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Diffstat (limited to 'waflib/TaskGen.py')
| -rw-r--r-- | waflib/TaskGen.py | 917 |
1 files changed, 917 insertions, 0 deletions
diff --git a/waflib/TaskGen.py b/waflib/TaskGen.py new file mode 100644 index 0000000..532b7d5 --- /dev/null +++ b/waflib/TaskGen.py @@ -0,0 +1,917 @@ +#!/usr/bin/env python +# encoding: utf-8 +# Thomas Nagy, 2005-2018 (ita) + +""" +Task generators + +The class :py:class:`waflib.TaskGen.task_gen` encapsulates the creation of task objects (low-level code) +The instances can have various parameters, but the creation of task nodes (Task.py) +is deferred. To achieve this, various methods are called from the method "apply" +""" + +import copy, re, os, functools +from waflib import Task, Utils, Logs, Errors, ConfigSet, Node + +feats = Utils.defaultdict(set) +"""remember the methods declaring features""" + +HEADER_EXTS = ['.h', '.hpp', '.hxx', '.hh'] + +class task_gen(object): + """ + Instances of this class create :py:class:`waflib.Task.Task` when + calling the method :py:meth:`waflib.TaskGen.task_gen.post` from the main thread. + A few notes: + + * The methods to call (*self.meths*) can be specified dynamically (removing, adding, ..) + * The 'features' are used to add methods to self.meths and then execute them + * The attribute 'path' is a node representing the location of the task generator + * The tasks created are added to the attribute *tasks* + * The attribute 'idx' is a counter of task generators in the same path + """ + + mappings = Utils.ordered_iter_dict() + """Mappings are global file extension mappings that are retrieved in the order of definition""" + + prec = Utils.defaultdict(set) + """Dict that holds the precedence execution rules for task generator methods""" + + def __init__(self, *k, **kw): + """ + Task generator objects predefine various attributes (source, target) for possible + processing by process_rule (make-like rules) or process_source (extensions, misc methods) + + Tasks are stored on the attribute 'tasks'. They are created by calling methods + listed in ``self.meths`` or referenced in the attribute ``features`` + A topological sort is performed to execute the methods in correct order. + + The extra key/value elements passed in ``kw`` are set as attributes + """ + self.source = [] + self.target = '' + + self.meths = [] + """ + List of method names to execute (internal) + """ + + self.features = [] + """ + List of feature names for bringing new methods in + """ + + self.tasks = [] + """ + Tasks created are added to this list + """ + + if not 'bld' in kw: + # task generators without a build context :-/ + self.env = ConfigSet.ConfigSet() + self.idx = 0 + self.path = None + else: + self.bld = kw['bld'] + self.env = self.bld.env.derive() + self.path = kw.get('path', self.bld.path) # by default, emulate chdir when reading scripts + + # Provide a unique index per folder + # This is part of a measure to prevent output file name collisions + path = self.path.abspath() + try: + self.idx = self.bld.idx[path] = self.bld.idx.get(path, 0) + 1 + except AttributeError: + self.bld.idx = {} + self.idx = self.bld.idx[path] = 1 + + # Record the global task generator count + try: + self.tg_idx_count = self.bld.tg_idx_count = self.bld.tg_idx_count + 1 + except AttributeError: + self.tg_idx_count = self.bld.tg_idx_count = 1 + + for key, val in kw.items(): + setattr(self, key, val) + + def __str__(self): + """Debugging helper""" + return "<task_gen %r declared in %s>" % (self.name, self.path.abspath()) + + def __repr__(self): + """Debugging helper""" + lst = [] + for x in self.__dict__: + if x not in ('env', 'bld', 'compiled_tasks', 'tasks'): + lst.append("%s=%s" % (x, repr(getattr(self, x)))) + return "bld(%s) in %s" % (", ".join(lst), self.path.abspath()) + + def get_cwd(self): + """ + Current working directory for the task generator, defaults to the build directory. + This is still used in a few places but it should disappear at some point as the classes + define their own working directory. + + :rtype: :py:class:`waflib.Node.Node` + """ + return self.bld.bldnode + + def get_name(self): + """ + If the attribute ``name`` is not set on the instance, + the name is computed from the target name:: + + def build(bld): + x = bld(name='foo') + x.get_name() # foo + y = bld(target='bar') + y.get_name() # bar + + :rtype: string + :return: name of this task generator + """ + try: + return self._name + except AttributeError: + if isinstance(self.target, list): + lst = [str(x) for x in self.target] + name = self._name = ','.join(lst) + else: + name = self._name = str(self.target) + return name + def set_name(self, name): + self._name = name + + name = property(get_name, set_name) + + def to_list(self, val): + """ + Ensures that a parameter is a list, see :py:func:`waflib.Utils.to_list` + + :type val: string or list of string + :param val: input to return as a list + :rtype: list + """ + if isinstance(val, str): + return val.split() + else: + return val + + def post(self): + """ + Creates tasks for this task generators. The following operations are performed: + + #. The body of this method is called only once and sets the attribute ``posted`` + #. The attribute ``features`` is used to add more methods in ``self.meths`` + #. The methods are sorted by the precedence table ``self.prec`` or `:waflib:attr:waflib.TaskGen.task_gen.prec` + #. The methods are then executed in order + #. The tasks created are added to :py:attr:`waflib.TaskGen.task_gen.tasks` + """ + if getattr(self, 'posted', None): + return False + self.posted = True + + keys = set(self.meths) + keys.update(feats['*']) + + # add the methods listed in the features + self.features = Utils.to_list(self.features) + for x in self.features: + st = feats[x] + if st: + keys.update(st) + elif not x in Task.classes: + Logs.warn('feature %r does not exist - bind at least one method to it?', x) + + # copy the precedence table + prec = {} + prec_tbl = self.prec + for x in prec_tbl: + if x in keys: + prec[x] = prec_tbl[x] + + # elements disconnected + tmp = [] + for a in keys: + for x in prec.values(): + if a in x: + break + else: + tmp.append(a) + + tmp.sort(reverse=True) + + # topological sort + out = [] + while tmp: + e = tmp.pop() + if e in keys: + out.append(e) + try: + nlst = prec[e] + except KeyError: + pass + else: + del prec[e] + for x in nlst: + for y in prec: + if x in prec[y]: + break + else: + tmp.append(x) + tmp.sort(reverse=True) + + if prec: + buf = ['Cycle detected in the method execution:'] + for k, v in prec.items(): + buf.append('- %s after %s' % (k, [x for x in v if x in prec])) + raise Errors.WafError('\n'.join(buf)) + self.meths = out + + # then we run the methods in order + Logs.debug('task_gen: posting %s %d', self, id(self)) + for x in out: + try: + v = getattr(self, x) + except AttributeError: + raise Errors.WafError('%r is not a valid task generator method' % x) + Logs.debug('task_gen: -> %s (%d)', x, id(self)) + v() + + Logs.debug('task_gen: posted %s', self.name) + return True + + def get_hook(self, node): + """ + Returns the ``@extension`` method to call for a Node of a particular extension. + + :param node: Input file to process + :type node: :py:class:`waflib.Tools.Node.Node` + :return: A method able to process the input node by looking at the extension + :rtype: function + """ + name = node.name + for k in self.mappings: + try: + if name.endswith(k): + return self.mappings[k] + except TypeError: + # regexps objects + if k.match(name): + return self.mappings[k] + keys = list(self.mappings.keys()) + raise Errors.WafError("File %r has no mapping in %r (load a waf tool?)" % (node, keys)) + + def create_task(self, name, src=None, tgt=None, **kw): + """ + Creates task instances. + + :param name: task class name + :type name: string + :param src: input nodes + :type src: list of :py:class:`waflib.Tools.Node.Node` + :param tgt: output nodes + :type tgt: list of :py:class:`waflib.Tools.Node.Node` + :return: A task object + :rtype: :py:class:`waflib.Task.Task` + """ + task = Task.classes[name](env=self.env.derive(), generator=self) + if src: + task.set_inputs(src) + if tgt: + task.set_outputs(tgt) + task.__dict__.update(kw) + self.tasks.append(task) + return task + + def clone(self, env): + """ + Makes a copy of a task generator. Once the copy is made, it is necessary to ensure that the + it does not create the same output files as the original, or the same files may + be compiled several times. + + :param env: A configuration set + :type env: :py:class:`waflib.ConfigSet.ConfigSet` + :return: A copy + :rtype: :py:class:`waflib.TaskGen.task_gen` + """ + newobj = self.bld() + for x in self.__dict__: + if x in ('env', 'bld'): + continue + elif x in ('path', 'features'): + setattr(newobj, x, getattr(self, x)) + else: + setattr(newobj, x, copy.copy(getattr(self, x))) + + newobj.posted = False + if isinstance(env, str): + newobj.env = self.bld.all_envs[env].derive() + else: + newobj.env = env.derive() + + return newobj + +def declare_chain(name='', rule=None, reentrant=None, color='BLUE', + ext_in=[], ext_out=[], before=[], after=[], decider=None, scan=None, install_path=None, shell=False): + """ + Creates a new mapping and a task class for processing files by extension. + See Tools/flex.py for an example. + + :param name: name for the task class + :type name: string + :param rule: function to execute or string to be compiled in a function + :type rule: string or function + :param reentrant: re-inject the output file in the process (done automatically, set to 0 to disable) + :type reentrant: int + :param color: color for the task output + :type color: string + :param ext_in: execute the task only after the files of such extensions are created + :type ext_in: list of string + :param ext_out: execute the task only before files of such extensions are processed + :type ext_out: list of string + :param before: execute instances of this task before classes of the given names + :type before: list of string + :param after: execute instances of this task after classes of the given names + :type after: list of string + :param decider: if present, function that returns a list of output file extensions (overrides ext_out for output files, but not for the build order) + :type decider: function + :param scan: scanner function for the task + :type scan: function + :param install_path: installation path for the output nodes + :type install_path: string + """ + ext_in = Utils.to_list(ext_in) + ext_out = Utils.to_list(ext_out) + if not name: + name = rule + cls = Task.task_factory(name, rule, color=color, ext_in=ext_in, ext_out=ext_out, before=before, after=after, scan=scan, shell=shell) + + def x_file(self, node): + if ext_in: + _ext_in = ext_in[0] + + tsk = self.create_task(name, node) + cnt = 0 + + ext = decider(self, node) if decider else cls.ext_out + for x in ext: + k = node.change_ext(x, ext_in=_ext_in) + tsk.outputs.append(k) + + if reentrant != None: + if cnt < int(reentrant): + self.source.append(k) + else: + # reinject downstream files into the build + for y in self.mappings: # ~ nfile * nextensions :-/ + if k.name.endswith(y): + self.source.append(k) + break + cnt += 1 + + if install_path: + self.install_task = self.add_install_files(install_to=install_path, install_from=tsk.outputs) + return tsk + + for x in cls.ext_in: + task_gen.mappings[x] = x_file + return x_file + +def taskgen_method(func): + """ + Decorator that registers method as a task generator method. + The function must accept a task generator as first parameter:: + + from waflib.TaskGen import taskgen_method + @taskgen_method + def mymethod(self): + pass + + :param func: task generator method to add + :type func: function + :rtype: function + """ + setattr(task_gen, func.__name__, func) + return func + +def feature(*k): + """ + Decorator that registers a task generator method that will be executed when the + object attribute ``feature`` contains the corresponding key(s):: + + from waflib.Task import feature + @feature('myfeature') + def myfunction(self): + print('that is my feature!') + def build(bld): + bld(features='myfeature') + + :param k: feature names + :type k: list of string + """ + def deco(func): + setattr(task_gen, func.__name__, func) + for name in k: + feats[name].update([func.__name__]) + return func + return deco + +def before_method(*k): + """ + Decorator that registera task generator method which will be executed + before the functions of given name(s):: + + from waflib.TaskGen import feature, before + @feature('myfeature') + @before_method('fun2') + def fun1(self): + print('feature 1!') + @feature('myfeature') + def fun2(self): + print('feature 2!') + def build(bld): + bld(features='myfeature') + + :param k: method names + :type k: list of string + """ + def deco(func): + setattr(task_gen, func.__name__, func) + for fun_name in k: + task_gen.prec[func.__name__].add(fun_name) + return func + return deco +before = before_method + +def after_method(*k): + """ + Decorator that registers a task generator method which will be executed + after the functions of given name(s):: + + from waflib.TaskGen import feature, after + @feature('myfeature') + @after_method('fun2') + def fun1(self): + print('feature 1!') + @feature('myfeature') + def fun2(self): + print('feature 2!') + def build(bld): + bld(features='myfeature') + + :param k: method names + :type k: list of string + """ + def deco(func): + setattr(task_gen, func.__name__, func) + for fun_name in k: + task_gen.prec[fun_name].add(func.__name__) + return func + return deco +after = after_method + +def extension(*k): + """ + Decorator that registers a task generator method which will be invoked during + the processing of source files for the extension given:: + + from waflib import Task + class mytask(Task): + run_str = 'cp ${SRC} ${TGT}' + @extension('.moo') + def create_maa_file(self, node): + self.create_task('mytask', node, node.change_ext('.maa')) + def build(bld): + bld(source='foo.moo') + """ + def deco(func): + setattr(task_gen, func.__name__, func) + for x in k: + task_gen.mappings[x] = func + return func + return deco + +@taskgen_method +def to_nodes(self, lst, path=None): + """ + Flatten the input list of string/nodes/lists into a list of nodes. + + It is used by :py:func:`waflib.TaskGen.process_source` and :py:func:`waflib.TaskGen.process_rule`. + It is designed for source files, for folders, see :py:func:`waflib.Tools.ccroot.to_incnodes`: + + :param lst: input list + :type lst: list of string and nodes + :param path: path from which to search the nodes (by default, :py:attr:`waflib.TaskGen.task_gen.path`) + :type path: :py:class:`waflib.Tools.Node.Node` + :rtype: list of :py:class:`waflib.Tools.Node.Node` + """ + tmp = [] + path = path or self.path + find = path.find_resource + + if isinstance(lst, Node.Node): + lst = [lst] + + for x in Utils.to_list(lst): + if isinstance(x, str): + node = find(x) + elif hasattr(x, 'name'): + node = x + else: + tmp.extend(self.to_nodes(x)) + continue + if not node: + raise Errors.WafError('source not found: %r in %r' % (x, self)) + tmp.append(node) + return tmp + +@feature('*') +def process_source(self): + """ + Processes each element in the attribute ``source`` by extension. + + #. The *source* list is converted through :py:meth:`waflib.TaskGen.to_nodes` to a list of :py:class:`waflib.Node.Node` first. + #. File extensions are mapped to methods having the signature: ``def meth(self, node)`` by :py:meth:`waflib.TaskGen.extension` + #. The method is retrieved through :py:meth:`waflib.TaskGen.task_gen.get_hook` + #. When called, the methods may modify self.source to append more source to process + #. The mappings can map an extension or a filename (see the code below) + """ + self.source = self.to_nodes(getattr(self, 'source', [])) + for node in self.source: + self.get_hook(node)(self, node) + +@feature('*') +@before_method('process_source') +def process_rule(self): + """ + Processes the attribute ``rule``. When present, :py:meth:`waflib.TaskGen.process_source` is disabled:: + + def build(bld): + bld(rule='cp ${SRC} ${TGT}', source='wscript', target='bar.txt') + + Main attributes processed: + + * rule: command to execute, it can be a tuple of strings for multiple commands + * chmod: permissions for the resulting files (integer value such as Utils.O755) + * shell: set to False to execute the command directly (default is True to use a shell) + * scan: scanner function + * vars: list of variables to trigger rebuilds, such as CFLAGS + * cls_str: string to display when executing the task + * cls_keyword: label to display when executing the task + * cache_rule: by default, try to re-use similar classes, set to False to disable + * source: list of Node or string objects representing the source files required by this task + * target: list of Node or string objects representing the files that this task creates + * cwd: current working directory (Node or string) + * stdout: standard output, set to None to prevent waf from capturing the text + * stderr: standard error, set to None to prevent waf from capturing the text + * timeout: timeout for command execution (Python 3) + * always: whether to always run the command (False by default) + * deep_inputs: whether the task must depend on the input file tasks too (False by default) + """ + if not getattr(self, 'rule', None): + return + + # create the task class + name = str(getattr(self, 'name', None) or self.target or getattr(self.rule, '__name__', self.rule)) + + # or we can put the class in a cache for performance reasons + try: + cache = self.bld.cache_rule_attr + except AttributeError: + cache = self.bld.cache_rule_attr = {} + + chmod = getattr(self, 'chmod', None) + shell = getattr(self, 'shell', True) + color = getattr(self, 'color', 'BLUE') + scan = getattr(self, 'scan', None) + _vars = getattr(self, 'vars', []) + cls_str = getattr(self, 'cls_str', None) + cls_keyword = getattr(self, 'cls_keyword', None) + use_cache = getattr(self, 'cache_rule', 'True') + deep_inputs = getattr(self, 'deep_inputs', False) + + scan_val = has_deps = hasattr(self, 'deps') + if scan: + scan_val = id(scan) + + key = Utils.h_list((name, self.rule, chmod, shell, color, cls_str, cls_keyword, scan_val, _vars, deep_inputs)) + + cls = None + if use_cache: + try: + cls = cache[key] + except KeyError: + pass + if not cls: + rule = self.rule + if chmod is not None: + def chmod_fun(tsk): + for x in tsk.outputs: + os.chmod(x.abspath(), tsk.generator.chmod) + if isinstance(rule, tuple): + rule = list(rule) + rule.append(chmod_fun) + rule = tuple(rule) + else: + rule = (rule, chmod_fun) + + cls = Task.task_factory(name, rule, _vars, shell=shell, color=color) + + if cls_str: + setattr(cls, '__str__', self.cls_str) + + if cls_keyword: + setattr(cls, 'keyword', self.cls_keyword) + + if deep_inputs: + Task.deep_inputs(cls) + + if scan: + cls.scan = self.scan + elif has_deps: + def scan(self): + nodes = [] + for x in self.generator.to_list(getattr(self.generator, 'deps', None)): + node = self.generator.path.find_resource(x) + if not node: + self.generator.bld.fatal('Could not find %r (was it declared?)' % x) + nodes.append(node) + return [nodes, []] + cls.scan = scan + + if use_cache: + cache[key] = cls + + # now create one instance + tsk = self.create_task(name) + + for x in ('after', 'before', 'ext_in', 'ext_out'): + setattr(tsk, x, getattr(self, x, [])) + + if hasattr(self, 'stdout'): + tsk.stdout = self.stdout + + if hasattr(self, 'stderr'): + tsk.stderr = self.stderr + + if getattr(self, 'timeout', None): + tsk.timeout = self.timeout + + if getattr(self, 'always', None): + tsk.always_run = True + + if getattr(self, 'target', None): + if isinstance(self.target, str): + self.target = self.target.split() + if not isinstance(self.target, list): + self.target = [self.target] + for x in self.target: + if isinstance(x, str): + tsk.outputs.append(self.path.find_or_declare(x)) + else: + x.parent.mkdir() # if a node was given, create the required folders + tsk.outputs.append(x) + if getattr(self, 'install_path', None): + self.install_task = self.add_install_files(install_to=self.install_path, + install_from=tsk.outputs, chmod=getattr(self, 'chmod', Utils.O644)) + + if getattr(self, 'source', None): + tsk.inputs = self.to_nodes(self.source) + # bypass the execution of process_source by setting the source to an empty list + self.source = [] + + if getattr(self, 'cwd', None): + tsk.cwd = self.cwd + + if isinstance(tsk.run, functools.partial): + # Python documentation says: "partial objects defined in classes + # behave like static methods and do not transform into bound + # methods during instance attribute look-up." + tsk.run = functools.partial(tsk.run, tsk) + +@feature('seq') +def sequence_order(self): + """ + Adds a strict sequential constraint between the tasks generated by task generators. + It works because task generators are posted in order. + It will not post objects which belong to other folders. + + Example:: + + bld(features='javac seq') + bld(features='jar seq') + + To start a new sequence, set the attribute seq_start, for example:: + + obj = bld(features='seq') + obj.seq_start = True + + Note that the method is executed in last position. This is more an + example than a widely-used solution. + """ + if self.meths and self.meths[-1] != 'sequence_order': + self.meths.append('sequence_order') + return + + if getattr(self, 'seq_start', None): + return + + # all the tasks previously declared must be run before these + if getattr(self.bld, 'prev', None): + self.bld.prev.post() + for x in self.bld.prev.tasks: + for y in self.tasks: + y.set_run_after(x) + + self.bld.prev = self + + +re_m4 = re.compile(r'@(\w+)@', re.M) + +class subst_pc(Task.Task): + """ + Creates *.pc* files from *.pc.in*. The task is executed whenever an input variable used + in the substitution changes. + """ + + def force_permissions(self): + "Private for the time being, we will probably refactor this into run_str=[run1,chmod]" + if getattr(self.generator, 'chmod', None): + for x in self.outputs: + os.chmod(x.abspath(), self.generator.chmod) + + def run(self): + "Substitutes variables in a .in file" + + if getattr(self.generator, 'is_copy', None): + for i, x in enumerate(self.outputs): + x.write(self.inputs[i].read('rb'), 'wb') + stat = os.stat(self.inputs[i].abspath()) # Preserve mtime of the copy + os.utime(self.outputs[i].abspath(), (stat.st_atime, stat.st_mtime)) + self.force_permissions() + return None + + if getattr(self.generator, 'fun', None): + ret = self.generator.fun(self) + if not ret: + self.force_permissions() + return ret + + code = self.inputs[0].read(encoding=getattr(self.generator, 'encoding', 'latin-1')) + if getattr(self.generator, 'subst_fun', None): + code = self.generator.subst_fun(self, code) + if code is not None: + self.outputs[0].write(code, encoding=getattr(self.generator, 'encoding', 'latin-1')) + self.force_permissions() + return None + + # replace all % by %% to prevent errors by % signs + code = code.replace('%', '%%') + + # extract the vars foo into lst and replace @foo@ by %(foo)s + lst = [] + def repl(match): + g = match.group + if g(1): + lst.append(g(1)) + return "%%(%s)s" % g(1) + return '' + code = getattr(self.generator, 're_m4', re_m4).sub(repl, code) + + try: + d = self.generator.dct + except AttributeError: + d = {} + for x in lst: + tmp = getattr(self.generator, x, '') or self.env[x] or self.env[x.upper()] + try: + tmp = ''.join(tmp) + except TypeError: + tmp = str(tmp) + d[x] = tmp + + code = code % d + self.outputs[0].write(code, encoding=getattr(self.generator, 'encoding', 'latin-1')) + self.generator.bld.raw_deps[self.uid()] = lst + + # make sure the signature is updated + try: + delattr(self, 'cache_sig') + except AttributeError: + pass + + self.force_permissions() + + def sig_vars(self): + """ + Compute a hash (signature) of the variables used in the substitution + """ + bld = self.generator.bld + env = self.env + upd = self.m.update + + if getattr(self.generator, 'fun', None): + upd(Utils.h_fun(self.generator.fun).encode()) + if getattr(self.generator, 'subst_fun', None): + upd(Utils.h_fun(self.generator.subst_fun).encode()) + + # raw_deps: persistent custom values returned by the scanner + vars = self.generator.bld.raw_deps.get(self.uid(), []) + + # hash both env vars and task generator attributes + act_sig = bld.hash_env_vars(env, vars) + upd(act_sig) + + lst = [getattr(self.generator, x, '') for x in vars] + upd(Utils.h_list(lst)) + + return self.m.digest() + +@extension('.pc.in') +def add_pcfile(self, node): + """ + Processes *.pc.in* files to *.pc*. Installs the results to ``${PREFIX}/lib/pkgconfig/`` by default + + def build(bld): + bld(source='foo.pc.in', install_path='${LIBDIR}/pkgconfig/') + """ + tsk = self.create_task('subst_pc', node, node.change_ext('.pc', '.pc.in')) + self.install_task = self.add_install_files( + install_to=getattr(self, 'install_path', '${LIBDIR}/pkgconfig/'), install_from=tsk.outputs) + +class subst(subst_pc): + pass + +@feature('subst') +@before_method('process_source', 'process_rule') +def process_subst(self): + """ + Defines a transformation that substitutes the contents of *source* files to *target* files:: + + def build(bld): + bld( + features='subst', + source='foo.c.in', + target='foo.c', + install_path='${LIBDIR}/pkgconfig', + VAR = 'val' + ) + + The input files are supposed to contain macros of the form *@VAR@*, where *VAR* is an argument + of the task generator object. + + This method overrides the processing by :py:meth:`waflib.TaskGen.process_source`. + """ + + src = Utils.to_list(getattr(self, 'source', [])) + if isinstance(src, Node.Node): + src = [src] + tgt = Utils.to_list(getattr(self, 'target', [])) + if isinstance(tgt, Node.Node): + tgt = [tgt] + if len(src) != len(tgt): + raise Errors.WafError('invalid number of source/target for %r' % self) + + for x, y in zip(src, tgt): + if not x or not y: + raise Errors.WafError('null source or target for %r' % self) + a, b = None, None + + if isinstance(x, str) and isinstance(y, str) and x == y: + a = self.path.find_node(x) + b = self.path.get_bld().make_node(y) + if not os.path.isfile(b.abspath()): + b.parent.mkdir() + else: + if isinstance(x, str): + a = self.path.find_resource(x) + elif isinstance(x, Node.Node): + a = x + if isinstance(y, str): + b = self.path.find_or_declare(y) + elif isinstance(y, Node.Node): + b = y + + if not a: + raise Errors.WafError('could not find %r for %r' % (x, self)) + + tsk = self.create_task('subst', a, b) + for k in ('after', 'before', 'ext_in', 'ext_out'): + val = getattr(self, k, None) + if val: + setattr(tsk, k, val) + + # paranoid safety measure for the general case foo.in->foo.h with ambiguous dependencies + for xt in HEADER_EXTS: + if b.name.endswith(xt): + tsk.ext_in = tsk.ext_in + ['.h'] + break + + inst_to = getattr(self, 'install_path', None) + if inst_to: + self.install_task = self.add_install_files(install_to=inst_to, + install_from=b, chmod=getattr(self, 'chmod', Utils.O644)) + + self.source = [] + |