build: Adding waf as a build system

Change-Id: If5074b252bc30c2fdcc28ae94cb7ad2858a25d9f
diff --git a/.waf-tools/sphinx_build.py b/.waf-tools/sphinx_build.py
new file mode 100644
index 0000000..e1155d1
--- /dev/null
+++ b/.waf-tools/sphinx_build.py
@@ -0,0 +1,108 @@
+#!/usr/bin/env python
+# encoding: utf-8
+# Hans-Martin von Gaudecker, 2012
+
+"""
+Create Sphinx documentation. Currently only LaTeX and HTML are supported.
+
+The source file **must** be the conf.py file used by Sphinx. Everything
+else has defaults, passing in the parameters is optional.
+
+Usage for getting both html and pdf docs:
+
+    ctx(features='sphinx', source='docs/conf.py')
+    ctx(features='sphinx', source='docs/conf.py', buildername='latex')
+
+Optional parameters and their defaults:
+
+    * buildername: html
+    * srcdir: confdir (the directory where conf.py lives)
+    * outdir: confdir/buildername (in the build directory tree)
+    * doctreedir: outdir/.doctrees
+    * type: pdflatex (only applies to 'latex' builder)
+
+"""
+
+
+import os
+from waflib import Task, TaskGen, Errors, Logs
+
+class RunSphinxBuild(Task.Task):
+	def scan(self):
+		"""Use Sphinx' internal environment to find the dependencies."""
+		s = self.sphinx_instance
+		msg, dummy, iterator = s.env.update(s.config, s.srcdir, s.doctreedir, s)
+		s.info(msg)
+		dep_nodes = []
+		for docname in s.builder.status_iterator(iterator, "reading sources... "):
+			filename = docname + s.config.source_suffix
+			dep_nodes.append(self.srcdir.find_node(filename))
+		for dep in s.env.dependencies.values():
+			# Need the 'str' call because Sphinx might return Unicode strings.
+			[dep_nodes.append(self.srcdir.find_node(str(d))) for d in dep]
+		return (dep_nodes, [])
+
+	def run(self):
+		"""Run the Sphinx build."""
+		self.sphinx_instance.build(force_all=False, filenames=None)
+		return None
+
+	def post_run(self):
+		"""Add everything found in the output directory tree as an output.
+		Not elegant, but pragmatic."""
+		for n in self.outdir.ant_glob("**", quiet=True, remove=False):
+			if n not in self.outputs: self.set_outputs(n)
+		super(RunSphinxBuild, self).post_run()
+
+
+def _get_main_targets(tg, s):
+	"""Return some easy targets known from the Sphinx build environment **s.env**."""
+	out_dir = tg.bld.root.find_node(s.outdir)
+	tgt_nodes = []
+	if s.builder.name == "latex":
+		for tgt_info in s.env.config.latex_documents:
+			tgt_nodes.append(out_dir.find_or_declare(tgt_info[1]))
+	elif s.builder.name == "html":
+		suffix = getattr(s.env.config, "html_file_suffix", ".html")
+		tgt_name = s.env.config.master_doc + suffix
+		tgt_nodes.append(out_dir.find_or_declare(tgt_name))
+	else:
+		raise Errors.WafError("Sphinx builder not implemented: %s" % s.builder.name)
+	return tgt_nodes
+
+
+@TaskGen.feature("sphinx")
+@TaskGen.before_method("process_source")
+def apply_sphinx(tg):
+	"""Set up the task generator with a Sphinx instance and create a task."""
+
+        from sphinx.application import Sphinx
+
+	# Put together the configuration based on defaults and tg attributes.
+	conf = tg.path.find_node(tg.source)
+	confdir = conf.parent.abspath()
+	buildername = getattr(tg, "buildername", "html")
+	srcdir = getattr(tg, "srcdir", confdir)
+	outdir = tg.path.find_or_declare (getattr(tg, "outdir", os.path.join(conf.parent.get_bld().abspath(), buildername))).abspath ()
+        
+	doctreedir = getattr(tg, "doctreedir", os.path.join(outdir, ".doctrees"))
+
+	# Set up the Sphinx instance.
+	s = Sphinx (srcdir, confdir, outdir, doctreedir, buildername, status=None)
+
+	# Get the main targets of the Sphinx build.
+	tgt_nodes = _get_main_targets(tg, s)
+
+	# Create the task and set the required attributes.  
+	task = tg.create_task("RunSphinxBuild", src=conf, tgt=tgt_nodes)
+	task.srcdir = tg.bld.root.find_node(s.srcdir)
+	task.outdir = tg.bld.root.find_node(s.outdir)
+	task.sphinx_instance = s
+
+	# Build pdf if we have the LaTeX builder, allow for building with xelatex.
+	if s.builder.name == "latex":
+		compile_type = getattr(tg, "type", "pdflatex")
+		tg.bld(features="tex", type=compile_type, source=tgt_nodes, name="sphinx_pdf", prompt=0)
+
+	# Bypass the execution of process_source by setting the source to an empty list
+	tg.source = []