lib/getlogin.c

   1 /* Provide a working getlogin for systems which lack it.
   2
   3    Copyright (C) 2010-2024 Free Software Foundation, Inc.
   4
   5    This file is free software: you can redistribute it and/or modify
   6    it under the terms of the GNU Lesser General Public License as
   7    published by the Free Software Foundation; either version 2.1 of the
   8    License, or (at your option) any later version.
   9
  10    This file 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
  13    GNU Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public License
  16    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  17
  18 /* Written by Bruno Haible, 2010.  */
  19
  20 #include <config.h>
  21
  22 /* Specification.  */
  23 #include <unistd.h>
  24
  25 #if defined _WIN32 && ! defined __CYGWIN__
  26 # define WIN32_LEAN_AND_MEAN
  27 # include <windows.h>
  28 /* Don't assume that UNICODE is not defined.  */
  29 # undef GetUserName
  30 # define GetUserName GetUserNameA
  31 #endif
  32
  33 char *
  34 getlogin (void)
  35 {
  36 #if defined _WIN32 && ! defined __CYGWIN__
  37   static char login_name[1024];
  38   DWORD sz = sizeof (login_name);
  39
  40   if (GetUserName (login_name, &sz))
  41     return login_name;
  42 #endif
  43   return NULL;
  44 }