Fixed error handling when the utility functions

that check pointer validity fail to parse.  Now
lldb does not crash in that case.  Also added
support for checking Objective-C class validity
in the Version 1 runtime as well as Version 2
runtimes with varying levels of available debug
support.

llvm-svn: 118271

6 files changed, 89 insertions, 37 deletions

diff --git a/lldb/source/Expression/ClangUserExpression.cpp b/lldb/source/Expression/ClangUserExpression.cpp
index 5181c98c9aa..e75c323912c 100644
--- a/lldb/source/Expression/ClangUserExpression.cpp
+++ b/lldb/source/Expression/ClangUserExpression.cpp
@@ -449,8 +449,16 @@ ClangUserExpression::Evaluate (ExecutionContext &exe_ctx,
         StreamString install_errors;
         
         if (!dynamic_checkers->Install(install_errors, exe_ctx))
+        {
+            if (install_errors.GetString().empty())
+                error.SetErrorString ("couldn't install checkers, unknown error");
+            else
+                error.SetErrorString (install_errors.GetString().c_str());
+            
+            result_valobj_sp.reset (new ValueObjectConstResult (error));
             return result_valobj_sp;
-        
+        }
+            
         exe_ctx.process->SetDynamicCheckers(dynamic_checkers);
     }
     
diff --git a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.cpp b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.cpp
index a7cdd1a4275..0556f10c4fc 100644
--- a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.cpp
+++ b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.cpp
@@ -231,7 +231,7 @@ AppleObjCRuntime::GetStepThroughTrampolinePlan (Thread &thread, bool stop_others
 // Static Functions
 //------------------------------------------------------------------
 enum AppleObjCRuntime::RuntimeVersions
-AppleObjCRuntime::GetObjCVersion (Process *process)
+AppleObjCRuntime::GetObjCVersion (Process *process, ModuleSP &objc_module_sp)
 {
     ModuleList &images = process->GetTarget().GetImages();
     size_t num_images = images.GetSize();
@@ -240,6 +240,7 @@ AppleObjCRuntime::GetObjCVersion (Process *process)
         ModuleSP module_sp = images.GetModuleAtIndex(i);
         if (AppleIsModuleObjCLibrary (module_sp))
         {
+            objc_module_sp = module_sp;
             ObjectFile *ofile = module_sp->GetObjectFile();
             if (!ofile)
                 return eObjC_VersionUnknown;
diff --git a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.h b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.h
index 45884c0ea90..aab0f348b5f 100644
--- a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.h
+++ b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.h
@@ -74,7 +74,7 @@ protected:
     AppleIsModuleObjCLibrary (const lldb::ModuleSP &module_sp);
 
     static enum AppleObjCRuntime::RuntimeVersions
-    GetObjCVersion (Process *process);
+    GetObjCVersion (Process *process, ModuleSP &objc_module_sp);
 
     //------------------------------------------------------------------
     // PluginInterface protocol
diff --git a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV1.cpp b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV1.cpp
index 87136937f45..e786da9e145 100644
--- a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV1.cpp
+++ b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV1.cpp
@@ -172,7 +172,9 @@ AppleObjCRuntimeV1::CreateInstance (Process *process, lldb::LanguageType languag
     // sure we aren't using the V1 runtime.
     if (language == eLanguageTypeObjC)
     {
-        if (AppleObjCRuntime::GetObjCVersion (process) == AppleObjCRuntime::eObjC_V1)
+        ModuleSP objc_module_sp;
+        
+        if (AppleObjCRuntime::GetObjCVersion (process, objc_module_sp) == AppleObjCRuntime::eObjC_V1)
             return new AppleObjCRuntimeV1 (process);
         else
             return NULL;
@@ -231,22 +233,36 @@ AppleObjCRuntimeV1::SetExceptionBreakpoints ()
     }
 }
 
+struct BufStruct {
+    char contents[2048];
+};
+
 ClangUtilityFunction *
 AppleObjCRuntimeV1::CreateObjectChecker(const char *name)
 {
-//    char buf[256];
-//    
-//    assert(snprintf(&buf[0], sizeof(buf), 
-//                    "extern \"C\" int gdb_object_getClass(void *);"
-//                    "extern \"C\" void "
-//                    "%s(void *$__lldb_arg_obj)"
-//                    "{"
-//                    "    void **isa_ptr = (void **)$__lldb_arg_obj;"
-//                    "    if (!isa_ptr || !gdb_class_getClass(*isa_ptr))"
-//                    "        abort();"
-//                    "}", 
-//                    name) < sizeof(buf));
-//
-//    return new ClangUtilityFunction(buf, name);
-    return NULL;
+    std::auto_ptr<BufStruct> buf(new BufStruct);
+    
+    assert(snprintf(&buf->contents[0], sizeof(buf->contents),
+                    "struct __objc_class                                                    \n"
+                    "{                                                                      \n"
+                    "   struct __objc_class *isa;                                           \n"
+                    "   struct __objc_class *super_class;                                   \n"
+                    "   const char *name;                                                   \n"
+                    "   // rest of struct elided because unused                             \n"
+                    "};                                                                     \n"
+                    "                                                                       \n"
+                    "struct __objc_object                                                   \n"
+                    "{                                                                      \n"
+                    "   struct __objc_class *isa;                                           \n"
+                    "};                                                                     \n"
+                    "                                                                       \n"
+                    "extern \"C\" void                                                      \n"
+                    "%s(void *$__lldb_arg_obj)                                              \n"
+                    "{                                                                      \n"
+                    "   struct __objc_object *obj = (struct __objc_object*)$__lldb_arg_obj; \n"
+                    "   strlen(obj->isa->name);                                             \n"
+                    "}                                                                      \n",
+                    name) < sizeof(buf->contents));
+
+    return new ClangUtilityFunction(buf->contents, name);
 }
diff --git a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.cpp b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.cpp
index c5aa42a6964..17280090bff 100644
--- a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.cpp
+++ b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.cpp
@@ -40,6 +40,12 @@ static const char *pluginName = "AppleObjCRuntimeV2";
 static const char *pluginDesc = "Apple Objective C Language Runtime - Version 2";
 static const char *pluginShort = "language.apple.objc.v2";
 
+AppleObjCRuntimeV2::AppleObjCRuntimeV2 (Process *process, ModuleSP &objc_module_sp) : 
+    lldb_private::AppleObjCRuntime (process)
+{
+    m_has_object_getClass = (objc_module_sp->FindFirstSymbolWithNameAndType(ConstString("gdb_object_getClass")) != NULL);
+}
+
 bool
 AppleObjCRuntimeV2::GetObjectDescription (Stream &str, ValueObject &object, ExecutionContextScope *exe_scope)
 {
@@ -172,8 +178,10 @@ AppleObjCRuntimeV2::CreateInstance (Process *process, lldb::LanguageType languag
     // sure we aren't using the V1 runtime.
     if (language == eLanguageTypeObjC)
     {
-        if (AppleObjCRuntime::GetObjCVersion (process) == AppleObjCRuntime::eObjC_V2)
-            return new AppleObjCRuntimeV2 (process);
+        ModuleSP objc_module_sp;
+        
+        if (AppleObjCRuntime::GetObjCVersion (process, objc_module_sp) == AppleObjCRuntime::eObjC_V2)
+            return new AppleObjCRuntimeV2 (process, objc_module_sp);
         else
             return NULL;
     }
@@ -231,21 +239,40 @@ AppleObjCRuntimeV2::SetExceptionBreakpoints ()
     }
 }
 
+struct BufStruct {
+    char contents[1024];
+};
+
 ClangUtilityFunction *
 AppleObjCRuntimeV2::CreateObjectChecker(const char *name)
 {
-    char buf[256];
+    std::auto_ptr<BufStruct> buf(new BufStruct);
+    
+    if (m_has_object_getClass)
+    {
+        assert(snprintf(&buf->contents[0], sizeof(buf->contents),
+                        "extern \"C\" int gdb_object_getClass(void *);      \n"
+                        "extern \"C\" void                                  \n"
+                        "%s(void *$__lldb_arg_obj)                          \n"
+                        "{                                                  \n"
+                        "   if (!gdb_object_getClass($__lldb_arg_obj))      \n"
+                        "       abort();                                    \n"
+                        "}                                                  \n",
+                        name) < sizeof(buf->contents));
+    }
+    else
+    {
+        assert(snprintf(&buf->contents[0], sizeof(buf->contents), 
+                        "extern \"C\" int gdb_class_getClass(void *);       \n"
+                        "extern \"C\" void                                  \n"
+                        "%s(void *$__lldb_arg_obj)                          \n"
+                        "{                                                  \n"
+                        "    void **isa_ptr = (void **)$__lldb_arg_obj;     \n"
+                        "    if (!isa_ptr || !gdb_class_getClass(*isa_ptr)) \n"
+                        "        abort();                                   \n"
+                        "}                                                  \n", 
+                        name) < sizeof(buf->contents));
+    }
     
-    assert(snprintf(&buf[0], sizeof(buf), 
-                    "extern \"C\" int gdb_object_getClass(void *);"
-                    "extern \"C\" void "
-                    "%s(void *$__lldb_arg_obj)"
-                    "{"
-                    "    void **isa_ptr = (void **)$__lldb_arg_obj;"
-                    "    if (!isa_ptr || !gdb_class_getClass(*isa_ptr))"
-                    "        abort();"
-                    "}", 
-                    name) < sizeof(buf));
-
-    return new ClangUtilityFunction(buf, name);
+    return new ClangUtilityFunction(buf->contents, name);
 }
diff --git a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.h b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.h
index d6ab630ee52..4bba44d8075 100644
--- a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.h
+++ b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.h
@@ -74,9 +74,9 @@ public:
 protected:
     
 private:
-    AppleObjCRuntimeV2(Process *process) : 
-        lldb_private::AppleObjCRuntime (process)
-     { } // Call CreateInstance instead.
+    AppleObjCRuntimeV2(Process *process, ModuleSP &objc_module_sp);
+    
+    bool m_has_object_getClass;
 };
     
 } // namespace lldb_private