1 #!/usr/bin/env python 2 # Copyright (c) 2012 The Chromium Authors. All rights reserved. 3 # Use of this source code is governed by a BSD-style license that can be 4 # found in the LICENSE file. 5 6 """ 7 Generates shim headers that mirror the directory structure of bundled headers, 8 but just forward to the system ones. 9 10 This allows seamless compilation against system headers with no changes 11 to our source code. 12 """ 13 14 15 import optparse 16 import os.path 17 import sys 18 19 20 SHIM_TEMPLATE = """ 21 #if defined(OFFICIAL_BUILD) 22 #error shim headers must not be used in official builds! 23 #endif 24 """ 25 26 27 def GeneratorMain(argv): 28 parser = optparse.OptionParser() 29 parser.add_option('--headers-root', action='append') 30 parser.add_option('--define', action='append') 31 parser.add_option('--output-directory') 32 parser.add_option('--prefix', default='') 33 parser.add_option('--use-include-next', action='store_true') 34 parser.add_option('--outputs', action='store_true') 35 parser.add_option('--generate', action='store_true') 36 37 options, args = parser.parse_args(argv) 38 39 if not options.headers_root: 40 parser.error('Missing --headers-root parameter.') 41 if not options.output_directory: 42 parser.error('Missing --output-directory parameter.') 43 if not args: 44 parser.error('Missing arguments - header file names.') 45 46 source_tree_root = os.path.abspath( 47 os.path.join(os.path.dirname(__file__), '..', '..')) 48 49 for root in options.headers_root: 50 target_directory = os.path.join( 51 options.output_directory, 52 os.path.relpath(root, source_tree_root)) 53 if options.generate and not os.path.exists(target_directory): 54 os.makedirs(target_directory) 55 56 for header_spec in args: 57 if ';' in header_spec: 58 (header_filename, 59 include_before, 60 include_after) = header_spec.split(';', 2) 61 else: 62 header_filename = header_spec 63 include_before = '' 64 include_after = '' 65 if options.outputs: 66 yield os.path.join(target_directory, header_filename) 67 if options.generate: 68 with open(os.path.join(target_directory, header_filename), 'w') as f: 69 f.write(SHIM_TEMPLATE) 70 71 if options.define: 72 for define in options.define: 73 key, value = define.split('=', 1) 74 # This non-standard push_macro extension is supported 75 # by compilers we support (GCC, clang). 76 f.write('#pragma push_macro("%s")\n' % key) 77 f.write('#undef %s\n' % key) 78 f.write('#define %s %s\n' % (key, value)) 79 80 if include_before: 81 for header in include_before.split(':'): 82 f.write('#include %s\n' % header) 83 84 include_target = options.prefix + header_filename 85 if options.use_include_next: 86 f.write('#include_next <%s>\n' % include_target) 87 else: 88 f.write('#include <%s>\n' % include_target) 89 90 if include_after: 91 for header in include_after.split(':'): 92 f.write('#include %s\n' % header) 93 94 if options.define: 95 for define in options.define: 96 key, value = define.split('=', 1) 97 # This non-standard pop_macro extension is supported 98 # by compilers we support (GCC, clang). 99 f.write('#pragma pop_macro("%s")\n' % key) 100 101 102 def DoMain(argv): 103 return '\n'.join(GeneratorMain(argv)) 104 105 106 if __name__ == '__main__': 107 DoMain(sys.argv[1:]) 108
