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Diffstat (limited to 'jam-files/boost-build/build/generators.py')
| -rw-r--r-- | jam-files/boost-build/build/generators.py | 1089 |
1 files changed, 1089 insertions, 0 deletions
diff --git a/jam-files/boost-build/build/generators.py b/jam-files/boost-build/build/generators.py new file mode 100644 index 00000000..2c59f7ca --- /dev/null +++ b/jam-files/boost-build/build/generators.py @@ -0,0 +1,1089 @@ +# Status: being ported by Vladimir Prus +# Base revision: 48649 +# TODO: replace the logging with dout + +# Copyright Vladimir Prus 2002. +# Copyright Rene Rivera 2006. +# +# Distributed under the Boost Software License, Version 1.0. +# (See accompanying file LICENSE_1_0.txt or copy at +# http://www.boost.org/LICENSE_1_0.txt) + +# Manages 'generators' --- objects which can do transformation between different +# target types and contain algorithm for finding transformation from sources +# to targets. +# +# The main entry point to this module is generators.construct rule. It is given +# a list of source targets, desired target type and a set of properties. +# It starts by selecting 'viable generators', which have any chances of producing +# the desired target type with the required properties. Generators are ranked and +# a set of most specific ones is selected. +# +# The most specific generators have their 'run' methods called, with the properties +# and list of sources. Each one selects target which can be directly consumed, and +# tries to convert the remaining ones to the types it can consume. This is done +# by recursively calling 'construct' with all consumable types. +# +# If the generator has collected all the targets it needs, it creates targets +# corresponding to result, and returns it. When all generators have been run, +# results of one of them are selected and returned as result. +# +# It's quite possible that 'construct' returns more targets that it was asked for. +# For example, it was asked to target type EXE, but the only found generators produces +# both EXE and TDS (file with debug) information. The extra target will be returned. +# +# Likewise, when generator tries to convert sources to consumable types, it can get +# more targets that it was asked for. The question is what to do with extra targets. +# Boost.Build attempts to convert them to requested types, and attempts as early as +# possible. Specifically, this is done after invoking each generator. (Later I'll +# document the rationale for trying extra target conversion at that point). +# +# That early conversion is not always desirable. Suppose a generator got a source of +# type Y and must consume one target of type X_1 and one target of type X_2. +# When converting Y to X_1 extra target of type Y_2 is created. We should not try to +# convert it to type X_1, because if we do so, the generator will get two targets +# of type X_1, and will be at loss as to which one to use. Because of that, the +# 'construct' rule has a parameter, telling if multiple targets can be returned. If +# the parameter is false, conversion of extra targets is not performed. + + +import re +import cStringIO +import os.path + +from virtual_target import Subvariant +import virtual_target, type, property_set, property +from b2.util.logger import * +from b2.util.utility import * +from b2.util import set +from b2.util.sequence import unique +import b2.util.sequence as sequence +from b2.manager import get_manager +import b2.build.type + +def reset (): + """ Clear the module state. This is mainly for testing purposes. + """ + global __generators, __type_to_generators, __generators_for_toolset, __construct_stack + global __overrides, __active_generators + global __viable_generators_cache, __viable_source_types_cache + global __vstg_cached_generators, __vst_cached_types + + __generators = {} + __type_to_generators = {} + __generators_for_toolset = {} + __overrides = {} + + # TODO: can these be global? + __construct_stack = [] + __viable_generators_cache = {} + __viable_source_types_cache = {} + __active_generators = [] + + __vstg_cached_generators = [] + __vst_cached_types = [] + +reset () + +_re_separate_types_prefix_and_postfix = re.compile ('([^\\(]*)(\\((.*)%(.*)\\))?') +_re_match_type = re.compile('([^\\(]*)(\\(.*\\))?') + + +__debug = None +__indent = "" + +def debug(): + global __debug + if __debug is None: + __debug = "--debug-generators" in bjam.variable("ARGV") + return __debug + +def increase_indent(): + global __indent + __indent += " " + +def decrease_indent(): + global __indent + __indent = __indent[0:-4] + + +# Updated cached viable source target type information as needed after a new +# derived target type gets added. This is needed because if a target type is a +# viable source target type for some generator then all of the target type's +# derived target types are automatically viable as source target types for the +# same generator. Does nothing if a non-derived target type is passed to it. +# +def update_cached_information_with_a_new_type(type): + + base_type = b2.build.type.base(type) + + if base_type: + for g in __vstg_cached_generators: + if base_type in __viable_source_types_cache.get(g, []): + __viable_source_types_cache[g].append(type) + + for t in __vst_cached_types: + if base_type in __viable_source_types_cache.get(t, []): + __viable_source_types_cache[t].append(type) + +# Clears cached viable source target type information except for target types +# and generators with all source types listed as viable. Should be called when +# something invalidates those cached values by possibly causing some new source +# types to become viable. +# +def invalidate_extendable_viable_source_target_type_cache(): + + global __vstg_cached_generators + generators_with_cached_source_types = __vstg_cached_generators + __vstg_cached_generators = [] + + for g in generators_with_cached_source_types: + if __viable_source_types_cache.has_key(g): + if __viable_source_types_cache[g] == ["*"]: + __vstg_cached_generators.append(g) + else: + del __viable_source_types_cache[g] + + global __vst_cached_types + types_with_cached_sources_types = __vst_cached_types + __vst_cached_types = [] + for t in types_with_cached_sources_types: + if __viable_source_types_cache.has_key(t): + if __viable_source_types_cache[t] == ["*"]: + __vst_cached_types.append(t) + else: + del __viable_source_types_cache[t] + +def dout(message): + if debug(): + print __indent + message + +class Generator: + """ Creates a generator. + manager: the build manager. + id: identifies the generator + + rule: the rule which sets up build actions. + + composing: whether generator processes each source target in + turn, converting it to required types. + Ordinary generators pass all sources together to + recusrive generators.construct_types call. + + source_types (optional): types that this generator can handle + + target_types_and_names: types the generator will create and, optionally, names for + created targets. Each element should have the form + type["(" name-pattern ")"] + for example, obj(%_x). Name of generated target will be found + by replacing % with the name of source, provided explicit name + was not specified. + + requirements (optional) + + NOTE: all subclasses must have a similar signature for clone to work! + """ + def __init__ (self, id, composing, source_types, target_types_and_names, requirements = []): + assert(not isinstance(source_types, str)) + assert(not isinstance(target_types_and_names, str)) + self.id_ = id + self.composing_ = composing + self.source_types_ = source_types + self.target_types_and_names_ = target_types_and_names + self.requirements_ = requirements + + self.target_types_ = [] + self.name_prefix_ = [] + self.name_postfix_ = [] + + for e in target_types_and_names: + # Create three parallel lists: one with the list of target types, + # and two other with prefixes and postfixes to be added to target + # name. We use parallel lists for prefix and postfix (as opposed + # to mapping), because given target type might occur several times, + # for example "H H(%_symbols)". + m = _re_separate_types_prefix_and_postfix.match (e) + + if not m: + raise BaseException ("Invalid type and name '%s' in declaration of type '%s'" % (e, id)) + + target_type = m.group (1) + if not target_type: target_type = '' + prefix = m.group (3) + if not prefix: prefix = '' + postfix = m.group (4) + if not postfix: postfix = '' + + self.target_types_.append (target_type) + self.name_prefix_.append (prefix) + self.name_postfix_.append (postfix) + + for x in self.source_types_: + type.validate (x) + + for x in self.target_types_: + type.validate (x) + + def clone (self, new_id, new_toolset_properties): + """ Returns another generator which differers from $(self) in + - id + - value to <toolset> feature in properties + """ + return self.__class__ (new_id, + self.composing_, + self.source_types_, + self.target_types_and_names_, + # Note: this does not remove any subfeatures of <toolset> + # which might cause problems + property.change (self.requirements_, '<toolset>') + new_toolset_properties) + + def clone_and_change_target_type(self, base, type): + """Creates another generator that is the same as $(self), except that + if 'base' is in target types of $(self), 'type' will in target types + of the new generator.""" + target_types = [] + for t in self.target_types_and_names_: + m = _re_match_type.match(t) + assert m + + if m.group(1) == base: + if m.group(2): + target_types.append(type + m.group(2)) + else: + target_types.append(type) + else: + target_types.append(t) + + return self.__class__(self.id_, self.composing_, + self.source_types_, + target_types, + self.requirements_) + + + def id(self): + return self.id_ + + def source_types (self): + """ Returns the list of target type the generator accepts. + """ + return self.source_types_ + + def target_types (self): + """ Returns the list of target types that this generator produces. + It is assumed to be always the same -- i.e. it cannot change depending + list of sources. + """ + return self.target_types_ + + def requirements (self): + """ Returns the required properties for this generator. Properties + in returned set must be present in build properties if this + generator is to be used. If result has grist-only element, + that build properties must include some value of that feature. + """ + return self.requirements_ + + def match_rank (self, ps): + """ Returns true if the generator can be run with the specified + properties. + """ + # See if generator's requirements are satisfied by + # 'properties'. Treat a feature name in requirements + # (i.e. grist-only element), as matching any value of the + # feature. + all_requirements = self.requirements () + + property_requirements = [] + feature_requirements = [] + # This uses strings because genenator requirements allow + # the '<feature>' syntax without value and regular validation + # is not happy about that. + for r in all_requirements: + if get_value (r): + property_requirements.append (r) + + else: + feature_requirements.append (r) + + return all(ps.get(get_grist(s)) == [get_value(s)] for s in property_requirements) \ + and all(ps.get(get_grist(s)) for s in feature_requirements) + + def run (self, project, name, prop_set, sources): + """ Tries to invoke this generator on the given sources. Returns a + list of generated targets (instances of 'virtual-target'). + + project: Project for which the targets are generated. + + name: Determines the name of 'name' attribute for + all generated targets. See 'generated_targets' method. + + prop_set: Desired properties for generated targets. + + sources: Source targets. + """ + + if project.manager ().logger ().on (): + project.manager ().logger ().log (__name__, " generator '%s'" % self.id_) + project.manager ().logger ().log (__name__, " composing: '%s'" % self.composing_) + + if not self.composing_ and len (sources) > 1 and len (self.source_types_) > 1: + raise BaseException ("Unsupported source/source_type combination") + + # We don't run composing generators if no name is specified. The reason + # is that composing generator combines several targets, which can have + # different names, and it cannot decide which name to give for produced + # target. Therefore, the name must be passed. + # + # This in effect, means that composing generators are runnable only + # at top-level of transofrmation graph, or if name is passed explicitly. + # Thus, we dissallow composing generators in the middle. For example, the + # transofrmation CPP -> OBJ -> STATIC_LIB -> RSP -> EXE won't be allowed + # (the OBJ -> STATIC_LIB generator is composing) + if not self.composing_ or name: + return self.run_really (project, name, prop_set, sources) + else: + return [] + + def run_really (self, project, name, prop_set, sources): + + # consumed: Targets that this generator will consume directly. + # bypassed: Targets that can't be consumed and will be returned as-is. + + if self.composing_: + (consumed, bypassed) = self.convert_multiple_sources_to_consumable_types (project, prop_set, sources) + else: + (consumed, bypassed) = self.convert_to_consumable_types (project, name, prop_set, sources) + + result = [] + if consumed: + result = self.construct_result (consumed, project, name, prop_set) + result.extend (bypassed) + + if result: + if project.manager ().logger ().on (): + project.manager ().logger ().log (__name__, " SUCCESS: ", result) + + else: + project.manager ().logger ().log (__name__, " FAILURE") + + return result + + def construct_result (self, consumed, project, name, prop_set): + """ Constructs the dependency graph that will be returned by this + generator. + consumed: Already prepared list of consumable targets + If generator requires several source files will contain + exactly len $(self.source_types_) targets with matching types + Otherwise, might contain several targets with the type of + self.source_types_ [0] + project: + name: + prop_set: Properties to be used for all actions create here + """ + result = [] + # If this is 1->1 transformation, apply it to all consumed targets in order. + if len (self.source_types_) < 2 and not self.composing_: + + for r in consumed: + result.extend (self.generated_targets ([r], prop_set, project, name)) + + else: + + if consumed: + result.extend (self.generated_targets (consumed, prop_set, project, name)) + + return result + + def determine_target_name(self, fullname): + # Determine target name from fullname (maybe including path components) + # Place optional prefix and postfix around basename + + dir = os.path.dirname(fullname) + name = os.path.basename(fullname) + + if dir and not ".." in dir and not os.path.isabs(dir): + # Relative path is always relative to the source + # directory. Retain it, so that users can have files + # with the same in two different subdirectories. + name = dir + "/" + name + + return name + + def determine_output_name(self, sources): + """Determine the name of the produced target from the + names of the sources.""" + + # The simple case if when a name + # of source has single dot. Then, we take the part before + # dot. Several dots can be caused by: + # - Using source file like a.host.cpp + # - A type which suffix has a dot. Say, we can + # type 'host_cpp' with extension 'host.cpp'. + # In the first case, we want to take the part till the last + # dot. In the second case -- no sure, but for now take + # the part till the last dot too. + name = os.path.splitext(sources[0].name())[0] + + for s in sources[1:]: + n2 = os.path.splitext(s.name()) + if n2 != name: + get_manager().errors()( + "%s: source targets have different names: cannot determine target name" + % (self.id_)) + + # Names of sources might include directory. We should strip it. + return self.determine_target_name(sources[0].name()) + + + def generated_targets (self, sources, prop_set, project, name): + """ Constructs targets that are created after consuming 'sources'. + The result will be the list of virtual-target, which the same length + as 'target_types' attribute and with corresponding types. + + When 'name' is empty, all source targets must have the same value of + the 'name' attribute, which will be used instead of the 'name' argument. + + The value of 'name' attribute for each generated target will be equal to + the 'name' parameter if there's no name pattern for this type. Otherwise, + the '%' symbol in the name pattern will be replaced with the 'name' parameter + to obtain the 'name' attribute. + + For example, if targets types are T1 and T2(with name pattern "%_x"), suffixes + for T1 and T2 are .t1 and t2, and source if foo.z, then created files would + be "foo.t1" and "foo_x.t2". The 'name' attribute actually determined the + basename of a file. + + Note that this pattern mechanism has nothing to do with implicit patterns + in make. It's a way to produce target which name is different for name of + source. + """ + if not name: + name = self.determine_output_name(sources) + + # Assign an action for each target + action = self.action_class() + a = action(project.manager(), sources, self.id_, prop_set) + + # Create generated target for each target type. + targets = [] + pre = self.name_prefix_ + post = self.name_postfix_ + for t in self.target_types_: + basename = os.path.basename(name) + idx = basename.find(".") + if idx != -1: + basename = basename[:idx] + generated_name = pre[0] + basename + post[0] + generated_name = os.path.join(os.path.dirname(name), generated_name) + pre = pre[1:] + post = post[1:] + + targets.append(virtual_target.FileTarget(generated_name, t, project, a)) + + return [ project.manager().virtual_targets().register(t) for t in targets ] + + def convert_to_consumable_types (self, project, name, prop_set, sources, only_one=False): + """ Attempts to convert 'source' to the types that this generator can + handle. The intention is to produce the set of targets can should be + used when generator is run. + only_one: convert 'source' to only one of source types + if there's more that one possibility, report an + error. + + Returns a pair: + consumed: all targets that can be consumed. + bypassed: all targets that cannot be consumed. + """ + consumed = [] + bypassed = [] + missing_types = [] + + if len (sources) > 1: + # Don't know how to handle several sources yet. Just try + # to pass the request to other generator + missing_types = self.source_types_ + + else: + (c, m) = self.consume_directly (sources [0]) + consumed += c + missing_types += m + + # No need to search for transformation if + # some source type has consumed source and + # no more source types are needed. + if only_one and consumed: + missing_types = [] + + #TODO: we should check that only one source type + #if create of 'only_one' is true. + # TODO: consider if consuned/bypassed separation should + # be done by 'construct_types'. + + if missing_types: + transformed = construct_types (project, name, missing_types, prop_set, sources) + + # Add targets of right type to 'consumed'. Add others to + # 'bypassed'. The 'generators.construct' rule has done + # its best to convert everything to the required type. + # There's no need to rerun it on targets of different types. + + # NOTE: ignoring usage requirements + for t in transformed[1]: + if t.type() in missing_types: + consumed.append(t) + + else: + bypassed.append(t) + + consumed = unique(consumed) + bypassed = unique(bypassed) + + # remove elements of 'bypassed' that are in 'consumed' + + # Suppose the target type of current generator, X is produced from + # X_1 and X_2, which are produced from Y by one generator. + # When creating X_1 from Y, X_2 will be added to 'bypassed' + # Likewise, when creating X_2 from Y, X_1 will be added to 'bypassed' + # But they are also in 'consumed'. We have to remove them from + # bypassed, so that generators up the call stack don't try to convert + # them. + + # In this particular case, X_1 instance in 'consumed' and X_1 instance + # in 'bypassed' will be the same: because they have the same source and + # action name, and 'virtual-target.register' won't allow two different + # instances. Therefore, it's OK to use 'set.difference'. + + bypassed = set.difference(bypassed, consumed) + + return (consumed, bypassed) + + + def convert_multiple_sources_to_consumable_types (self, project, prop_set, sources): + """ Converts several files to consumable types. + """ + consumed = [] + bypassed = [] + + # We process each source one-by-one, trying to convert it to + # a usable type. + for s in sources: + # TODO: need to check for failure on each source. + (c, b) = self.convert_to_consumable_types (project, None, prop_set, [s], True) + if not c: + project.manager ().logger ().log (__name__, " failed to convert ", s) + + consumed.extend (c) + bypassed.extend (b) + + return (consumed, bypassed) + + def consume_directly (self, source): + real_source_type = source.type () + + # If there are no source types, we can consume anything + source_types = self.source_types() + if not source_types: + source_types = [real_source_type] + + consumed = [] + missing_types = [] + for st in source_types: + # The 'source' if of right type already) + if real_source_type == st or type.is_derived (real_source_type, st): + consumed.append (source) + + else: + missing_types.append (st) + + return (consumed, missing_types) + + def action_class (self): + """ Returns the class to be used to actions. Default implementation + returns "action". + """ + return virtual_target.Action + + +def find (id): + """ Finds the generator with id. Returns None if not found. + """ + return __generators.get (id, None) + +def register (g): + """ Registers new generator instance 'g'. + """ + id = g.id() + + __generators [id] = g + + # A generator can produce several targets of the + # same type. We want unique occurence of that generator + # in .generators.$(t) in that case, otherwise, it will + # be tried twice and we'll get false ambiguity. + for t in sequence.unique(g.target_types()): + __type_to_generators.setdefault(t, []).append(g) + + # Update the set of generators for toolset + + # TODO: should we check that generator with this id + # is not already registered. For example, the fop.jam + # module intentionally declared two generators with the + # same id, so such check will break it. + + # Some generators have multiple periods in their name, so the + # normal $(id:S=) won't generate the right toolset name. + # e.g. if id = gcc.compile.c++, then + # .generators-for-toolset.$(id:S=) will append to + # .generators-for-toolset.gcc.compile, which is a separate + # value from .generators-for-toolset.gcc. Correcting this + # makes generator inheritance work properly. + # See also inherit-generators in module toolset + base = id.split ('.', 100) [0] + + __generators_for_toolset.setdefault(base, []).append(g) + + # After adding a new generator that can construct new target types, we need + # to clear the related cached viable source target type information for + # constructing a specific target type or using a specific generator. Cached + # viable source target type lists affected by this are those containing any + # of the target types constructed by the new generator or any of their base + # target types. + # + # A more advanced alternative to clearing that cached viable source target + # type information would be to expand it with additional source types or + # even better - mark it as needing to be expanded on next use. + # + # For now we just clear all the cached viable source target type information + # that does not simply state 'all types' and may implement a more detailed + # algorithm later on if it becomes needed. + + invalidate_extendable_viable_source_target_type_cache() + + +def register_standard (id, source_types, target_types, requirements = []): + """ Creates new instance of the 'generator' class and registers it. + Returns the creates instance. + Rationale: the instance is returned so that it's possible to first register + a generator and then call 'run' method on that generator, bypassing all + generator selection. + """ + g = Generator (id, False, source_types, target_types, requirements) + register (g) + return g + +def register_composing (id, source_types, target_types, requirements = []): + g = Generator (id, True, source_types, target_types, requirements) + register (g) + return g + +def generators_for_toolset (toolset): + """ Returns all generators which belong to 'toolset'. + """ + return __generators_for_toolset.get(toolset, []) + +def override (overrider_id, overridee_id): + """Make generator 'overrider-id' be preferred to + 'overridee-id'. If, when searching for generators + that could produce a target of certain type, + both those generators are amoung viable generators, + the overridden generator is immediately discarded. + + The overridden generators are discarded immediately + after computing the list of viable generators, before + running any of them.""" + + __overrides.get(overrider_id, []).append(overridee_id) + +def __viable_source_types_real (target_type): + """ Returns a list of source type which can possibly be converted + to 'target_type' by some chain of generator invocation. + + More formally, takes all generators for 'target_type' and + returns union of source types for those generators and result + of calling itself recusrively on source types. + """ + generators = [] + + # 't0' is the initial list of target types we need to process to get a list + # of their viable source target types. New target types will not be added to + # this list. + t0 = type.all_bases (target_type) + + + # 't' is the list of target types which have not yet been processed to get a + # list of their viable source target types. This list will get expanded as + # we locate more target types to process. + t = t0 + + result = [] + while t: + # Find all generators for current type. + # Unlike 'find_viable_generators' we don't care about prop_set. + generators = __type_to_generators.get (t [0], []) + t = t[1:] + + for g in generators: + if not g.source_types(): + # Empty source types -- everything can be accepted + result = "*" + # This will terminate outer loop. + t = None + break + + for source_type in g.source_types (): + if not source_type in result: + # If generator accepts 'source_type' it + # will happily accept any type derived from it + all = type.all_derived (source_type) + for n in all: + if not n in result: + + # Here there is no point in adding target types to + # the list of types to process in case they are or + # have already been on that list. We optimize this + # check by realizing that we only need to avoid the + # original target type's base types. Other target + # types that are or have been on the list of target + # types to process have been added to the 'result' + # list as well and have thus already been eliminated + # by the previous if. + if not n in t0: + t.append (n) + result.append (n) + + return result + + +def viable_source_types (target_type): + """ Helper rule, caches the result of '__viable_source_types_real'. + """ + if not __viable_source_types_cache.has_key(target_type): + __vst_cached_types.append(target_type) + __viable_source_types_cache [target_type] = __viable_source_types_real (target_type) + return __viable_source_types_cache [target_type] + +def viable_source_types_for_generator_real (generator): + """ Returns the list of source types, which, when passed to 'run' + method of 'generator', has some change of being eventually used + (probably after conversion by other generators) + """ + source_types = generator.source_types () + + if not source_types: + # If generator does not specify any source types, + # it might be special generator like builtin.lib-generator + # which just relays to other generators. Return '*' to + # indicate that any source type is possibly OK, since we don't + # know for sure. + return ['*'] + + else: + result = [] + for s in source_types: + viable_sources = viable_source_types(s) + if viable_sources == "*": + result = ["*"] + break + else: + result.extend(type.all_derived(s) + viable_sources) + return unique(result) + +def viable_source_types_for_generator (generator): + """ Caches the result of 'viable_source_types_for_generator'. + """ + if not __viable_source_types_cache.has_key(generator): + __vstg_cached_generators.append(generator) + __viable_source_types_cache[generator] = viable_source_types_for_generator_real (generator) + + return __viable_source_types_cache[generator] + +def try_one_generator_really (project, name, generator, target_type, properties, sources): + """ Returns usage requirements + list of created targets. + """ + targets = generator.run (project, name, properties, sources) + + usage_requirements = [] + success = False + + dout("returned " + str(targets)) + + if targets: + success = True; + + if isinstance (targets[0], property_set.PropertySet): + usage_requirements = targets [0] + targets = targets [1] + + else: + usage_requirements = property_set.empty () + + dout( " generator" + generator.id() + " spawned ") + # generators.dout [ indent ] " " $(targets) ; +# if $(usage-requirements) +# { +# generators.dout [ indent ] " with usage requirements:" $(x) ; +# } + + if success: + return (usage_requirements, targets) + else: + return None + +def try_one_generator (project, name, generator, target_type, properties, sources): + """ Checks if generator invocation can be pruned, because it's guaranteed + to fail. If so, quickly returns empty list. Otherwise, calls + try_one_generator_really. + """ + source_types = [] + + for s in sources: + source_types.append (s.type ()) + + viable_source_types = viable_source_types_for_generator (generator) + + if source_types and viable_source_types != ['*'] and\ + not set.intersection (source_types, viable_source_types): + if project.manager ().logger ().on (): + id = generator.id () + project.manager ().logger ().log (__name__, "generator '%s' pruned" % id) + project.manager ().logger ().log (__name__, "source_types" '%s' % source_types) + project.manager ().logger ().log (__name__, "viable_source_types '%s'" % viable_source_types) + + return [] + + else: + return try_one_generator_really (project, name, generator, target_type, properties, sources) + + +def construct_types (project, name, target_types, prop_set, sources): + + result = [] + usage_requirements = property_set.empty() + + for t in target_types: + r = construct (project, name, t, prop_set, sources) + + if r: + (ur, targets) = r + usage_requirements = usage_requirements.add(ur) + result.extend(targets) + + # TODO: have to introduce parameter controlling if + # several types can be matched and add appropriate + # checks + + # TODO: need to review the documentation for + # 'construct' to see if it should return $(source) even + # if nothing can be done with it. Currents docs seem to + # imply that, contrary to the behaviour. + if result: + return (usage_requirements, result) + + else: + return (usage_requirements, sources) + +def __ensure_type (targets): + """ Ensures all 'targets' have types. If this is not so, exists with + error. + """ + for t in targets: + if not t.type (): + get_manager().errors()("target '%s' has no type" % str (t)) + +def find_viable_generators_aux (target_type, prop_set): + """ Returns generators which can be used to construct target of specified type + with specified properties. Uses the following algorithm: + - iterates over requested target_type and all it's bases (in the order returned bt + type.all-bases. + - for each type find all generators that generate that type and which requirements + are satisfied by properties. + - if the set of generators is not empty, returns that set. + + Note: this algorithm explicitly ignores generators for base classes if there's + at least one generator for requested target_type. + """ + # Select generators that can create the required target type. + viable_generators = [] + initial_generators = [] + + import type + + # Try all-type generators first. Assume they have + # quite specific requirements. + all_bases = type.all_bases(target_type) + + for t in all_bases: + + initial_generators = __type_to_generators.get(t, []) + + if initial_generators: + dout("there are generators for this type") + if t != target_type: + # We're here, when no generators for target-type are found, + # but there are some generators for a base type. + # We'll try to use them, but they will produce targets of + # base type, not of 'target-type'. So, we clone the generators + # and modify the list of target types. + generators2 = [] + for g in initial_generators[:]: + # generators.register adds generator to the list of generators + # for toolsets, which is a bit strange, but should work. + # That list is only used when inheriting toolset, which + # should have being done before generators are run. + ng = g.clone_and_change_target_type(t, target_type) + generators2.append(ng) + register(ng) + + initial_generators = generators2 + break + + for g in initial_generators: + dout("trying generator " + g.id() + + "(" + str(g.source_types()) + "->" + str(g.target_types()) + ")") + + m = g.match_rank(prop_set) + if m: + dout(" is viable") + viable_generators.append(g) + + return viable_generators + +def find_viable_generators (target_type, prop_set): + key = target_type + '.' + str (prop_set) + + l = __viable_generators_cache.get (key, None) + if not l: + l = [] + + if not l: + l = find_viable_generators_aux (target_type, prop_set) + + __viable_generators_cache [key] = l + + viable_generators = [] + for g in l: + # Avoid trying the same generator twice on different levels. + # TODO: is this really used? + if not g in __active_generators: + viable_generators.append (g) + else: + dout(" generator %s is active, discarding" % g.id()) + + # Generators which override 'all'. + all_overrides = [] + + # Generators which are overriden + overriden_ids = [] + + for g in viable_generators: + id = g.id () + + this_overrides = __overrides.get (id, []) + + if this_overrides: + overriden_ids.extend (this_overrides) + if 'all' in this_overrides: + all_overrides.append (g) + + if all_overrides: + viable_generators = all_overrides + + result = [] + for g in viable_generators: + if not g.id () in overriden_ids: + result.append (g) + + + return result + +def __construct_really (project, name, target_type, prop_set, sources): + """ Attempts to construct target by finding viable generators, running them + and selecting the dependency graph. + """ + viable_generators = find_viable_generators (target_type, prop_set) + + result = [] + + project.manager ().logger ().log (__name__, "*** %d viable generators" % len (viable_generators)) + + generators_that_succeeded = [] + + for g in viable_generators: + __active_generators.append(g) + r = try_one_generator (project, name, g, target_type, prop_set, sources) + del __active_generators[-1] + + if r: + generators_that_succeeded.append(g) + if result: + output = cStringIO.StringIO() + print >>output, "ambiguity found when searching for best transformation" + print >>output, "Trying to produce type '%s' from: " % (target_type) + for s in sources: + print >>output, " - " + s.str() + print >>output, "Generators that succeeded:" + for g in generators_that_succeeded: + print >>output, " - " + g.id() + print >>output, "First generator produced: " + for t in result[1:]: + print >>output, " - " + str(t) + print >>output, "Second generator produced:" + for t in r[1:]: + print >>output, " - " + str(t) + get_manager().errors()(output.getvalue()) + else: + result = r; + + return result; + + +def construct (project, name, target_type, prop_set, sources, top_level=False): + """ Attempts to create target of 'target-type' with 'properties' + from 'sources'. The 'sources' are treated as a collection of + *possible* ingridients -- i.e. it is not required to consume + them all. If 'multiple' is true, the rule is allowed to return + several targets of 'target-type'. + + Returns a list of target. When this invocation is first instance of + 'construct' in stack, returns only targets of requested 'target-type', + otherwise, returns also unused sources and additionally generated + targets. + + If 'top-level' is set, does not suppress generators that are already + used in the stack. This may be useful in cases where a generator + has to build a metatarget -- for example a target corresponding to + built tool. + """ + + global __active_generators + if top_level: + saved_active = __active_generators + __active_generators = [] + + global __construct_stack + if not __construct_stack: + __ensure_type (sources) + + __construct_stack.append (1) + + if project.manager().logger().on(): + increase_indent () + + dout( "*** construct " + target_type) + + for s in sources: + dout(" from " + str(s)) + + project.manager().logger().log (__name__, " properties: ", prop_set.raw ()) + + result = __construct_really(project, name, target_type, prop_set, sources) + + project.manager().logger().decrease_indent() + + __construct_stack = __construct_stack [1:] + + if top_level: + __active_generators = saved_active + + return result + |