ceph/src/boost/tools/build/src/tools/cast.py

   1 # Status: ported
   2 # Base revision: 64432.
   3 # Copyright 2005-2010 Vladimir Prus.
   4 # Distributed under the Boost Software License, Version 1.0. (See
   5 # accompanying file LICENSE_1_0.txt or copy at
   6 # http://www.boost.org/LICENSE_1_0.txt)
   7
   8 # Defines main target 'cast', used to change type for target. For example, in Qt
   9 # library one wants two kinds of CPP files -- those that just compiled and those
  10 # that are passed via the MOC tool.
  11 #
  12 # This is done with:
  13 #
  14 #    exe main : main.cpp [ cast _ moccable-cpp : widget.cpp ] ;
  15 #
  16 # Boost.Build will assign target type CPP to both main.cpp and widget.cpp. Then,
  17 # the cast rule will change target type of widget.cpp to MOCCABLE-CPP, and Qt
  18 # support will run the MOC tool as part of the build process.
  19 #
  20 # At the moment, the 'cast' rule only works for non-derived (source) targets.
  21 #
  22 # TODO: The following comment is unclear or incorrect. Clean it up.
  23 # > Another solution would be to add a separate main target 'moc-them' that
  24 # > would moc all the passed sources, no matter what their type is, but I prefer
  25 # > cast, as defining a new target type + generator for that type is somewhat
  26 # > simpler than defining a main target rule.
  27
  28 from b2.build import targets, virtual_target, property_set, type as type_
  29
  30 from b2.manager import get_manager
  31 from b2.util import bjam_signature, is_iterable_typed
  32
  33
  34 class CastTargetClass(targets.TypedTarget):
  35
  36     def construct(self, name, source_targets, ps):
  37         assert isinstance(name, basestring)
  38         assert is_iterable_typed(source_targets, virtual_target.VirtualTarget)
  39         assert isinstance(ps, property_set.PropertySet)
  40
  41         result = []
  42         for s in source_targets:
  43             if not isinstance(s, virtual_target.FileTarget):
  44                 get_manager().errors()("Source to the 'cast' metatager is not a file")
  45
  46             if s.action():
  47                 get_manager().errors()("Only non-derived targets allowed as sources for 'cast'.")
  48
  49
  50             r = s.clone_with_different_type(self.type())
  51             result.append(get_manager().virtual_targets().register(r))
  52
  53         return property_set.empty(), result
  54
  55
  56 @bjam_signature((["name", "type"], ["sources", "*"], ["requirements", "*"],
  57                  ["default_build", "*"], ["usage_requirements", "*"]))
  58 def cast(name, type, sources, requirements, default_build, usage_requirements):
  59
  60     from b2.manager import get_manager
  61     t = get_manager().targets()
  62
  63     project = get_manager().projects().current()
  64
  65     real_type = type_.type_from_rule_name(type)
  66     if not real_type:
  67         real_type = type
  68     return t.main_target_alternative(
  69         CastTargetClass(name, project, real_type,
  70                         t.main_target_sources(sources, name),
  71                         t.main_target_requirements(requirements, project),
  72                         t.main_target_default_build(default_build, project),
  73                         t.main_target_usage_requirements(usage_requirements, project)))
  74
  75
  76 get_manager().projects().add_rule("cast", cast)