diff options
Diffstat (limited to 'python/lldbutils/lldbutils/general.py')
| -rw-r--r-- | python/lldbutils/lldbutils/general.py | 165 |
1 files changed, 165 insertions, 0 deletions
diff --git a/python/lldbutils/lldbutils/general.py b/python/lldbutils/lldbutils/general.py new file mode 100644 index 0000000000..577b3847fa --- /dev/null +++ b/python/lldbutils/lldbutils/general.py @@ -0,0 +1,165 @@ +# Any copyright is dedicated to the Public Domain. +# http://creativecommons.org/publicdomain/zero/1.0/ + +import lldb + +from lldbutils import utils + + +def summarize_string(valobj, internal_dict): + data = valobj.GetChildMemberWithName("mData") + length = valobj.GetChildMemberWithName("mLength").GetValueAsUnsigned(0) + return utils.format_string(data, length) + + +def summarize_atom(valobj, internal_dict): + target = lldb.debugger.GetSelectedTarget() + length = valobj.GetChildMemberWithName("mLength").GetValueAsUnsigned() + string = target.EvaluateExpression( + "(char16_t*)%s.GetUTF16String()" % valobj.GetName() + ) + return utils.format_string(string, length) + + +class TArraySyntheticChildrenProvider: + def __init__(self, valobj, internal_dict): + self.valobj = valobj + self.header = self.valobj.GetChildMemberWithName("mHdr") + self.element_type = self.valobj.GetType().GetTemplateArgumentType(0) + self.element_size = self.element_type.GetByteSize() + header_size = self.header.GetType().GetPointeeType().GetByteSize() + self.element_base_addr = self.header.GetValueAsUnsigned(0) + header_size + + def num_children(self): + return ( + self.header.Dereference() + .GetChildMemberWithName("mLength") + .GetValueAsUnsigned(0) + ) + + def get_child_index(self, name): + try: + index = int(name) + if index >= self.num_children(): + return None + # Ideally we'd use the exception type, but it's unclear what that is + # without knowing how to trigger the original exception. + except: # NOQA: E501, E722 + pass + return None + + def get_child_at_index(self, index): + if index >= self.num_children(): + return None + addr = self.element_base_addr + index * self.element_size + return self.valobj.CreateValueFromAddress( + "[%d]" % index, addr, self.element_type + ) + + +def prefcnt(debugger, command, result, dict): + """Displays the refcount of an object.""" + # We handled regular nsISupports-like refcounted objects and cycle collected + # objects. + target = debugger.GetSelectedTarget() + process = target.GetProcess() + thread = process.GetSelectedThread() + frame = thread.GetSelectedFrame() + obj = frame.EvaluateExpression(command) + if obj.GetError().Fail(): + print("could not evaluate expression") + return + obj = utils.dereference(obj) + field = obj.GetChildMemberWithName("mRefCnt") + if field.GetError().Fail(): + field = obj.GetChildMemberWithName("refCnt") + if field.GetError().Fail(): + print("not a refcounted object") + return + refcnt_type = field.GetType().GetCanonicalType().GetName() + if refcnt_type == "nsAutoRefCnt": + print(field.GetChildMemberWithName("mValue").GetValueAsUnsigned(0)) + elif refcnt_type == "nsCycleCollectingAutoRefCnt": + print( + field.GetChildMemberWithName("mRefCntAndFlags").GetValueAsUnsigned(0) >> 2 + ) + elif refcnt_type == "mozilla::ThreadSafeAutoRefCnt": + print( + field.GetChildMemberWithName("mValue") + .GetChildMemberWithName("mValue") + .GetValueAsUnsigned(0) + ) + elif refcnt_type == "int": # non-atomic mozilla::RefCounted object + print(field.GetValueAsUnsigned(0)) + elif refcnt_type == "mozilla::Atomic<int>": # atomic mozilla::RefCounted object + print(field.GetChildMemberWithName("mValue").GetValueAsUnsigned(0)) + else: + print("unknown mRefCnt type " + refcnt_type) + + +# Used to work around http://llvm.org/bugs/show_bug.cgi?id=22211 +def callfunc(debugger, command, result, dict): + """Calls a function for which debugger information is unavailable by getting its address + from the symbol table. The function is assumed to return void.""" + + if "(" not in command: + print("Usage: callfunc your_function(args)") + return + + command_parts = command.split("(") + funcname = command_parts[0].strip() + args = command_parts[1] + + target = debugger.GetSelectedTarget() + symbols = target.FindFunctions(funcname).symbols + if not symbols: + print('Could not find a function symbol for a function called "%s"' % funcname) + return + + sym = symbols[0] + arg_types = "()" + if sym.name and sym.name.startswith(funcname + "("): + arg_types = sym.name[len(funcname) :] + debugger.HandleCommand( + "print ((void(*)%s)0x%0x)(%s" + % (arg_types, sym.addr.GetLoadAddress(target), args) + ) + + +def init(debugger): + debugger.HandleCommand( + "type summary add nsAString -F lldbutils.general.summarize_string" + ) + debugger.HandleCommand( + "type summary add nsACString -F lldbutils.general.summarize_string" + ) + debugger.HandleCommand( + "type summary add nsFixedString -F lldbutils.general.summarize_string" + ) + debugger.HandleCommand( + "type summary add nsFixedCString -F lldbutils.general.summarize_string" + ) + debugger.HandleCommand( + "type summary add nsAutoString -F lldbutils.general.summarize_string" + ) + debugger.HandleCommand( + "type summary add nsAutoCString -F lldbutils.general.summarize_string" + ) + debugger.HandleCommand( + "type summary add nsAtom -F lldbutils.general.summarize_atom" + ) + debugger.HandleCommand( + 'type synthetic add -x "nsTArray<" -l lldbutils.general.TArraySyntheticChildrenProvider' + ) + debugger.HandleCommand( + 'type synthetic add -x "AutoTArray<" -l lldbutils.general.TArraySyntheticChildrenProvider' # NOQA: E501 + ) + debugger.HandleCommand( + 'type synthetic add -x "FallibleTArray<" -l lldbutils.general.TArraySyntheticChildrenProvider' # NOQA: E501 + ) + debugger.HandleCommand( + "command script add -f lldbutils.general.prefcnt -f lldbutils.general.prefcnt prefcnt" + ) + debugger.HandleCommand( + "command script add -f lldbutils.general.callfunc -f lldbutils.general.callfunc callfunc" + ) |