gecko-dev/config/make-windows-h-wrapper.py
Nika Layzell 568787b95f Bug 1448426 - Wrap windows.h to avoid problematic define statements, r=froydnj,glandium
By default, windows.h exposes a large number of problematic define statements
which are UpperCamelCase, such as a define from `CreateWindow` to
`CreateWindow{A,W}`.

As many of these names are generic (e.g. CreateFile, CreateWindow), they can
mess up Gecko code that may legitimately have its own methods with the same
names.

The header also defines some traditional SCREAMING_SNAKE_CASE defines which
can mess up our code by conflicting with local values.

This patch adds a simple code generator which generates wrappers for these
defines, and uses them to wrap the windows.h wrapper using the `stl_wrappers`
mechanism, allowing us to use windows.h in more places.

Differential Revision: https://phabricator.services.mozilla.com/D10932
2018-11-28 12:56:20 -05:00

87 lines
3.0 KiB
Python

# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.
import re
import textwrap
import string
from system_header_util import header_path
comment_re = re.compile(r'//[^\n]*\n|/\*.*\*/', re.S)
decl_re = re.compile(r'''^(.+)\s+ # type
(\w+)\s* # name
(?:\((.*)\))?$ # optional param tys
''', re.X | re.S)
def read_decls(filename):
"""Parse & yield C-style decls from an input file"""
with open(filename, 'r') as fd:
# Strip comments from the source text.
text = comment_re.sub('', fd.read())
# Parse individual declarations.
raw_decls = [d.strip() for d in text.split(';') if d.strip()]
for raw in raw_decls:
match = decl_re.match(raw)
if match is None:
raise "Invalid decl: %s" % raw
ty, name, params = match.groups()
if params is not None:
params = [a.strip() for a in params.split(',') if a.strip()]
yield ty, name, params
def generate(fd, consts_path, unicodes_path, template_path, compiler):
# Parse the template
with open(template_path, 'r') as template_fd:
template = string.Template(template_fd.read())
decls = ''
# Each constant should be saved to a temporary, and then re-assigned to a
# constant with the correct name, allowing the value to be determined by
# the actual definition.
for ty, name, args in read_decls(consts_path):
assert args is None, "parameters in const decl!"
decls += textwrap.dedent("""
#ifdef {name}
constexpr {ty} _tmp_{name} = {name};
#undef {name}
constexpr {ty} {name} = _tmp_{name};
#endif
""".format(ty=ty, name=name))
# Each unicode declaration defines a static inline function with the
# correct types which calls the 'A' or 'W'-suffixed versions of the
# function. Full types are required here to ensure that '0' to 'nullptr'
# coersions are preserved.
for ty, name, args in read_decls(unicodes_path):
assert args is not None, "argument list required for unicode decl"
# Parameter & argument string list
params = ', '.join('%s a%d' % (ty, i) for i, ty in enumerate(args))
args = ', '.join('a%d' % i for i in range(len(args)))
decls += textwrap.dedent("""
#ifdef {name}
#undef {name}
static inline {ty} WINAPI
{name}({params})
{{
#ifdef UNICODE
return {name}W({args});
#else
return {name}A({args});
#endif
}}
#endif
""".format(ty=ty, name=name, params=params, args=args))
path = header_path('windows.h', compiler)
# Write out the resulting file
fd.write(template.substitute(header_path=path, decls=decls))