LXR toybox/toys/lsb/hostname.c

   1/* hostname.c - Get/Set the hostname
   2 *
   3 * Copyright 2012 Andre Renaud <andre@bluewatersys.com>
   4 *
   5 * http://refspecs.linuxfoundation.org/LSB_4.1.0/LSB-Core-generic/LSB-Core-generic/hostname.html
   6
   7USE_HOSTNAME(NEWTOY(hostname, ">1bdsfF:[!bdsf]", TOYFLAG_BIN))
   8USE_DNSDOMAINNAME(NEWTOY(dnsdomainname, ">0", TOYFLAG_BIN))
   9
  10config HOSTNAME
  11  bool "hostname"
  12  default y
  13  help
  14    usage: hostname [-bdsf] [-F FILENAME] [newname]
  15
  16    Get/set the current hostname.
  17
  18    -b  Set hostname to 'localhost' if otherwise unset
  19    -d  Show DNS domain name (no host)
  20    -f  Show fully-qualified name (host+domain, FQDN)
  21    -F  Set hostname to contents of FILENAME
  22    -s  Show short host name (no domain)
  23
  24config DNSDOMAINNAME
  25  bool "dnsdomainname"
  26  default y
  27  help
  28    usage: dnsdomainname
  29
  30    Show domain this system belongs to (same as hostname -d).
  31*/
  32
  33#define FOR_hostname
  34#define FORCE_FLAGS
  35#include "toys.h"
  36
  37GLOBALS(
  38  char *F;
  39)
  40
  41void hostname_main(void)
  42{
  43  char *hostname = toybuf, *dot;
  44  struct hostent *h;
  45
  46  gethostname(toybuf, sizeof(toybuf)-1);
  47  if (TT.F && (hostname = xreadfile(TT.F, 0, 0))) {
  48    if (!*chomp(hostname)) {
  49      if (CFG_TOYBOX_FREE) free(hostname);
  50      if (!FLAG(b)) error_exit("empty '%s'", TT.F);
  51      hostname = 0;
  52    }
  53  } else hostname  = (FLAG(b) && !*toybuf) ? "localhost" : *toys.optargs;
  54
  55  // Setting?
  56  if (hostname) {
  57    if (sethostname(hostname, strlen(hostname)))
  58      perror_exit("set '%s'", hostname);
  59    return;
  60  }
  61
  62  // We only do the DNS lookup for -d and -f.
  63  if (FLAG(d) || FLAG(f)) {
  64    if (!(h = gethostbyname(toybuf)))
  65      error_exit("gethostbyname: %s", hstrerror(h_errno));
  66    snprintf(toybuf, sizeof(toybuf), "%s", h->h_name);
  67  }
  68  dot = toybuf+strcspn(toybuf, ".");
  69  if (FLAG(s)) *dot = '\0';
  70  xputs(FLAG(d) ? dot+1 : toybuf);
  71}
  72
  73void dnsdomainname_main(void)
  74{
  75  toys.optflags = FLAG_d;
  76  hostname_main();
  77}
  78