[lldb] Extract more fields from NSException values
authorKuba Mracek <mracek@apple.com>
Mon, 12 Nov 2018 19:12:31 +0000 (19:12 +0000)
committerKuba Mracek <mracek@apple.com>
Mon, 12 Nov 2018 19:12:31 +0000 (19:12 +0000)
This patch teaches LLDB about more fields on NSException Obj-C objects, specifically we can now retrieve the "name" and "reason" of an NSException. The goal is to eventually be able to have SB API that can provide details about the currently thrown/caught/processed exception.

Differential Revision: https://reviews.llvm.org/D43884

llvm-svn: 346695

lldb/packages/Python/lldbsuite/test/lang/objc/exceptions/Makefile [new file with mode: 0644]
lldb/packages/Python/lldbsuite/test/lang/objc/exceptions/TestObjCExceptions.py [new file with mode: 0644]
lldb/packages/Python/lldbsuite/test/lang/objc/exceptions/main.m [new file with mode: 0644]
lldb/source/Plugins/Language/ObjC/NSException.cpp

diff --git a/lldb/packages/Python/lldbsuite/test/lang/objc/exceptions/Makefile b/lldb/packages/Python/lldbsuite/test/lang/objc/exceptions/Makefile
new file mode 100644 (file)
index 0000000..9f7fb1c
--- /dev/null
@@ -0,0 +1,9 @@
+LEVEL = ../../../make
+
+OBJC_SOURCES := main.m
+
+CFLAGS_EXTRAS += -w
+
+include $(LEVEL)/Makefile.rules
+
+LDFLAGS += -framework Foundation
diff --git a/lldb/packages/Python/lldbsuite/test/lang/objc/exceptions/TestObjCExceptions.py b/lldb/packages/Python/lldbsuite/test/lang/objc/exceptions/TestObjCExceptions.py
new file mode 100644 (file)
index 0000000..423776c
--- /dev/null
@@ -0,0 +1,90 @@
+# encoding: utf-8
+"""
+Test lldb Obj-C exception support.
+"""
+
+from __future__ import print_function
+
+
+import lldb
+from lldbsuite.test.decorators import *
+from lldbsuite.test.lldbtest import *
+from lldbsuite.test import lldbutil
+
+
+class ObjCExceptionsTestCase(TestBase):
+
+    mydir = TestBase.compute_mydir(__file__)
+
+    @skipUnlessDarwin
+    def test_objc_exceptions_1(self):
+        self.build()
+
+        target = self.dbg.CreateTarget(self.getBuildArtifact("a.out"))
+        self.assertTrue(target, VALID_TARGET)
+
+        lldbutil.run_to_source_breakpoint(self, "// Set break point at this line.", lldb.SBFileSpec("main.m"))
+
+        self.expect("thread list", STOPPED_DUE_TO_BREAKPOINT,
+                    substrs=['stopped', 'stop reason = breakpoint'])
+
+        thread = self.dbg.GetSelectedTarget().GetProcess().GetSelectedThread()
+        frame = thread.GetSelectedFrame()
+
+        self.expect(
+            'frame variable e1',
+            substrs=[
+                '(NSException *) e1 = ',
+                'name: @"ExceptionName" - reason: @"SomeReason"'
+            ])
+
+        self.expect(
+            'frame variable --dynamic-type no-run-target *e1',
+            substrs=[
+                '(NSException) *e1 = ',
+                'name = ', '@"ExceptionName"',
+                'reason = ', '@"SomeReason"',
+                'userInfo = ', '1 key/value pair',
+                'reserved = ', 'nil',
+            ])
+
+        e1 = frame.FindVariable("e1")
+        self.assertTrue(e1)
+        self.assertEqual(e1.type.name, "NSException *")
+        self.assertEqual(e1.GetSummary(), 'name: @"ExceptionName" - reason: @"SomeReason"')
+        self.assertEqual(e1.GetChildMemberWithName("name").description, "ExceptionName")
+        self.assertEqual(e1.GetChildMemberWithName("reason").description, "SomeReason")
+        userInfo = e1.GetChildMemberWithName("userInfo").dynamic
+        self.assertEqual(userInfo.summary, "1 key/value pair")
+        self.assertEqual(userInfo.GetChildAtIndex(0).GetChildAtIndex(0).description, "some_key")
+        self.assertEqual(userInfo.GetChildAtIndex(0).GetChildAtIndex(1).description, "some_value")
+        self.assertEqual(e1.GetChildMemberWithName("reserved").description, "<nil>")
+
+        self.expect(
+            'frame variable e2',
+            substrs=[
+                '(NSException *) e2 = ',
+                'name: @"ThrownException" - reason: @"SomeReason"'
+            ])
+
+        self.expect(
+            'frame variable --dynamic-type no-run-target *e2',
+            substrs=[
+                '(NSException) *e2 = ',
+                'name = ', '@"ThrownException"',
+                'reason = ', '@"SomeReason"',
+                'userInfo = ', '1 key/value pair',
+                'reserved = ',
+            ])
+
+        e2 = frame.FindVariable("e2")
+        self.assertTrue(e2)
+        self.assertEqual(e2.type.name, "NSException *")
+        self.assertEqual(e2.GetSummary(), 'name: @"ThrownException" - reason: @"SomeReason"')
+        self.assertEqual(e2.GetChildMemberWithName("name").description, "ThrownException")
+        self.assertEqual(e2.GetChildMemberWithName("reason").description, "SomeReason")
+        userInfo = e2.GetChildMemberWithName("userInfo").dynamic
+        self.assertEqual(userInfo.summary, "1 key/value pair")
+        self.assertEqual(userInfo.GetChildAtIndex(0).GetChildAtIndex(0).description, "some_key")
+        self.assertEqual(userInfo.GetChildAtIndex(0).GetChildAtIndex(1).description, "some_value")
+        self.assertGreater(e2.GetChildMemberWithName("reserved").dynamic.num_children, 0)
diff --git a/lldb/packages/Python/lldbsuite/test/lang/objc/exceptions/main.m b/lldb/packages/Python/lldbsuite/test/lang/objc/exceptions/main.m
new file mode 100644 (file)
index 0000000..93ad726
--- /dev/null
@@ -0,0 +1,36 @@
+//===-- main.m ------------------------------------------------*- ObjC -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#import <Foundation/Foundation.h>
+
+void foo()
+{
+    NSDictionary *info = [NSDictionary dictionaryWithObjectsAndKeys:@"some_value", @"some_key", nil];
+    @throw [[NSException alloc] initWithName:@"ThrownException" reason:@"SomeReason" userInfo:info];
+}
+
+int main (int argc, const char * argv[])
+{
+    NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
+
+    NSDictionary *info = [NSDictionary dictionaryWithObjectsAndKeys:@"some_value", @"some_key", nil];
+    NSException *e1 = [[NSException alloc] initWithName:@"ExceptionName" reason:@"SomeReason" userInfo:info];
+    NSException *e2;
+
+    @try {
+        foo();
+    } @catch(NSException *e) {
+        e2 = e;
+    }
+
+    NSLog(@"1"); // Set break point at this line.
+    [pool drain];
+    return 0;
+}
+
index 66be60ffcb9dd2f93d7ac1dc1437c0d25708f71e..bb0bcb9468809d039d43aea2dbc7b1d16e17b992 100644 (file)
@@ -30,8 +30,8 @@ using namespace lldb_private;
 using namespace lldb_private::formatters;
 
 static bool ExtractFields(ValueObject &valobj, ValueObjectSP *name_sp,
-                          ValueObjectSP *reason_sp,
-                          ValueObjectSP *userinfo_sp) {
+                          ValueObjectSP *reason_sp, ValueObjectSP *userinfo_sp,
+                          ValueObjectSP *reserved_sp) {
   ProcessSP process_sp(valobj.GetProcessSP());
   if (!process_sp)
     return false;
@@ -61,10 +61,14 @@ static bool ExtractFields(ValueObject &valobj, ValueObjectSP *name_sp,
   auto userinfo = process_sp->ReadPointerFromMemory(ptr + 3 * ptr_size, error);
   if (error.Fail() || userinfo == LLDB_INVALID_ADDRESS)
     return false;
+  auto reserved = process_sp->ReadPointerFromMemory(ptr + 4 * ptr_size, error);
+  if (error.Fail() || reserved == LLDB_INVALID_ADDRESS)
+    return false;
 
   InferiorSizedWord name_isw(name, *process_sp);
   InferiorSizedWord reason_isw(reason, *process_sp);
   InferiorSizedWord userinfo_isw(userinfo, *process_sp);
+  InferiorSizedWord reserved_isw(reserved, *process_sp);
 
   CompilerType voidstar = process_sp->GetTarget()
                               .GetScratchClangASTContext()
@@ -83,6 +87,10 @@ static bool ExtractFields(ValueObject &valobj, ValueObjectSP *name_sp,
     *userinfo_sp = ValueObject::CreateValueObjectFromData(
         "userInfo", userinfo_isw.GetAsData(process_sp->GetByteOrder()),
         valobj.GetExecutionContextRef(), voidstar);
+  if (reserved_sp)
+    *reserved_sp = ValueObject::CreateValueObjectFromData(
+        "reserved", reserved_isw.GetAsData(process_sp->GetByteOrder()),
+        valobj.GetExecutionContextRef(), voidstar);
 
   return true;
 }
@@ -91,7 +99,7 @@ bool lldb_private::formatters::NSException_SummaryProvider(
     ValueObject &valobj, Stream &stream, const TypeSummaryOptions &options) {
   lldb::ValueObjectSP name_sp;
   lldb::ValueObjectSP reason_sp;
-  if (!ExtractFields(valobj, &name_sp, &reason_sp, nullptr))
+  if (!ExtractFields(valobj, &name_sp, &reason_sp, nullptr, nullptr))
     return false;
 
   if (!name_sp || !reason_sp)
@@ -117,19 +125,27 @@ public:
   ~NSExceptionSyntheticFrontEnd() override = default;
 
   size_t CalculateNumChildren() override {
-    return 1;
+    return 4;
   }
 
   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override {
     switch (idx) {
-      case 0: return m_userinfo_sp;
+      case 0: return m_name_sp;
+      case 1: return m_reason_sp;
+      case 2: return m_userinfo_sp;
+      case 3: return m_reserved_sp;
     }
     return lldb::ValueObjectSP();
   }
 
   bool Update() override {
+    m_name_sp.reset();
+    m_reason_sp.reset();
     m_userinfo_sp.reset();
-    if (!ExtractFields(m_backend, nullptr, nullptr, &m_userinfo_sp)) {
+    m_reserved_sp.reset();
+
+    if (!ExtractFields(m_backend, &m_name_sp, &m_reason_sp, &m_userinfo_sp,
+                       &m_reserved_sp)) {
       return false;
     }
     return true;
@@ -138,14 +154,27 @@ public:
   bool MightHaveChildren() override { return true; }
 
   size_t GetIndexOfChildWithName(const ConstString &name) override {
+    // NSException has 4 members:
+    //   NSString *name;
+    //   NSString *reason;
+    //   NSDictionary *userInfo;
+    //   id reserved;
+    static ConstString g___name("name");
+    static ConstString g___reason("reason");
     static ConstString g___userInfo("userInfo");
-    if (name == g___userInfo)
-      return 0;
+    static ConstString g___reserved("reserved");
+    if (name == g___name) return 0;
+    if (name == g___reason) return 1;
+    if (name == g___userInfo) return 2;
+    if (name == g___reserved) return 3;
     return UINT32_MAX;
   }
 
 private:
+  ValueObjectSP m_name_sp;
+  ValueObjectSP m_reason_sp;
   ValueObjectSP m_userinfo_sp;
+  ValueObjectSP m_reserved_sp;
 };
 
 SyntheticChildrenFrontEnd *