blob: 5c52ea23f854c9644e074b671980acb57b9aee84 [file] [log] [blame]
#!/usr/bin/python
"""Python module for generating .ninja files.
Note that this is emphatically not a required piece of Ninja; it's
just a helpful utility for build-file-generation systems that already
use Python.
"""
import re
import textwrap
def escape_path(word):
return word.replace('$ ', '$$ ').replace(' ', '$ ').replace(':', '$:')
class Writer(object):
def __init__(self, output, width=78):
self.output = output
self.width = width
def newline(self):
self.output.write('\n')
def comment(self, text, has_path=False):
for line in textwrap.wrap(text, self.width - 2, break_long_words=False,
break_on_hyphens=False):
self.output.write('# ' + line + '\n')
def variable(self, key, value, indent=0):
if value is None:
return
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,
variables=None, implicit_outputs=None):
outputs = as_list(outputs)
out_outputs = [escape_path(x) for x in outputs]
all_inputs = [escape_path(x) for x in as_list(inputs)]
if implicit:
implicit = [escape_path(x) for x in as_list(implicit)]
all_inputs.append('|')
all_inputs.extend(implicit)
if order_only:
order_only = [escape_path(x) for x in as_list(order_only)]
all_inputs.append('||')
all_inputs.extend(order_only)
if implicit_outputs:
implicit_outputs = [escape_path(x)
for x in as_list(implicit_outputs)]
out_outputs.append('|')
out_outputs.extend(implicit_outputs)
self._line('build %s: %s' % (' '.join(out_outputs),
' '.join([rule] + all_inputs)))
if variables:
if isinstance(variables, dict):
iterator = iter(variables.items())
else:
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(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):
break
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):
break
if space < 0:
# Give up on breaking.
break
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 close(self):
self.output.close()
def as_list(input):
if input is None:
return []
if isinstance(input, list):
return input
return [input]
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('$', '$$')
def expand(string, vars, local_vars={}):
"""Expand a string containing $vars as Ninja would.
Note: doesn't handle the full Ninja variable syntax, but it's enough
to make configure.py's use of it work.
"""
def exp(m):
var = m.group(1)
if var == '$':
return '$'
return local_vars.get(var, vars.get(var, ''))
return re.sub(r'\$(\$|\w*)', exp, string)