| #!/usr/bin/env python3 |
| # Copyright 2015 The Chromium Authors |
| # Use of this source code is governed by a BSD-style license that can be |
| # found in the LICENSE file. |
| |
| # This writes headers for build flags. See buildflag_header.gni for usage of |
| # this system as a whole. |
| # |
| # The parameters are passed in a response file so we don't have to worry |
| # about command line lengths. The name of the response file is passed on the |
| # command line. |
| # |
| # The format of the response file is: |
| # [--flags <list of one or more flag values>] |
| |
| import optparse |
| import os |
| import re |
| import shlex |
| |
| |
| class Options: |
| def __init__(self, output, rulename, header_guard, flags): |
| self.output = output |
| self.rulename = rulename |
| self.header_guard = header_guard |
| self.flags = flags |
| |
| |
| def GetOptions(): |
| parser = optparse.OptionParser() |
| parser.add_option('--output', help="Output header name inside --gen-dir.") |
| parser.add_option('--rulename', |
| help="Helpful name of build rule for including in the " + |
| "comment at the top of the file.") |
| parser.add_option('--gen-dir', |
| help="Path to root of generated file directory tree.") |
| parser.add_option('--definitions', |
| help="Name of the response file containing the flags.") |
| cmdline_options, cmdline_flags = parser.parse_args() |
| |
| # Compute a valid C++ header guard by replacing non valid chars with '_', |
| # upper-casing everything and prepending '_' if first symbol is digit. |
| header_guard = cmdline_options.output.upper() |
| if header_guard[0].isdigit(): |
| header_guard = '_' + header_guard |
| header_guard = re.sub(r'[^\w]', '_', header_guard) |
| header_guard += '_' |
| |
| # The actual output file is inside the gen dir. |
| output = os.path.join(cmdline_options.gen_dir, cmdline_options.output) |
| |
| # Definition file in GYP is newline separated, in GN they are shell formatted. |
| # shlex can parse both of these. |
| with open(cmdline_options.definitions, 'r') as def_file: |
| defs = shlex.split(def_file.read()) |
| flags_index = defs.index('--flags') |
| |
| # Everything after --flags are flags. true/false are remapped to 1/0, |
| # everything else is passed through. |
| flags = [] |
| for flag in defs[flags_index + 1 :]: |
| equals_index = flag.index('=') |
| key = flag[:equals_index] |
| value = flag[equals_index + 1:] |
| |
| # Canonicalize and validate the value. |
| if value == 'true': |
| value = '1' |
| elif value == 'false': |
| value = '0' |
| flags.append((key, str(value))) |
| |
| return Options(output=output, |
| rulename=cmdline_options.rulename, |
| header_guard=header_guard, |
| flags=flags) |
| |
| |
| def WriteHeader(options): |
| with open(options.output, 'w') as output_file: |
| output_file.write("// Generated by build/write_buildflag_header.py\n") |
| if options.rulename: |
| output_file.write('// From "' + options.rulename + '"\n') |
| |
| output_file.write('\n#ifndef %s\n' % options.header_guard) |
| output_file.write('#define %s\n\n' % options.header_guard) |
| output_file.write('#include "build/buildflag.h" // IWYU pragma: export\n\n') |
| # Clangd does not detect BUILDFLAG_INTERNAL_* indirect usage, so mark the |
| # header as "always_keep" to avoid "unused include" warning. |
| output_file.write('// IWYU pragma: always_keep\n\n') |
| |
| for pair in options.flags: |
| output_file.write('#define BUILDFLAG_INTERNAL_%s() (%s)\n' % pair) |
| |
| output_file.write('\n#endif // %s\n' % options.header_guard) |
| |
| |
| options = GetOptions() |
| WriteHeader(options) |