1  /* Copyright (C) 1992-2023 Free Software Foundation, Inc.
       2     This file is part of the GNU C Library.
       3  
       4     The GNU C Library is free software; you can redistribute it and/or
       5     modify it under the terms of the GNU Lesser General Public
       6     License as published by the Free Software Foundation; either
       7     version 2.1 of the License, or (at your option) any later version.
       8  
       9     The GNU C Library is distributed in the hope that it will be useful,
      10     but WITHOUT ANY WARRANTY; without even the implied warranty of
      11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      12     Lesser General Public License for more details.
      13  
      14     You should have received a copy of the GNU Lesser General Public
      15     License along with the GNU C Library; if not, see
      16     <https://www.gnu.org/licenses/>.  */
      17  
      18  #include <errno.h>
      19  #include <string.h>
      20  #include <unistd.h>
      21  #include <sys/utsname.h>
      22  
      23  /* Put the name of the current host in no more than LEN bytes of NAME.
      24     The result is null-terminated if LEN is large enough for the full
      25     name and the terminator.  */
      26  int
      27  __gethostname (char *name, size_t len)
      28  {
      29    struct utsname buf;
      30    size_t node_len;
      31  
      32    if (__uname (&buf))
      33      return -1;
      34  
      35    node_len = strlen (buf.nodename) + 1;
      36    memcpy (name, buf.nodename, len < node_len ? len : node_len);
      37  
      38    if (node_len > len)
      39      {
      40        __set_errno (ENAMETOOLONG);
      41        return -1;
      42      }
      43    return 0;
      44  }
      45  
      46  weak_alias (__gethostname, gethostname)