base/shell/cmd/setlocal.c

   1 /*
   2  *  SETLOCAL.C - setlocal and endlocal internal batch commands.
   3  *
   4  *  History:
   5  *
   6  *    1 Feb 2008 (Christoph von Wittich)
   7  *        started.
   8 */
   9
  10 #include "precomp.h"
  11
  12 typedef struct _SETLOCAL {
  13         struct _SETLOCAL *Prev;
  14         BOOL DelayedExpansion;
  15         LPTSTR Environment;
  16 } SETLOCAL;
  17
  18 /* Create a copy of the current environment */
  19 LPTSTR
  20 DuplicateEnvironment(VOID)
  21 {
  22         LPTSTR Environ = GetEnvironmentStrings();
  23         LPTSTR End, EnvironCopy;
  24         if (!Environ)
  25                 return NULL;
  26         for (End = Environ; *End; End += _tcslen(End) + 1)
  27                 ;
  28         EnvironCopy = cmd_alloc((End + 1 - Environ) * sizeof(TCHAR));
  29         if (EnvironCopy)
  30                 memcpy(EnvironCopy, Environ, (End + 1 - Environ) * sizeof(TCHAR));
  31         FreeEnvironmentStrings(Environ);
  32         return EnvironCopy;
  33 }
  34
  35 INT cmd_setlocal(LPTSTR param)
  36 {
  37         SETLOCAL *Saved;
  38         LPTSTR *arg;
  39         INT argc, i;
  40
  41         /* SETLOCAL only works inside a batch file */
  42         if (!bc)
  43                 return 0;
  44
  45         Saved = cmd_alloc(sizeof(SETLOCAL));
  46         if (!Saved)
  47         {
  48                 error_out_of_memory();
  49                 return 1;
  50         }
  51         Saved->Prev = bc->setlocal;
  52         Saved->DelayedExpansion = bDelayedExpansion;
  53         Saved->Environment = DuplicateEnvironment();
  54         if (!Saved->Environment)
  55         {
  56                 error_out_of_memory();
  57                 cmd_free(Saved);
  58                 return 1;
  59         }
  60         bc->setlocal = Saved;
  61
  62         nErrorLevel = 0;
  63
  64         arg = splitspace(param, &argc);
  65         for (i = 0; i < argc; i++)
  66         {
  67                 if (!_tcsicmp(arg[i], _T("enableextensions")))
  68                         /* not implemented, ignore */;
  69                 else if (!_tcsicmp(arg[i], _T("disableextensions")))
  70                         /* not implemented, ignore */;
  71                 else if (!_tcsicmp(arg[i], _T("enabledelayedexpansion")))
  72                         bDelayedExpansion = TRUE;
  73                 else if (!_tcsicmp(arg[i], _T("disabledelayedexpansion")))
  74                         bDelayedExpansion = FALSE;
  75                 else
  76                 {
  77                         error_invalid_parameter_format(arg[i]);
  78                         break;
  79                 }
  80         }
  81         freep(arg);
  82
  83         return nErrorLevel;
  84 }
  85
  86 /* endlocal doesn't take any params */
  87 INT cmd_endlocal(LPTSTR param)
  88 {
  89         LPTSTR Environ, Name, Value;
  90         SETLOCAL *Saved;
  91
  92         /* Pop a SETLOCAL struct off of this batch file's stack */
  93         if (!bc || !(Saved = bc->setlocal))
  94                 return 0;
  95         bc->setlocal = Saved->Prev;
  96
  97         bDelayedExpansion = Saved->DelayedExpansion;
  98
  99         /* First, clear out the environment. Since making any changes to the
 100          * environment invalidates pointers obtained from GetEnvironmentStrings(),
 101          * we must make a copy of it and get the variable names from that */
 102         Environ = DuplicateEnvironment();
 103         if (Environ)
 104         {
 105                 for (Name = Environ; *Name; Name += _tcslen(Name) + 1)
 106                 {
 107                         if (!(Value = _tcschr(Name + 1, _T('='))))
 108                                 continue;
 109                         *Value++ = _T('\0');
 110                         SetEnvironmentVariable(Name, NULL);
 111                         Name = Value;
 112                 }
 113                 cmd_free(Environ);
 114         }
 115
 116         /* Now, restore variables from the copy saved by cmd_setlocal */
 117         for (Name = Saved->Environment; *Name; Name += _tcslen(Name) + 1)
 118         {
 119                 if (!(Value = _tcschr(Name + 1, _T('='))))
 120                         continue;
 121                 *Value++ = _T('\0');
 122                 SetEnvironmentVariable(Name, Value);
 123                 Name = Value;
 124         }
 125
 126         cmd_free(Saved->Environment);
 127         cmd_free(Saved);
 128         return 0;
 129 }