data/gdb/mono-gdb.py

   1 #
   2 # Author: Zoltan Varga (vargaz@gmail.com)
   3 # License: MIT/X11
   4 #
   5
   6 #
   7 # This is a mono support mode for gdb 7.0 and later
   8 # Usage:
   9 # - copy/symlink this file to the directory where the mono executable lives.
  10 # - run mono under gdb, or attach to a mono process started with --debug=gdb using gdb.
  11 #
  12
  13 from __future__ import print_function
  14 import os
  15
  16 class StringPrinter:
  17     "Print a C# string"
  18
  19     def __init__(self, val):
  20         self.val = val
  21
  22     def to_string(self):
  23         if int(self.val.cast (gdb.lookup_type ("guint64"))) == 0:
  24             return "null"
  25
  26         obj = self.val.cast (gdb.lookup_type ("MonoString").pointer ()).dereference ()
  27         len = obj ['length']
  28         chars = obj ['chars']
  29         i = 0
  30         res = ['"']
  31         while i < len:
  32             val = (chars.cast(gdb.lookup_type ("gint64")) + (i * 2)).cast(gdb.lookup_type ("gunichar2").pointer ()).dereference ()
  33             if val >= 256:
  34                 c = unichr (val)
  35             else:
  36                 c = chr (val)
  37             res.append (c)
  38             i = i + 1
  39         res.append ('"')
  40         return ''.join (res)
  41
  42 def stringify_class_name(ns, name):
  43     if ns == "System":
  44         if name == "Byte":
  45             return "byte"
  46         if name == "String":
  47             return "string"
  48     if ns == "":
  49         return name
  50     else:
  51         return "{}.{}".format (ns, name)
  52
  53 class ArrayPrinter:
  54     "Print a C# array"
  55
  56     def __init__(self, val, class_ns, class_name):
  57         self.val = val
  58         self.class_ns = class_ns
  59         self.class_name = class_name
  60
  61     def to_string(self):
  62         obj = self.val.cast (gdb.lookup_type ("MonoArray").pointer ()).dereference ()
  63         length = obj ['max_length']
  64         return "{} [{}]".format (stringify_class_name (self.class_ns, self.class_name [0:len(self.class_name) - 2]), int(length))
  65
  66 class ObjectPrinter:
  67     "Print a C# object"
  68
  69     def __init__(self, val):
  70         if str(val.type)[-1] == "&":
  71             self.val = val.address.cast (gdb.lookup_type ("MonoObject").pointer ())
  72         else:
  73             self.val = val.cast (gdb.lookup_type ("MonoObject").pointer ())
  74
  75     class _iterator:
  76         def __init__(self,obj):
  77             self.obj = obj
  78             self.iter = self.obj.type.fields ().__iter__ ()
  79             pass
  80
  81         def __iter__(self):
  82             return self
  83
  84         def next(self):
  85             field = self.iter.next ()
  86             try:
  87                 if str(self.obj [field.name].type) == "object":
  88                     # Avoid recursion
  89                     return (field.name, self.obj [field.name].cast (gdb.lookup_type ("void").pointer ()))
  90                 else:
  91                     return (field.name, self.obj [field.name])
  92             except:
  93                 # Superclass
  94                 return (field.name, self.obj.cast (gdb.lookup_type ("{}".format (field.name))))
  95
  96     def children(self):
  97         # FIXME: It would be easier if gdb.Value would support iteration itself
  98         # It would also be better if we could return None
  99         if int(self.val.cast (gdb.lookup_type ("guint64"))) == 0:
 100             return {}.__iter__ ()
 101         try:
 102             obj = self.val.dereference ()
 103             class_ns = obj ['vtable'].dereference ()['klass'].dereference ()['name_space'].string ()
 104             class_name = obj ['vtable'].dereference ()['klass'].dereference ()['name'].string ()
 105             if class_name [-2:len(class_name)] == "[]":
 106                 return {}.__iter__ ()
 107             try:
 108                 gdb_type = gdb.lookup_type ("struct {}_{}".format (class_ns.replace (".", "_"), class_name))
 109                 return self._iterator(obj.cast (gdb_type))
 110             except:
 111                 return {}.__iter__ ()
 112         except:
 113             print (sys.exc_info ()[0])
 114             print (sys.exc_info ()[1])
 115             return {}.__iter__ ()
 116
 117     def to_string(self):
 118         if int(self.val.cast (gdb.lookup_type ("guint64"))) == 0:
 119             return "null"
 120         try:
 121             obj = self.val.dereference ()
 122             class_ns = obj ['vtable'].dereference ()['klass'].dereference ()['name_space'].string ()
 123             class_name = obj ['vtable'].dereference ()['klass'].dereference ()['name'].string ()
 124             if class_ns == "System" and class_name == "String":
 125                 return StringPrinter (self.val).to_string ()
 126             if class_name [-2:len(class_name)] == "[]":
 127                 return ArrayPrinter (self.val,class_ns,class_name).to_string ()
 128             if class_ns != "":
 129                 try:
 130                     gdb_type = gdb.lookup_type ("struct {}.{}".format (class_ns, class_name))
 131                 except:
 132                     # Maybe there is no debug info for that type
 133                     return "{}.{}".format (class_ns, class_name)
 134                 #return obj.cast (gdb_type)
 135                 return "{}.{}".format (class_ns, class_name)
 136             return class_name
 137         except:
 138             print (sys.exc_info ()[0])
 139             print (sys.exc_info ()[1])
 140             # FIXME: This can happen because we don't have liveness information
 141             return self.val.cast (gdb.lookup_type ("guint64"))
 142
 143 class MonoMethodPrinter:
 144     "Print a MonoMethod structure"
 145
 146     def __init__(self, val):
 147         self.val = val
 148
 149     def to_string(self):
 150         if int(self.val.cast (gdb.lookup_type ("guint64"))) == 0:
 151             return "0x0"
 152         val = self.val.dereference ()
 153         klass = val ["klass"].dereference ()
 154         class_name = stringify_class_name (klass ["name_space"].string (), klass ["name"].string ())
 155         return "\"{}:{} ()\"".format (class_name, val ["name"].string ())
 156         # This returns more info but requires calling into the inferior
 157         #return "\"{}\"".format (gdb.parse_and_eval ("mono_method_full_name ({}, 1)".format (str (int (self.val.cast (gdb.lookup_type ("guint64")))))).string ())
 158
 159 class MonoClassPrinter:
 160     "Print a MonoClass structure"
 161
 162     def __init__(self, val):
 163         self.val = val
 164
 165     def to_string_inner(self, add_quotes):
 166         if int(self.val.cast (gdb.lookup_type ("guint64"))) == 0:
 167             return "0x0"
 168         klass = self.val.dereference ()
 169         class_name = stringify_class_name (klass ["name_space"].string (), klass ["name"].string ())
 170         if add_quotes:
 171             return "\"{}\"".format (class_name)
 172         else:
 173             return class_name
 174         # This returns more info but requires calling into the inferior
 175         #return "\"{}\"".format (gdb.parse_and_eval ("mono_type_full_name (&((MonoClass*){})->byval_arg)".format (str (int ((self.val).cast (gdb.lookup_type ("guint64")))))))
 176
 177     def to_string(self):
 178         try:
 179             return self.to_string_inner (True)
 180         except:
 181             #print (sys.exc_info ()[0])
 182             #print (sys.exc_info ()[1])
 183             return str(self.val.cast (gdb.lookup_type ("gpointer")))
 184
 185 class MonoGenericInstPrinter:
 186     "Print a MonoGenericInst structure"
 187
 188     def __init__(self, val):
 189         self.val = val
 190
 191     def to_string(self):
 192         if int(self.val.cast (gdb.lookup_type ("guint64"))) == 0:
 193             return "0x0"
 194         inst = self.val.dereference ()
 195         inst_len = inst ["type_argc"]
 196         inst_args = inst ["type_argv"]
 197         inst_str = ""
 198         for i in range(0, inst_len):
 199             # print (inst_args)
 200             type_printer = MonoTypePrinter (inst_args [i])
 201             if i > 0:
 202                 inst_str = inst_str + ", "
 203             inst_str = inst_str + type_printer.to_string ()
 204         return inst_str
 205
 206 class MonoGenericClassPrinter:
 207     "Print a MonoGenericClass structure"
 208
 209     def __init__(self, val):
 210         self.val = val
 211
 212     def to_string_inner(self):
 213         gclass = self.val.dereference ()
 214         container_str = str(gclass ["container_class"])
 215         class_inst = gclass ["context"]["class_inst"]
 216         class_inst_str = ""
 217         if int(class_inst.cast (gdb.lookup_type ("guint64"))) != 0:
 218             class_inst_str  = str(class_inst)
 219         method_inst = gclass ["context"]["method_inst"]
 220         method_inst_str = ""
 221         if int(method_inst.cast (gdb.lookup_type ("guint64"))) != 0:
 222             method_inst_str  = str(method_inst)
 223         return "{}, [{}], [{}]>".format (container_str, class_inst_str, method_inst_str)
 224
 225     def to_string(self):
 226         try:
 227             return self.to_string_inner ()
 228         except:
 229             #print (sys.exc_info ()[0])
 230             #print (sys.exc_info ()[1])
 231             return str(self.val.cast (gdb.lookup_type ("gpointer")))
 232
 233 class MonoTypePrinter:
 234     "Print a MonoType structure"
 235
 236     def __init__(self, val):
 237         self.val = val
 238
 239     def to_string_inner(self, csharp):
 240         try:
 241             t = self.val.referenced_value ()
 242
 243             kind = str (t ["type"]).replace ("MONO_TYPE_", "").lower ()
 244             info = ""
 245
 246             if kind == "class":
 247                 p = MonoClassPrinter(t ["data"]["klass"])
 248                 info = p.to_string ()
 249             elif kind == "genericinst":
 250                 info = str(t ["data"]["generic_class"])
 251
 252             if info != "":
 253                 return "{{{}, {}}}".format (kind, info)
 254             else:
 255                 return "{{{}}}".format (kind)
 256         except:
 257             #print (sys.exc_info ()[0])
 258             #print (sys.exc_info ()[1])
 259             return str(self.val.cast (gdb.lookup_type ("gpointer")))
 260
 261     def to_string(self):
 262         return self.to_string_inner (False)
 263
 264 class MonoMethodRgctxPrinter:
 265     "Print a MonoMethodRgctx structure"
 266
 267     def __init__(self, val):
 268         self.val = val
 269
 270     def to_string(self):
 271         rgctx = self.val.dereference ()
 272         klass = rgctx ["class_vtable"].dereference () ["klass"]
 273         klass_printer = MonoClassPrinter (klass)
 274         inst = rgctx ["method_inst"].dereference ()
 275         inst_len = inst ["type_argc"]
 276         inst_args = inst ["type_argv"]
 277         inst_str = ""
 278         for i in range(0, inst_len):
 279             # print (inst_args)
 280             type_printer = MonoTypePrinter (inst_args [i])
 281             if i > 0:
 282                 inst_str = inst_str + ", "
 283             inst_str = inst_str + type_printer.to_string ()
 284         return "MRGCTX[{}, [{}]]".format (klass_printer.to_string(), inst_str)
 285
 286 class MonoVTablePrinter:
 287     "Print a MonoVTable structure"
 288
 289     def __init__(self, val):
 290         self.val = val
 291
 292     def to_string(self):
 293         if int(self.val.cast (gdb.lookup_type ("guint64"))) == 0:
 294             return "0x0"
 295         vtable = self.val.dereference ()
 296         klass = vtable ["klass"]
 297         klass_printer = MonoClassPrinter (klass)
 298
 299         return "vtable({})".format (klass_printer.to_string ())
 300
 301 def lookup_pretty_printer(val):
 302     t = str (val.type)
 303     if t == "object":
 304         return ObjectPrinter (val)
 305     if t[0:5] == "class" and t[-1] == "&":
 306         return ObjectPrinter (val)
 307     if t == "string":
 308         return StringPrinter (val)
 309     if t == "MonoString *":
 310         return StringPrinter (val)
 311     if t == "MonoMethod *":
 312         return MonoMethodPrinter (val)
 313     if t == "MonoClass *":
 314         return MonoClassPrinter (val)
 315     if t == "MonoType *":
 316         return MonoTypePrinter (val)
 317     if t == "MonoGenericInst *":
 318         return MonoGenericInstPrinter (val)
 319     if t == "MonoGenericClass *":
 320         return MonoGenericClassPrinter (val)
 321     if t == "MonoMethodRuntimeGenericContext *":
 322         return MonoMethodRgctxPrinter (val)
 323     if t == "MonoVTable *":
 324         return MonoVTablePrinter (val)
 325     return None
 326
 327 def register_csharp_printers(obj):
 328     "Register C# pretty-printers with objfile Obj."
 329
 330     if obj == None:
 331         obj = gdb
 332
 333     obj.pretty_printers.append (lookup_pretty_printer)
 334
 335 # This command will flush the debugging info collected by the runtime
 336 class XdbCommand (gdb.Command):
 337     def __init__ (self):
 338         super (XdbCommand, self).__init__ ("xdb", gdb.COMMAND_NONE,
 339                                            gdb.COMPLETE_COMMAND)
 340
 341     def invoke(self, arg, from_tty):
 342         gdb.execute ("call mono_xdebug_flush ()")
 343
 344 register_csharp_printers (gdb.current_objfile())
 345
 346 XdbCommand ()
 347
 348 gdb.execute ("set environment MONO_XDEBUG gdb")
 349
 350 print ("Mono support loaded.")
 351
 352