reactos/base/applications/cmdutils/help/help.c

   1 /*
   2  * COPYRIGHT:       See COPYING in the top level directory
   3  * PROJECT:         ReactOS help utility
   4  * FILE:            base/applications/cmdutils/help/help.c
   5  * PURPOSE:         Provide help for command-line utilities
   6  * PROGRAMMERS:     Lee Schroeder (spaceseel at gmail dot com)
   7  *                  Hermes Belusca-Maito (hermes.belusca@sfr.fr)
   8  */
   9
  10 #include <stdio.h>
  11 #include <stdlib.h>
  12 #include <wchar.h>
  13
  14 #define WIN32_NO_STATUS
  15 #include <windef.h>
  16 #include <winbase.h>
  17 #include <winuser.h>
  18 #include <wincon.h>
  19
  20 #include "help.h"
  21 #include "resource.h"
  22
  23 BOOL IsConsoleHandle(HANDLE hHandle)
  24 {
  25     DWORD dwMode;
  26
  27     /* Check whether the handle may be that of a console... */
  28     if ((GetFileType(hHandle) & FILE_TYPE_CHAR) == 0) return FALSE;
  29
  30     /*
  31      * It may be. Perform another test... The idea comes from the
  32      * MSDN description of the WriteConsole API:
  33      *
  34      * "WriteConsole fails if it is used with a standard handle
  35      *  that is redirected to a file. If an application processes
  36      *  multilingual output that can be redirected, determine whether
  37      *  the output handle is a console handle (one method is to call
  38      *  the GetConsoleMode function and check whether it succeeds).
  39      *  If the handle is a console handle, call WriteConsole. If the
  40      *  handle is not a console handle, the output is redirected and
  41      *  you should call WriteFile to perform the I/O."
  42      */
  43     return GetConsoleMode(hHandle, &dwMode);
  44 }
  45
  46 VOID PrintResourceString(INT resID, ...)
  47 {
  48     HANDLE OutputHandle = GetStdHandle(STD_OUTPUT_HANDLE);
  49     WCHAR tmpBuffer[RC_STRING_MAX_SIZE];
  50     va_list arg_ptr;
  51
  52     va_start(arg_ptr, resID);
  53     LoadStringW(GetModuleHandleW(NULL), resID, tmpBuffer, RC_STRING_MAX_SIZE);
  54
  55     // FIXME: Optimize by using Win32 console functions.
  56     if (IsConsoleHandle(OutputHandle))
  57     {
  58         _vcwprintf(tmpBuffer, arg_ptr);
  59     }
  60     else
  61     {
  62         vwprintf(tmpBuffer, arg_ptr);
  63     }
  64
  65     va_end(arg_ptr);
  66 }
  67
  68 BOOL IsInternalCommand(LPCWSTR Cmd)
  69 {
  70     size_t i;
  71     int res;
  72
  73     /* Invalid command */
  74     if (!Cmd) return FALSE;
  75
  76     for (i = 0; i < sizeof(InternalCommands)/sizeof(InternalCommands[0]); ++i)
  77     {
  78         res = _wcsicmp(InternalCommands[i], Cmd);
  79         if (res == 0)
  80         {
  81             /* This is an internal command */
  82             return TRUE;
  83         }
  84         else if (res > 0)
  85         {
  86             /*
  87              * The internal commands list is sorted in alphabetical order.
  88              * We can quit the loop immediately since the current internal
  89              * command is lexically greater than the command to be tested.
  90              */
  91             break;
  92         }
  93     }
  94
  95     /* Command not found */
  96     return FALSE;
  97 }
  98
  99 int wmain(int argc, WCHAR* argv[])
 100 {
 101     WCHAR CmdLine[CMDLINE_LENGTH];
 102
 103     /*
 104      * If the user hasn't asked for specific help,
 105      * then print out the list of available commands.
 106      */
 107     if (argc <= 1)
 108     {
 109         PrintResourceString(IDS_HELP1);
 110         PrintResourceString(IDS_HELP2);
 111         return 0;
 112     }
 113
 114     /*
 115      * Bad usage (too much options) or we use the /? switch.
 116      * Display help for the help command.
 117      */
 118     if ((argc > 2) || (wcscmp(argv[1], L"/?") == 0))
 119     {
 120         PrintResourceString(IDS_USAGE);
 121         return 0;
 122     }
 123
 124     /*
 125      * If the command is not an internal one,
 126      * display an information message and exit.
 127      */
 128     if (!IsInternalCommand(argv[1]))
 129     {
 130         PrintResourceString(IDS_NO_ENTRY, argv[1]);
 131         return 0;
 132     }
 133
 134     /*
 135      * Run "<command> /?" in the current command processor.
 136      */
 137     wcsncpy(CmdLine, argv[1], CMDLINE_LENGTH - wcslen(CmdLine));
 138     wcsncat(CmdLine, L" /?" , CMDLINE_LENGTH - wcslen(CmdLine));
 139
 140     _flushall();
 141     return _wsystem(CmdLine);
 142 }
 143
 144 /* EOF */