AlkantarClanX12
Current Path : /proc/self/root/opt/alt/python33/lib64/python3.3/ |
Current File : //proc/self/root/opt/alt/python33/lib64/python3.3/dis.py |
"""Disassembler of Python byte code into mnemonics.""" import sys import types from opcode import * from opcode import __all__ as _opcodes_all __all__ = ["code_info", "dis", "disassemble", "distb", "disco", "findlinestarts", "findlabels", "show_code"] + _opcodes_all del _opcodes_all _have_code = (types.MethodType, types.FunctionType, types.CodeType, type) def _try_compile(source, name): """Attempts to compile the given source, first as an expression and then as a statement if the first approach fails. Utility function to accept strings in functions that otherwise expect code objects """ try: c = compile(source, name, 'eval') except SyntaxError: c = compile(source, name, 'exec') return c def dis(x=None): """Disassemble classes, methods, functions, or code. With no argument, disassemble the last traceback. """ if x is None: distb() return if hasattr(x, '__func__'): # Method x = x.__func__ if hasattr(x, '__code__'): # Function x = x.__code__ if hasattr(x, '__dict__'): # Class or module items = sorted(x.__dict__.items()) for name, x1 in items: if isinstance(x1, _have_code): print("Disassembly of %s:" % name) try: dis(x1) except TypeError as msg: print("Sorry:", msg) print() elif hasattr(x, 'co_code'): # Code object disassemble(x) elif isinstance(x, (bytes, bytearray)): # Raw bytecode _disassemble_bytes(x) elif isinstance(x, str): # Source code _disassemble_str(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 tb is None: 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) # The inspect module interrogates this dictionary to build its # list of CO_* constants. It is also used by pretty_flags to # turn the co_flags field into a human readable list. COMPILER_FLAG_NAMES = { 1: "OPTIMIZED", 2: "NEWLOCALS", 4: "VARARGS", 8: "VARKEYWORDS", 16: "NESTED", 32: "GENERATOR", 64: "NOFREE", } def pretty_flags(flags): """Return pretty representation of code flags.""" names = [] for i in range(32): flag = 1<<i if flags & flag: names.append(COMPILER_FLAG_NAMES.get(flag, hex(flag))) flags ^= flag if not flags: break else: names.append(hex(flags)) return ", ".join(names) def code_info(x): """Formatted details of methods, functions, or code.""" if hasattr(x, '__func__'): # Method x = x.__func__ if hasattr(x, '__code__'): # Function x = x.__code__ if isinstance(x, str): # Source code x = _try_compile(x, "<code_info>") if hasattr(x, 'co_code'): # Code object return _format_code_info(x) else: raise TypeError("don't know how to disassemble %s objects" % type(x).__name__) def _format_code_info(co): lines = [] lines.append("Name: %s" % co.co_name) lines.append("Filename: %s" % co.co_filename) lines.append("Argument count: %s" % co.co_argcount) lines.append("Kw-only arguments: %s" % co.co_kwonlyargcount) lines.append("Number of locals: %s" % co.co_nlocals) lines.append("Stack size: %s" % co.co_stacksize) lines.append("Flags: %s" % pretty_flags(co.co_flags)) if co.co_consts: lines.append("Constants:") for i_c in enumerate(co.co_consts): lines.append("%4d: %r" % i_c) if co.co_names: lines.append("Names:") for i_n in enumerate(co.co_names): lines.append("%4d: %s" % i_n) if co.co_varnames: lines.append("Variable names:") for i_n in enumerate(co.co_varnames): lines.append("%4d: %s" % i_n) if co.co_freevars: lines.append("Free variables:") for i_n in enumerate(co.co_freevars): lines.append("%4d: %s" % i_n) if co.co_cellvars: lines.append("Cell variables:") for i_n in enumerate(co.co_cellvars): lines.append("%4d: %s" % i_n) return "\n".join(lines) def show_code(co): """Print details of methods, functions, or code to stdout.""" print(code_info(co)) def disassemble(co, lasti=-1): """Disassemble a code object.""" code = co.co_code labels = findlabels(code) linestarts = dict(findlinestarts(co)) n = len(code) i = 0 extended_arg = 0 free = None while i < n: op = code[i] if i in linestarts: if i > 0: print() print("%3d" % linestarts[i], end=' ') else: print(' ', end=' ') if i == lasti: print('-->', end=' ') else: print(' ', end=' ') if i in labels: print('>>', end=' ') else: print(' ', end=' ') print(repr(i).rjust(4), end=' ') print(opname[op].ljust(20), end=' ') i = i+1 if op >= HAVE_ARGUMENT: oparg = code[i] + code[i+1]*256 + extended_arg extended_arg = 0 i = i+2 if op == EXTENDED_ARG: extended_arg = oparg*65536 print(repr(oparg).rjust(5), end=' ') if op in hasconst: print('(' + repr(co.co_consts[oparg]) + ')', end=' ') elif op in hasname: print('(' + co.co_names[oparg] + ')', end=' ') elif op in hasjrel: print('(to ' + repr(i + oparg) + ')', end=' ') elif op in haslocal: print('(' + co.co_varnames[oparg] + ')', end=' ') elif op in hascompare: print('(' + cmp_op[oparg] + ')', end=' ') elif op in hasfree: if free is None: free = co.co_cellvars + co.co_freevars print('(' + free[oparg] + ')', end=' ') elif op in hasnargs: print('(%d positional, %d keyword pair)' % (code[i-2], code[i-1]), end=' ') print() def _disassemble_bytes(code, lasti=-1, varnames=None, names=None, constants=None): labels = findlabels(code) n = len(code) i = 0 while i < n: op = code[i] if i == lasti: print('-->', end=' ') else: print(' ', end=' ') if i in labels: print('>>', end=' ') else: print(' ', end=' ') print(repr(i).rjust(4), end=' ') print(opname[op].ljust(15), end=' ') i = i+1 if op >= HAVE_ARGUMENT: oparg = code[i] + code[i+1]*256 i = i+2 print(repr(oparg).rjust(5), end=' ') if op in hasconst: if constants: print('(' + repr(constants[oparg]) + ')', end=' ') else: print('(%d)'%oparg, end=' ') elif op in hasname: if names is not None: print('(' + names[oparg] + ')', end=' ') else: print('(%d)'%oparg, end=' ') elif op in hasjrel: print('(to ' + repr(i + oparg) + ')', end=' ') elif op in haslocal: if varnames: print('(' + varnames[oparg] + ')', end=' ') else: print('(%d)' % oparg, end=' ') elif op in hascompare: print('(' + cmp_op[oparg] + ')', end=' ') elif op in hasnargs: print('(%d positional, %d keyword pair)' % (code[i-2], code[i-1]), end=' ') print() def _disassemble_str(source): """Compile the source string, then disassemble the code object.""" disassemble(_try_compile(source, '<dis>')) 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: op = code[i] i = i+1 if op >= HAVE_ARGUMENT: oparg = code[i] + 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 def findlinestarts(code): """Find the offsets in a byte code which are start of lines in the source. Generate pairs (offset, lineno) as described in Python/compile.c. """ byte_increments = list(code.co_lnotab[0::2]) line_increments = list(code.co_lnotab[1::2]) lastlineno = None lineno = code.co_firstlineno addr = 0 for byte_incr, line_incr in zip(byte_increments, line_increments): if byte_incr: if lineno != lastlineno: yield (addr, lineno) lastlineno = lineno addr += byte_incr lineno += line_incr if lineno != lastlineno: yield (addr, lineno) 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 fn is None: f = sys.stdin else: f = open(fn) source = f.read() if fn is not None: f.close() else: fn = "<stdin>" code = compile(source, fn, "exec") dis(code) if __name__ == "__main__": _test()