programs/hostname/hostname.c

   1 /*
   2  * Hostname display utility
   3  *
   4  * Copyright 2008 Andrew Riedi
   5  * Copyright 2010-2011 Andrew Nguyen
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this library; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  20  */
  21
  22 #include <stdarg.h>
  23 #include <stdio.h>
  24 #include <windef.h>
  25 #include <winbase.h>
  26 #include <wincon.h>
  27 #include <winnls.h>
  28 #include <winuser.h>
  29
  30 #include "hostname.h"
  31
  32 static int hostname_vprintfW(const WCHAR *msg, va_list va_args)
  33 {
  34     int wlen;
  35     DWORD count;
  36     WCHAR msg_buffer[8192];
  37
  38     wlen = vswprintf(msg_buffer, ARRAY_SIZE(msg_buffer), msg, va_args);
  39
  40     if (!WriteConsoleW(GetStdHandle(STD_OUTPUT_HANDLE), msg_buffer, wlen, &count, NULL))
  41     {
  42         DWORD len;
  43         char *msgA;
  44
  45         /* On Windows WriteConsoleW() fails if the output is redirected. So fall
  46          * back to WriteFile() with OEM code page.
  47          */
  48         len = WideCharToMultiByte(GetOEMCP(), 0, msg_buffer, wlen,
  49             NULL, 0, NULL, NULL);
  50         msgA = HeapAlloc(GetProcessHeap(), 0, len);
  51         if (!msgA)
  52             return 0;
  53
  54         WideCharToMultiByte(GetOEMCP(), 0, msg_buffer, wlen, msgA, len, NULL, NULL);
  55         WriteFile(GetStdHandle(STD_OUTPUT_HANDLE), msgA, len, &count, FALSE);
  56         HeapFree(GetProcessHeap(), 0, msgA);
  57     }
  58
  59     return count;
  60 }
  61
  62 static int WINAPIV hostname_printfW(const WCHAR *msg, ...)
  63 {
  64     va_list va_args;
  65     int len;
  66
  67     va_start(va_args, msg);
  68     len = hostname_vprintfW(msg, va_args);
  69     va_end(va_args);
  70
  71     return len;
  72 }
  73
  74 static int WINAPIV hostname_message_printfW(int msg, ...)
  75 {
  76     va_list va_args;
  77     WCHAR msg_buffer[8192];
  78     int len;
  79
  80     LoadStringW(GetModuleHandleW(NULL), msg, msg_buffer, ARRAY_SIZE(msg_buffer));
  81
  82     va_start(va_args, msg);
  83     len = hostname_vprintfW(msg_buffer, va_args);
  84     va_end(va_args);
  85
  86     return len;
  87 }
  88
  89 static int hostname_message(int msg)
  90 {
  91     WCHAR msg_buffer[8192];
  92
  93     LoadStringW(GetModuleHandleW(NULL), msg, msg_buffer, ARRAY_SIZE(msg_buffer));
  94
  95     return hostname_printfW(L"%s", msg_buffer);
  96 }
  97
  98 static int display_computer_name(void)
  99 {
 100     WCHAR name[MAX_COMPUTERNAME_LENGTH + 1];
 101     DWORD size = ARRAY_SIZE(name);
 102     BOOL ret;
 103
 104     ret = GetComputerNameW(name, &size);
 105     if (!ret)
 106     {
 107         hostname_message_printfW(STRING_CANNOT_GET_HOSTNAME, GetLastError());
 108         return 1;
 109     }
 110
 111     hostname_printfW(L"%s\r\n", name);
 112     return 0;
 113 }
 114
 115 int __cdecl wmain(int argc, WCHAR *argv[])
 116 {
 117     if (argc > 1)
 118     {
 119         unsigned int i;
 120
 121         if (!wcsncmp(argv[1], L"/?", ARRAY_SIZE(L"/?") - 1))
 122         {
 123             hostname_message(STRING_USAGE);
 124             return 1;
 125         }
 126
 127         for (i = 1; i < argc; i++)
 128         {
 129             if (argv[i][0] == '-')
 130             {
 131                 switch (argv[i][1])
 132                 {
 133                     case 's':
 134                         /* Ignore the option and continue processing. */
 135                         break;
 136                     case '?':
 137                         hostname_message(STRING_USAGE);
 138                         return 1;
 139                     default:
 140                         hostname_message_printfW(STRING_INVALID_OPTION, argv[i][1]);
 141                         hostname_message(STRING_USAGE);
 142                         return 1;
 143                 }
 144             }
 145             else
 146             {
 147                 hostname_message(STRING_CANNOT_SET_HOSTNAME);
 148                 hostname_message(STRING_USAGE);
 149                 return 1;
 150             }
 151         }
 152     }
 153
 154     return display_computer_name();
 155 }