icuSources/test/depstest/depstest.py

   1 #! /usr/bin/python
   2 # -*- coding: utf-8 -*-
   3 #
   4 # Copyright (C) 2011, International Business Machines
   5 # Corporation and others. All Rights Reserved.
   6 #
   7 # file name: depstest.py
   8 #
   9 # created on: 2011may24
  10
  11 """ICU dependency tester.
  12
  13 This probably works only on Linux.
  14
  15 The exit code is 0 if everything is fine, 1 for errors, 2 for only warnings.
  16
  17 Sample invocation:
  18   ~/svn.icu/trunk/src/source/test/depstest$ ./depstest.py ~/svn.icu/trunk/dbg
  19 """
  20
  21 __author__ = "Markus W. Scherer"
  22
  23 import glob
  24 import os.path
  25 import subprocess
  26 import sys
  27
  28 import dependencies
  29
  30 _ignored_symbols = set()
  31 _obj_files = {}
  32 _symbols_to_files = {}
  33 _return_value = 0
  34
  35 # Classes with vtables (and thus virtual methods).
  36 _virtual_classes = set()
  37 # Classes with weakly defined destructors.
  38 # nm shows a symbol class of "W" rather than "T".
  39 _weak_destructors = set()
  40
  41 def _ReadObjFile(root_path, library_name, obj_name):
  42   global _ignored_symbols, _obj_files, _symbols_to_files
  43   global _virtual_classes, _weak_destructors
  44   lib_obj_name = library_name + "/" + obj_name
  45   if lib_obj_name in _obj_files:
  46     print "Warning: duplicate .o file " + lib_obj_name
  47     _return_value = 2
  48     return
  49
  50   path = os.path.join(root_path, library_name, obj_name)
  51   nm_result = subprocess.Popen(["nm", "--demangle", "--format=sysv",
  52                                 "--extern-only", "--no-sort", path],
  53                                stdout=subprocess.PIPE).communicate()[0]
  54   obj_imports = set()
  55   obj_exports = set()
  56   for line in nm_result.splitlines():
  57     fields = line.split("|")
  58     if len(fields) == 1: continue
  59     name = fields[0].strip()
  60     # Ignore symbols like '__cxa_pure_virtual',
  61     # 'vtable for __cxxabiv1::__si_class_type_info' or
  62     # 'DW.ref.__gxx_personality_v0'.
  63     if name.startswith("__cxa") or "__cxxabi" in name or "__gxx" in name:
  64       _ignored_symbols.add(name)
  65       continue
  66     type = fields[2].strip()
  67     if type == "U":
  68       obj_imports.add(name)
  69     else:
  70       obj_exports.add(name)
  71       _symbols_to_files[name] = lib_obj_name
  72       # Is this a vtable? E.g., "vtable for icu_49::ByteSink".
  73       if name.startswith("vtable for icu"):
  74         _virtual_classes.add(name[name.index("::") + 2:])
  75       # Is this a destructor? E.g., "icu_49::ByteSink::~ByteSink()".
  76       index = name.find("::~")
  77       if index >= 0 and type == "W":
  78         _weak_destructors.add(name[index + 3:name.index("(", index)])
  79   _obj_files[lib_obj_name] = {"imports": obj_imports, "exports": obj_exports}
  80
  81 def _ReadLibrary(root_path, library_name):
  82   obj_paths = glob.glob(os.path.join(root_path, library_name, "*.o"))
  83   for path in obj_paths:
  84     _ReadObjFile(root_path, library_name, os.path.basename(path))
  85
  86 def _Resolve(name, parents):
  87   global _ignored_symbols, _obj_files, _symbols_to_files, _return_value
  88   item = dependencies.items[name]
  89   item_type = item["type"]
  90   if name in parents:
  91     sys.exit("Error: %s %s has a circular dependency on itself: %s" %
  92              (item_type, name, parents))
  93   # Check if already cached.
  94   exports = item.get("exports")
  95   if exports != None: return item
  96   # Calculcate recursively.
  97   parents.append(name)
  98   imports = set()
  99   exports = set()
 100   system_symbols = item.get("system_symbols")
 101   if system_symbols == None: system_symbols = item["system_symbols"] = set()
 102   files = item.get("files")
 103   if files:
 104     for file_name in files:
 105       obj_file = _obj_files[file_name]
 106       imports |= obj_file["imports"]
 107       exports |= obj_file["exports"]
 108   imports -= exports | _ignored_symbols
 109   deps = item.get("deps")
 110   if deps:
 111     for dep in deps:
 112       dep_item = _Resolve(dep, parents)
 113       # Detect whether this item needs to depend on dep,
 114       # except when this item has no files, that is, when it is just
 115       # a deliberate umbrella group or library.
 116       dep_exports = dep_item["exports"]
 117       dep_system_symbols = dep_item["system_symbols"]
 118       if files and imports.isdisjoint(dep_exports) and imports.isdisjoint(dep_system_symbols):
 119         print "Info:  %s %s  does not need to depend on  %s\n" % (item_type, name, dep)
 120       # We always include the dependency's exports, even if we do not need them
 121       # to satisfy local imports.
 122       exports |= dep_exports
 123       system_symbols |= dep_system_symbols
 124   item["exports"] = exports
 125   item["system_symbols"] = system_symbols
 126   imports -= exports | system_symbols
 127   for symbol in imports:
 128     for file_name in files:
 129       if symbol in _obj_files[file_name]["imports"]:
 130         sys.stderr.write("Error:  %s %s  file  %s  imports  %s  but  %s  does not depend on  %s\n" %
 131                          (item_type, name, file_name, symbol, name, _symbols_to_files.get(symbol)))
 132     _return_value = 1
 133   del parents[-1]
 134   return item
 135
 136 def Process(root_path):
 137   """Loads dependencies.txt, reads the libraries' .o files, and processes them.
 138
 139   Modifies dependencies.items: Recursively builds each item's system_symbols and exports.
 140   """
 141   global _ignored_symbols, _obj_files, _return_value
 142   global _virtual_classes, _weak_destructors
 143   dependencies.Load()
 144   for name_and_item in dependencies.items.iteritems():
 145     name = name_and_item[0]
 146     item = name_and_item[1]
 147     system_symbols = item.get("system_symbols")
 148     if system_symbols:
 149       for symbol in system_symbols:
 150         _symbols_to_files[symbol] = name
 151   for library_name in dependencies.libraries:
 152     _ReadLibrary(root_path, library_name)
 153   o_files_set = set(_obj_files.keys())
 154   files_missing_from_deps = o_files_set - dependencies.files
 155   files_missing_from_build = dependencies.files - o_files_set
 156   if files_missing_from_deps:
 157     sys.stderr.write("Error: files missing from dependencies.txt:\n%s\n" %
 158                      sorted(files_missing_from_deps))
 159     _return_value = 1
 160   if files_missing_from_build:
 161     sys.stderr.write("Error: files in dependencies.txt but not built:\n%s\n" %
 162                      sorted(files_missing_from_build))
 163     _return_value = 1
 164   if not _return_value:
 165     for library_name in dependencies.libraries:
 166       _Resolve(library_name, [])
 167   if not _return_value:
 168     virtual_classes_with_weak_destructors = _virtual_classes & _weak_destructors
 169     if virtual_classes_with_weak_destructors:
 170       sys.stderr.write("Error: Some classes have virtual methods, and "
 171                        "an implicit or inline destructor "
 172                        "(see ICU ticket #8454 for details):\n%s\n" %
 173                        sorted(virtual_classes_with_weak_destructors))
 174       _return_value = 1
 175
 176 def main():
 177   global _return_value
 178   if len(sys.argv) <= 1:
 179     sys.exit(("Command line error: " +
 180              "need one argument with the root path to the built ICU libraries/*.o files."))
 181   Process(sys.argv[1])
 182   if _ignored_symbols:
 183     print "Info: ignored symbols:\n%s" % sorted(_ignored_symbols)
 184   if not _return_value:
 185     print "OK: Specified and actual dependencies match."
 186   return _return_value
 187
 188 if __name__ == "__main__":
 189   sys.exit(main())