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## Copyright (C) 2004, 2005 Red Hat, Inc.
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## Written by Gary Benson <gbenson@redhat.com>
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## This program is free software; you can redistribute it and/or modify
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## it under the terms of the GNU General Public License as published by
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## the Free Software Foundation; either version 2 of the License, or
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## (at your option) any later version.
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## This program is distributed in the hope that it will be useful,
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## but WITHOUT ANY WARRANTY; without even the implied warranty of
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## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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## GNU General Public License for more details.
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"""Read Java(TM) class files."""
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import cStringIO as StringIO
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def __init__(self, arg):
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if hasattr(arg, "read"):
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elif type(arg) == type(""):
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if arg.startswith("\xca\xfe\xba\xbe"):
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self.fp = StringIO.StringIO(arg)
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self.fp = open(arg, "r")
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raise TypeError, type(arg)
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magic = self._read_int()
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assert magic == 0xcafebabeL
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minor, major = self._read(">HH")
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self.version = (major, minor)
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self.pool_integrity_checks = None
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except AssertionError:
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self.pool_integrity_checks = []
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self._read_constants_pool()
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self.access_flags = self._read_short()
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self.name = self._read_reference_Class()
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self.super = self._read_reference_Class()
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self.interfaces = self._read_interfaces()
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self.fields = self._read_fieldsormethods()
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self.methods = self._read_fieldsormethods()
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self.attributes = self._read_attributes()
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if self.pool_integrity_checks is not None:
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for index, tag in self.pool_integrity_checks:
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assert self.constants[index][0] == tag
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del self.fp, self.pool_integrity_checks
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attrs = [attr for attr in dir(self)
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if not attr.startswith("_") and attr != "Member"]
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result.append("%-13s %s" % (
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attr + ":", attr == "constants" and
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"<ELIDED>" or repr(getattr(self, attr))))
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return "\n".join(result)
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def _read_constants_pool(self):
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for i in xrange(1, self._read_short()):
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1: "Utf8", 3: "Integer", 4: "Float", 5: "Long",
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6: "Double", 7: "Class", 8: "String", 9: "Fieldref",
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10: "Methodref", 11: "InterfaceMethodref",
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12: "NameAndType"}[self._read_byte()]
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skip = tag in ("Long", "Double") # crack crack crack!
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self.constants[i] = (tag, getattr(self, "_read_constant_" + tag)())
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def _read_interfaces(self):
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for i in xrange(self._read_short()):
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result.append(self._read_reference_Class())
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def _read_fieldsormethods(self):
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for i in xrange(self._read_short()):
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result.append(self.Member(self))
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def __init__(self, source):
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self.access_flags = source._read_short()
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self.name = source._read_reference_Utf8()
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self.descriptor = source._read_reference_Utf8()
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self.attributes = source._read_attributes()
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attrs = [attr for attr in dir(self) if not attr.startswith("_")]
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value = getattr(self, attr)
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if attr == "attributes" and value.has_key("Code"):
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value.update({"Code": "<ELIDED>"})
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result.append("%-13s %s" % (
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attr + ":", repr(value).replace(
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"'Code': '<ELIDED>'", "'Code': <ELIDED>")))
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return ("\n%s" % (15 * " ")).join(result)
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def _read_attributes(self):
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for i in xrange(self._read_short()):
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name = self._read_reference_Utf8()
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data = self.fp.read(self._read_int())
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assert not result.has_key(name)
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# Constants pool reference reader convenience functions
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def _read_reference_Utf8(self):
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return self._read_references("Utf8")[0]
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def _read_reference_Class(self):
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return self._read_references("Class")[0]
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def _read_reference_Class_NameAndType(self):
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return self._read_references("Class", "NameAndType")
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def _read_references(self, *args):
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index = self._read_short()
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if self.pool_integrity_checks is not None:
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self.pool_integrity_checks.append((index, arg))
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# Constants pool constant reader functions
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def _read_constant_Utf8(self):
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constant = self.fp.read(self._read_short())
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constant = constant.decode("utf-8")
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constant = _bork_utf8_decode(constant)
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constant = constant.encode("us-ascii")
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def _read_constant_Integer(self):
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return self._read_int()
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def _read_constant_Float(self):
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return self._read(">f")[0]
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def _read_constant_Long(self):
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return self._read(">q")[0]
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def _read_constant_Double(self):
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return self._read(">d")[0]
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_read_constant_Class = _read_reference_Utf8
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_read_constant_String = _read_reference_Utf8
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_read_constant_Fieldref = _read_reference_Class_NameAndType
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_read_constant_Methodref = _read_reference_Class_NameAndType
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_read_constant_InterfaceMethodref = _read_reference_Class_NameAndType
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def _read_constant_NameAndType(self):
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return self._read_reference_Utf8(), self._read_reference_Utf8()
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# Generic reader functions
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# XXX how else to read 32 bits on a 64-bit box?
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h, l = map(long, self._read(">HH"))
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def _read_short(self):
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return self._read(">H")[0]
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def _read_byte(self):
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return self._read("B")[0]
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def _read(self, fmt):
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return struct.unpack(fmt, self.fp.read(struct.calcsize(fmt)))
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def _bork_utf8_decode(data):
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bytes, unicode = map(ord, data), ""
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assert b2 & 0xC0 == 0x80
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assert b3 & 0xC0 == 0x80
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((b1 & 0x0f) << 12) + ((b2 & 0x3f) << 6) + (b3 & 0x3f))
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unicode += unichr(((b1 & 0x1f) << 6) + (b2 & 0x3f))
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unicode += unichr(b1)
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if __name__ == "__main__":
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print Class("/usr/share/katana/build/ListDependentClasses.class")
added
removed
.svn/text-base/classfile.py.svn-base
