contrib/llvm/tools/lldb/source/Plugins/Language/ObjC/NSException.cpp

   1 //===-- NSException.cpp -----------------------------------------*- C++ -*-===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9
  10 #include "clang/AST/DeclCXX.h"
  11
  12 #include "Cocoa.h"
  13
  14 #include "lldb/Core/ValueObject.h"
  15 #include "lldb/Core/ValueObjectConstResult.h"
  16 #include "lldb/DataFormatters/FormattersHelpers.h"
  17 #include "lldb/Symbol/ClangASTContext.h"
  18 #include "lldb/Target/ObjCLanguageRuntime.h"
  19 #include "lldb/Target/ProcessStructReader.h"
  20 #include "lldb/Target/Target.h"
  21 #include "lldb/Utility/DataBufferHeap.h"
  22 #include "lldb/Utility/Endian.h"
  23 #include "lldb/Utility/Status.h"
  24 #include "lldb/Utility/Stream.h"
  25
  26 #include "Plugins/Language/ObjC/NSString.h"
  27
  28 using namespace lldb;
  29 using namespace lldb_private;
  30 using namespace lldb_private::formatters;
  31
  32 static bool ExtractFields(ValueObject &valobj, ValueObjectSP *name_sp,
  33                           ValueObjectSP *reason_sp, ValueObjectSP *userinfo_sp,
  34                           ValueObjectSP *reserved_sp) {
  35   ProcessSP process_sp(valobj.GetProcessSP());
  36   if (!process_sp)
  37     return false;
  38
  39   lldb::addr_t ptr = LLDB_INVALID_ADDRESS;
  40
  41   CompilerType valobj_type(valobj.GetCompilerType());
  42   Flags type_flags(valobj_type.GetTypeInfo());
  43   if (type_flags.AllClear(eTypeHasValue)) {
  44     if (valobj.IsBaseClass() && valobj.GetParent())
  45       ptr = valobj.GetParent()->GetValueAsUnsigned(LLDB_INVALID_ADDRESS);
  46   } else {
  47     ptr = valobj.GetValueAsUnsigned(LLDB_INVALID_ADDRESS);
  48   }
  49
  50   if (ptr == LLDB_INVALID_ADDRESS)
  51     return false;
  52   size_t ptr_size = process_sp->GetAddressByteSize();
  53
  54   Status error;
  55   auto name = process_sp->ReadPointerFromMemory(ptr + 1 * ptr_size, error);
  56   if (error.Fail() || name == LLDB_INVALID_ADDRESS)
  57     return false;
  58   auto reason = process_sp->ReadPointerFromMemory(ptr + 2 * ptr_size, error);
  59   if (error.Fail() || reason == LLDB_INVALID_ADDRESS)
  60     return false;
  61   auto userinfo = process_sp->ReadPointerFromMemory(ptr + 3 * ptr_size, error);
  62   if (error.Fail() || userinfo == LLDB_INVALID_ADDRESS)
  63     return false;
  64   auto reserved = process_sp->ReadPointerFromMemory(ptr + 4 * ptr_size, error);
  65   if (error.Fail() || reserved == LLDB_INVALID_ADDRESS)
  66     return false;
  67
  68   InferiorSizedWord name_isw(name, *process_sp);
  69   InferiorSizedWord reason_isw(reason, *process_sp);
  70   InferiorSizedWord userinfo_isw(userinfo, *process_sp);
  71   InferiorSizedWord reserved_isw(reserved, *process_sp);
  72
  73   CompilerType voidstar = process_sp->GetTarget()
  74                               .GetScratchClangASTContext()
  75                               ->GetBasicType(lldb::eBasicTypeVoid)
  76                               .GetPointerType();
  77
  78   if (name_sp)
  79     *name_sp = ValueObject::CreateValueObjectFromData(
  80         "name", name_isw.GetAsData(process_sp->GetByteOrder()),
  81         valobj.GetExecutionContextRef(), voidstar);
  82   if (reason_sp)
  83     *reason_sp = ValueObject::CreateValueObjectFromData(
  84         "reason", reason_isw.GetAsData(process_sp->GetByteOrder()),
  85         valobj.GetExecutionContextRef(), voidstar);
  86   if (userinfo_sp)
  87     *userinfo_sp = ValueObject::CreateValueObjectFromData(
  88         "userInfo", userinfo_isw.GetAsData(process_sp->GetByteOrder()),
  89         valobj.GetExecutionContextRef(), voidstar);
  90   if (reserved_sp)
  91     *reserved_sp = ValueObject::CreateValueObjectFromData(
  92         "reserved", reserved_isw.GetAsData(process_sp->GetByteOrder()),
  93         valobj.GetExecutionContextRef(), voidstar);
  94
  95   return true;
  96 }
  97
  98 bool lldb_private::formatters::NSException_SummaryProvider(
  99     ValueObject &valobj, Stream &stream, const TypeSummaryOptions &options) {
 100   lldb::ValueObjectSP name_sp;
 101   lldb::ValueObjectSP reason_sp;
 102   if (!ExtractFields(valobj, &name_sp, &reason_sp, nullptr, nullptr))
 103     return false;
 104
 105   if (!name_sp || !reason_sp)
 106     return false;
 107
 108   StreamString name_str_summary;
 109   StreamString reason_str_summary;
 110   if (NSStringSummaryProvider(*name_sp, name_str_summary, options) &&
 111       NSStringSummaryProvider(*reason_sp, reason_str_summary, options) &&
 112       !name_str_summary.Empty() && !reason_str_summary.Empty()) {
 113     stream.Printf("name: %s - reason: %s", name_str_summary.GetData(),
 114                   reason_str_summary.GetData());
 115     return true;
 116   } else
 117     return false;
 118 }
 119
 120 class NSExceptionSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
 121 public:
 122   NSExceptionSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp)
 123       : SyntheticChildrenFrontEnd(*valobj_sp) {}
 124
 125   ~NSExceptionSyntheticFrontEnd() override = default;
 126
 127   size_t CalculateNumChildren() override {
 128     return 4;
 129   }
 130
 131   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override {
 132     switch (idx) {
 133       case 0: return m_name_sp;
 134       case 1: return m_reason_sp;
 135       case 2: return m_userinfo_sp;
 136       case 3: return m_reserved_sp;
 137     }
 138     return lldb::ValueObjectSP();
 139   }
 140
 141   bool Update() override {
 142     m_name_sp.reset();
 143     m_reason_sp.reset();
 144     m_userinfo_sp.reset();
 145     m_reserved_sp.reset();
 146
 147     return ExtractFields(m_backend, &m_name_sp, &m_reason_sp, &m_userinfo_sp,
 148                          &m_reserved_sp);
 149   }
 150
 151   bool MightHaveChildren() override { return true; }
 152
 153   size_t GetIndexOfChildWithName(const ConstString &name) override {
 154     // NSException has 4 members:
 155     //   NSString *name;
 156     //   NSString *reason;
 157     //   NSDictionary *userInfo;
 158     //   id reserved;
 159     static ConstString g___name("name");
 160     static ConstString g___reason("reason");
 161     static ConstString g___userInfo("userInfo");
 162     static ConstString g___reserved("reserved");
 163     if (name == g___name) return 0;
 164     if (name == g___reason) return 1;
 165     if (name == g___userInfo) return 2;
 166     if (name == g___reserved) return 3;
 167     return UINT32_MAX;
 168   }
 169
 170 private:
 171   ValueObjectSP m_name_sp;
 172   ValueObjectSP m_reason_sp;
 173   ValueObjectSP m_userinfo_sp;
 174   ValueObjectSP m_reserved_sp;
 175 };
 176
 177 SyntheticChildrenFrontEnd *
 178 lldb_private::formatters::NSExceptionSyntheticFrontEndCreator(
 179     CXXSyntheticChildren *, lldb::ValueObjectSP valobj_sp) {
 180   lldb::ProcessSP process_sp(valobj_sp->GetProcessSP());
 181   if (!process_sp)
 182     return nullptr;
 183   ObjCLanguageRuntime *runtime =
 184       (ObjCLanguageRuntime *)process_sp->GetLanguageRuntime(
 185           lldb::eLanguageTypeObjC);
 186   if (!runtime)
 187     return nullptr;
 188
 189   ObjCLanguageRuntime::ClassDescriptorSP descriptor(
 190       runtime->GetClassDescriptor(*valobj_sp.get()));
 191
 192   if (!descriptor.get() || !descriptor->IsValid())
 193     return nullptr;
 194
 195   const char *class_name = descriptor->GetClassName().GetCString();
 196
 197   if (!class_name || !*class_name)
 198     return nullptr;
 199
 200   if (!strcmp(class_name, "NSException"))
 201     return (new NSExceptionSyntheticFrontEnd(valobj_sp));
 202   else if (!strcmp(class_name, "NSCFException"))
 203     return (new NSExceptionSyntheticFrontEnd(valobj_sp));
 204   else if (!strcmp(class_name, "__NSCFException"))
 205     return (new NSExceptionSyntheticFrontEnd(valobj_sp));
 206
 207   return nullptr;
 208 }