llvm-project/lldb/test/functionalities/data-formatter/data-formatter-python-synth/StdVectorSynthProvider.py

56 lines
2.2 KiB
Python

class StdVectorSynthProvider:
def __init__(self, valobj, dict):
self.valobj = valobj;
self.update()
def num_children(self):
start_val = self.start.GetValueAsUnsigned(0)
finish_val = self.finish.GetValueAsUnsigned(0)
end_val = self.end.GetValueAsUnsigned(0)
# Before a vector has been constructed, it will contain bad values
# so we really need to be careful about the length we return since
# unitialized data can cause us to return a huge number. We need
# to also check for any of the start, finish or end of storage values
# being zero (NULL). If any are, then this vector has not been
# initialized yet and we should return zero
# Make sure nothing is NULL
if start_val == 0 or finish_val == 0 or end_val == 0:
return 0
# Make sure start is less than finish
if start_val >= finish_val:
return 0
# Make sure finish is less than or equal to end of storage
if finish_val > end_val:
return 0
# We might still get things wrong, so cap things at 256 items for now
# TODO: read a target "settings set" variable for this to allow it to
# be customized
num_children = (finish_val-start_val)/self.data_size
if num_children > 256:
return 256
return num_children
def get_child_index(self,name):
if name == "len":
return self.num_children();
else:
return int(name.lstrip('[').rstrip(']'))
def get_child_at_index(self,index):
if index == self.num_children():
return self.valobj.CreateValueFromExpression("len",str(self.num_children()))
else:
offset = index * self.data_size
return self.start.CreateChildAtOffset('['+str(index)+']',offset,self.data_type)
def update(self):
impl = self.valobj.GetChildMemberWithName('_M_impl')
self.start = impl.GetChildMemberWithName('_M_start')
self.finish = impl.GetChildMemberWithName('_M_finish')
self.end = impl.GetChildMemberWithName('_M_end_of_storage')
self.data_type = self.start.GetType().GetPointeeType()
self.data_size = self.data_type.GetByteSize()