Revert "it turns out that writeconsole in ansiterm.py is not needed"

This reverts commit 3deaeb241a.

Signed-off-by: Thomas Nagy <tnagy2pow10@gmail.com>

waflib/ansiterm.py

@@ -82,11 +82,7 @@ else:
 
 	class AnsiTerm(object):
 		"""
-		Wrapper for cmd.exe stdio, to support vt100 escape codes
-
-		Notes:
-		- CR printed when the cursor is at EOL will do nothing,
-		  whereas on UNIX, it will go to the line beginning.
+		emulate a vt100 terminal in cmd.exe
 		"""
 		def __init__(self, s):
 			self.stream = s
@@ -271,7 +267,7 @@ else:
 							if cmd_func:
 								cmd_func(self, param)
 						else:
-							self.stream.write(txt)
+							self.writeconsole(txt)
 				else:
 					# no support for colors in the console, just output the text:
 					# eclipse or msys may be able to interpret the escape sequences
@@ -279,11 +275,33 @@ else:
 			finally:
 				wlock.release()
 
+		def writeconsole(self, txt):
+			chars_written = c_int()
+			writeconsole = windll.kernel32.WriteConsoleA
+			if isinstance(txt, _type):
+				writeconsole = windll.kernel32.WriteConsoleW
+
+			# MSDN says that there is a shared buffer of 64 KB for the console
+			# writes. Attempt to not get ERROR_NOT_ENOUGH_MEMORY, see waf issue #746
+			done = 0
+			todo = len(txt)
+			chunk = 32<<10
+			while todo != 0:
+				doing = min(chunk, todo)
+				buf = txt[done:done+doing]
+				r = writeconsole(self.hconsole, buf, doing, byref(chars_written), None)
+				if r == 0:
+					chunk >>= 1
+					continue
+				done += doing
+				todo -= doing
+
+
 		def fileno(self):
 			return self.stream.fileno()
 
 		def flush(self):
-			return self.stream.flush()
+			pass
 
 		def isatty(self):
 			return self._isatty