Make delayed environment-variable expansions actually be delayed.

svn path=/trunk/; revision=39597

reactos/base/shell/cmd/cmd.c

@@ -868,6 +868,7 @@ ExecuteCommand(PARSED_COMMAND *Cmd)
 {
 	BOOL bNewBatch = TRUE;
 	PARSED_COMMAND *Sub;
+	LPTSTR ExpandedLine;
 	BOOL Success = TRUE;
 
 	if (!PerformRedirection(Cmd->Redirections))
@@ -879,7 +880,14 @@ ExecuteCommand(PARSED_COMMAND *Cmd)
 		if(bc)
 			bNewBatch = FALSE;
 
-		Success = DoCommand(Cmd->Command.CommandLine);
+		ExpandedLine = DoDelayedExpansion(Cmd->Command.CommandLine);
+		if (!ExpandedLine)
+		{
+			Success = FALSE;
+			break;
+		}
+		Success = DoCommand(ExpandedLine);
+		cmd_free(ExpandedLine);
 
 		if(bNewBatch && bc)
 			AddBatchRedirection(&Cmd->Redirections);
@@ -1097,8 +1105,11 @@ GetBatchVar ( LPCTSTR varName, UINT* varNameLen )
 	return NULL;
 }
 
+BOOL bNoInteractive;
+BOOL bIsBatch;
+
 BOOL
-SubstituteVars(TCHAR *Src, TCHAR *Dest, TCHAR Delim, BOOL bIsBatch)
+SubstituteVars(TCHAR *Src, TCHAR *Dest, TCHAR Delim)
 {
 #define APPEND(From, Length) { \
 	if (Dest + (Length) > DestEnd) \
@@ -1250,15 +1261,27 @@ too_long:
 #undef APPEND1
 }
 
+LPTSTR
+DoDelayedExpansion(LPTSTR Line)
+{
+	TCHAR Buf[CMDLINE_LENGTH];
+	if (!_tcschr(Line, _T('!')))
+		return cmd_dup(Line);
+
+	/* FIXME: Delayed substitutions actually aren't quite the same as
+	 * immediate substitutions. In particular, it's possible to escape
+	 * the exclamation point using ^. */
+	if (!SubstituteVars(Line, Buf, _T('!')))
+		return NULL;
+	return cmd_dup(Buf);
+}
+
 
 /*
  * do the prompt/input/process loop
  *
  */
 
-BOOL bNoInteractive;
-BOOL bIsBatch;
-
 BOOL
 ReadLine (TCHAR *commandline, BOOL bMore)
 {
@@ -1299,15 +1322,7 @@ ReadLine (TCHAR *commandline, BOOL bMore)
 		bIsBatch = TRUE;
 	}
 
-	if (!SubstituteVars(ip, commandline, _T('%'), bIsBatch))
-		return FALSE;
-
-	/* FIXME: !vars! should be substituted later, after parsing. */
-	if (!SubstituteVars(commandline, readline, _T('!'), bIsBatch))
-		return FALSE;
-	_tcscpy(commandline, readline);
-
-	return TRUE;
+	return SubstituteVars(ip, commandline, _T('%'));
 }
 
 static INT

reactos/base/shell/cmd/cmd.h

@@ -102,6 +102,7 @@ BOOL ExecuteCommand(struct _PARSED_COMMAND *Cmd);
 LPCTSTR GetEnvVarOrSpecial ( LPCTSTR varName );
 VOID AddBreakHandler (VOID);
 VOID RemoveBreakHandler (VOID);
+LPTSTR DoDelayedExpansion(LPTSTR Line);
 BOOL DoCommand (LPTSTR line);
 BOOL ReadLine(TCHAR *commandline, BOOL bMore);
 int cmd_main (int argc, const TCHAR *argv[]);

reactos/base/shell/cmd/if.c

@@ -67,15 +67,30 @@ BOOL ExecuteIf(PARSED_COMMAND *Cmd)
 {
 	INT result = FALSE; /* when set cause 'then' clause to be executed */
 	LPTSTR param;
+	LPTSTR Left = NULL, Right;
+
+	if (Cmd->If.LeftArg)
+	{
+		Left = DoDelayedExpansion(Cmd->If.LeftArg);
+		if (!Left)
+			return FALSE;
+	}
+	Right = DoDelayedExpansion(Cmd->If.RightArg);
+	if (!Right)
+	{
+		cmd_free(Left);
+		return FALSE;
+	}
 
 	if (Cmd->If.Operator == IF_CMDEXTVERSION)
 	{
 		/* IF CMDEXTVERSION n: check if Command Extensions version
 		 * is greater or equal to n */
-		DWORD n = _tcstoul(Cmd->If.RightArg, &param, 10);
+		DWORD n = _tcstoul(Right, &param, 10);
 		if (*param != _T('\0'))
 		{
-			error_syntax(Cmd->If.RightArg);
+			error_syntax(Right);
+			cmd_free(Right);
 			return FALSE;
 		}
 		result = (2 >= n);
@@ -83,7 +98,7 @@ BOOL ExecuteIf(PARSED_COMMAND *Cmd)
 	else if (Cmd->If.Operator == IF_DEFINED)
 	{
 		/* IF DEFINED var: check if environment variable exists */
-		result = (GetEnvVarOrSpecial(Cmd->If.RightArg) != NULL);
+		result = (GetEnvVarOrSpecial(Right) != NULL);
 	}
 	else if (Cmd->If.Operator == IF_ERRORLEVEL)
 	{
@@ -91,7 +106,8 @@ BOOL ExecuteIf(PARSED_COMMAND *Cmd)
 		INT n = _tcstol(Cmd->If.RightArg, &param, 10);
 		if (*param != _T('\0'))
 		{
-			error_syntax(Cmd->If.RightArg);
+			error_syntax(Right);
+			cmd_free(Right);
 			return FALSE;
 		}
 		result = (nErrorLevel >= n);
@@ -102,9 +118,9 @@ BOOL ExecuteIf(PARSED_COMMAND *Cmd)
 		WIN32_FIND_DATA f;
 		HANDLE hFind;
 
-		StripQuotes(Cmd->If.RightArg);
+		StripQuotes(Right);
 
-		hFind = FindFirstFile(Cmd->If.RightArg, &f);
+		hFind = FindFirstFile(Right, &f);
 		if (hFind != INVALID_HANDLE_VALUE)
 		{
 			result = TRUE;
@@ -120,11 +136,11 @@ BOOL ExecuteIf(PARSED_COMMAND *Cmd)
 		if (Cmd->If.Operator == IF_STRINGEQ)
 		{
 			/* IF str1 == str2 */
-			result = StringCmp(Cmd->If.LeftArg, Cmd->If.RightArg) == 0;
+			result = StringCmp(Left, Right) == 0;
 		}
 		else
 		{
-			result = GenericCmp(StringCmp, Cmd->If.LeftArg, Cmd->If.RightArg);
+			result = GenericCmp(StringCmp, Left, Right);
 			switch (Cmd->If.Operator)
 			{
 			case IF_EQU: result = (result == 0); break;
@@ -137,6 +153,9 @@ BOOL ExecuteIf(PARSED_COMMAND *Cmd)
 		}
 	}
 
+	cmd_free(Left);
+	cmd_free(Right);
+
 	if (result ^ ((Cmd->If.Flags & IFFLAG_NEGATE) != 0))
 	{
 		/* full condition was true, do the command */

reactos/base/shell/cmd/redir.c

@@ -54,7 +54,7 @@ BOOL
 PerformRedirection(REDIRECTION *RedirList)
 {
 	REDIRECTION *Redir;
-	TCHAR Filename[MAX_PATH];
+	LPTSTR Filename;
 	HANDLE hNew;
 	UINT DupNumber;
 	static SECURITY_ATTRIBUTES SecAttr = { sizeof(SECURITY_ATTRIBUTES), NULL, TRUE };
@@ -78,8 +78,9 @@ PerformRedirection(REDIRECTION *RedirList)
 
 	for (Redir = RedirList; Redir; Redir = Redir->Next)
 	{
-		*Filename = _T('\0');
-		_tcsncat(Filename, Redir->Filename, MAX_PATH - 1);
+		Filename = DoDelayedExpansion(Redir->Filename);
+		if (!Filename)
+			goto redir_error;
 		StripQuotes(Filename);
 
 		if (*Filename == _T('&'))
@@ -112,6 +113,8 @@ PerformRedirection(REDIRECTION *RedirList)
 		{
 			ConErrResPrintf(Redir->Type == REDIR_READ ? STRING_CMD_ERROR1 : STRING_CMD_ERROR3,
 			                Filename);
+			cmd_free(Filename);
+redir_error:
 			/* Undo all the redirections before this one */
 			UndoRedirection(RedirList, Redir);
 			return FALSE;
@@ -123,6 +126,7 @@ PerformRedirection(REDIRECTION *RedirList)
 		SetHandle(Redir->Number, hNew);
 
 		TRACE("%d redirected to: %s\n", Redir->Number, debugstr_aw(Filename));
+		cmd_free(Filename);
 	}
 	return TRUE;
 }