llvm-project/lldb/source/Plugins/Language/ObjC/NSError.cpp

230 lines
7.4 KiB
C++

//===-- NSError.cpp ---------------------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// C Includes
// C++ Includes
// Other libraries and framework includes
#include "clang/AST/DeclCXX.h"
// Project includes
#include "Cocoa.h"
#include "lldb/Core/DataBufferHeap.h"
#include "lldb/Core/Error.h"
#include "lldb/Core/Stream.h"
#include "lldb/Core/ValueObject.h"
#include "lldb/Core/ValueObjectConstResult.h"
#include "lldb/DataFormatters/FormattersHelpers.h"
#include "lldb/Host/Endian.h"
#include "lldb/Symbol/ClangASTContext.h"
#include "lldb/Target/ObjCLanguageRuntime.h"
#include "lldb/Target/Target.h"
#include "lldb/Utility/ProcessStructReader.h"
#include "Plugins/Language/ObjC/NSString.h"
using namespace lldb;
using namespace lldb_private;
using namespace lldb_private::formatters;
static lldb::addr_t
DerefToNSErrorPointer (ValueObject& valobj)
{
CompilerType valobj_type(valobj.GetCompilerType());
Flags type_flags(valobj_type.GetTypeInfo());
if (type_flags.AllClear(eTypeHasValue))
{
if (valobj.IsBaseClass() && valobj.GetParent())
return valobj.GetParent()->GetValueAsUnsigned(LLDB_INVALID_ADDRESS);
}
else
{
lldb::addr_t ptr_value = valobj.GetValueAsUnsigned(LLDB_INVALID_ADDRESS);
if (type_flags.AllSet(eTypeIsPointer))
{
CompilerType pointee_type(valobj_type.GetPointeeType());
Flags pointee_flags(pointee_type.GetTypeInfo());
if (pointee_flags.AllSet(eTypeIsPointer))
{
if (ProcessSP process_sp = valobj.GetProcessSP())
{
Error error;
ptr_value = process_sp->ReadPointerFromMemory(ptr_value, error);
}
}
}
return ptr_value;
}
return LLDB_INVALID_ADDRESS;
}
bool
lldb_private::formatters::NSError_SummaryProvider (ValueObject& valobj, Stream& stream, const TypeSummaryOptions& options)
{
ProcessSP process_sp(valobj.GetProcessSP());
if (!process_sp)
return false;
lldb::addr_t ptr_value = DerefToNSErrorPointer(valobj);
if (ptr_value == LLDB_INVALID_ADDRESS)
return false;
size_t ptr_size = process_sp->GetAddressByteSize();
lldb::addr_t code_location = ptr_value + 2 * ptr_size;
lldb::addr_t domain_location = ptr_value + 3 * ptr_size;
Error error;
uint64_t code = process_sp->ReadUnsignedIntegerFromMemory(code_location, ptr_size, 0, error);
if (error.Fail())
return false;
lldb::addr_t domain_str_value = process_sp->ReadPointerFromMemory(domain_location, error);
if (error.Fail() || domain_str_value == LLDB_INVALID_ADDRESS)
return false;
if (!domain_str_value)
{
stream.Printf("domain: nil - code: %" PRIu64, code);
return true;
}
InferiorSizedWord isw(domain_str_value, *process_sp);
ValueObjectSP domain_str_sp = ValueObject::CreateValueObjectFromData("domain_str", isw.GetAsData(process_sp->GetByteOrder()), valobj.GetExecutionContextRef(), process_sp->GetTarget().GetScratchClangASTContext()->GetBasicType(lldb::eBasicTypeVoid).GetPointerType());
if (!domain_str_sp)
return false;
StreamString domain_str_summary;
if (NSStringSummaryProvider(*domain_str_sp, domain_str_summary, options) && !domain_str_summary.Empty())
{
stream.Printf("domain: %s - code: %" PRIu64, domain_str_summary.GetData(), code);
return true;
}
else
{
stream.Printf("domain: nil - code: %" PRIu64, code);
return true;
}
}
class NSErrorSyntheticFrontEnd : public SyntheticChildrenFrontEnd
{
public:
NSErrorSyntheticFrontEnd (lldb::ValueObjectSP valobj_sp) :
SyntheticChildrenFrontEnd(*valobj_sp)
{}
~NSErrorSyntheticFrontEnd() override = default;
// no need to delete m_child_ptr - it's kept alive by the cluster manager on our behalf
size_t
CalculateNumChildren() override
{
if (m_child_ptr)
return 1;
if (m_child_sp)
return 1;
return 0;
}
lldb::ValueObjectSP
GetChildAtIndex(size_t idx) override
{
if (idx != 0)
return lldb::ValueObjectSP();
if (m_child_ptr)
return m_child_ptr->GetSP();
return m_child_sp;
}
bool
Update() override
{
m_child_ptr = nullptr;
m_child_sp.reset();
ProcessSP process_sp(m_backend.GetProcessSP());
if (!process_sp)
return false;
lldb::addr_t userinfo_location = DerefToNSErrorPointer(m_backend);
if (userinfo_location == LLDB_INVALID_ADDRESS)
return false;
size_t ptr_size = process_sp->GetAddressByteSize();
userinfo_location += 4 * ptr_size;
Error error;
lldb::addr_t userinfo = process_sp->ReadPointerFromMemory(userinfo_location, error);
if (userinfo == LLDB_INVALID_ADDRESS || error.Fail())
return false;
InferiorSizedWord isw(userinfo,*process_sp);
m_child_sp = ValueObject::CreateValueObjectFromData("_userInfo",
isw.GetAsData(process_sp->GetByteOrder()),
m_backend.GetExecutionContextRef(),
process_sp->GetTarget().GetScratchClangASTContext()->GetBasicType(lldb::eBasicTypeObjCID));
return false;
}
bool
MightHaveChildren() override
{
return true;
}
size_t
GetIndexOfChildWithName(const ConstString &name) override
{
static ConstString g___userInfo("_userInfo");
if (name == g___userInfo)
return 0;
return UINT32_MAX;
}
private:
// the child here can be "real" (i.e. an actual child of the root) or synthetized from raw memory
// if the former, I need to store a plain pointer to it - or else a loop of references will cause this entire hierarchy of values to leak
// if the latter, then I need to store a SharedPointer to it - so that it only goes away when everyone else in the cluster goes away
// oh joy!
ValueObject* m_child_ptr;
ValueObjectSP m_child_sp;
};
SyntheticChildrenFrontEnd*
lldb_private::formatters::NSErrorSyntheticFrontEndCreator (CXXSyntheticChildren*, lldb::ValueObjectSP valobj_sp)
{
lldb::ProcessSP process_sp (valobj_sp->GetProcessSP());
if (!process_sp)
return nullptr;
ObjCLanguageRuntime *runtime = (ObjCLanguageRuntime*)process_sp->GetLanguageRuntime(lldb::eLanguageTypeObjC);
if (!runtime)
return nullptr;
ObjCLanguageRuntime::ClassDescriptorSP descriptor(runtime->GetClassDescriptor(*valobj_sp.get()));
if (!descriptor.get() || !descriptor->IsValid())
return nullptr;
const char* class_name = descriptor->GetClassName().GetCString();
if (!class_name || !*class_name)
return nullptr;
if (!strcmp(class_name,"NSError"))
return (new NSErrorSyntheticFrontEnd(valobj_sp));
else if (!strcmp(class_name,"__NSCFError"))
return (new NSErrorSyntheticFrontEnd(valobj_sp));
return nullptr;
}