = SetEnvironmentVariable (name_x, "") ? 0 : -1;
          errno = ENOMEM; /* ENOMEM is the only way to fail.  */
        }
# endif
      free (name_x);
      return putenv_result;
    }
#else
  for (ep = environ; *ep; ep++)
    if (strncmp (*ep, string, name_end - string) == 0
        && (*ep)[name_end - string] == '=')
      break;

  if (*ep)
    *ep = string;
  else
    {
      static char **last_environ = NULL;
      size_t size = ep - environ;
      char **new_environ = malloc ((size + 2) * sizeof *new_environ);
      if (! new_environ)
        return -1;
      new_environ[0] = string;
      memcpy (new_environ + 1, environ, (size + 1) * sizeof *new_environ);
      free (last_environ);
      last_environ = new_environ;
      environ = new_environ;
    }

  return 0;
#endif
}

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kc3-lang/gnulib/lib/putenv.c

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lib/putenv.c