metaparse/tools/string_headers.py
2017-04-20 16:35:06 +02:00

348 lines
10 KiB
Python
Executable File

#!/usr/bin/python
"""Utility to generate the header files for BOOST_METAPARSE_STRING"""
# Copyright Abel Sinkovics (abel@sinkovics.hu) 2016.
# Distributed under the Boost Software License, Version 1.0.
# (See accompanying file LICENSE_1_0.txt or copy at
# http://www.boost.org/LICENSE_1_0.txt)
import argparse
import math
import os
import sys
VERSION = 1
class Namespace(object):
"""Generate namespace definition"""
def __init__(self, out_f, names):
self.out_f = out_f
self.names = names
def begin(self):
"""Generate the beginning part"""
self.out_f.write('\n')
for depth, name in enumerate(self.names):
self.out_f.write(
'{0}namespace {1}\n{0}{{\n'.format(self.prefix(depth), name)
)
def end(self):
"""Generate the closing part"""
for depth in xrange(len(self.names) - 1, -1, -1):
self.out_f.write('{0}}}\n'.format(self.prefix(depth)))
def prefix(self, depth=None):
"""Returns the prefix of a given depth. Returns the prefix code inside
the namespace should use when depth is None."""
if depth is None:
depth = len(self.names)
return ' ' * depth
def __enter__(self):
self.begin()
return self
def __exit__(self, typ, value, traceback):
self.end()
def write_autogen_info(out_f):
"""Write the comment about the file being autogenerated"""
out_f.write(
'\n'
'// This is an automatically generated header file.\n'
'// Generated with the tools/string_headers.py utility of\n'
'// Boost.Metaparse\n'
)
class IncludeGuard(object):
"""Generate include guards"""
def __init__(self, out_f):
self.out_f = out_f
def begin(self):
"""Generate the beginning part"""
name = 'BOOST_METAPARSE_V1_CPP11_IMPL_STRING_HPP'
self.out_f.write('#ifndef {0}\n#define {0}\n'.format(name))
write_autogen_info(self.out_f)
def end(self):
"""Generate the closing part"""
self.out_f.write('\n#endif\n')
def __enter__(self):
self.begin()
return self
def __exit__(self, typ, value, traceback):
self.end()
def macro_name(name):
"""Generate the full macro name"""
return 'BOOST_METAPARSE_V{0}_{1}'.format(VERSION, name)
def define_macro(out_f, (name, args, body), undefine=False, check=True):
"""Generate a macro definition or undefinition"""
if undefine:
out_f.write(
'#undef {0}\n'
.format(macro_name(name))
)
else:
if args:
arg_list = '({0})'.format(', '.join(args))
else:
arg_list = ''
if check:
out_f.write(
'#ifdef {0}\n'
'# error {0} already defined.\n'
'#endif\n'
.format(macro_name(name))
)
out_f.write(
'#define {0}{1} {2}\n'.format(macro_name(name), arg_list, body)
)
def filename(out_dir, name, undefine=False):
"""Generate the filename"""
if undefine:
prefix = 'undef_'
else:
prefix = ''
return os.path.join(out_dir, '{0}{1}.hpp'.format(prefix, name.lower()))
def length_limits(max_length_limit, length_limit_step):
"""Generates the length limits"""
string_len = len(str(max_length_limit))
return [
str(i).zfill(string_len) for i in
xrange(
length_limit_step,
max_length_limit + length_limit_step - 1,
length_limit_step
)
]
def unique_names(count):
"""Generate count unique variable name"""
return ('C{0}'.format(i) for i in xrange(0, count))
def generate_take(out_f, steps, line_prefix):
"""Generate the take function"""
out_f.write(
'{0}constexpr inline int take(int n_)\n'
'{0}{{\n'
'{0} return {1} 0 {2};\n'
'{0}}}\n'
'\n'.format(
line_prefix,
''.join('n_ >= {0} ? {0} : ('.format(s) for s in steps),
')' * len(steps)
)
)
def generate_make_string(out_f, max_step):
"""Generate the make_string template"""
steps = [2 ** n for n in xrange(int(math.log(max_step, 2)), -1, -1)]
with Namespace(
out_f,
['boost', 'metaparse', 'v{0}'.format(VERSION), 'impl']
) as nsp:
generate_take(out_f, steps, nsp.prefix())
out_f.write(
'{0}template <int LenNow, int LenRemaining, char... Cs>\n'
'{0}struct make_string;\n'
'\n'
'{0}template <char... Cs>'
' struct make_string<0, 0, Cs...> : string<> {{}};\n'
.format(nsp.prefix())
)
disable_sun = False
for i in reversed(steps):
if i > 64 and not disable_sun:
out_f.write('#ifndef __SUNPRO_CC\n')
disable_sun = True
out_f.write(
'{0}template <int LenRemaining,{1}char... Cs>'
' struct make_string<{2},LenRemaining,{3}Cs...> :'
' concat<string<{4}>,'
' typename make_string<take(LenRemaining),'
'LenRemaining-take(LenRemaining),Cs...>::type> {{}};\n'
.format(
nsp.prefix(),
''.join('char {0},'.format(n) for n in unique_names(i)),
i,
''.join('{0},'.format(n) for n in unique_names(i)),
','.join(unique_names(i))
)
)
if disable_sun:
out_f.write('#endif\n')
def generate_string(out_dir, limits):
"""Generate string.hpp"""
max_limit = max((int(v) for v in limits))
with open(filename(out_dir, 'string'), 'wb') as out_f:
with IncludeGuard(out_f):
out_f.write(
'\n'
'#include <boost/metaparse/v{0}/cpp11/impl/concat.hpp>\n'
'#include <boost/preprocessor/cat.hpp>\n'
.format(VERSION)
)
generate_make_string(out_f, 512)
out_f.write(
'\n'
'#ifndef BOOST_METAPARSE_LIMIT_STRING_SIZE\n'
'# error BOOST_METAPARSE_LIMIT_STRING_SIZE not defined\n'
'#endif\n'
'\n'
'#if BOOST_METAPARSE_LIMIT_STRING_SIZE > {0}\n'
'# error BOOST_METAPARSE_LIMIT_STRING_SIZE is greater than'
' {0}. To increase the limit run tools/string_headers.py of'
' Boost.Metaparse against your Boost headers.\n'
'#endif\n'
'\n'
.format(max_limit)
)
define_macro(out_f, (
'STRING',
['s'],
'{0}::make_string< '
'{0}::take(sizeof(s)-1), sizeof(s)-1-{0}::take(sizeof(s)-1),'
'BOOST_PP_CAT({1}, BOOST_METAPARSE_LIMIT_STRING_SIZE)(s)'
'>::type'
.format(
'::boost::metaparse::v{0}::impl'.format(VERSION),
macro_name('I')
)
))
out_f.write('\n')
for limit in xrange(0, max_limit + 1):
out_f.write(
'#define {0} {1}\n'
.format(
macro_name('I{0}'.format(limit)),
macro_name('INDEX_STR{0}'.format(
min(int(l) for l in limits if int(l) >= limit)
))
)
)
out_f.write('\n')
prev_macro = None
prev_limit = 0
for length_limit in (int(l) for l in limits):
this_macro = macro_name('INDEX_STR{0}'.format(length_limit))
out_f.write(
'#define {0}(s) {1}{2}\n'
.format(
this_macro,
'{0}(s),'.format(prev_macro) if prev_macro else '',
','.join(
'{0}((s), {1})'
.format(macro_name('STRING_AT'), i)
for i in xrange(prev_limit, length_limit)
)
)
)
prev_macro = this_macro
prev_limit = length_limit
def positive_integer(value):
"""Throws when the argument is not a positive integer"""
val = int(value)
if val > 0:
return val
else:
raise argparse.ArgumentTypeError("A positive number is expected")
def existing_path(value):
"""Throws when the path does not exist"""
if os.path.exists(value):
return value
else:
raise argparse.ArgumentTypeError("Path {0} not found".format(value))
def main():
"""The main function of the script"""
parser = argparse.ArgumentParser(description=__doc__)
parser.add_argument(
'--boost_dir',
required=False,
type=existing_path,
help='The path to the include/boost directory of Metaparse'
)
parser.add_argument(
'--max_length_limit',
required=False,
default=2048,
type=positive_integer,
help='The maximum supported length limit'
)
parser.add_argument(
'--length_limit_step',
required=False,
default=128,
type=positive_integer,
help='The longest step at which headers are generated'
)
args = parser.parse_args()
if args.boost_dir is None:
tools_path = os.path.dirname(os.path.abspath(__file__))
boost_dir = os.path.join(
os.path.dirname(tools_path),
'include',
'boost'
)
else:
boost_dir = args.boost_dir
if args.max_length_limit < 1:
sys.stderr.write('Invalid maximum length limit')
sys.exit(-1)
generate_string(
os.path.join(
boost_dir,
'metaparse',
'v{0}'.format(VERSION),
'cpp11',
'impl'
),
length_limits(args.max_length_limit, args.length_limit_step)
)
if __name__ == '__main__':
main()