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gerrit-public.fairphone.software / platform / prebuilts / rust / 2a86e42b929441ea78a3d82ceef48234ce3128ea / . / linux-x86 / 1.36.0 / lib / rustlib / etc / lldb_rust_formatters.py
blob: fdc1c4fa0cc38d95d0f74e324b596dbcec729347 [file] [log] [blame]
Matthew Maurerbd398542019-09-05 16:25:08 -0700[diff] [blame]1import lldb
2import re
3import debugger_pretty_printers_common as rustpp
4
5#===============================================================================
6# LLDB Pretty Printing Module for Rust
7#===============================================================================
8
9class LldbType(rustpp.Type):
10
11 def __init__(self, ty):
12 super(LldbType, self).__init__()
13 self.ty = ty
14 self.fields = None
15
16 def get_unqualified_type_name(self):
17 qualified_name = self.ty.GetName()
18
19 if qualified_name is None:
20 return qualified_name
21
22 return rustpp.extract_type_name(qualified_name).replace("&'static ", "&")
23
24 def get_dwarf_type_kind(self):
25 type_class = self.ty.GetTypeClass()
26
27 if type_class == lldb.eTypeClassStruct:
28 return rustpp.DWARF_TYPE_CODE_STRUCT
29
30 if type_class == lldb.eTypeClassUnion:
31 return rustpp.DWARF_TYPE_CODE_UNION
32
33 if type_class == lldb.eTypeClassPointer:
34 return rustpp.DWARF_TYPE_CODE_PTR
35
36 if type_class == lldb.eTypeClassArray:
37 return rustpp.DWARF_TYPE_CODE_ARRAY
38
39 if type_class == lldb.eTypeClassEnumeration:
40 return rustpp.DWARF_TYPE_CODE_ENUM
41
42 return None
43
44 def get_fields(self):
45 assert ((self.get_dwarf_type_kind() == rustpp.DWARF_TYPE_CODE_STRUCT) or
46 (self.get_dwarf_type_kind() == rustpp.DWARF_TYPE_CODE_UNION))
47 if self.fields is None:
48 self.fields = list(self.ty.fields)
49 return self.fields
50
51 def get_wrapped_value(self):
52 return self.ty
53
54
55class LldbValue(rustpp.Value):
56 def __init__(self, lldb_val):
57 ty = lldb_val.type
58 wty = LldbType(ty)
59 super(LldbValue, self).__init__(wty)
60 self.lldb_val = lldb_val
61 self.children = {}
62
63 def get_child_at_index(self, index):
64 child = self.children.get(index)
65 if child is None:
66 lldb_field = self.lldb_val.GetChildAtIndex(index)
67 child = LldbValue(lldb_field)
68 self.children[index] = child
69 return child
70
71 def as_integer(self):
72 return self.lldb_val.GetValueAsUnsigned()
73
74 def get_wrapped_value(self):
75 return self.lldb_val
76
77
78def print_val(lldb_val, internal_dict):
79 val = LldbValue(lldb_val)
80 type_kind = val.type.get_type_kind()
81
82 if (type_kind == rustpp.TYPE_KIND_REGULAR_STRUCT or
83 type_kind == rustpp.TYPE_KIND_REGULAR_UNION or
84 type_kind == rustpp.TYPE_KIND_EMPTY):
85 return print_struct_val(val,
86 internal_dict,
87 omit_first_field = False,
88 omit_type_name = False,
89 is_tuple_like = False)
90
91 if type_kind == rustpp.TYPE_KIND_STRUCT_VARIANT:
92 return print_struct_val(val,
93 internal_dict,
94 omit_first_field = True,
95 omit_type_name = False,
96 is_tuple_like = False)
97
98 if type_kind == rustpp.TYPE_KIND_SLICE:
99 return print_vec_slice_val(val, internal_dict)
100
101 if type_kind == rustpp.TYPE_KIND_STR_SLICE:
102 return print_str_slice_val(val, internal_dict)
103
104 if type_kind == rustpp.TYPE_KIND_STD_VEC:
105 return print_std_vec_val(val, internal_dict)
106
107 if type_kind == rustpp.TYPE_KIND_STD_STRING:
108 return print_std_string_val(val, internal_dict)
109
110 if type_kind == rustpp.TYPE_KIND_TUPLE:
111 return print_struct_val(val,
112 internal_dict,
113 omit_first_field = False,
114 omit_type_name = True,
115 is_tuple_like = True)
116
117 if type_kind == rustpp.TYPE_KIND_TUPLE_STRUCT:
118 return print_struct_val(val,
119 internal_dict,
120 omit_first_field = False,
121 omit_type_name = False,
122 is_tuple_like = True)
123
124 if type_kind == rustpp.TYPE_KIND_CSTYLE_VARIANT:
125 return val.type.get_unqualified_type_name()
126
127 if type_kind == rustpp.TYPE_KIND_TUPLE_VARIANT:
128 return print_struct_val(val,
129 internal_dict,
130 omit_first_field = True,
131 omit_type_name = False,
132 is_tuple_like = True)
133
134 if type_kind == rustpp.TYPE_KIND_SINGLETON_ENUM:
135 return print_val(lldb_val.GetChildAtIndex(0), internal_dict)
136
137 if type_kind == rustpp.TYPE_KIND_PTR:
138 return print_pointer_val(val, internal_dict)
139
140 if type_kind == rustpp.TYPE_KIND_FIXED_SIZE_VEC:
141 return print_fixed_size_vec_val(val, internal_dict)
142
143 if type_kind == rustpp.TYPE_KIND_REGULAR_ENUM:
144 # This is a regular enum, extract the discriminant
145 discriminant_val = rustpp.get_discriminant_value_as_integer(val)
146 return print_val(lldb_val.GetChildAtIndex(discriminant_val), internal_dict)
147
148 if type_kind == rustpp.TYPE_KIND_COMPRESSED_ENUM:
149 encoded_enum_info = rustpp.EncodedEnumInfo(val)
150 if encoded_enum_info.is_null_variant():
151 return encoded_enum_info.get_null_variant_name()
152
153 non_null_val = encoded_enum_info.get_non_null_variant_val()
154 return print_val(non_null_val.get_wrapped_value(), internal_dict)
155
156 # No pretty printer has been found
157 return lldb_val.GetValue()
158
159
160#=--------------------------------------------------------------------------------------------------
161# Type-Specialized Printing Functions
162#=--------------------------------------------------------------------------------------------------
163
164def print_struct_val(val, internal_dict, omit_first_field, omit_type_name, is_tuple_like):
165 """
166 Prints a struct, tuple, or tuple struct value with Rust syntax.
167 Ignores any fields before field_start_index.
168 """
169 assert (val.type.get_dwarf_type_kind() == rustpp.DWARF_TYPE_CODE_STRUCT or
170 val.type.get_dwarf_type_kind() == rustpp.DWARF_TYPE_CODE_UNION)
171
172 if omit_type_name:
173 type_name = ""
174 else:
175 type_name = val.type.get_unqualified_type_name()
176
177 if is_tuple_like:
178 template = "%(type_name)s(%(body)s)"
179 separator = ", "
180 else:
181 template = "%(type_name)s {\n%(body)s\n}"
182 separator = ", \n"
183
184 fields = val.type.get_fields()
185
186 def render_child(child_index):
187 this = ""
188 if not is_tuple_like:
189 field_name = fields[child_index].name
190 this += field_name + ": "
191
192 field_val = val.get_child_at_index(child_index)
193
194 if not field_val.get_wrapped_value().IsValid():
195 field = fields[child_index]
196 # LLDB is not good at handling zero-sized values, so we have to help
197 # it a little
198 if field.GetType().GetByteSize() == 0:
199 return this + rustpp.extract_type_name(field.GetType().GetName())
200 else:
201 return this + "<invalid value>"
202
203 return this + print_val(field_val.get_wrapped_value(), internal_dict)
204
205 if omit_first_field:
206 field_start_index = 1
207 else:
208 field_start_index = 0
209
210 body = separator.join([render_child(idx) for idx in range(field_start_index, len(fields))])
211
212 return template % {"type_name": type_name,
213 "body": body}
214
215def print_pointer_val(val, internal_dict):
216 """Prints a pointer value with Rust syntax"""
217 assert val.type.get_dwarf_type_kind() == rustpp.DWARF_TYPE_CODE_PTR
218 sigil = "&"
219 type_name = val.type.get_unqualified_type_name()
220 if type_name and type_name[0:1] in ["&", "*"]:
221 sigil = type_name[0:1]
222
223 return sigil + hex(val.as_integer())
224
225
226def print_fixed_size_vec_val(val, internal_dict):
227 assert val.type.get_dwarf_type_kind() == rustpp.DWARF_TYPE_CODE_ARRAY
228 lldb_val = val.get_wrapped_value()
229
230 output = "["
231
232 for i in range(lldb_val.num_children):
233 output += print_val(lldb_val.GetChildAtIndex(i), internal_dict)
234 if i != lldb_val.num_children - 1:
235 output += ", "
236
237 output += "]"
238 return output
239
240
241def print_vec_slice_val(val, internal_dict):
242 (length, data_ptr) = rustpp.extract_length_and_ptr_from_slice(val)
243 return "&[%s]" % print_array_of_values(val.get_wrapped_value().GetName(),
244 data_ptr,
245 length,
246 internal_dict)
247
248
249def print_std_vec_val(val, internal_dict):
250 (length, data_ptr, cap) = rustpp.extract_length_ptr_and_cap_from_std_vec(val)
251 return "vec![%s]" % print_array_of_values(val.get_wrapped_value().GetName(),
252 data_ptr,
253 length,
254 internal_dict)
255
256def print_str_slice_val(val, internal_dict):
257 (length, data_ptr) = rustpp.extract_length_and_ptr_from_slice(val)
258 return read_utf8_string(data_ptr, length)
259
260def print_std_string_val(val, internal_dict):
261 vec = val.get_child_at_index(0)
262 (length, data_ptr, cap) = rustpp.extract_length_ptr_and_cap_from_std_vec(vec)
263 return read_utf8_string(data_ptr, length)
264
265#=--------------------------------------------------------------------------------------------------
266# Helper Functions
267#=--------------------------------------------------------------------------------------------------
268
269def print_array_of_values(array_name, data_ptr_val, length, internal_dict):
270 """Prints a contiguous memory range, interpreting it as values of the
271 pointee-type of data_ptr_val."""
272
273 data_ptr_type = data_ptr_val.type
274 assert data_ptr_type.get_dwarf_type_kind() == rustpp.DWARF_TYPE_CODE_PTR
275
276 element_type = data_ptr_type.get_wrapped_value().GetPointeeType()
277 element_type_size = element_type.GetByteSize()
278
279 start_address = data_ptr_val.as_integer()
280 raw_value = data_ptr_val.get_wrapped_value()
281
282 def render_element(i):
283 address = start_address + i * element_type_size
284 element_val = raw_value.CreateValueFromAddress(array_name + ("[%s]" % i),
285 address,
286 element_type)
287 return print_val(element_val, internal_dict)
288
289 return ', '.join([render_element(i) for i in range(length)])
290
291
292def read_utf8_string(ptr_val, byte_count):
293 if byte_count == 0:
294 return '""'
295 error = lldb.SBError()
296 process = ptr_val.get_wrapped_value().GetProcess()
297 data = process.ReadMemory(ptr_val.as_integer(), byte_count, error)
298 if error.Success():
299 return '"%s"' % data.decode(encoding='UTF-8')
300 else:
301 return '<error: %s>' % error.GetCString()