"""SCons.Node The Node package for the SCons software construction utility. """ # # Copyright (c) 2001, 2002 Steven Knight # # Permission is hereby granted, free of charge, to any person obtaining # a copy of this software and associated documentation files (the # "Software"), to deal in the Software without restriction, including # without limitation the rights to use, copy, modify, merge, publish, # distribute, sublicense, and/or sell copies of the Software, and to # permit persons to whom the Software is furnished to do so, subject to # the following conditions: # # The above copyright notice and this permission notice shall be included # in all copies or substantial portions of the Software. # # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY # KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE # WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND # NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE # LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. # __revision__ = "src/engine/SCons/Node/__init__.py 0.D006 2002/03/28 02:47:47 software" import string import types import copy import sys from SCons.Errors import BuildError import SCons.Util # Node states # # These are in "priority" order, so that the maximum value for any # child/dependency of a node represents the state of that node if # it has no builder of its own. The canonical example is a file # system directory, which is only up to date if all of its children # were up to date. pending = 1 executing = 2 up_to_date = 3 executed = 4 failed = 5 class Node: """The base Node class, for entities that we know how to build, or use to build other Nodes. """ def __init__(self): self.sources = [] # source files used to build node self.depends = [] # explicit dependencies (from Depends) self.implicit = {} # implicit (scanned) dependencies self.ignore = [] # dependencies to ignore self.parents = {} self.wkids = None # Kids yet to walk, when it's an array self.builder = None self.scanner = None # explicit scanner from this node's Builder self.scanned = {} # cached scanned values self.src_scanners = {} # scanners for this node's source files self.env = None self.state = None self.bsig = None self.csig = None self.use_signature = 1 self.precious = None self.found_includes = {} def build(self): """Actually build the node. Return the status from the build.""" if not self.builder: return None try: # If this Builder instance has already been called, # there will already be an associated status. stat = self.builder.status except AttributeError: try: dict = copy.copy(self.env.Dictionary()) if hasattr(self, 'dir'): auto = self.env.autogenerate(dir = self.dir) else: auto = self.env.autogenerate() dict.update(auto) stat = self.builder.execute(env = dict, target = self, source = self.sources) except: raise BuildError(self, "Exception", sys.exc_type, sys.exc_value, sys.exc_traceback) if stat: raise BuildError(node = self, errstr = "Error %d" % stat) self.found_includes = {} # If we successfully build a node, then we need to rescan for # implicit dependencies, since it might have changed on us. self.scanned = {} return stat def builder_set(self, builder): self.builder = builder def builder_sig_adapter(self): """Create an adapter for calculating a builder's signature. The underlying signature class will call get_contents() to fetch the signature of a builder, but the actual content of that signature depends on the node and the environment (for construction variable substitution), so this adapter provides the right glue between the two. """ class Adapter: def __init__(self, node): self.node = node def get_contents(self): dict = self.node.env.Dictionary() dict.update(self.node.env.autogenerate()) try: dir = self.node.getcwd() except AttributeError: dir = None return self.node.builder.get_contents(env = dict) return Adapter(self) def scanner_set(self, scanner): self.scanner = scanner def src_scanner_set(self, key, scanner): self.src_scanners[key] = scanner def src_scanner_get(self, key): return self.src_scanners.get(key, None) def scan(self, scanner = None): if not scanner: scanner = self.scanner self.scanned[scanner] = 1 def scanner_key(self): return None def env_set(self, env, safe=0): if safe and self.env: return self.env = env def get_bsig(self): """Get the node's build signature (based on the signatures of its dependency files and build information).""" return self.bsig def set_bsig(self, bsig): """Set the node's build signature (based on the signatures of its dependency files and build information).""" self.bsig = bsig def get_csig(self): """Get the signature of the node's content.""" return self.csig def set_csig(self, csig): """Set the signature of the node's content.""" self.csig = csig def store_sigs(self): """Make the signatures permanent (that is, store them in the .sconsign file or equivalent).""" pass def set_precious(self, precious = 1): """Set the Node's precious value.""" self.precious = precious def prepare(self): """Prepare for this Node to be created: no-op by default.""" pass def add_dependency(self, depend): """Adds dependencies. The depend argument must be a list.""" self._add_child(self.depends, depend) def add_ignore(self, depend): """Adds dependencies to ignore. The depend argument must be a list.""" self._add_child(self.ignore, depend) def add_source(self, source): """Adds sources. The source argument must be a list.""" self._add_child(self.sources, source) def add_implicit(self, implicit, key): """Adds implicit (scanned) dependencies. The implicit argument must be a list.""" if not self.implicit.has_key(key): self.implicit[key] = [] self._add_child(self.implicit[key], implicit) def _add_child(self, collection, child): """Adds 'child' to 'collection'. The 'child' argument must be a list""" if type(child) is not type([]): raise TypeError("child must be a list") child = filter(lambda x, s=collection: x not in s, child) if child: collection.extend(child) for c in child: c.parents[self] = 1 def add_wkid(self, wkid): """Add a node to the list of kids waiting to be evaluated""" if self.wkids != None: self.wkids.append(wkid) def children(self, scanner): """Return a list of the node's direct children, minus those that are ignored by this node.""" return filter(lambda x, i=self.ignore: x not in i, self.all_children(scanner)) def all_children(self, scanner): """Return a list of all the node's direct children.""" #XXX Need to remove duplicates from this if not self.implicit.has_key(scanner): self.scan(scanner) if scanner: implicit = self.implicit[scanner] else: implicit = reduce(lambda x, y: x + y, self.implicit.values(), []) return self.sources + self.depends + implicit def get_parents(self): return self.parents.keys() def set_state(self, state): self.state = state def get_state(self): return self.state def current(self): return None def children_are_executed(self, scanner): return reduce(lambda x,y: ((y.get_state() == executed or y.get_state() == up_to_date) and x), self.children(scanner), 1) def get_children(node, parent): return node.children(None) def ignore_cycle(node, stack): pass def do_nothing(node, parent): pass class Walker: """An iterator for walking a Node tree. This is depth-first, children are visited before the parent. The Walker object can be initialized with any node, and returns the next node on the descent with each next() call. 'kids_func' is an optional function that will be called to get the children of a node instead of calling 'children'. 'cycle_func' is an optional function that will be called when a cycle is detected. This class does not get caught in node cycles caused, for example, by C header file include loops. """ def __init__(self, node, kids_func=get_children, cycle_func=ignore_cycle, eval_func=do_nothing): self.kids_func = kids_func self.cycle_func = cycle_func self.eval_func = eval_func node.wkids = copy.copy(kids_func(node, None)) self.stack = [node] self.history = {} # used to efficiently detect and avoid cycles self.history[node] = None def next(self): """Return the next node for this walk of the tree. This function is intentionally iterative, not recursive, to sidestep any issues of stack size limitations. """ while self.stack: if self.stack[-1].wkids: node = self.stack[-1].wkids.pop(0) if not self.stack[-1].wkids: self.stack[-1].wkids = None if self.history.has_key(node): self.cycle_func(node, self.stack) else: node.wkids = copy.copy(self.kids_func(node, self.stack[-1])) self.stack.append(node) self.history[node] = None else: node = self.stack.pop() del self.history[node] if node: if self.stack: parent = self.stack[-1] else: parent = None self.eval_func(node, parent) return node def is_done(self): return not self.stack arg2nodes_lookups = [] def arg2nodes(arg, node_factory=None): """This function converts a string or list into a list of Node instances. It follows the rules outlined in the SCons design document by accepting any of the following inputs: - A single string containing names separated by spaces. These will be split apart at the spaces. - A single Node instance, - A list containingg either strings or Node instances. Any strings in the list are not split at spaces. In all cases, the function returns a list of Node instances.""" narg = arg if SCons.Util.is_String(arg): narg = string.split(arg) elif not SCons.Util.is_List(arg): narg = [arg] nodes = [] for v in narg: if SCons.Util.is_String(v): n = None for l in arg2nodes_lookups: n = l(v) if not n is None: break if not n is None: nodes.append(n) elif node_factory: nodes.append(node_factory(v)) # Do we enforce the following restriction? Maybe, but it # would also restrict what we can do to allow people to # use the engine with alternate Node implementations... #elif not issubclass(v.__class__, Node): # raise TypeError else: nodes.append(v) return nodes