# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
#
+from __future__ import generators ### KEEP FOR COMPATIBILITY FIXERS
__doc__ = """
Generic Taskmaster module for the SCons build engine.
__revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
-import string
+from itertools import chain
+import operator
import sys
import traceback
-import SCons.Node
import SCons.Errors
+import SCons.Node
+import SCons.Warnings
StateString = SCons.Node.StateString
-
+NODE_NO_STATE = SCons.Node.no_state
+NODE_PENDING = SCons.Node.pending
+NODE_EXECUTING = SCons.Node.executing
+NODE_UP_TO_DATE = SCons.Node.up_to_date
+NODE_EXECUTED = SCons.Node.executed
+NODE_FAILED = SCons.Node.failed
# A subsystem for recording stats about how different Nodes are handled by
self.node = node
self.exc_clear()
+ def trace_message(self, method, node, description='node'):
+ fmt = '%-20s %s %s\n'
+ return fmt % (method + ':', description, self.tm.trace_node(node))
+
def display(self, message):
"""
Hook to allow the calling interface to display a message.
unlink underlying files and make all necessary directories before
the Action is actually called to build the targets.
"""
+ T = self.tm.trace
+ if T: T.write(self.trace_message('Task.prepare()', self.node))
# Now that it's the appropriate time, give the TaskMaster a
# chance to raise any exceptions it encountered while preparing
self.display(self.tm.message)
self.tm.message = None
- for t in self.targets:
+ # Let the targets take care of any necessary preparations.
+ # This includes verifying that all of the necessary sources
+ # and dependencies exist, removing the target file(s), etc.
+ #
+ # As of April 2008, the get_executor().prepare() method makes
+ # sure that all of the aggregate sources necessary to build this
+ # Task's target(s) exist in one up-front check. The individual
+ # target t.prepare() methods check that each target's explicit
+ # or implicit dependencies exists, and also initialize the
+ # .sconsign info.
+ executor = self.targets[0].get_executor()
+ executor.prepare()
+ for t in executor.get_action_targets():
t.prepare()
for s in t.side_effects:
s.prepare()
"""
return self.node
+ def needs_execute(self):
+ # TODO(deprecate): "return True" is the old default behavior;
+ # change it to NotImplementedError (after running through the
+ # Deprecation Cycle) so the desired behavior is explicitly
+ # determined by which concrete subclass is used.
+ #raise NotImplementedError
+ msg = ('Direct use of the Taskmaster.Task class will be deprecated\n'
+ + '\tin a future release.')
+ SCons.Warnings.warn(SCons.Warnings.TaskmasterNeedsExecuteWarning, msg)
+ return True
+
def execute(self):
"""
Called to execute the task.
so only do thread safe stuff here. Do thread unsafe stuff in
prepare(), executed() or failed().
"""
+ T = self.tm.trace
+ if T: T.write(self.trace_message('Task.execute()', self.node))
try:
everything_was_cached = 1
for t in self.targets:
- if not t.retrieve_from_cache():
+ if t.retrieve_from_cache():
+ # Call the .built() method without calling the
+ # .push_to_cache() method, since we just got the
+ # target from the cache and don't need to push
+ # it back there.
+ t.set_state(NODE_EXECUTED)
+ t.built()
+ else:
everything_was_cached = 0
break
if not everything_was_cached:
self.targets[0].build()
- except KeyboardInterrupt:
- raise
except SystemExit:
exc_value = sys.exc_info()[1]
raise SCons.Errors.ExplicitExit(self.targets[0], exc_value.code)
raise
except SCons.Errors.BuildError:
raise
- except:
- raise SCons.Errors.TaskmasterException(self.targets[0],
- sys.exc_info())
+ except Exception, e:
+ buildError = SCons.Errors.convert_to_BuildError(e)
+ buildError.node = self.targets[0]
+ buildError.exc_info = sys.exc_info()
+ raise buildError
+
+ def executed_without_callbacks(self):
+ """
+ Called when the task has been successfully executed
+ and the Taskmaster instance doesn't want to call
+ the Node's callback methods.
+ """
+ T = self.tm.trace
+ if T: T.write(self.trace_message('Task.executed_without_callbacks()',
+ self.node))
- def executed(self):
+ for t in self.targets:
+ if t.get_state() == NODE_EXECUTING:
+ for side_effect in t.side_effects:
+ side_effect.set_state(NODE_NO_STATE)
+ t.set_state(NODE_EXECUTED)
+
+ def executed_with_callbacks(self):
"""
- Called when the task has been successfully executed.
+ Called when the task has been successfully executed and
+ the Taskmaster instance wants to call the Node's callback
+ methods.
This may have been a do-nothing operation (to preserve build
- order), so we have to check the node's state before deciding
- whether it was "built" or just "visited."
+ order), so we must check the node's state before deciding whether
+ it was "built", in which case we call the appropriate Node method.
+ In any event, we always call "visited()", which will handle any
+ post-visit actions that must take place regardless of whether
+ or not the target was an actual built target or a source Node.
"""
+ T = self.tm.trace
+ if T: T.write(self.trace_message('Task.executed_with_callbacks()',
+ self.node))
+
for t in self.targets:
- if t.get_state() == SCons.Node.executing:
- t.set_state(SCons.Node.executed)
+ if t.get_state() == NODE_EXECUTING:
+ for side_effect in t.side_effects:
+ side_effect.set_state(NODE_NO_STATE)
+ t.set_state(NODE_EXECUTED)
+ t.push_to_cache()
t.built()
- else:
- t.visited()
+ t.visited()
+
+ executed = executed_with_callbacks
def failed(self):
"""
Default action when a task fails: stop the build.
+
+ Note: Although this function is normally invoked on nodes in
+ the executing state, it might also be invoked on up-to-date
+ nodes when using Configure().
"""
self.fail_stop()
def fail_stop(self):
"""
Explicit stop-the-build failure.
+
+ This sets failure status on the target nodes and all of
+ their dependent parent nodes.
+
+ Note: Although this function is normally invoked on nodes in
+ the executing state, it might also be invoked on up-to-date
+ nodes when using Configure().
"""
- for t in self.targets:
- t.set_state(SCons.Node.failed)
+ T = self.tm.trace
+ if T: T.write(self.trace_message('Task.failed_stop()', self.node))
+
+ # Invoke will_not_build() to clean-up the pending children
+ # list.
+ self.tm.will_not_build(self.targets, lambda n: n.set_state(NODE_FAILED))
+
+ # Tell the taskmaster to not start any new tasks
self.tm.stop()
# We're stopping because of a build failure, but give the
This sets failure status on the target nodes and all of
their dependent parent nodes.
+
+ Note: Although this function is normally invoked on nodes in
+ the executing state, it might also be invoked on up-to-date
+ nodes when using Configure().
"""
- for t in self.targets:
- # Set failure state on all of the parents that were dependent
- # on this failed build.
- def set_state(node): node.set_state(SCons.Node.failed)
- t.call_for_all_waiting_parents(set_state)
+ T = self.tm.trace
+ if T: T.write(self.trace_message('Task.failed_continue()', self.node))
+
+ self.tm.will_not_build(self.targets, lambda n: n.set_state(NODE_FAILED))
def make_ready_all(self):
"""
This is used when the interface needs every target Node to be
visited--the canonical example being the "scons -c" option.
"""
+ T = self.tm.trace
+ if T: T.write(self.trace_message('Task.make_ready_all()', self.node))
+
self.out_of_date = self.targets[:]
for t in self.targets:
- t.disambiguate().set_state(SCons.Node.executing)
+ t.disambiguate().set_state(NODE_EXECUTING)
for s in t.side_effects:
- s.set_state(SCons.Node.executing)
+ # add disambiguate here to mirror the call on targets above
+ s.disambiguate().set_state(NODE_EXECUTING)
def make_ready_current(self):
"""
This is the default behavior for building only what's necessary.
"""
+ T = self.tm.trace
+ if T: T.write(self.trace_message('Task.make_ready_current()',
+ self.node))
+
self.out_of_date = []
+ needs_executing = False
for t in self.targets:
- if t.disambiguate().current():
- t.set_state(SCons.Node.up_to_date)
- else:
+ try:
+ t.disambiguate().make_ready()
+ is_up_to_date = not t.has_builder() or \
+ (not t.always_build and t.is_up_to_date())
+ except EnvironmentError, e:
+ raise SCons.Errors.BuildError(node=t, errstr=e.strerror, filename=e.filename)
+
+ if not is_up_to_date:
self.out_of_date.append(t)
- t.set_state(SCons.Node.executing)
+ needs_executing = True
+
+ if needs_executing:
+ for t in self.targets:
+ t.set_state(NODE_EXECUTING)
for s in t.side_effects:
- s.set_state(SCons.Node.executing)
+ # add disambiguate here to mirror the call on targets in first loop above
+ s.disambiguate().set_state(NODE_EXECUTING)
+ else:
+ for t in self.targets:
+ # We must invoke visited() to ensure that the node
+ # information has been computed before allowing the
+ # parent nodes to execute. (That could occur in a
+ # parallel build...)
+ t.visited()
+ t.set_state(NODE_UP_TO_DATE)
make_ready = make_ready_current
waiting parent Nodes, or Nodes waiting on a common side effect,
that can be put back on the candidates list.
"""
+ T = self.tm.trace
+ if T: T.write(self.trace_message('Task.postprocess()', self.node))
# We may have built multiple targets, some of which may have
# common parents waiting for this build. Count up how many
# back on the candidates list if the Node is also a waiting
# parent.
+ targets = set(self.targets)
+
+ pending_children = self.tm.pending_children
parents = {}
- for t in self.targets:
- for p in t.waiting_parents.keys():
+ for t in targets:
+ # A node can only be in the pending_children set if it has
+ # some waiting_parents.
+ if t.waiting_parents:
+ if T: T.write(self.trace_message('Task.postprocess()',
+ t,
+ 'removing'))
+ pending_children.discard(t)
+ for p in t.waiting_parents:
parents[p] = parents.get(p, 0) + 1
- for t in self.targets:
+ for t in targets:
for s in t.side_effects:
- if s.get_state() == SCons.Node.executing:
- s.set_state(SCons.Node.no_state)
- for p in s.waiting_parents.keys():
- if not parents.has_key(p):
- parents[p] = 1
- for p in s.waiting_s_e.keys():
+ if s.get_state() == NODE_EXECUTING:
+ s.set_state(NODE_NO_STATE)
+ for p in s.waiting_parents:
+ parents[p] = parents.get(p, 0) + 1
+ for p in s.waiting_s_e:
if p.ref_count == 0:
self.tm.candidates.append(p)
for p, subtract in parents.items():
p.ref_count = p.ref_count - subtract
+ if T: T.write(self.trace_message('Task.postprocess()',
+ p,
+ 'adjusted parent ref count'))
if p.ref_count == 0:
self.tm.candidates.append(p)
- for t in self.targets:
+ for t in targets:
t.postprocess()
# Exception handling subsystem.
exc_traceback = None
raise exc_type, exc_value, exc_traceback
+class AlwaysTask(Task):
+ def needs_execute(self):
+ """
+ Always returns True (indicating this Task should always
+ be executed).
+
+ Subclasses that need this behavior (as opposed to the default
+ of only executing Nodes that are out of date w.r.t. their
+ dependencies) can use this as follows:
+
+ class MyTaskSubclass(SCons.Taskmaster.Task):
+ needs_execute = SCons.Taskmaster.Task.execute_always
+ """
+ return True
+
+class OutOfDateTask(Task):
+ def needs_execute(self):
+ """
+ Returns True (indicating this Task should be executed) if this
+ Task's target state indicates it needs executing, which has
+ already been determined by an earlier up-to-date check.
+ """
+ return self.targets[0].get_state() == SCons.Node.executing
+
-def find_cycle(stack):
- if stack[0] == stack[-1]:
- return stack
- for n in stack[-1].waiting_parents.keys():
+def find_cycle(stack, visited):
+ if stack[-1] in visited:
+ return None
+ visited.add(stack[-1])
+ for n in stack[-1].waiting_parents:
stack.append(n)
- if find_cycle(stack):
+ if stack[0] == stack[-1]:
+ return stack
+ if find_cycle(stack, visited):
return stack
stack.pop()
return None
The Taskmaster for walking the dependency DAG.
"""
- def __init__(self, targets=[], tasker=Task, order=None, trace=None):
- self.top_targets = targets[:]
- self.top_targets.reverse()
+ def __init__(self, targets=[], tasker=None, order=None, trace=None):
+ self.original_top = targets
+ self.top_targets_left = targets[:]
+ self.top_targets_left.reverse()
self.candidates = []
+ if tasker is None:
+ tasker = OutOfDateTask
self.tasker = tasker
if not order:
order = lambda l: l
self.message = None
self.trace = trace
self.next_candidate = self.find_next_candidate
+ self.pending_children = set()
def find_next_candidate(self):
"""
except IndexError:
pass
try:
- node = self.top_targets.pop()
+ node = self.top_targets_left.pop()
except IndexError:
return None
self.current_top = node
def no_next_candidate(self):
"""
Stops Taskmaster processing by not returning a next candidate.
+
+ Note that we have to clean-up the Taskmaster candidate list
+ because the cycle detection depends on the fact all nodes have
+ been processed somehow.
"""
+ while self.candidates:
+ candidates = self.candidates
+ self.candidates = []
+ self.will_not_build(candidates)
return None
+ def _validate_pending_children(self):
+ """
+ Validate the content of the pending_children set. Assert if an
+ internal error is found.
+
+ This function is used strictly for debugging the taskmaster by
+ checking that no invariants are violated. It is not used in
+ normal operation.
+
+ The pending_children set is used to detect cycles in the
+ dependency graph. We call a "pending child" a child that is
+ found in the "pending" state when checking the dependencies of
+ its parent node.
+
+ A pending child can occur when the Taskmaster completes a loop
+ through a cycle. For example, lets imagine a graph made of
+ three node (A, B and C) making a cycle. The evaluation starts
+ at node A. The taskmaster first consider whether node A's
+ child B is up-to-date. Then, recursively, node B needs to
+ check whether node C is up-to-date. This leaves us with a
+ dependency graph looking like:
+
+ Next candidate \
+ \
+ Node A (Pending) --> Node B(Pending) --> Node C (NoState)
+ ^ |
+ | |
+ +-------------------------------------+
+
+ Now, when the Taskmaster examines the Node C's child Node A,
+ it finds that Node A is in the "pending" state. Therefore,
+ Node A is a pending child of node C.
+
+ Pending children indicate that the Taskmaster has potentially
+ loop back through a cycle. We say potentially because it could
+ also occur when a DAG is evaluated in parallel. For example,
+ consider the following graph:
+
+
+ Node A (Pending) --> Node B(Pending) --> Node C (Pending) --> ...
+ | ^
+ | |
+ +----------> Node D (NoState) --------+
+ /
+ Next candidate /
+
+ The Taskmaster first evaluates the nodes A, B, and C and
+ starts building some children of node C. Assuming, that the
+ maximum parallel level has not been reached, the Taskmaster
+ will examine Node D. It will find that Node C is a pending
+ child of Node D.
+
+ In summary, evaluating a graph with a cycle will always
+ involve a pending child at one point. A pending child might
+ indicate either a cycle or a diamond-shaped DAG. Only a
+ fraction of the nodes ends-up being a "pending child" of
+ another node. This keeps the pending_children set small in
+ practice.
+
+ We can differentiate between the two cases if we wait until
+ the end of the build. At this point, all the pending children
+ nodes due to a diamond-shaped DAG will have been properly
+ built (or will have failed to build). But, the pending
+ children involved in a cycle will still be in the pending
+ state.
+
+ The taskmaster removes nodes from the pending_children set as
+ soon as a pending_children node moves out of the pending
+ state. This also helps to keep the pending_children set small.
+ """
+
+ for n in self.pending_children:
+ assert n.state in (NODE_PENDING, NODE_EXECUTING), \
+ (str(n), StateString[n.state])
+ assert len(n.waiting_parents) != 0, (str(n), len(n.waiting_parents))
+ for p in n.waiting_parents:
+ assert p.ref_count > 0, (str(n), str(p), p.ref_count)
+
+
+ def trace_message(self, message):
+ return 'Taskmaster: %s\n' % message
+
+ def trace_node(self, node):
+ return '<%-10s %-3s %s>' % (StateString[node.get_state()],
+ node.ref_count,
+ repr(str(node)))
+
def _find_next_ready_node(self):
"""
Finds the next node that is ready to be built.
self.ready_exc = None
T = self.trace
+ if T: T.write('\n' + self.trace_message('Looking for a node to evaluate'))
- while 1:
+ while True:
node = self.next_candidate()
if node is None:
+ if T: T.write(self.trace_message('No candidate anymore.') + '\n')
return None
node = node.disambiguate()
state = node.get_state()
+ # For debugging only:
+ #
+ # try:
+ # self._validate_pending_children()
+ # except:
+ # self.ready_exc = sys.exc_info()
+ # return node
+
if CollectStats:
if not hasattr(node, 'stats'):
node.stats = Stats()
else:
S = None
- if T: T.write('Taskmaster: %s:' % repr(str(node)))
+ if T: T.write(self.trace_message(' Considering node %s and its children:' % self.trace_node(node)))
- # Skip this node if it has already been evaluated:
- if state > SCons.Node.pending:
+ if state == NODE_NO_STATE:
+ # Mark this node as being on the execution stack:
+ node.set_state(NODE_PENDING)
+ elif state > NODE_PENDING:
+ # Skip this node if it has already been evaluated:
if S: S.already_handled = S.already_handled + 1
- if T: T.write(' already handled (%s)\n' % StateString[state])
+ if T: T.write(self.trace_message(' already handled (executed)'))
continue
- # Mark this node as being on the execution stack:
- node.set_state(SCons.Node.pending)
+ executor = node.get_executor()
try:
- children = node.children()
+ children = executor.get_all_children()
except SystemExit:
exc_value = sys.exc_info()[1]
e = SCons.Errors.ExplicitExit(node, exc_value.code)
self.ready_exc = (SCons.Errors.ExplicitExit, e)
- if T: T.write(' SystemExit\n')
+ if T: T.write(self.trace_message(' SystemExit'))
return node
- except KeyboardInterrupt:
- if T: T.write(' KeyboardInterrupt\n')
- raise
- except:
+ except Exception, e:
# We had a problem just trying to figure out the
# children (like a child couldn't be linked in to a
- # BuildDir, or a Scanner threw something). Arrange to
+ # VariantDir, or a Scanner threw something). Arrange to
# raise the exception when the Task is "executed."
self.ready_exc = sys.exc_info()
if S: S.problem = S.problem + 1
- if T: T.write(' exception\n')
+ if T: T.write(self.trace_message(' exception %s while scanning children.\n' % e))
return node
- if T and children:
- c = map(str, children)
- c.sort()
- T.write(' children:\n %s\n ' % c)
-
- childinfo = map(lambda N: (N.get_state(),
- N.is_derived() or N.is_pseudo_derived(),
- N), children)
-
- # Skip this node if any of its children have failed. This
- # catches the case where we're descending a top-level target
- # and one of our children failed while trying to be built
- # by a *previous* descent of an earlier top-level target.
- failed_children = filter(lambda I: I[0] == SCons.Node.failed,
- childinfo)
- if failed_children:
- node.set_state(SCons.Node.failed)
- if S: S.child_failed = S.child_failed + 1
- if T:
- c = map(str, failed_children)
- c.sort()
- T.write(' children failed:\n %s\n' % c)
- continue
+ children_not_visited = []
+ children_pending = set()
+ children_not_ready = []
+ children_failed = False
+
+ for child in chain(executor.get_all_prerequisites(), children):
+ childstate = child.get_state()
+
+ if T: T.write(self.trace_message(' ' + self.trace_node(child)))
+
+ if childstate == NODE_NO_STATE:
+ children_not_visited.append(child)
+ elif childstate == NODE_PENDING:
+ children_pending.add(child)
+ elif childstate == NODE_FAILED:
+ children_failed = True
+
+ if childstate <= NODE_EXECUTING:
+ children_not_ready.append(child)
+
+
+ # These nodes have not even been visited yet. Add
+ # them to the list so that on some next pass we can
+ # take a stab at evaluating them (or their children).
+ children_not_visited.reverse()
+ self.candidates.extend(self.order(children_not_visited))
+ #if T and children_not_visited:
+ # T.write(self.trace_message(' adding to candidates: %s' % map(str, children_not_visited)))
+ # T.write(self.trace_message(' candidates now: %s\n' % map(str, self.candidates)))
+
+ # Skip this node if any of its children have failed.
+ #
+ # This catches the case where we're descending a top-level
+ # target and one of our children failed while trying to be
+ # built by a *previous* descent of an earlier top-level
+ # target.
+ #
+ # It can also occur if a node is reused in multiple
+ # targets. One first descends though the one of the
+ # target, the next time occurs through the other target.
+ #
+ # Note that we can only have failed_children if the
+ # --keep-going flag was used, because without it the build
+ # will stop before diving in the other branch.
+ #
+ # Note that even if one of the children fails, we still
+ # added the other children to the list of candidate nodes
+ # to keep on building (--keep-going).
+ if children_failed:
+ for n in executor.get_action_targets():
+ n.set_state(NODE_FAILED)
- # Detect dependency cycles:
- pending_nodes = filter(lambda I: I[0] == SCons.Node.pending, childinfo)
- if pending_nodes:
- for p in pending_nodes:
- cycle = find_cycle([p[2], node])
- if cycle:
- desc = "Dependency cycle: " + string.join(map(str, cycle), " -> ")
- if T: T.write(' dependency cycle\n')
- raise SCons.Errors.UserError, desc
-
- # Select all of the dependencies that are derived targets
- # (that is, children who have builders or are side effects).
- derived_children = filter(lambda I: I[1], childinfo)
-
- not_started = filter(lambda I: not I[0], derived_children)
- if not_started:
- not_started = map(lambda I: I[2], not_started)
-
- # We're waiting on one more derived targets that have
- # not yet started building. Add this node to the
- # waiting_parents lists of those derived files so that
- # when they've finished building, our implicit dependency
- # list will get cleared and we'll re-scan the newly-built
- # file(s) for updated implicit dependencies.
- map(lambda n, P=node: n.add_to_waiting_parents(P), not_started)
- node.ref_count = len(not_started)
-
- # Now we add these derived targets to the candidates
- # list so they can be examined and built. We have to
- # add ourselves back to the list first, though, so we get
- # a chance to re-scan and build after the dependencies.
- #
- # We reverse the order in which the children are added
- # to the candidates stack so the order in which they're
- # popped matches the order in which they show up in our
- # children's list. This is more logical / efficient for
- # builders with multiple targets, since the "primary"
- # target will be examined first.
- self.candidates.append(node)
- not_started.reverse()
- self.candidates.extend(self.order(not_started))
-
- if S: S.not_started = S.not_started + 1
- if T:
- c = map(str, not_started)
- c.sort()
- T.write(' waiting on unstarted children:\n %s\n' % c)
+ if S: S.child_failed = S.child_failed + 1
+ if T: T.write(self.trace_message('****** %s\n' % self.trace_node(node)))
continue
- not_built = filter(lambda I: I[0] <= SCons.Node.executing, derived_children)
- if not_built:
- not_built = map(lambda I: I[2], not_built)
+ if children_not_ready:
+ for child in children_not_ready:
+ # We're waiting on one or more derived targets
+ # that have not yet finished building.
+ if S: S.not_built = S.not_built + 1
- # We're waiting on one or more derived targets that have
- # started building but not yet finished. Add this node
- # to the waiting parents lists of those derived files
- # so that when they've finished building, our implicit
- # dependency list will get cleared and we'll re-scan the
- # newly-built file(s) for updated implicit dependencies.
- map(lambda n, P=node: n.add_to_waiting_parents(P), not_built)
- node.ref_count = len(not_built)
+ # Add this node to the waiting parents lists of
+ # anything we're waiting on, with a reference
+ # count so we can be put back on the list for
+ # re-evaluation when they've all finished.
+ node.ref_count = node.ref_count + child.add_to_waiting_parents(node)
+ if T: T.write(self.trace_message(' adjusted ref count: %s, child %s' %
+ (self.trace_node(node), repr(str(child)))))
- if S: S.not_built = S.not_built + 1
if T:
- c = map(str, not_built)
- c.sort()
- T.write(' waiting on unfinished children:\n %s\n' % c)
+ for pc in children_pending:
+ T.write(self.trace_message(' adding %s to the pending children set\n' %
+ self.trace_node(pc)))
+ self.pending_children = self.pending_children | children_pending
+
continue
- # Skip this node if it has side-effects that are currently being
- # built themselves or waiting for something else being built.
- side_effects = filter(lambda N:
- N.get_state() == SCons.Node.executing,
- node.side_effects)
- if side_effects:
- map(lambda n, P=node: n.add_to_waiting_s_e(P), side_effects)
+ # Skip this node if it has side-effects that are
+ # currently being built:
+ wait_side_effects = False
+ for se in executor.get_action_side_effects():
+ if se.get_state() == NODE_EXECUTING:
+ se.add_to_waiting_s_e(node)
+ wait_side_effects = True
+
+ if wait_side_effects:
if S: S.side_effects = S.side_effects + 1
- if T:
- c = map(str, side_effects)
- c.sort()
- T.write(' waiting on side effects:\n %s\n' % c)
continue
# The default when we've gotten through all of the checks above:
# this node is ready to be built.
if S: S.build = S.build + 1
- if T: T.write(' evaluating %s\n' % node)
+ if T: T.write(self.trace_message('Evaluating %s\n' %
+ self.trace_node(node)))
+
+ # For debugging only:
+ #
+ # try:
+ # self._validate_pending_children()
+ # except:
+ # self.ready_exc = sys.exc_info()
+ # return node
+
return node
return None
if node is None:
return None
- tlist = node.get_executor().targets
+ tlist = node.get_executor().get_all_targets()
- task = self.tasker(self, tlist, node is self.current_top, node)
+ task = self.tasker(self, tlist, node in self.original_top, node)
try:
task.make_ready()
- except KeyboardInterrupt:
- raise
except:
# We had a problem just trying to get this task ready (like
- # a child couldn't be linked in to a BuildDir when deciding
+ # a child couldn't be linked in to a VariantDir when deciding
# whether this node is current). Arrange to raise the
# exception when the Task is "executed."
self.ready_exc = sys.exc_info()
return task
+ def will_not_build(self, nodes, node_func=lambda n: None):
+ """
+ Perform clean-up about nodes that will never be built. Invokes
+ a user defined function on all of these nodes (including all
+ of their parents).
+ """
+
+ T = self.trace
+
+ pending_children = self.pending_children
+
+ to_visit = set(nodes)
+ pending_children = pending_children - to_visit
+
+ if T:
+ for n in nodes:
+ T.write(self.trace_message(' removing node %s from the pending children set\n' %
+ self.trace_node(n)))
+ try:
+ while True:
+ try:
+ node = to_visit.pop()
+ except AttributeError:
+ # Python 1.5.2
+ if len(to_visit):
+ node = to_visit[0]
+ to_visit.remove(node)
+ else:
+ break
+
+ node_func(node)
+
+ # Prune recursion by flushing the waiting children
+ # list immediately.
+ parents = node.waiting_parents
+ node.waiting_parents = set()
+
+ to_visit = to_visit | parents
+ pending_children = pending_children - parents
+
+ for p in parents:
+ p.ref_count = p.ref_count - 1
+ if T: T.write(self.trace_message(' removing parent %s from the pending children set\n' %
+ self.trace_node(p)))
+ except KeyError:
+ # The container to_visit has been emptied.
+ pass
+
+ # We have the stick back the pending_children list into the
+ # task master because the python 1.5.2 compatibility does not
+ # allow us to use in-place updates
+ self.pending_children = pending_children
+
def stop(self):
"""
Stops the current build completely.
"""
self.next_candidate = self.no_next_candidate
+
+ def cleanup(self):
+ """
+ Check for dependency cycles.
+ """
+ if not self.pending_children:
+ return
+
+ # TODO(1.5)
+ #nclist = [ (n, find_cycle([n], set())) for n in self.pending_children ]
+ nclist = [(n, find_cycle([n], set())) for n in self.pending_children]
+
+ # TODO(1.5)
+ #genuine_cycles = [
+ # node for node, cycle in nclist
+ # if cycle or node.get_state() != NODE_EXECUTED
+ #]
+ genuine_cycles = [t for t in nclist if t[1] or t[0].get_state() != NODE_EXECUTED]
+ if not genuine_cycles:
+ # All of the "cycles" found were single nodes in EXECUTED state,
+ # which is to say, they really weren't cycles. Just return.
+ return
+
+ desc = 'Found dependency cycle(s):\n'
+ for node, cycle in nclist:
+ if cycle:
+ desc = desc + " " + " -> ".join(map(str, cycle)) + "\n"
+ else:
+ desc = desc + \
+ " Internal Error: no cycle found for node %s (%s) in state %s\n" % \
+ (node, repr(node), StateString[node.get_state()])
+
+ raise SCons.Errors.UserError, desc
+
+# Local Variables:
+# tab-width:4
+# indent-tabs-mode:nil
+# End:
+# vim: set expandtab tabstop=4 shiftwidth=4:
projects / scons.git / blobdiff