1#!/usr/bin/env python
2# encoding: utf-8
3# Thomas Nagy, 2008-2010 (ita)
4
5"""
6Execute the tasks with gcc -MD, read the dependencies from the .d file
7and prepare the dependency calculation for the next run.
8This affects the cxx class, so make sure to load Qt5 after this tool.
9
10Usage::
11
12	def options(opt):
13		opt.load('compiler_cxx')
14	def configure(conf):
15		conf.load('compiler_cxx gccdeps')
16"""
17
18import os, re, threading
19from waflib import Task, Logs, Utils, Errors
20from waflib.Tools import c_preproc
21from waflib.TaskGen import before_method, feature
22
23lock = threading.Lock()
24
25gccdeps_flags = ['-MD']
26if not c_preproc.go_absolute:
27	gccdeps_flags = ['-MMD']
28
29# Third-party tools are allowed to add extra names in here with append()
30supported_compilers = ['gcc', 'icc', 'clang']
31
32def scan(self):
33	if not self.__class__.__name__ in self.env.ENABLE_GCCDEPS:
34		return super(self.derived_gccdeps, self).scan()
35	nodes = self.generator.bld.node_deps.get(self.uid(), [])
36	names = []
37	return (nodes, names)
38
39re_o = re.compile(r"\.o$")
40re_splitter = re.compile(r'(?<!\\)\s+') # split by space, except when spaces are escaped
41
42def remove_makefile_rule_lhs(line):
43	# Splitting on a plain colon would accidentally match inside a
44	# Windows absolute-path filename, so we must search for a colon
45	# followed by whitespace to find the divider between LHS and RHS
46	# of the Makefile rule.
47	rulesep = ': '
48
49	sep_idx = line.find(rulesep)
50	if sep_idx >= 0:
51		return line[sep_idx + 2:]
52	else:
53		return line
54
55def path_to_node(base_node, path, cached_nodes):
56	# Take the base node and the path and return a node
57	# Results are cached because searching the node tree is expensive
58	# The following code is executed by threads, it is not safe, so a lock is needed...
59	if getattr(path, '__hash__'):
60		node_lookup_key = (base_node, path)
61	else:
62		# Not hashable, assume it is a list and join into a string
63		node_lookup_key = (base_node, os.path.sep.join(path))
64	try:
65		lock.acquire()
66		node = cached_nodes[node_lookup_key]
67	except KeyError:
68		node = base_node.find_resource(path)
69		cached_nodes[node_lookup_key] = node
70	finally:
71		lock.release()
72	return node
73
74def post_run(self):
75	if not self.__class__.__name__ in self.env.ENABLE_GCCDEPS:
76		return super(self.derived_gccdeps, self).post_run()
77
78	name = self.outputs[0].abspath()
79	name = re_o.sub('.d', name)
80	try:
81		txt = Utils.readf(name)
82	except EnvironmentError:
83		Logs.error('Could not find a .d dependency file, are cflags/cxxflags overwritten?')
84		raise
85	#os.remove(name)
86
87	# Compilers have the choice to either output the file's dependencies
88	# as one large Makefile rule:
89	#
90	#   /path/to/file.o: /path/to/dep1.h \
91	#                    /path/to/dep2.h \
92	#                    /path/to/dep3.h \
93	#                    ...
94	#
95	# or as many individual rules:
96	#
97	#   /path/to/file.o: /path/to/dep1.h
98	#   /path/to/file.o: /path/to/dep2.h
99	#   /path/to/file.o: /path/to/dep3.h
100	#   ...
101	#
102	# So the first step is to sanitize the input by stripping out the left-
103	# hand side of all these lines. After that, whatever remains are the
104	# implicit dependencies of task.outputs[0]
105	txt = '\n'.join([remove_makefile_rule_lhs(line) for line in txt.splitlines()])
106
107	# Now join all the lines together
108	txt = txt.replace('\\\n', '')
109
110	val = txt.strip()
111	val = [x.replace('\\ ', ' ') for x in re_splitter.split(val) if x]
112
113	nodes = []
114	bld = self.generator.bld
115
116	# Dynamically bind to the cache
117	try:
118		cached_nodes = bld.cached_nodes
119	except AttributeError:
120		cached_nodes = bld.cached_nodes = {}
121
122	for x in val:
123
124		node = None
125		if os.path.isabs(x):
126			node = path_to_node(bld.root, x, cached_nodes)
127		else:
128			# TODO waf 1.9 - single cwd value
129			path = getattr(bld, 'cwdx', bld.bldnode)
130			# when calling find_resource, make sure the path does not contain '..'
131			x = [k for k in Utils.split_path(x) if k and k != '.']
132			while '..' in x:
133				idx = x.index('..')
134				if idx == 0:
135					x = x[1:]
136					path = path.parent
137				else:
138					del x[idx]
139					del x[idx-1]
140
141			node = path_to_node(path, x, cached_nodes)
142
143		if not node:
144			raise ValueError('could not find %r for %r' % (x, self))
145		if id(node) == id(self.inputs[0]):
146			# ignore the source file, it is already in the dependencies
147			# this way, successful config tests may be retrieved from the cache
148			continue
149		nodes.append(node)
150
151	Logs.debug('deps: gccdeps for %s returned %s', self, nodes)
152
153	bld.node_deps[self.uid()] = nodes
154	bld.raw_deps[self.uid()] = []
155
156	try:
157		del self.cache_sig
158	except AttributeError:
159		pass
160
161	Task.Task.post_run(self)
162
163def sig_implicit_deps(self):
164	if not self.__class__.__name__ in self.env.ENABLE_GCCDEPS:
165		return super(self.derived_gccdeps, self).sig_implicit_deps()
166	try:
167		return Task.Task.sig_implicit_deps(self)
168	except Errors.WafError:
169		return Utils.SIG_NIL
170
171def wrap_compiled_task(classname):
172	derived_class = type(classname, (Task.classes[classname],), {})
173	derived_class.derived_gccdeps = derived_class
174	derived_class.post_run = post_run
175	derived_class.scan = scan
176	derived_class.sig_implicit_deps = sig_implicit_deps
177
178for k in ('c', 'cxx'):
179	if k in Task.classes:
180		wrap_compiled_task(k)
181
182@before_method('process_source')
183@feature('force_gccdeps')
184def force_gccdeps(self):
185	self.env.ENABLE_GCCDEPS = ['c', 'cxx']
186
187def configure(conf):
188	# in case someone provides a --enable-gccdeps command-line option
189	if not getattr(conf.options, 'enable_gccdeps', True):
190		return
191
192	global gccdeps_flags
193	flags = conf.env.GCCDEPS_FLAGS or gccdeps_flags
194	if conf.env.CC_NAME in supported_compilers:
195		try:
196			conf.check(fragment='int main() { return 0; }', features='c force_gccdeps', cflags=flags, msg='Checking for c flags %r' % ''.join(flags))
197		except Errors.ConfigurationError:
198			pass
199		else:
200			conf.env.append_value('CFLAGS', flags)
201			conf.env.append_unique('ENABLE_GCCDEPS', 'c')
202
203	if conf.env.CXX_NAME in supported_compilers:
204		try:
205			conf.check(fragment='int main() { return 0; }', features='cxx force_gccdeps', cxxflags=flags, msg='Checking for cxx flags %r' % ''.join(flags))
206		except Errors.ConfigurationError:
207			pass
208		else:
209			conf.env.append_value('CXXFLAGS', flags)
210			conf.env.append_unique('ENABLE_GCCDEPS', 'cxx')
211
212def options(opt):
213	raise ValueError('Do not load gccdeps options')
214
215