blob: 57bbf0f76ac9893f1cfe462848603f7c3a060b34 [file] [log] [blame]
# Synthetic children provider example for class MaskedData
# to use me:
# command script import ./ --allow-reload
# type synthetic add MaskedData --python-class
# example.MaskedData_SyntheticChildrenProvider
class MaskedData_SyntheticChildrenProvider:
def __init__(self, valobj, dict):
# remember the SBValue since you will not have another chance to get it
# :-)
self.valobj = valobj
def num_children(self):
# you could perform calculations involving the SBValue and/or its children to determine this value
# here, we have an hardcoded value - but since you have stored the SBValue you could use it to
# help figure out the correct thing to return here. if you return a number N, you should be prepared to
# answer questions about N children
return 4
def has_children(self):
# we simply say True here because we know we have 4 children
# in general, you want to make this calculation as simple as possible
# and return True if in doubt (you can always return num_children == 0
# later)
return True
def get_child_index(self, name):
# given a name, return its index
# you can return None if you don't know the answer for a given name
if name == "value":
return 0
# here, we are using a reserved C++ keyword as a child name - we could not do that in the source code
# but we are free to use the names we like best in the synthetic children provider class
# we are also not respecting the order of declaration in the C++ class itself - as long as
# we are consistent, we can do that freely
if name == "operator":
return 1
if name == "mask":
return 2
# this member does not exist in the original class - we will compute its value and show it to the user
# when returning synthetic children, there is no need to only stick to
# what already exists in memory
if name == "apply()":
return 3
return None # no clue, just say none
def get_child_at_index(self, index):
# precautionary measures
if index < 0:
return None
if index > self.num_children():
return None
if self.valobj.IsValid() == False:
return None
if index == 0:
return self.valobj.GetChildMemberWithName("value")
if index == 1:
# fetch the value of the operator
op_chosen = self.valobj.GetChildMemberWithName(
# if it is a known value, return a descriptive string for it
# we are not doing this in the most efficient possible way, but the code is very readable
# and easy to maintain - if you change the values on the C++ side,
# the same changes must be made here
if op_chosen == 0:
return self.valobj.CreateValueFromExpression(
"operator", '(const char*)"none"')
elif op_chosen == 1:
return self.valobj.CreateValueFromExpression(
"operator", '(const char*)"AND"')
elif op_chosen == 2:
return self.valobj.CreateValueFromExpression(
"operator", '(const char*)"OR"')
elif op_chosen == 3:
return self.valobj.CreateValueFromExpression(
"operator", '(const char*)"XOR"')
elif op_chosen == 4:
return self.valobj.CreateValueFromExpression(
"operator", '(const char*)"NAND"')
elif op_chosen == 5:
return self.valobj.CreateValueFromExpression(
"operator", '(const char*)"NOR"')
return self.valobj.CreateValueFromExpression(
"operator", '(const char*)"unknown"') # something else
if index == 2:
return self.valobj.GetChildMemberWithName("mask")
if index == 3:
# for this, we must fetch all the other elements
# in an efficient implementation, we would be caching this data for
# efficiency
value = self.valobj.GetChildMemberWithName(
operator = self.valobj.GetChildMemberWithName(
mask = self.valobj.GetChildMemberWithName(
# compute the masked value according to the operator
if operator == 1:
value = value & mask
elif operator == 2:
value = value | mask
elif operator == 3:
value = value ^ mask
elif operator == 4:
value = ~(value & mask)
elif operator == 5:
value = ~(value | mask)
value &= 0xFFFFFFFF # make sure Python does not extend our values to 64-bits
# return it - again, not the most efficient possible way. we should actually be pushing the computed value
# into an SBData, and using the SBData to create an SBValue - this
# has the advantage of readability
return self.valobj.CreateValueFromExpression(
"apply()", '(uint32_t)(' + str(value) + ')')
def update(self):
# we do not do anything special in update - but this would be the right place to lookup
# the data we use in get_child_at_index and cache it