Application: gvSIG desktop » gvSIG scripting

"""Disassembler of Python byte code into mnemonics."""

import sys

import types

__all__ = ["dis","disassemble","distb","disco","opname","cmp_op",

           "hasconst","hasname","hasjrel","hasjabs","haslocal",

           "hascompare", "hasfree"]

def dis(x=None):

    """Disassemble classes, methods, functions, or code.

    With no argument, disassemble the last traceback.

    """

    if not x:

        distb()

        return

    if type(x) is types.InstanceType:

        x = x.__class__

    if hasattr(x, 'im_func'):

        x = x.im_func

    if hasattr(x, 'func_code'):

        x = x.func_code

    if hasattr(x, '__dict__'):

        items = x.__dict__.items()

        items.sort()

        for name, x1 in items:

            if type(x1) in (types.MethodType,

                            types.FunctionType,

                            types.CodeType):

                print "Disassembly of %s:" % name

                try:

                    dis(x1)

                except TypeError, msg:

                    print "Sorry:", msg

                print

    elif hasattr(x, 'co_code'):

        disassemble(x)

    else:

        raise TypeError, \

              "don't know how to disassemble %s objects" % \

              type(x).__name__

def distb(tb=None):

    """Disassemble a traceback (default: last traceback)."""

    if not tb:

        try:

            tb = sys.last_traceback

        except AttributeError:

            raise RuntimeError, "no last traceback to disassemble"

        while tb.tb_next: tb = tb.tb_next

    disassemble(tb.tb_frame.f_code, tb.tb_lasti)

def disassemble(co, lasti=-1):

    """Disassemble a code object."""

    code = co.co_code

    labels = findlabels(code)

    n = len(code)

    i = 0

    extended_arg = 0

    free = None

    while i < n:

        c = code[i]

        op = ord(c)

        if op == SET_LINENO and i > 0: print # Extra blank line

        if i == lasti: print '-->',

        else: print '   ',

        if i in labels: print '>>',

        else: print '  ',

        print `i`.rjust(4),

        print opname[op].ljust(20),

        i = i+1

        if op >= HAVE_ARGUMENT:

            oparg = ord(code[i]) + ord(code[i+1])*256 + extended_arg

            extended_arg = 0

            i = i+2

            if op == EXTENDED_ARG:

                extended_arg = oparg*65536L

            print `oparg`.rjust(5),

            if op in hasconst:

                print '(' + `co.co_consts[oparg]` + ')',

            elif op in hasname:

                print '(' + co.co_names[oparg] + ')',

            elif op in hasjrel:

                print '(to ' + `i + oparg` + ')',

            elif op in haslocal:

                print '(' + co.co_varnames[oparg] + ')',

            elif op in hascompare:

                print '(' + cmp_op[oparg] + ')',

            elif op in hasfree:

                if free is None:

                    free = co.co_cellvars + co.co_freevars

                print '(' + free[oparg] + ')',

        print

disco = disassemble                     # XXX For backwards compatibility

def findlabels(code):

    """Detect all offsets in a byte code which are jump targets.

    Return the list of offsets.

    """

    labels = []

    n = len(code)

    i = 0

    while i < n:

        c = code[i]

        op = ord(c)

        i = i+1

        if op >= HAVE_ARGUMENT:

            oparg = ord(code[i]) + ord(code[i+1])*256

            i = i+2

            label = -1

            if op in hasjrel:

                label = i+oparg

            elif op in hasjabs:

                label = oparg

            if label >= 0:

                if label not in labels:

                    labels.append(label)

    return labels

cmp_op = ('<', '<=', '==', '!=', '>', '>=', 'in', 'not in', 'is',

        'is not', 'exception match', 'BAD')

hasconst = []

hasname = []

hasjrel = []

hasjabs = []

haslocal = []

hascompare = []

hasfree = []

opname = [''] * 256

for op in range(256): opname[op] = '<' + `op` + '>'

def def_op(name, op):

    opname[op] = name

def name_op(name, op):

    opname[op] = name

    hasname.append(op)

def jrel_op(name, op):

    opname[op] = name

    hasjrel.append(op)

def jabs_op(name, op):

    opname[op] = name

    hasjabs.append(op)

# Instruction opcodes for compiled code

def_op('STOP_CODE', 0)

def_op('POP_TOP', 1)

def_op('ROT_TWO', 2)

def_op('ROT_THREE', 3)

def_op('DUP_TOP', 4)

def_op('ROT_FOUR', 5)

def_op('UNARY_POSITIVE', 10)

def_op('UNARY_NEGATIVE', 11)

def_op('UNARY_NOT', 12)

def_op('UNARY_CONVERT', 13)

def_op('UNARY_INVERT', 15)

def_op('BINARY_POWER', 19)

def_op('BINARY_MULTIPLY', 20)

def_op('BINARY_DIVIDE', 21)

def_op('BINARY_MODULO', 22)

def_op('BINARY_ADD', 23)

def_op('BINARY_SUBTRACT', 24)

def_op('BINARY_SUBSCR', 25)

def_op('BINARY_FLOOR_DIVIDE', 26)

def_op('BINARY_TRUE_DIVIDE', 27)

def_op('INPLACE_FLOOR_DIVIDE', 28)

def_op('INPLACE_TRUE_DIVIDE', 29)

def_op('SLICE+0', 30)

def_op('SLICE+1', 31)

def_op('SLICE+2', 32)

def_op('SLICE+3', 33)

def_op('STORE_SLICE+0', 40)

def_op('STORE_SLICE+1', 41)

def_op('STORE_SLICE+2', 42)

def_op('STORE_SLICE+3', 43)

def_op('DELETE_SLICE+0', 50)

def_op('DELETE_SLICE+1', 51)

def_op('DELETE_SLICE+2', 52)

def_op('DELETE_SLICE+3', 53)

def_op('INPLACE_ADD', 55)

def_op('INPLACE_SUBTRACT', 56)

def_op('INPLACE_MULTIPLY', 57)

def_op('INPLACE_DIVIDE', 58)

def_op('INPLACE_MODULO', 59)

def_op('STORE_SUBSCR', 60)

def_op('DELETE_SUBSCR', 61)

def_op('BINARY_LSHIFT', 62)

def_op('BINARY_RSHIFT', 63)

def_op('BINARY_AND', 64)

def_op('BINARY_XOR', 65)

def_op('BINARY_OR', 66)

def_op('INPLACE_POWER', 67)

def_op('GET_ITER', 68)

def_op('PRINT_EXPR', 70)

def_op('PRINT_ITEM', 71)

def_op('PRINT_NEWLINE', 72)

def_op('PRINT_ITEM_TO', 73)

def_op('PRINT_NEWLINE_TO', 74)

def_op('INPLACE_LSHIFT', 75)

def_op('INPLACE_RSHIFT', 76)

def_op('INPLACE_AND', 77)

def_op('INPLACE_XOR', 78)

def_op('INPLACE_OR', 79)

def_op('BREAK_LOOP', 80)

def_op('LOAD_LOCALS', 82)

def_op('RETURN_VALUE', 83)

def_op('IMPORT_STAR', 84)

def_op('EXEC_STMT', 85)

def_op('YIELD_STMT', 86)

def_op('POP_BLOCK', 87)

def_op('END_FINALLY', 88)

def_op('BUILD_CLASS', 89)

HAVE_ARGUMENT = 90              # Opcodes from here have an argument:

name_op('STORE_NAME', 90)       # Index in name list

name_op('DELETE_NAME', 91)      # ""

def_op('UNPACK_SEQUENCE', 92)   # Number of tuple items

jrel_op('FOR_ITER', 93)

name_op('STORE_ATTR', 95)       # Index in name list

name_op('DELETE_ATTR', 96)      # ""

name_op('STORE_GLOBAL', 97)     # ""

name_op('DELETE_GLOBAL', 98)    # ""

def_op('DUP_TOPX', 99)          # number of items to duplicate

def_op('LOAD_CONST', 100)       # Index in const list

hasconst.append(100)

name_op('LOAD_NAME', 101)       # Index in name list

def_op('BUILD_TUPLE', 102)      # Number of tuple items

def_op('BUILD_LIST', 103)       # Number of list items

def_op('BUILD_MAP', 104)        # Always zero for now

name_op('LOAD_ATTR', 105)       # Index in name list

def_op('COMPARE_OP', 106)       # Comparison operator

hascompare.append(106)

name_op('IMPORT_NAME', 107)     # Index in name list

name_op('IMPORT_FROM', 108)     # Index in name list

jrel_op('JUMP_FORWARD', 110)    # Number of bytes to skip

jrel_op('JUMP_IF_FALSE', 111)   # ""

jrel_op('JUMP_IF_TRUE', 112)    # ""

jabs_op('JUMP_ABSOLUTE', 113)   # Target byte offset from beginning of code

jrel_op('FOR_LOOP', 114)        # Number of bytes to skip

name_op('LOAD_GLOBAL', 116)     # Index in name list

jabs_op('CONTINUE_LOOP', 119)   # Target address

jrel_op('SETUP_LOOP', 120)      # Distance to target address

jrel_op('SETUP_EXCEPT', 121)    # ""

jrel_op('SETUP_FINALLY', 122)   # ""

def_op('LOAD_FAST', 124)        # Local variable number

haslocal.append(124)

def_op('STORE_FAST', 125)       # Local variable number

haslocal.append(125)

def_op('DELETE_FAST', 126)      # Local variable number

haslocal.append(126)

def_op('SET_LINENO', 127)       # Current line number

SET_LINENO = 127

def_op('RAISE_VARARGS', 130)    # Number of raise arguments (1, 2, or 3)

def_op('CALL_FUNCTION', 131)    # #args + (#kwargs << 8)

def_op('MAKE_FUNCTION', 132)    # Number of args with default values

def_op('BUILD_SLICE', 133)      # Number of items

def_op('MAKE_CLOSURE', 134)

def_op('LOAD_CLOSURE', 135)

hasfree.append(135)

def_op('LOAD_DEREF', 136)

hasfree.append(136)

def_op('STORE_DEREF', 137)

hasfree.append(137)

def_op('CALL_FUNCTION_VAR', 140)     # #args + (#kwargs << 8)

def_op('CALL_FUNCTION_KW', 141)      # #args + (#kwargs << 8)

def_op('CALL_FUNCTION_VAR_KW', 142)  # #args + (#kwargs << 8)

def_op('EXTENDED_ARG', 143)

EXTENDED_ARG = 143

def _test():

    """Simple test program to disassemble a file."""

    if sys.argv[1:]:

        if sys.argv[2:]:

            sys.stderr.write("usage: python dis.py [-|file]\n")

            sys.exit(2)

        fn = sys.argv[1]

        if not fn or fn == "-":

            fn = None

    else:

        fn = None

    if not fn:

        f = sys.stdin

    else:

        f = open(fn)

    source = f.read()

    if fn:

        f.close()

    else:

        fn = "<stdin>"

    code = compile(source, fn, "exec")

    dis(code)

if __name__ == "__main__":

    _test()