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Last active Aug 29, 2015
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A meta build system for ninja. Called based on senpai/sempai.
#!/usr/bin/env python
"""Python module that generates .ninja files.
Some of the stuff here was borrowed from the main ninja project.
However this module aims to extend the bare-bones provided with a rich
python API.
Note: This file is meant to be a single file for easy inclusion for existing
build systems. Hence this file will be rather big.
import textwrap
import os, sys
import datetime
import fnmatch
import cStringIO as StringIO
except ImportError:
import io.StringIO as StringIO # python 3k compat
def escape_path(word):
return word.replace('$ ', '$$ ').replace(' ', '$ ').replace(':', '$:')
def escape(string):
"""Escape a string such that it can be embedded into a Ninja file without
further interpretation."""
assert '\n' not in string, 'Ninja syntax does not allow newlines'
# We only have one special metacharacter: '$'.
return string.replace('$', '$$')
class NinjaWriter(object):
def __init__(self, output, width=78):
self.output = output
self.width = width
def newline(self):
def comment(self, text):
for line in textwrap.wrap(text, self.width - 2):
self.output.write('# ' + line + '\n')
def variable(self, key, value, indent=0):
if value is None:
if isinstance(value, list):
value = ' '.join(filter(None, value)) # Filter out empty strings.
self._line('%s = %s' % (key, value), indent)
def pool(self, name, depth):
self._line('pool %s' % name)
self.variable('depth', depth, indent=1)
def rule(self, name, command, description=None, depfile=None,
generator=False, pool=None, restat=False, rspfile=None,
rspfile_content=None, deps=None):
self._line('rule %s' % name)
self.variable('command', command, indent=1)
if description:
self.variable('description', description, indent=1)
if depfile:
self.variable('depfile', depfile, indent=1)
if generator:
self.variable('generator', '1', indent=1)
if pool:
self.variable('pool', pool, indent=1)
if restat:
self.variable('restat', '1', indent=1)
if rspfile:
self.variable('rspfile', rspfile, indent=1)
if rspfile_content:
self.variable('rspfile_content', rspfile_content, indent=1)
if deps:
self.variable('deps', deps, indent=1)
def build(self, outputs, rule, inputs=None, implicit=None, order_only=None,
outputs = self._as_list(outputs)
out_outputs = [escape_path(x) for x in outputs]
all_inputs = [escape_path(x) for x in self._as_list(inputs)]
if implicit:
implicit = [escape_path(x) for x in self._as_list(implicit)]
if order_only:
order_only = [escape_path(x) for x in self._as_list(order_only)]
self._line('build %s: %s' % (' '.join(out_outputs),
' '.join([rule] + all_inputs)))
if variables:
if isinstance(variables, dict):
iterator = iter(variables.items())
iterator = iter(variables)
for key, val in iterator:
self.variable(key, val, indent=1)
return outputs
def include(self, path):
self._line('include %s' % path)
def subninja(self, path):
self._line('subninja %s' % path)
def default(self, paths):
self._line('default %s' % ' '.join(self._as_list(paths)))
def _count_dollars_before_index(self, s, i):
"""Returns the number of '$' characters right in front of s[i]."""
dollar_count = 0
dollar_index = i - 1
while dollar_index > 0 and s[dollar_index] == '$':
dollar_count += 1
dollar_index -= 1
return dollar_count
def _line(self, text, indent=0):
"""Write 'text' word-wrapped at self.width characters."""
leading_space = ' ' * indent
while len(leading_space) + len(text) > self.width:
# The text is too wide; wrap if possible.
# Find the rightmost space that would obey our width constraint and
# that's not an escaped space.
available_space = self.width - len(leading_space) - len(' $')
space = available_space
while True:
space = text.rfind(' ', 0, space)
if (space < 0 or
self._count_dollars_before_index(text, space) % 2 == 0):
if space < 0:
# No such space; just use the first unescaped space we can find.
space = available_space - 1
while True:
space = text.find(' ', space + 1)
if (space < 0 or
self._count_dollars_before_index(text, space) % 2 == 0):
if space < 0:
# Give up on breaking.
self.output.write(leading_space + text[0:space] + ' $\n')
text = text[space+1:]
# Subsequent lines are continuations, so indent them.
leading_space = ' ' * (indent+2)
self.output.write(leading_space + text + '\n')
def _as_list(self, input):
if input is None:
return []
if isinstance(input, list):
return input
return [input]
"""Represents the default compiler"""
class Compiler(object):
def __init__(self, name): = name
def rules(self, ninja):
ninja.rule('compile', command = '$cxx -MMD -MF $out.d -c $cxxflags $includes $depends $defines $in -o $out',
deps = 'gcc', depfile = '$out.d',
description = 'Compiling $in to $out')
ninja.rule('link', command = '$cxx $cxxflags $in -o $out $linkflags $libpath $libraries', description = 'Creating $out')
def object_file(self, filename):
(root, _) = os.path.splitext(filename)
return root + '.o'
def include(self, path):
return "-I\"{}\"".format(path)
def libpath(self, path):
return "-L\"{}\"".format(path)
def library(self, lib):
return "-l" + lib
def dependency(self, dep):
return "-isystem \"{}\"".format(dep)
def define(self, macro):
return "-D " + macro
def compiler(name):
if name == 'cl' or 'msvc' in name:
raise NotImplementedError('MSVC compilers are not supported yet')
return Compiler(name=name)
"""Represents the base class for all classes"""
class Options(object):
def __init__(self, *args, **kwargs):
self.flags = None
self.link_flags = None
self.libraries = None
self.library_paths = None
self.dependencies = None
self.includes = None
self.defines = None
"""Represents an executable to be made."""
class Executable(Options):
def __init__(self, name, **kwargs):
Options.__init__(self, kwargs) = name # the executable name
self.builddir = kwargs.get('builddir', None) # the executable specific output directory
self.objdir = kwargs.get('objdir', None) # the executable specific object directory = kwargs.get('target', None)
self.files = None = kwargs.get('run', None) # the name of the target that runs the executable
# monadic functions
def to_flags(flags):
if flags == None:
return None
return ' '.join(flags)
def fmap(function, iterable):
if iterable == None:
return None
return map(function, iterable)
# utility functions
def generate_files_from(directory, glob):
for root, directories, files in os.walk(directory):
for f in files:
if fnmatch.fnmatch(f, glob):
yield os.path.join(root, f)
def files_from(directory, glob):
return list(generate_files_from(directory, glob))
"""Represents a project. Usually only one is needed"""
class Project(Options):
def __init__(self, name, compiler, **kwargs):
Options.__init__(self, kwargs) = name
self.compiler = compiler
self.executables = []
self.sstream = StringIO.StringIO() = NinjaWriter(self.sstream)
self.builddir = kwargs.get('builddir', '.')
self.objdir = kwargs.get('objdir', '.')
def __create_variable_map(self, options):
return {
'cxxflags': to_flags(options.flags),
'includes': to_flags(fmap(self.compiler.include, options.includes)),
'depends': to_flags(fmap(self.compiler.dependency, options.dependencies)),
'defines': to_flags(fmap(self.compiler.define, options.defines)),
'linkflags': to_flags(options.link_flags),
'libpath': to_flags(fmap(self.compiler.libpath, options.library_paths)),
'libraries': to_flags(fmap(self.compiler.library, options.libraries))
def variables(self, **kwargs):
for k, v in kwargs.items():
if v == None:, ' ')
else:, v)
def add_executable(self, exe):
if not isinstance(exe, Executable):
raise ValueError("argument passed must be an 'Executable'")
def dump(self, stream, generator=True):
# create the global variables needed
today ="This file was generated automatically on {} using"
" the meta build system. Do not modify this.".format(today.isoformat(' ')))'ninja_required_version', '1.3')'cxx','builddir', self.builddir) # the project builddir
# process the global variables
project_variables = self.__create_variable_map(self)
# register the global rules
if generator == True:'bootstrap', command=' '.join(['python'] + sys.argv), generator=True), 'bootstrap', implicit=sys.argv[0])
# register the executables requested
for exe in self.executables:
if exe.files == None:
exe_variables = self.__create_variable_map(exe)
# compile the files in the project
object_files = []
objdir = exe.objdir if exe.objdir else self.objdir
for filename in exe.files:
obj = os.path.join(objdir, self.compiler.object_file(filename)), 'compile', inputs=filename, variables=exe_variables)
# final link step
builddir = exe.builddir if exe.builddir else self.builddir,, 'link', inputs=object_files, variables=exe_variables)
if != None:, 'phony', inputs=os.path.join(builddir,
# register the runner
if != None: + '_runner', command=os.path.join(builddir,, + '_runner',
# finalise the creation
result = self.sstream.getvalue()
self.sstream = StringIO.StringIO() = NinjaWriter(self.sstream)
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