From a933244f48302ffd8d83a68c5a1a8f28baa820bf Mon Sep 17 00:00:00 2001
From: Thomas Nagy <tnagy2pow10@gmail.com>
Date: Mon, 23 Feb 2015 10:44:57 +0100
Subject: [PATCH] Enable unity builds for C too

---
 waflib/Scripting.py    |   2 +-
 waflib/extras/unity.py | 121 +++++++++++++++++++++++------------------
 2 files changed, 69 insertions(+), 54 deletions(-)

diff --git a/waflib/Scripting.py b/waflib/Scripting.py
index e48f1ff8..7cb5910f 100644
--- a/waflib/Scripting.py
+++ b/waflib/Scripting.py
@@ -144,7 +144,7 @@ def waf_entry_point(current_directory, version, wafdir):
 	import cProfile, pstats
 	cProfile.runctx("from waflib import Scripting; Scripting.run_commands()", {}, {}, 'profi.txt')
 	p = pstats.Stats('profi.txt')
-	p.sort_stats('time').print_stats(25) # or 'cumulative'
+	p.sort_stats('time').print_stats(75) # or 'cumulative'
 	"""
 	try:
 		run_commands()
diff --git a/waflib/extras/unity.py b/waflib/extras/unity.py
index 1938dcf1..d21e3519 100644
--- a/waflib/extras/unity.py
+++ b/waflib/extras/unity.py
@@ -1,53 +1,68 @@
-#! /usr/bin/env python
-# encoding: utf-8
-
-"""
-Take a group of C++ files and compile them at once.
-
-def options(opt):
-	opt.load('compiler_cxx unity')
-"""
-
-from waflib import Task, Options
-from waflib.Tools import ccroot, cxx, c_preproc
-from waflib.TaskGen import extension, taskgen_method
-
-MAX_BATCH = 50
-
-def options(opt):
-	global MAX_BATCH
-	opt.add_option('--batchsize', action='store', dest='batchsize', type='int', default=MAX_BATCH, help='batch size (0 for no batch)')
-
-class unity(Task.Task):
-	color = 'BLUE'
-	scan = c_preproc.scan
-	def run(self):
-		lst = ['#include "%s"\n' % node.abspath() for node in self.inputs]
-		txt = ''.join(lst)
-		self.outputs[0].write(txt)
-
-@taskgen_method
-def batch_size(self):
-	return Options.options.batchsize
-
-@extension('.cpp', '.cc', '.cxx', '.C', '.c++')
-def make_cxx_batch(self, node):
-	cnt = self.batch_size()
-	if cnt <= 1:
-		tsk = self.create_compiled_task('cxx', node)
-		return tsk
-
-	try:
-		self.cnt_cxx
-	except AttributeError:
-		self.cnt_cxx = 0
-
-	x = getattr(self, 'master_cxx', None)
-	if not x or len(x.inputs) >= cnt:
-		x = self.master_cxx = self.create_task('unity')
-		cxxnode = node.parent.find_or_declare('union_%s_%d_%d.cxx' % (self.idx, self.cnt_cxx, cnt))
-		self.master_cxx.outputs = [cxxnode]
-		self.cnt_cxx += 1
-		self.create_compiled_task('cxx', cxxnode)
-	x.inputs.append(node)
-
+#! /usr/bin/env python
+# encoding: utf-8
+
+"""
+Compile whole groups of C/C++ files at once.
+
+def build(bld):
+	bld.load('compiler_cxx unity')
+"""
+
+import sys
+from waflib import Task, Options
+from waflib.Tools import c_preproc
+from waflib import TaskGen
+
+MAX_BATCH = 50
+
+def options(opt):
+	global MAX_BATCH
+	opt.add_option('--batchsize', action='store', dest='batchsize', type='int', default=MAX_BATCH, help='batch size (0 for no batch)')
+
+class unity(Task.Task):
+	color = 'BLUE'
+	scan = c_preproc.scan
+	def run(self):
+		lst = ['#include "%s"\n' % node.abspath() for node in self.inputs]
+		txt = ''.join(lst)
+		self.outputs[0].write(txt)
+
+@TaskGen.taskgen_method
+def batch_size(self):
+	return getattr(Options.options, 'batchsize', MAX_BATCH)
+
+def make_batch_fun(ext):
+	# this generic code makes this quite unreadable, defining the function two times might have been better
+	def make_batch(self, node):
+		cnt = self.batch_size()
+		if cnt <= 1:
+			return self.create_compiled_task(ext, node)
+		x = getattr(self, 'master_%s' % ext, None)
+		if not x or len(x.inputs) >= cnt:
+			x = self.create_task('unity')
+			setattr(self, 'master_%s' % ext, x)
+
+			cnt_cur = getattr(self, 'cnt_%s' % ext, 0)
+			cxxnode = node.parent.find_or_declare('unity_%s_%d_%d.%s' % (self.idx, cnt_cur, cnt, ext))
+			x.outputs = [cxxnode]
+			setattr(self, 'cnt_%s' % ext, cnt_cur + 1)
+			self.create_compiled_task(ext, cxxnode)
+		x.inputs.append(node)
+	return make_batch
+
+def enable_support(cc, cxx):
+	if cxx or not cc:
+		make_cxx_batch = TaskGen.extension('.cpp', '.cc', '.cxx', '.C', '.c++')(make_batch_fun('cxx'))
+	if cc:
+		make_c_batch = TaskGen.extension('.c')(make_batch_fun('c'))
+	else:
+		TaskGen.task_gen.mappings['.c'] = TaskGen.task_gen.mappings['.cpp']
+
+has_c = '.c' in TaskGen.task_gen.mappings or 'waflib.Tools.compiler_c' in sys.modules
+has_cpp = '.cpp' in TaskGen.task_gen.mappings or 'waflib.Tools.compiler_cxx' in sys.modules
+enable_support(has_c, has_cpp) # by default
+
+def build(bld):
+	# it is best to do this
+	enable_support(bld.env.CC_NAME, bld.env.CXX_NAME)
+