2 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
3 # Use of this source code is governed by a BSD-style license that can be
4 # found in the LICENSE file.
6 """Prints paths between gyp targets.
14 from collections import deque
19 tools/gyp-explain.py [--dot] chrome_dll# gtest#
23 def GetPath(graph, fro, to):
24 """Given a graph in (node -> list of successor nodes) dictionary format,
25 yields all paths from |fro| to |to|, starting with the shortest."""
26 # Storing full paths in the queue is a bit wasteful, but good enough for this.
27 q = deque([(fro, [])])
33 q.append((d, path + [t]))
36 def MatchNode(graph, substring):
37 """Given a dictionary, returns the key that matches |substring| best. Exits
38 if there's not one single best match."""
41 if substring in target:
42 candidates.append(target)
45 print 'No targets match "%s"' % substring
47 if len(candidates) > 1:
48 print 'More than one target matches "%s": %s' % (
49 substring, ' '.join(candidates))
54 def EscapeForDot(string):
56 if string.endswith(suffix):
57 string = string[:-len(suffix)]
58 string = string.replace('\\', '\\\\')
59 return '"' + string + '"'
62 def GenerateDot(fro, to, paths):
63 """Generates an input file for graphviz's dot program."""
64 prefixes = [os.path.commonprefix(path) for path in paths]
65 prefix = os.path.commonprefix(prefixes)
66 print '// Build with "dot -Tpng -ooutput.png this_file.dot"'
67 # "strict" collapses common paths.
68 print 'strict digraph {'
70 print (' -> '.join(EscapeForDot(item[len(prefix):]) for item in path)), ';'
75 # Check that dump.json exists and that it's not too old.
76 dump_json_dirty = False
78 st = os.stat('dump.json')
79 file_age_s = time.time() - st.st_mtime
80 if file_age_s > 2 * 60 * 60:
81 print 'dump.json is more than 2 hours old.'
82 dump_json_dirty = True
84 print 'dump.json not found.'
85 dump_json_dirty = True
89 print ' GYP_GENERATORS=dump_dependency_json build/gyp_chromium'
90 print 'first, then try again.'
93 g = json.load(open('dump.json'))
95 if len(argv) not in (3, 4):
99 generate_dot = argv[1] == '--dot'
103 fro = MatchNode(g, argv[1])
104 to = MatchNode(g, argv[2])
106 paths = list(GetPath(g, fro, to))
109 GenerateDot(fro, to, paths)
111 print 'These paths lead from %s to %s:' % (fro, to)
113 print ' -> '.join(path)
115 print 'No paths found from %s to %s.' % (fro, to)
118 if __name__ == '__main__':