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-rw-r--r--engine/SCons/dblite.py248
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diff --git a/engine/SCons/dblite.py b/engine/SCons/dblite.py
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+# dblite.py module contributed by Ralf W. Grosse-Kunstleve.
+# Extended for Unicode by Steven Knight.
+
+import cPickle
+import time
+import shutil
+import os
+import types
+import __builtin__
+
+keep_all_files = 00000
+ignore_corrupt_dbfiles = 0
+
+def corruption_warning(filename):
+ print "Warning: Discarding corrupt database:", filename
+
+if hasattr(types, 'UnicodeType'):
+ def is_string(s):
+ t = type(s)
+ return t is types.StringType or t is types.UnicodeType
+else:
+ def is_string(s):
+ return type(s) is types.StringType
+
+try:
+ unicode('a')
+except NameError:
+ def unicode(s): return s
+
+dblite_suffix = '.dblite'
+tmp_suffix = '.tmp'
+
+class dblite:
+
+ # Squirrel away references to the functions in various modules
+ # that we'll use when our __del__() method calls our sync() method
+ # during shutdown. We might get destroyed when Python is in the midst
+ # of tearing down the different modules we import in an essentially
+ # arbitrary order, and some of the various modules's global attributes
+ # may already be wiped out from under us.
+ #
+ # See the discussion at:
+ # http://mail.python.org/pipermail/python-bugs-list/2003-March/016877.html
+
+ _open = __builtin__.open
+ _cPickle_dump = cPickle.dump
+ _os_chmod = os.chmod
+ try:
+ _os_chown = os.chown
+ except AttributeError:
+ _os_chown = None
+ _os_rename = os.rename
+ _os_unlink = os.unlink
+ _shutil_copyfile = shutil.copyfile
+ _time_time = time.time
+
+ def __init__(self, file_base_name, flag, mode):
+ assert flag in (None, "r", "w", "c", "n")
+ if (flag is None): flag = "r"
+ base, ext = os.path.splitext(file_base_name)
+ if ext == dblite_suffix:
+ # There's already a suffix on the file name, don't add one.
+ self._file_name = file_base_name
+ self._tmp_name = base + tmp_suffix
+ else:
+ self._file_name = file_base_name + dblite_suffix
+ self._tmp_name = file_base_name + tmp_suffix
+ self._flag = flag
+ self._mode = mode
+ self._dict = {}
+ self._needs_sync = 00000
+ if self._os_chown is not None and (os.geteuid()==0 or os.getuid()==0):
+ # running as root; chown back to current owner/group when done
+ try:
+ statinfo = os.stat(self._file_name)
+ self._chown_to = statinfo.st_uid
+ self._chgrp_to = statinfo.st_gid
+ except OSError, e:
+ # db file doesn't exist yet.
+ # Check os.environ for SUDO_UID, use if set
+ self._chown_to = int(os.environ.get('SUDO_UID', -1))
+ self._chgrp_to = int(os.environ.get('SUDO_GID', -1))
+ else:
+ self._chown_to = -1 # don't chown
+ self._chgrp_to = -1 # don't chgrp
+ if (self._flag == "n"):
+ self._open(self._file_name, "wb", self._mode)
+ else:
+ try:
+ f = self._open(self._file_name, "rb")
+ except IOError, e:
+ if (self._flag != "c"):
+ raise e
+ self._open(self._file_name, "wb", self._mode)
+ else:
+ p = f.read()
+ if (len(p) > 0):
+ try:
+ self._dict = cPickle.loads(p)
+ except (cPickle.UnpicklingError, EOFError):
+ if (ignore_corrupt_dbfiles == 0): raise
+ if (ignore_corrupt_dbfiles == 1):
+ corruption_warning(self._file_name)
+
+ def __del__(self):
+ if (self._needs_sync):
+ self.sync()
+
+ def sync(self):
+ self._check_writable()
+ f = self._open(self._tmp_name, "wb", self._mode)
+ self._cPickle_dump(self._dict, f, 1)
+ f.close()
+ # Windows doesn't allow renaming if the file exists, so unlink
+ # it first, chmod'ing it to make sure we can do so. On UNIX, we
+ # may not be able to chmod the file if it's owned by someone else
+ # (e.g. from a previous run as root). We should still be able to
+ # unlink() the file if the directory's writable, though, so ignore
+ # any OSError exception thrown by the chmod() call.
+ try: self._os_chmod(self._file_name, 0777)
+ except OSError: pass
+ self._os_unlink(self._file_name)
+ self._os_rename(self._tmp_name, self._file_name)
+ if self._os_chown is not None and self._chown_to > 0: # don't chown to root or -1
+ try:
+ self._os_chown(self._file_name, self._chown_to, self._chgrp_to)
+ except OSError:
+ pass
+ self._needs_sync = 00000
+ if (keep_all_files):
+ self._shutil_copyfile(
+ self._file_name,
+ self._file_name + "_" + str(int(self._time_time())))
+
+ def _check_writable(self):
+ if (self._flag == "r"):
+ raise IOError("Read-only database: %s" % self._file_name)
+
+ def __getitem__(self, key):
+ return self._dict[key]
+
+ def __setitem__(self, key, value):
+ self._check_writable()
+ if (not is_string(key)):
+ raise TypeError, "key `%s' must be a string but is %s" % (key, type(key))
+ if (not is_string(value)):
+ raise TypeError, "value `%s' must be a string but is %s" % (value, type(value))
+ self._dict[key] = value
+ self._needs_sync = 0001
+
+ def keys(self):
+ return self._dict.keys()
+
+ def has_key(self, key):
+ return key in self._dict
+
+ def __contains__(self, key):
+ return key in self._dict
+
+ def iterkeys(self):
+ return self._dict.iterkeys()
+
+ __iter__ = iterkeys
+
+ def __len__(self):
+ return len(self._dict)
+
+def open(file, flag=None, mode=0666):
+ return dblite(file, flag, mode)
+
+def _exercise():
+ db = open("tmp", "n")
+ assert len(db) == 0
+ db["foo"] = "bar"
+ assert db["foo"] == "bar"
+ db[unicode("ufoo")] = unicode("ubar")
+ assert db[unicode("ufoo")] == unicode("ubar")
+ db.sync()
+ db = open("tmp", "c")
+ assert len(db) == 2, len(db)
+ assert db["foo"] == "bar"
+ db["bar"] = "foo"
+ assert db["bar"] == "foo"
+ db[unicode("ubar")] = unicode("ufoo")
+ assert db[unicode("ubar")] == unicode("ufoo")
+ db.sync()
+ db = open("tmp", "r")
+ assert len(db) == 4, len(db)
+ assert db["foo"] == "bar"
+ assert db["bar"] == "foo"
+ assert db[unicode("ufoo")] == unicode("ubar")
+ assert db[unicode("ubar")] == unicode("ufoo")
+ try:
+ db.sync()
+ except IOError, e:
+ assert str(e) == "Read-only database: tmp.dblite"
+ else:
+ raise RuntimeError, "IOError expected."
+ db = open("tmp", "w")
+ assert len(db) == 4
+ db["ping"] = "pong"
+ db.sync()
+ try:
+ db[(1,2)] = "tuple"
+ except TypeError, e:
+ assert str(e) == "key `(1, 2)' must be a string but is <type 'tuple'>", str(e)
+ else:
+ raise RuntimeError, "TypeError exception expected"
+ try:
+ db["list"] = [1,2]
+ except TypeError, e:
+ assert str(e) == "value `[1, 2]' must be a string but is <type 'list'>", str(e)
+ else:
+ raise RuntimeError, "TypeError exception expected"
+ db = open("tmp", "r")
+ assert len(db) == 5
+ db = open("tmp", "n")
+ assert len(db) == 0
+ _open("tmp.dblite", "w")
+ db = open("tmp", "r")
+ _open("tmp.dblite", "w").write("x")
+ try:
+ db = open("tmp", "r")
+ except cPickle.UnpicklingError:
+ pass
+ else:
+ raise RuntimeError, "cPickle exception expected."
+ global ignore_corrupt_dbfiles
+ ignore_corrupt_dbfiles = 2
+ db = open("tmp", "r")
+ assert len(db) == 0
+ os.unlink("tmp.dblite")
+ try:
+ db = open("tmp", "w")
+ except IOError, e:
+ assert str(e) == "[Errno 2] No such file or directory: 'tmp.dblite'", str(e)
+ else:
+ raise RuntimeError, "IOError expected."
+ print "OK"
+
+if (__name__ == "__main__"):
+ _exercise()
+
+# Local Variables:
+# tab-width:4
+# indent-tabs-mode:nil
+# End:
+# vim: set expandtab tabstop=4 shiftwidth=4: