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.tail = int(valobj["tail"])
 148         self.cap = int(valobj["buf"]["cap"])
 149         self.data_ptr = unwrap_unique_or_non_null(valobj["buf"]["ptr"])
 150         if self.head >= self.tail:
 151             self.size = self.head - self.tail
 152         else:
 153             self.size = self.cap + self.head - self.tail
 154
 155     def to_string(self):
 156         return "VecDeque(size={})".format(self.size)
 157
 158     def children(self):
 159         return _enumerate_array_elements(
 160             (self.data_ptr + ((self.tail + index) % self.cap)) for index in xrange(self.size)
 161         )
 162
 163     @staticmethod
 164     def display_hint():
 165         return "array"
 166
 167
 168 class StdRcProvider:
 169     def __init__(self, valobj, is_atomic=False):
 170         self.valobj = valobj
 171         self.is_atomic = is_atomic
 172         self.ptr = unwrap_unique_or_non_null(valobj["ptr"])
 173         self.value = self.ptr["data" if is_atomic else "value"]
 174         self.strong = self.ptr["strong"]["v" if is_atomic else "value"]["value"]
 175         self.weak = self.ptr["weak"]["v" if is_atomic else "value"]["value"] - 1
 176
 177     def to_string(self):
 178         if self.is_atomic:
 179             return "Arc(strong={}, weak={})".format(int(self.strong), int(self.weak))
 180         else:
 181             return "Rc(strong={}, weak={})".format(int(self.strong), int(self.weak))
 182
 183     def children(self):
 184         yield "value", self.value
 185         yield "strong", self.strong
 186         yield "weak", self.weak
 187
 188
 189 class StdCellProvider:
 190     def __init__(self, valobj):
 191         self.value = valobj["value"]["value"]
 192
 193     def to_string(self):
 194         return "Cell"
 195
 196     def children(self):
 197         yield "value", self.value
 198
 199
 200 class StdRefProvider:
 201     def __init__(self, valobj):
 202         self.value = valobj["value"].dereference()
 203         self.borrow = valobj["borrow"]["borrow"]["value"]["value"]
 204
 205     def to_string(self):
 206         borrow = int(self.borrow)
 207         if borrow >= 0:
 208             return "Ref(borrow={})".format(borrow)
 209         else:
 210             return "Ref(borrow_mut={})".format(-borrow)
 211
 212     def children(self):
 213         yield "*value", self.value
 214         yield "borrow", self.borrow
 215
 216
 217 class StdRefCellProvider:
 218     def __init__(self, valobj):
 219         self.value = valobj["value"]["value"]
 220         self.borrow = valobj["borrow"]["value"]["value"]
 221
 222     def to_string(self):
 223         borrow = int(self.borrow)
 224         if borrow >= 0:
 225             return "RefCell(borrow={})".format(borrow)
 226         else:
 227             return "RefCell(borrow_mut={})".format(-borrow)
 228
 229     def children(self):
 230         yield "value", self.value
 231         yield "borrow", self.borrow
 232
 233
 234 # Yields children (in a provider's sense of the word) for a BTreeMap.
 235 def children_of_btree_map(map):
 236     # Yields each key/value pair in the node and in any child nodes.
 237     def children_of_node(node_ptr, height):
 238         def cast_to_internal(node):
 239             internal_type_name = node.type.target().name.replace("LeafNode", "InternalNode", 1)
 240             internal_type = gdb.lookup_type(internal_type_name)
 241             return node.cast(internal_type.pointer())
 242
 243         if node_ptr.type.name.startswith("alloc::collections::btree::node::BoxedNode<"):
 244             # BACKCOMPAT: rust 1.49
 245             node_ptr = node_ptr["ptr"]
 246         node_ptr = unwrap_unique_or_non_null(node_ptr)
 247         leaf = node_ptr.dereference()
 248         keys = leaf["keys"]
 249         vals = leaf["vals"]
 250         edges = cast_to_internal(node_ptr)["edges"] if height > 0 else None
 251         length = leaf["len"]
 252
 253         for i in xrange(0, length + 1):
 254             if height > 0:
 255                 child_ptr = edges[i]["value"]["value"]
 256                 for child in children_of_node(child_ptr, height - 1):
 257                     yield child
 258             if i < length:
 259                 # Avoid "Cannot perform pointer math on incomplete type" on zero-sized arrays.
 260                 key_type_size = keys.type.sizeof
 261                 val_type_size = vals.type.sizeof
 262                 key = keys[i]["value"]["value"] if key_type_size > 0 else gdb.parse_and_eval("()")
 263                 val = vals[i]["value"]["value"] if val_type_size > 0 else gdb.parse_and_eval("()")
 264                 yield key, val
 265
 266     if map["length"] > 0:
 267         root = map["root"]
 268         if root.type.name.startswith("core::option::Option<"):
 269             root = root.cast(gdb.lookup_type(root.type.name[21:-1]))
 270         node_ptr = root["node"]
 271         height = root["height"]
 272         for child in children_of_node(node_ptr, height):
 273             yield child
 274
 275
 276 class StdBTreeSetProvider:
 277     def __init__(self, valobj):
 278         self.valobj = valobj
 279
 280     def to_string(self):
 281         return "BTreeSet(size={})".format(self.valobj["map"]["length"])
 282
 283     def children(self):
 284         inner_map = self.valobj["map"]
 285         for i, (child, _) in enumerate(children_of_btree_map(inner_map)):
 286             yield "[{}]".format(i), child
 287
 288     @staticmethod
 289     def display_hint():
 290         return "array"
 291
 292
 293 class StdBTreeMapProvider:
 294     def __init__(self, valobj):
 295         self.valobj = valobj
 296
 297     def to_string(self):
 298         return "BTreeMap(size={})".format(self.valobj["length"])
 299
 300     def children(self):
 301         for i, (key, val) in enumerate(children_of_btree_map(self.valobj)):
 302             yield "key{}".format(i), key
 303             yield "val{}".format(i), val
 304
 305     @staticmethod
 306     def display_hint():
 307         return "map"
 308
 309
 310 # BACKCOMPAT: rust 1.35
 311 class StdOldHashMapProvider:
 312     def __init__(self, valobj, show_values=True):
 313         self.valobj = valobj
 314         self.show_values = show_values
 315
 316         self.table = self.valobj["table"]
 317         self.size = int(self.table["size"])
 318         self.hashes = self.table["hashes"]
 319         self.hash_uint_type = self.hashes.type
 320         self.hash_uint_size = self.hashes.type.sizeof
 321         self.modulo = 2 ** self.hash_uint_size
 322         self.data_ptr = self.hashes[ZERO_FIELD]["pointer"]
 323
 324         self.capacity_mask = int(self.table["capacity_mask"])
 325         self.capacity = (self.capacity_mask + 1) % self.modulo
 326
 327         marker = self.table["marker"].type
 328         self.pair_type = marker.template_argument(0)
 329         self.pair_type_size = self.pair_type.sizeof
 330
 331         self.valid_indices = []
 332         for idx in range(self.capacity):
 333             data_ptr = self.data_ptr.cast(self.hash_uint_type.pointer())
 334             address = data_ptr + idx
 335             hash_uint = address.dereference()
 336             hash_ptr = hash_uint[ZERO_FIELD]["pointer"]
 337             if int(hash_ptr) != 0:
 338                 self.valid_indices.append(idx)
 339
 340     def to_string(self):
 341         if self.show_values:
 342             return "HashMap(size={})".format(self.size)
 343         else:
 344             return "HashSet(size={})".format(self.size)
 345
 346     def children(self):
 347         start = int(self.data_ptr) & ~1
 348
 349         hashes = self.hash_uint_size * self.capacity
 350         align = self.pair_type_size
 351         len_rounded_up = (((((hashes + align) % self.modulo - 1) % self.modulo) & ~(
 352                 (align - 1) % self.modulo)) % self.modulo - hashes) % self.modulo
 353
 354         pairs_offset = hashes + len_rounded_up
 355         pairs_start = gdb.Value(start + pairs_offset).cast(self.pair_type.pointer())
 356
 357         for index in range(self.size):
 358             table_index = self.valid_indices[index]
 359             idx = table_index & self.capacity_mask
 360             element = (pairs_start + idx).dereference()
 361             if self.show_values:
 362                 yield "key{}".format(index), element[ZERO_FIELD]
 363                 yield "val{}".format(index), element[FIRST_FIELD]
 364             else:
 365                 yield "[{}]".format(index), element[ZERO_FIELD]
 366
 367     def display_hint(self):
 368         return "map" if self.show_values else "array"
 369
 370
 371 class StdHashMapProvider:
 372     def __init__(self, valobj, show_values=True):
 373         self.valobj = valobj
 374         self.show_values = show_values
 375
 376         table = self.table()
 377         table_inner = table["table"]
 378         capacity = int(table_inner["bucket_mask"]) + 1
 379         ctrl = table_inner["ctrl"]["pointer"]
 380
 381         self.size = int(table_inner["items"])
 382         self.pair_type = table.type.template_argument(0).strip_typedefs()
 383
 384         self.new_layout = not table_inner.type.has_key("data")
 385         if self.new_layout:
 386             self.data_ptr = ctrl.cast(self.pair_type.pointer())
 387         else:
 388             self.data_ptr = table_inner["data"]["pointer"]
 389
 390         self.valid_indices = []
 391         for idx in range(capacity):
 392             address = ctrl + idx
 393             value = address.dereference()
 394             is_presented = value & 128 == 0
 395             if is_presented:
 396                 self.valid_indices.append(idx)
 397
 398     def table(self):
 399         if self.show_values:
 400             hashbrown_hashmap = self.valobj["base"]
 401         elif self.valobj.type.fields()[0].name == "map":
 402             # BACKCOMPAT: rust 1.47
 403             # HashSet wraps std::collections::HashMap, which wraps hashbrown::HashMap
 404             hashbrown_hashmap = self.valobj["map"]["base"]
 405         else:
 406             # HashSet wraps hashbrown::HashSet, which wraps hashbrown::HashMap
 407             hashbrown_hashmap = self.valobj["base"]["map"]
 408         return hashbrown_hashmap["table"]
 409
 410     def to_string(self):
 411         if self.show_values:
 412             return "HashMap(size={})".format(self.size)
 413         else:
 414             return "HashSet(size={})".format(self.size)
 415
 416     def children(self):
 417         pairs_start = self.data_ptr
 418
 419         for index in range(self.size):
 420             idx = self.valid_indices[index]
 421             if self.new_layout:
 422                 idx = -(idx + 1)
 423             element = (pairs_start + idx).dereference()
 424             if self.show_values:
 425                 yield "key{}".format(index), element[ZERO_FIELD]
 426                 yield "val{}".format(index), element[FIRST_FIELD]
 427             else:
 428                 yield "[{}]".format(index), element[ZERO_FIELD]
 429
 430     def display_hint(self):
 431         return "map" if self.show_values else "array"