[jmorlan] 39848: Speed up batch file execution by reading a line at a time instead of a byte at a time.

Author: jmorlan
Date: Mon Mar  2 23:00:26 2009
New Revision: 39848

URL: http://svn.reactos.org/svn/reactos?rev=39848&view=rev
Log:
Speed up batch file execution by reading a line at a time instead of a byte at a time.

Modified:
    trunk/reactos/base/shell/cmd/misc.c

Modified: trunk/reactos/base/shell/cmd/misc.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/base/shell/cmd/misc.c?rev=…
==============================================================================
--- trunk/reactos/base/shell/cmd/misc.c [iso-8859-1] (original)
+++ trunk/reactos/base/shell/cmd/misc.c [iso-8859-1] Mon Mar  2 23:00:26 2009
@@ -503,7 +503,6 @@
 BOOL FileGetString (HANDLE hFile, LPTSTR lpBuffer, INT nBufferLength)
 {
 	LPSTR lpString;
-	CHAR ch;
 	DWORD  dwRead;
 	INT len = 0;
 #ifdef _UNICODE
@@ -511,18 +510,20 @@
 #else
 	lpString = lpBuffer;
 #endif
-	while ((--nBufferLength >  0) &&
-		   ReadFile(hFile, &ch, 1, &dwRead, NULL) && dwRead)
-	{
-        lpString[len++] = ch;
-        if (ch == '\n')
-		{
-			/* break at new line*/
-			break;
-		}
-	}
-
-	if (!dwRead && !len)
+
+	if (ReadFile(hFile, lpString, nBufferLength - 1, &dwRead, NULL))
+	{
+		/* break at new line*/
+		CHAR *end = memchr(lpString, '\n', dwRead);
+		len = dwRead;
+		if (end)
+		{
+			len = (end - lpString) + 1;
+			SetFilePointer(hFile, len - dwRead, NULL, FILE_CURRENT);
+		}
+	}
+
+	if (!len)
 	{
 #ifdef _UNICODE
 		cmd_free(lpString);