summaryrefslogtreecommitdiffstats
path: root/src/engine/SCons/Executor.py
blob: 8151f87d1c0af50230c4b192305463fe40cd2ba7 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
"""SCons.Executor

A module for executing actions with specific lists of target and source
Nodes.

"""

#
# __COPYRIGHT__
#
# 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__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"


from SCons.Debug import logInstanceCreation
import SCons.Util


class Executor:
    """A class for controlling instances of executing an action.

    This largely exists to hold a single association of a builder,
    environment, environment overrides, targets and sources for later
    processing as needed.
    """

    def __init__(self, builder, env, overrides, targets, sources):
        if __debug__: logInstanceCreation(self)
        self.builder = builder
        self.env = env
        self.overrides = overrides
        self.targets = targets
        self.sources = sources[:]

    def get_build_env(self):
        """Fetch or create the appropriate build Environment
        for this Executor.
        """
        try:
            return self.build_env
        except AttributeError:
            if self.env is None:
                # There was no Environment specifically associated with
                # this set of targets (which kind of implies that it
                # is--or they are--source files, but who knows...).
                # So use the environment associated with the Builder
                # itself.
                env = self.builder.env
            else:
                # The normal case:  use the Environment that was
                # used to specify how these targets will be built.
                env = self.env
            overrides = {}
            overrides.update(self.builder.overrides)
            overrides.update(self.overrides)
            try:
                generate_build_dict = self.targets[0].generate_build_dict
            except AttributeError:
                pass
            else:
                overrides.update(generate_build_dict())
            overrides.update(SCons.Util.subst_dict(self.targets, self.sources))
            self.build_env = env.Override(overrides)
            return self.build_env

    def get_action_list(self, target):
        """Fetch or create the appropriate action list (for this target).

        There is an architectural mistake here: we cache the action list
        for the Executor and re-use it regardless of which target is
        being asked for.  In practice, this doesn't seem to be a problem
        because executing the action list will update all of the targets
        involved, so only one target's pre- and post-actions will win,
        anyway.  This is probably a bug we should fix...
        """
        try:
            al = self.action_list
        except AttributeError:
            al = self.builder.action.get_actions()
            self.action_list = al
        # XXX shouldn't reach into node attributes like this
        return target.pre_actions + al + target.post_actions

    def __call__(self, target, func):
        """Actually execute the action list."""
        action_list = self.get_action_list(target)
        if not action_list:
            return
        env = self.get_build_env()
        for action in action_list:
            func(action, self.targets, self.sources, env)

    def cleanup(self):
        try:
            del self.build_env
        except AttributeError:
            pass

    def add_sources(self, sources):
        """Add source files to this Executor's list.  This is necessary
        for "multi" Builders that can be called repeatedly to build up
        a source file list for a given target."""
        slist = filter(lambda x, s=self.sources: x not in s, sources)
        self.sources.extend(slist)

    def get_raw_contents(self):
        """Fetch the raw signature contents.  This, along with
        get_contents(), is the real reason this class exists, so we can
        compute this once and cache it regardless of how many target or
        source Nodes there are.
        """
        try:
            return self.raw_contents
        except AttributeError:
            action = self.builder.action
            self.raw_contents = action.get_raw_contents(self.targets,
                                                        self.sources,
                                                        self.get_build_env())
            return self.raw_contents

    def get_contents(self):
        """Fetch the signature contents.  This, along with
        get_raw_contents(), is the real reason this class exists, so we
        can compute this once and cache it regardless of how many target
        or source Nodes there are.
        """
        try:
            return self.contents
        except AttributeError:
            action = self.builder.action
            self.contents = action.get_contents(self.targets,
                                                self.sources,
                                                self.get_build_env())
            return self.contents

    def get_timestamp(self):
        """Fetch a time stamp for this Executor.  We don't have one, of
        course (only files do), but this is the interface used by the
        timestamp module.
        """
        return 0