# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1098989245 -7200
# Node ID 668cb12070c27bb56b8c5118501122449e2d1c68
# Parent  ba40e828e2eb73bd75b28a7236ac3745a887b183
Added proper support for integers, longs, floats and doubles, along with
constant value retrieval.
Added a bytecode processing module.

diff -r ba40e828e2eb -r 668cb12070c2 bytecode.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/bytecode.py	Thu Oct 28 20:47:25 2004 +0200
@@ -0,0 +1,240 @@
+#!/usr/bin/env python
+
+"""
+Java bytecode conversion. Specification found at the following URL:
+http://java.sun.com/docs/books/vmspec/2nd-edition/html/Instructions2.doc.html
+"""
+
+import dis # for access to Python bytecode values
+
+# Bytecode conversion.
+
+def get_instructions(code):
+    global java_bytecodes
+
+    i = 0
+    instructions = []
+    while i < len(code):
+        bytecode = ord(code[i])
+        mnemonic, number_of_arguments, stack_change = java_bytecodes[bytecode]
+
+        # NOTE: To be fixed.
+        if number_of_arguments is None:
+            print "Stop at", mnemonic
+            return instructions
+
+        arguments = []
+        for j in range(0, number_of_arguments):
+            arguments.append(ord(code[i + 1 + j]))
+
+        i = i + 1 + number_of_arguments
+        instructions.append((mnemonic, arguments))
+
+    return instructions
+
+java_bytecodes = {
+    # code : (mnemonic, number of following bytes, change in stack)
+    0 : ("nop", 0, 0),
+    1 : ("aconst_null", 0, 1),
+    2 : ("iconst_m1", 0, 1),
+    3 : ("iconst_0", 0, 1),
+    4 : ("iconst_1", 0, 1),
+    5 : ("iconst_2", 0, 1),
+    6 : ("iconst_3", 0, 1),
+    7 : ("iconst_4", 0, 1),
+    8 : ("iconst_5", 0, 1),
+    9 : ("lconst_0", 0, 1),
+    10 : ("lconst_1", 0, 1),
+    11 : ("fconst_0", 0, 1),
+    12 : ("fconst_1", 0, 1),
+    13 : ("fconst_2", 0, 1),
+    14 : ("dconst_0", 0, 1),
+    15 : ("dconst_1", 0, 1),
+    16 : ("bipush", 1, 1),
+    17 : ("sipush", 2, 1),
+    18 : ("ldc", 1, 1),
+    19 : ("ldc_w", 2, 1),
+    20 : ("ldc2_w", 2, 1),
+    21 : ("iload", 1, 1),
+    22 : ("lload", 1, 1),
+    23 : ("fload", 1, 1),
+    24 : ("dload", 1, 1),
+    25 : ("aload", 1, 1),
+    26 : ("iload_0", 0, 1),
+    27 : ("iload_1", 0, 1),
+    28 : ("iload_2", 0, 1),
+    29 : ("iload_3", 0, 1),
+    30 : ("lload_0", 0, 1),
+    31 : ("lload_1", 0, 1),
+    32 : ("lload_2", 0, 1),
+    33 : ("lload_3", 0, 1),
+    34 : ("fload_0", 0, 1),
+    35 : ("fload_1", 0, 1),
+    36 : ("fload_2", 0, 1),
+    37 : ("fload_3", 0, 1),
+    38 : ("dload_0", 0, 1),
+    39 : ("dload_1", 0, 1),
+    40 : ("dload_2", 0, 1),
+    41 : ("dload_3", 0, 1),
+    42 : ("aload_0", 0, 1),
+    43 : ("aload_1", 0, 1),
+    44 : ("aload_2", 0, 1),
+    45 : ("aload_3", 0, 1),
+    46 : ("iaload", 0, -1),
+    47 : ("laload", 0, -1),
+    48 : ("faload", 0, -1),
+    49 : ("daload", 0, -1),
+    50 : ("aaload", 0, -1),
+    51 : ("baload", 0, -1),
+    52 : ("caload", 0, -1),
+    53 : ("saload", 0, -1),
+    54 : ("istore", 1, -1),
+    55 : ("lstore", 1, -1),
+    56 : ("fstore", 1, -1),
+    57 : ("dstore", 1, -1),
+    58 : ("astore", 1, -1),
+    59 : ("istore_0", 0, -1),
+    60 : ("istore_1", 0, -1),
+    61 : ("istore_2", 0, -1),
+    62 : ("istore_3", 0, -1),
+    63 : ("lstore_0", 0, -1),
+    64 : ("lstore_1", 0, -1),
+    65 : ("lstore_2", 0, -1),
+    66 : ("lstore_3", 0, -1),
+    67 : ("fstore_0", 0, -1),
+    68 : ("fstore_1", 0, -1),
+    69 : ("fstore_2", 0, -1),
+    70 : ("fstore_3", 0, -1),
+    71 : ("dstore_0", 0, -1),
+    72 : ("dstore_1", 0, -1),
+    73 : ("dstore_2", 0, -1),
+    74 : ("dstore_3", 0, -1),
+    75 : ("astore_0", 0, -1),
+    76 : ("astore_1", 0, -1),
+    77 : ("astore_2", 0, -1),
+    78 : ("astore_3", 0, -1),
+    79 : ("iastore", 0, -3),
+    80 : ("lastore", 0, -3),
+    81 : ("fastore", 0, -3),
+    82 : ("dastore", 0, -3),
+    83 : ("aastore", 0, -3),
+    84 : ("bastore", 0, -3),
+    85 : ("castore", 0, -3),
+    86 : ("sastore", 0, -3),
+    87 : ("pop", 0, -1),
+    88 : ("pop2", 0, None), # variable number of elements removed
+    89 : ("dup", 0, 1),
+    90 : ("dup_x1", 0, 1),
+    91 : ("dup_x2", 0, 1),
+    92 : ("dup2", 0, 2), # or 1 extra stack value
+    93 : ("dup2_x1", 0, 2), # or 1 extra stack value
+    94 : ("dup2_x2", 0, 2), # or 1 extra stack value
+    95 : ("swap", 0, 0),
+    96 : ("iadd", 0, -1),
+    97 : ("ladd", 0, -1),
+    98 : ("fadd", 0, -1),
+    99 : ("dadd", 0, -1),
+    100 : ("isub", 0, -1),
+    101 : ("lsub", 0, -1),
+    102 : ("fsub", 0, -1),
+    103 : ("dsub", 0, -1),
+    104 : ("imul", 0, -1),
+    105 : ("lmul", 0, -1),
+    106 : ("fmul", 0, -1),
+    107 : ("dmul", 0, -1),
+    108 : ("idiv", 0, -1),
+    109 : ("ldiv", 0, -1),
+    110 : ("fdiv", 0, -1),
+    111 : ("ddiv", 0, -1),
+    112 : ("irem", 0, -1),
+    113 : ("lrem", 0, -1),
+    114 : ("frem", 0, -1),
+    115 : ("drem", 0, -1),
+    116 : ("ineg", 0, 0),
+    117 : ("lneg", 0, 0),
+    118 : ("fneg", 0, 0),
+    119 : ("dneg", 0, 0),
+    120 : ("ishl", 0, -1),
+    121 : ("lshl", 0, -1),
+    122 : ("ishr", 0, -1),
+    123 : ("lshr", 0, -1),
+    124 : ("iushr", 0, -1),
+    125 : ("lushr", 0, -1),
+    126 : ("iand", 0, -1),
+    127 : ("land", 0, -1),
+    128 : ("ior", 0, -1),
+    129 : ("lor", 0, -1),
+    130 : ("ixor", 0, -1),
+    131 : ("lxor", 0, -1),
+    132 : ("iinc", 2, 0),
+    133 : ("i2l", 0, 0),
+    134 : ("i2f", 0, 0),
+    135 : ("i2d", 0, 0),
+    136 : ("l2i", 0, 0),
+    137 : ("l2f", 0, 0),
+    138 : ("l2d", 0, 0),
+    139 : ("f2i", 0, 0),
+    140 : ("f2l", 0, 0),
+    141 : ("f2d", 0, 0),
+    142 : ("d2i", 0, 0),
+    143 : ("d2l", 0, 0),
+    144 : ("d2f", 0, 0),
+    145 : ("i2b", 0, 0),
+    146 : ("i2c", 0, 0),
+    147 : ("i2s", 0, 0),
+    148 : ("lcmp", 0, -1),
+    149 : ("fcmpl", 0, -1),
+    150 : ("fcmpg", 0, -1),
+    151 : ("dcmpl", 0, -1),
+    152 : ("dcmpg", 0, -1),
+    153 : ("ifeq", 2, -1),
+    154 : ("ifne", 2, -1),
+    155 : ("iflt", 2, -1),
+    156 : ("ifge", 2, -1),
+    157 : ("ifgt", 2, -1),
+    158 : ("ifle", 2, -1),
+    159 : ("if_icmpeq", 2, -2),
+    160 : ("if_icmpne", 2, -2),
+    161 : ("if_icmplt", 2, -2),
+    162 : ("if_icmpge", 2, -2),
+    163 : ("if_icmpgt", 2, -2),
+    164 : ("if_icmple", 2, -2),
+    165 : ("if_acmpeq", 2, -2),
+    166 : ("if_acmpne", 2, -2),
+    167 : ("goto", 2, 0),
+    168 : ("jsr", 2, 1),
+    169 : ("ret", 1, 0),
+    170 : ("tableswitch", None, -1), # variable number of arguments
+    171 : ("lookupswitch", None, -1), # variable number of arguments
+    172 : ("ireturn", 0, -1),
+    173 : ("lreturn", 0, -1),
+    174 : ("freturn", 0, -1),
+    175 : ("dreturn", 0, -1),
+    176 : ("areturn", 0, -1),
+    177 : ("return", 0, 0),
+    178 : ("getstatic", 2, 1),
+    179 : ("putstatic", 2, -1),
+    180 : ("getfield", 2, 0),
+    181 : ("putfield", 2, -2),
+    182 : ("invokevirtual", 2, None), # variable number of elements removed
+    183 : ("invokespecial", 2, None), # variable number of elements removed
+    184 : ("invokestatic", 2, None), # variable number of elements removed
+    185 : ("invokeinterface", 4, None), # variable number of elements removed
+    187 : ("new", 2, 1),
+    188 : ("newarray", 1, 0),
+    189 : ("anewarray", 2, 0),
+    190 : ("arraylength", 0, 0),
+    191 : ("athrow", 0, 0),
+    192 : ("checkcast", 2, 0),
+    193 : ("instanceof", 2, 0),
+    194 : ("monitorenter", 0, -1),
+    195 : ("monitorexit", 0, -1),
+    196 : ("wide", None, None), # 3 or 5 arguments, stack changes according to modified element
+    197 : ("multianewarray", 3, None), # variable number of elements removed
+    198 : ("ifnull", 2, -1),
+    199 : ("ifnonnull", 2, -1),
+    200 : ("goto_w", 4, 0),
+    201 : ("jsr_w", 4, 1),
+    }
+
+# vim: tabstop=4 expandtab shiftwidth=4
diff -r ba40e828e2eb -r 668cb12070c2 classfile.py
--- a/classfile.py	Thu Oct 28 16:38:33 2004 +0200
+++ b/classfile.py	Thu Oct 28 20:47:25 2004 +0200
@@ -5,7 +5,7 @@
 http://java.sun.com/docs/books/vmspec/2nd-edition/html/ClassFile.doc.html
 """
 
-import struct
+import struct # for general decoding of class files
 
 # Utility functions.
 
@@ -18,6 +18,18 @@
 def u4(data):
     return struct.unpack(">L", data[0:4])[0]
 
+def s4(data):
+    return struct.unpack(">l", data[0:4])[0]
+
+def s8(data):
+    return struct.unpack(">q", data[0:8])[0]
+
+def f4(data):
+    return struct.unpack(">f", data[0:4])[0]
+
+def f8(data):
+    return struct.unpack(">d", data[0:8])[0]
+
 # Useful mix-ins.
 
 class NameUtils:
@@ -82,14 +94,16 @@
 class SmallNumInfo:
     def init(self, data, class_file):
         self.class_file = class_file
-        self.bytes = u4(data[0:4])
+        self.bytes = data[0:4]
         return data[4:]
 
 class IntegerInfo(SmallNumInfo):
-    pass
+    def get_value(self):
+        return s4(self.bytes)
 
 class FloatInfo(SmallNumInfo):
-    pass
+    def get_value(self):
+        return f4(self.bytes)
 
 class LargeNumInfo:
     def init(self, data, class_file):
@@ -99,10 +113,12 @@
         return data[8:]
 
 class LongInfo(LargeNumInfo):
-    pass
+    def get_value(self):
+        return s8(self.high_bytes + self.low_bytes)
 
 class DoubleInfo(LargeNumInfo):
-    pass
+    def get_value(self):
+        return f8(self.high_bytes + self.low_bytes)
 
 # Other information.
 # Objects of these classes are generally aware of the class they reside in.
@@ -195,11 +211,15 @@
 
 class ConstantValueAttributeInfo(AttributeInfo):
     def init(self, data, class_file):
+        self.class_file = class_file
         self.attribute_length = u4(data[0:4])
         self.constant_value_index = u2(data[4:6])
         assert 4+self.attribute_length == 6
         return data[4+self.attribute_length:]
 
+    def get_value(self):
+        return self.class_file.constants[self.constant_value_index - 1].get_value()
+
 class CodeAttributeInfo(AttributeInfo):
     def init(self, data, class_file):
         self.class_file = class_file