src/etc/gdb_providers.py

   1 from sys import version_info
   2
   3 import gdb
   4
   5 if version_info[0] >= 3:
   6     xrange = range
   7
   8 ZERO_FIELD = "__0"
   9 FIRST_FIELD = "__1"
  10
  11
  12 def unwrap_unique_or_non_null(unique_or_nonnull):
  13     # BACKCOMPAT: rust 1.32
  14     # https://github.com/rust-lang/rust/commit/7a0911528058e87d22ea305695f4047572c5e067
  15     # BACKCOMPAT: rust 1.60
  16     # https://github.com/rust-lang/rust/commit/2a91eeac1a2d27dd3de1bf55515d765da20fd86f
  17     ptr = unique_or_nonnull["pointer"]
  18     return ptr if ptr.type.code == gdb.TYPE_CODE_PTR else ptr[ptr.type.fields()[0]]
  19
  20
  21 class EnumProvider:
  22     def __init__(self, valobj):
  23         content = valobj[valobj.type.fields()[0]]
  24         fields = content.type.fields()
  25         self.empty = len(fields) == 0
  26         if not self.empty:
  27             if len(fields) == 1:
  28                 discriminant = 0
  29             else:
  30                 discriminant = int(content[fields[0]]) + 1
  31             self.active_variant = content[fields[discriminant]]
  32             self.name = fields[discriminant].name
  33             self.full_name = "{}::{}".format(valobj.type.name, self.name)
  34         else:
  35             self.full_name = valobj.type.name
  36
  37     def to_string(self):
  38         return self.full_name
  39
  40     def children(self):
  41         if not self.empty:
  42             yield self.name, self.active_variant
  43
  44
  45 class StdStringProvider:
  46     def __init__(self, valobj):
  47         self.valobj = valobj
  48         vec = valobj["vec"]
  49         self.length = int(vec["len"])
  50         self.data_ptr = unwrap_unique_or_non_null(vec["buf"]["ptr"])
  51
  52     def to_string(self):
  53         return self.data_ptr.lazy_string(encoding="utf-8", length=self.length)
  54
  55     @staticmethod
  56     def display_hint():
  57         return "string"
  58
  59
  60 class StdOsStringProvider:
  61     def __init__(self, valobj):
  62         self.valobj = valobj
  63         buf = self.valobj["inner"]["inner"]
  64         is_windows = "Wtf8Buf" in buf.type.name
  65         vec = buf[ZERO_FIELD] if is_windows else buf
  66
  67         self.length = int(vec["len"])
  68         self.data_ptr = unwrap_unique_or_non_null(vec["buf"]["ptr"])
  69
  70     def to_string(self):
  71         return self.data_ptr.lazy_string(encoding="utf-8", length=self.length)
  72
  73     def display_hint(self):
  74         return "string"
  75
  76
  77 class StdStrProvider:
  78     def __init__(self, valobj):
  79         self.valobj = valobj
  80         self.length = int(valobj["length"])
  81         self.data_ptr = valobj["data_ptr"]
  82
  83     def to_string(self):
  84         return self.data_ptr.lazy_string(encoding="utf-8", length=self.length)
  85
  86     @staticmethod
  87     def display_hint():
  88         return "string"
  89
  90 def _enumerate_array_elements(element_ptrs):
  91     for (i, element_ptr) in enumerate(element_ptrs):
  92         key = "[{}]".format(i)
  93         element = element_ptr.dereference()
  94
  95         try:
  96             # rust-lang/rust#64343: passing deref expr to `str` allows
  97             # catching exception on garbage pointer
  98             str(element)
  99         except RuntimeError:
 100             yield key, "inaccessible"
 101
 102             break
 103
 104         yield key, element
 105
 106 class StdSliceProvider:
 107     def __init__(self, valobj):
 108         self.valobj = valobj
 109         self.length = int(valobj["length"])
 110         self.data_ptr = valobj["data_ptr"]
 111
 112     def to_string(self):
 113         return "{}(size={})".format(self.valobj.type, self.length)
 114
 115     def children(self):
 116         return _enumerate_array_elements(
 117             self.data_ptr + index for index in xrange(self.length)
 118         )
 119
 120     @staticmethod
 121     def display_hint():
 122         return "array"
 123
 124 class StdVecProvider:
 125     def __init__(self, valobj):
 126         self.valobj = valobj
 127         self.length = int(valobj["len"])
 128         self.data_ptr = unwrap_unique_or_non_null(valobj["buf"]["ptr"])
 129
 130     def to_string(self):
 131         return "Vec(size={})".format(self.length)
 132
 133     def children(self):
 134         return _enumerate_array_elements(
 135             self.data_ptr + index for index in xrange(self.length)
 136         )
 137
 138     @staticmethod
 139     def display_hint():
 140         return "array"
 141
 142
 143 class StdVecDequeProvider:
 144     def __init__(self, valobj):
 145         self.valobj = valobj
 146         self.head = int(valobj["head"])
 147         self.size = int(valobj["len"])
 148         self.cap = int(valobj["buf"]["cap"])
 149         self.data_ptr = unwrap_unique_or_non_null(valobj["buf"]["ptr"])
 150
 151     def to_string(self):
 152         return "VecDeque(size={})".format(self.size)
 153
 154     def children(self):
 155         return _enumerate_array_elements(
 156             (self.data_ptr + ((self.head + index) % self.cap)) for index in xrange(self.size)
 157         )
 158
 159     @staticmethod
 160     def display_hint():
 161         return "array"
 162
 163
 164 class StdRcProvider:
 165     def __init__(self, valobj, is_atomic=False):
 166         self.valobj = valobj
 167         self.is_atomic = is_atomic
 168         self.ptr = unwrap_unique_or_non_null(valobj["ptr"])
 169         self.value = self.ptr["data" if is_atomic else "value"]
 170         self.strong = self.ptr["strong"]["v" if is_atomic else "value"]["value"]
 171         self.weak = self.ptr["weak"]["v" if is_atomic else "value"]["value"] - 1
 172
 173     def to_string(self):
 174         if self.is_atomic:
 175             return "Arc(strong={}, weak={})".format(int(self.strong), int(self.weak))
 176         else:
 177             return "Rc(strong={}, weak={})".format(int(self.strong), int(self.weak))
 178
 179     def children(self):
 180         yield "value", self.value
 181         yield "strong", self.strong
 182         yield "weak", self.weak
 183
 184
 185 class StdCellProvider:
 186     def __init__(self, valobj):
 187         self.value = valobj["value"]["value"]
 188
 189     def to_string(self):
 190         return "Cell"
 191
 192     def children(self):
 193         yield "value", self.value
 194
 195
 196 class StdRefProvider:
 197     def __init__(self, valobj):
 198         self.value = valobj["value"].dereference()
 199         self.borrow = valobj["borrow"]["borrow"]["value"]["value"]
 200
 201     def to_string(self):
 202         borrow = int(self.borrow)
 203         if borrow >= 0:
 204             return "Ref(borrow={})".format(borrow)
 205         else:
 206             return "Ref(borrow_mut={})".format(-borrow)
 207
 208     def children(self):
 209         yield "*value", self.value
 210         yield "borrow", self.borrow
 211
 212
 213 class StdRefCellProvider:
 214     def __init__(self, valobj):
 215         self.value = valobj["value"]["value"]
 216         self.borrow = valobj["borrow"]["value"]["value"]
 217
 218     def to_string(self):
 219         borrow = int(self.borrow)
 220         if borrow >= 0:
 221             return "RefCell(borrow={})".format(borrow)
 222         else:
 223             return "RefCell(borrow_mut={})".format(-borrow)
 224
 225     def children(self):
 226         yield "value", self.value
 227         yield "borrow", self.borrow
 228
 229
 230 class StdNonZeroNumberProvider:
 231     def __init__(self, valobj):
 232         fields = valobj.type.fields()
 233         assert len(fields) == 1
 234         field = list(fields)[0]
 235         self.value = str(valobj[field.name])
 236
 237     def to_string(self):
 238         return self.value
 239
 240
 241 # Yields children (in a provider's sense of the word) for a BTreeMap.
 242 def children_of_btree_map(map):
 243     # Yields each key/value pair in the node and in any child nodes.
 244     def children_of_node(node_ptr, height):
 245         def cast_to_internal(node):
 246             internal_type_name = node.type.target().name.replace("LeafNode", "InternalNode", 1)
 247             internal_type = gdb.lookup_type(internal_type_name)
 248             return node.cast(internal_type.pointer())
 249
 250         if node_ptr.type.name.startswith("alloc::collections::btree::node::BoxedNode<"):
 251             # BACKCOMPAT: rust 1.49
 252             node_ptr = node_ptr["ptr"]
 253         node_ptr = unwrap_unique_or_non_null(node_ptr)
 254         leaf = node_ptr.dereference()
 255         keys = leaf["keys"]
 256         vals = leaf["vals"]
 257         edges = cast_to_internal(node_ptr)["edges"] if height > 0 else None
 258         length = leaf["len"]
 259
 260         for i in xrange(0, length + 1):
 261             if height > 0:
 262                 child_ptr = edges[i]["value"]["value"]
 263                 for child in children_of_node(child_ptr, height - 1):
 264                     yield child
 265             if i < length:
 266                 # Avoid "Cannot perform pointer math on incomplete type" on zero-sized arrays.
 267                 key_type_size = keys.type.sizeof
 268                 val_type_size = vals.type.sizeof
 269                 key = keys[i]["value"]["value"] if key_type_size > 0 else gdb.parse_and_eval("()")
 270                 val = vals[i]["value"]["value"] if val_type_size > 0 else gdb.parse_and_eval("()")
 271                 yield key, val
 272
 273     if map["length"] > 0:
 274         root = map["root"]
 275         if root.type.name.startswith("core::option::Option<"):
 276             root = root.cast(gdb.lookup_type(root.type.name[21:-1]))
 277         node_ptr = root["node"]
 278         height = root["height"]
 279         for child in children_of_node(node_ptr, height):
 280             yield child
 281
 282
 283 class StdBTreeSetProvider:
 284     def __init__(self, valobj):
 285         self.valobj = valobj
 286
 287     def to_string(self):
 288         return "BTreeSet(size={})".format(self.valobj["map"]["length"])
 289
 290     def children(self):
 291         inner_map = self.valobj["map"]
 292         for i, (child, _) in enumerate(children_of_btree_map(inner_map)):
 293             yield "[{}]".format(i), child
 294
 295     @staticmethod
 296     def display_hint():
 297         return "array"
 298
 299
 300 class StdBTreeMapProvider:
 301     def __init__(self, valobj):
 302         self.valobj = valobj
 303
 304     def to_string(self):
 305         return "BTreeMap(size={})".format(self.valobj["length"])
 306
 307     def children(self):
 308         for i, (key, val) in enumerate(children_of_btree_map(self.valobj)):
 309             yield "key{}".format(i), key
 310             yield "val{}".format(i), val
 311
 312     @staticmethod
 313     def display_hint():
 314         return "map"
 315
 316
 317 # BACKCOMPAT: rust 1.35
 318 class StdOldHashMapProvider:
 319     def __init__(self, valobj, show_values=True):
 320         self.valobj = valobj
 321         self.show_values = show_values
 322
 323         self.table = self.valobj["table"]
 324         self.size = int(self.table["size"])
 325         self.hashes = self.table["hashes"]
 326         self.hash_uint_type = self.hashes.type
 327         self.hash_uint_size = self.hashes.type.sizeof
 328         self.modulo = 2 ** self.hash_uint_size
 329         self.data_ptr = self.hashes[ZERO_FIELD]["pointer"]
 330
 331         self.capacity_mask = int(self.table["capacity_mask"])
 332         self.capacity = (self.capacity_mask + 1) % self.modulo
 333
 334         marker = self.table["marker"].type
 335         self.pair_type = marker.template_argument(0)
 336         self.pair_type_size = self.pair_type.sizeof
 337
 338         self.valid_indices = []
 339         for idx in range(self.capacity):
 340             data_ptr = self.data_ptr.cast(self.hash_uint_type.pointer())
 341             address = data_ptr + idx
 342             hash_uint = address.dereference()
 343             hash_ptr = hash_uint[ZERO_FIELD]["pointer"]
 344             if int(hash_ptr) != 0:
 345                 self.valid_indices.append(idx)
 346
 347     def to_string(self):
 348         if self.show_values:
 349             return "HashMap(size={})".format(self.size)
 350         else:
 351             return "HashSet(size={})".format(self.size)
 352
 353     def children(self):
 354         start = int(self.data_ptr) & ~1
 355
 356         hashes = self.hash_uint_size * self.capacity
 357         align = self.pair_type_size
 358         len_rounded_up = (((((hashes + align) % self.modulo - 1) % self.modulo) & ~(
 359                 (align - 1) % self.modulo)) % self.modulo - hashes) % self.modulo
 360
 361         pairs_offset = hashes + len_rounded_up
 362         pairs_start = gdb.Value(start + pairs_offset).cast(self.pair_type.pointer())
 363
 364         for index in range(self.size):
 365             table_index = self.valid_indices[index]
 366             idx = table_index & self.capacity_mask
 367             element = (pairs_start + idx).dereference()
 368             if self.show_values:
 369                 yield "key{}".format(index), element[ZERO_FIELD]
 370                 yield "val{}".format(index), element[FIRST_FIELD]
 371             else:
 372                 yield "[{}]".format(index), element[ZERO_FIELD]
 373
 374     def display_hint(self):
 375         return "map" if self.show_values else "array"
 376
 377
 378 class StdHashMapProvider:
 379     def __init__(self, valobj, show_values=True):
 380         self.valobj = valobj
 381         self.show_values = show_values
 382
 383         table = self.table()
 384         table_inner = table["table"]
 385         capacity = int(table_inner["bucket_mask"]) + 1
 386         ctrl = table_inner["ctrl"]["pointer"]
 387
 388         self.size = int(table_inner["items"])
 389         self.pair_type = table.type.template_argument(0).strip_typedefs()
 390
 391         self.new_layout = not table_inner.type.has_key("data")
 392         if self.new_layout:
 393             self.data_ptr = ctrl.cast(self.pair_type.pointer())
 394         else:
 395             self.data_ptr = table_inner["data"]["pointer"]
 396
 397         self.valid_indices = []
 398         for idx in range(capacity):
 399             address = ctrl + idx
 400             value = address.dereference()
 401             is_presented = value & 128 == 0
 402             if is_presented:
 403                 self.valid_indices.append(idx)
 404
 405     def table(self):
 406         if self.show_values:
 407             hashbrown_hashmap = self.valobj["base"]
 408         elif self.valobj.type.fields()[0].name == "map":
 409             # BACKCOMPAT: rust 1.47
 410             # HashSet wraps std::collections::HashMap, which wraps hashbrown::HashMap
 411             hashbrown_hashmap = self.valobj["map"]["base"]
 412         else:
 413             # HashSet wraps hashbrown::HashSet, which wraps hashbrown::HashMap
 414             hashbrown_hashmap = self.valobj["base"]["map"]
 415         return hashbrown_hashmap["table"]
 416
 417     def to_string(self):
 418         if self.show_values:
 419             return "HashMap(size={})".format(self.size)
 420         else:
 421             return "HashSet(size={})".format(self.size)
 422
 423     def children(self):
 424         pairs_start = self.data_ptr
 425
 426         for index in range(self.size):
 427             idx = self.valid_indices[index]
 428             if self.new_layout:
 429                 idx = -(idx + 1)
 430             element = (pairs_start + idx).dereference()
 431             if self.show_values:
 432                 yield "key{}".format(index), element[ZERO_FIELD]
 433                 yield "val{}".format(index), element[FIRST_FIELD]
 434             else:
 435                 yield "[{}]".format(index), element[ZERO_FIELD]
 436
 437     def display_hint(self):
 438         return "map" if self.show_values else "array"