reactos/base/shell/cmd/if.c

   1 /*
   2  *  IF.C - if internal batch command.
   3  *
   4  *
   5  *  History:
   6  *
   7  *    16 Jul 1998 (Hans B Pufal)
   8  *        started.
   9  *
  10  *    16 Jul 1998 (John P Price)
  11  *        Seperated commands into individual files.
  12  *
  13  *    27-Jul-1998 (John P Price <linux-guru@gcfl.net>)
  14  *        added config.h include
  15  *
  16  *    07-Jan-1999 (Eric Kohl)
  17  *        Added help text ("if /?") and cleaned up.
  18  *
  19  *    21-Jan-1999 (Eric Kohl)
  20  *        Unicode and redirection ready!
  21  *
  22  *    01-Sep-1999 (Eric Kohl)
  23  *        Fixed help text.
  24  *
  25  *    17-Feb-2001 (ea)
  26  *        IF DEFINED variable command
  27  *
  28  *    28-Apr-2005 (Magnus Olsen) <magnus@greatlord.com>)
  29  *        Remove all hardcode string to En.rc
  30  *
  31  */
  32
  33 #include <precomp.h>
  34
  35 static INT GenericCmp(INT (*StringCmp)(LPCTSTR, LPCTSTR),
  36                       LPCTSTR Left, LPCTSTR Right)
  37 {
  38         TCHAR *end;
  39         INT nLeft = _tcstol(Left, &end, 0);
  40         if (*end == _T('\0'))
  41         {
  42                 INT nRight = _tcstol(Right, &end, 0);
  43                 if (*end == _T('\0'))
  44                 {
  45                         /* both arguments are numeric */
  46                         return (nLeft < nRight) ? -1 : (nLeft > nRight);
  47                 }
  48         }
  49         return StringCmp(Left, Right);
  50 }
  51
  52 INT cmd_if (LPTSTR param)
  53 {
  54         TRACE ("cmd_if: (\'%s\')\n", debugstr_aw(param));
  55
  56         if (!_tcsncmp (param, _T("/?"), 2))
  57         {
  58                 ConOutResPaging(TRUE,STRING_IF_HELP1);
  59                 return 0;
  60         }
  61
  62         error_syntax(param);
  63         return 1;
  64 }
  65
  66 INT ExecuteIf(PARSED_COMMAND *Cmd)
  67 {
  68         INT result = FALSE; /* when set cause 'then' clause to be executed */
  69         LPTSTR param;
  70         LPTSTR Left = NULL, Right;
  71
  72         if (Cmd->If.LeftArg)
  73         {
  74                 Left = DoDelayedExpansion(Cmd->If.LeftArg);
  75                 if (!Left)
  76                         return 1;
  77         }
  78         Right = DoDelayedExpansion(Cmd->If.RightArg);
  79         if (!Right)
  80         {
  81                 cmd_free(Left);
  82                 return 1;
  83         }
  84
  85         if (Cmd->If.Operator == IF_CMDEXTVERSION)
  86         {
  87                 /* IF CMDEXTVERSION n: check if Command Extensions version
  88                  * is greater or equal to n */
  89                 DWORD n = _tcstoul(Right, &param, 10);
  90                 if (*param != _T('\0'))
  91                 {
  92                         error_syntax(Right);
  93                         cmd_free(Right);
  94                         return 1;
  95                 }
  96                 result = (2 >= n);
  97         }
  98         else if (Cmd->If.Operator == IF_DEFINED)
  99         {
 100                 /* IF DEFINED var: check if environment variable exists */
 101                 result = (GetEnvVarOrSpecial(Right) != NULL);
 102         }
 103         else if (Cmd->If.Operator == IF_ERRORLEVEL)
 104         {
 105                 /* IF ERRORLEVEL n: check if last exit code is greater or equal to n */
 106                 INT n = _tcstol(Right, &param, 10);
 107                 if (*param != _T('\0'))
 108                 {
 109                         error_syntax(Right);
 110                         cmd_free(Right);
 111                         return 1;
 112                 }
 113                 result = (nErrorLevel >= n);
 114         }
 115         else if (Cmd->If.Operator == IF_EXIST)
 116         {
 117                 /* IF EXIST filename: check if file exists (wildcards allowed) */
 118                 WIN32_FIND_DATA f;
 119                 HANDLE hFind;
 120
 121                 StripQuotes(Right);
 122
 123                 hFind = FindFirstFile(Right, &f);
 124                 if (hFind != INVALID_HANDLE_VALUE)
 125                 {
 126                         result = TRUE;
 127                         FindClose(hFind);
 128                 }
 129         }
 130         else
 131         {
 132                 /* Do case-insensitive string comparisons if /I specified */
 133                 INT (*StringCmp)(LPCTSTR, LPCTSTR) =
 134                         (Cmd->If.Flags & IFFLAG_IGNORECASE) ? _tcsicmp : _tcscmp;
 135
 136                 if (Cmd->If.Operator == IF_STRINGEQ)
 137                 {
 138                         /* IF str1 == str2 */
 139                         result = StringCmp(Left, Right) == 0;
 140                 }
 141                 else
 142                 {
 143                         result = GenericCmp(StringCmp, Left, Right);
 144                         switch (Cmd->If.Operator)
 145                         {
 146                         case IF_EQU: result = (result == 0); break;
 147                         case IF_NEQ: result = (result != 0); break;
 148                         case IF_LSS: result = (result < 0); break;
 149                         case IF_LEQ: result = (result <= 0); break;
 150                         case IF_GTR: result = (result > 0); break;
 151                         case IF_GEQ: result = (result >= 0); break;
 152                         }
 153                 }
 154         }
 155
 156         cmd_free(Left);
 157         cmd_free(Right);
 158
 159         if (result ^ ((Cmd->If.Flags & IFFLAG_NEGATE) != 0))
 160         {
 161                 /* full condition was true, do the command */
 162                 return ExecuteCommand(Cmd->Subcommands);
 163         }
 164         else
 165         {
 166                 /* full condition was false, do the "else" command if there is one */
 167                 if (Cmd->Subcommands->Next)
 168                         return ExecuteCommand(Cmd->Subcommands->Next);
 169                 return 0;
 170         }
 171 }
 172
 173 /* EOF */