waf/waflib/extras/why.py

79 lines
1.8 KiB
Python

#! /usr/bin/env python
# encoding: utf-8
# Thomas Nagy, 2010 (ita)
"""
This tool modifies the task signature scheme to store and obtain
information about the task execution (why it must run, etc)::
def configure(conf):
conf.load('why')
After adding the tool, a full rebuild is necessary:
waf clean build --zones=task
"""
from waflib import Task, Utils, Logs, Errors
def signature(self):
# compute the result one time, and suppose the scan_signature will give the good result
try:
return self.cache_sig
except AttributeError:
pass
self.m = Utils.md5()
self.m.update(self.hcode)
id_sig = self.m.digest()
# explicit deps
self.m = Utils.md5()
self.sig_explicit_deps()
exp_sig = self.m.digest()
# env vars
self.m = Utils.md5()
self.sig_vars()
var_sig = self.m.digest()
# implicit deps / scanner results
self.m = Utils.md5()
if self.scan:
try:
self.sig_implicit_deps()
except Errors.TaskRescan:
return self.signature()
impl_sig = self.m.digest()
ret = self.cache_sig = impl_sig + id_sig + exp_sig + var_sig
return ret
Task.Task.signature = signature
old = Task.Task.runnable_status
def runnable_status(self):
ret = old(self)
if ret == Task.RUN_ME:
try:
old_sigs = self.generator.bld.task_sigs[self.uid()]
except (KeyError, AttributeError):
Logs.debug("task: task must run as no previous signature exists")
else:
new_sigs = self.cache_sig
def v(x):
return Utils.to_hex(x)
Logs.debug('Task %r', self)
msgs = ['* Implicit or scanner dependency', '* Task code', '* Source file, explicit or manual dependency', '* Configuration data variable']
tmp = 'task: -> %s: %s %s'
for x in range(len(msgs)):
l = len(Utils.SIG_NIL)
a = new_sigs[x*l : (x+1)*l]
b = old_sigs[x*l : (x+1)*l]
if (a != b):
Logs.debug(tmp, msgs[x].ljust(35), v(a), v(b))
return ret
Task.Task.runnable_status = runnable_status