From 87e5ec8869648028140145acc58be4cf5b07d5f2 Mon Sep 17 00:00:00 2001
From: Daniel Lehman <dlehman@esri.com>
Date: Fri, 19 May 2017 11:03:28 -0700
Subject: [PATCH 2/7] msvcrt: Clean up registered C++ object in handler.

this ties into the following commit in support of nested c++ exceptions

this moves the cleaning up of objects registered in
call_catch_block from cxx_frame_handler to a custom handler

before this commit:
...
    call_consolidate
    call_catch_block <- register c++ obj
    catch$0          <- cxx_frame_handler, destroy registered objs to this frame
...

after this commit:
...
    call_consolidate
    call_catch_block <- register c++ obj on entry, cxx_catch_cleanup destroys it on unwind
    catch$0
...

Signed-off-by: Daniel Lehman <dlehman@esri.com>
---
 dlls/msvcrt/except_x86_64.c | 64 +++++++++++++++++++++++++++++----------------
 1 file changed, 41 insertions(+), 23 deletions(-)

diff --git a/dlls/msvcrt/except_x86_64.c b/dlls/msvcrt/except_x86_64.c
index 6b0557a..ec18746 100644
--- a/dlls/msvcrt/except_x86_64.c
+++ b/dlls/msvcrt/except_x86_64.c
@@ -320,33 +320,67 @@ static void cxx_local_unwind(ULONG64 frame, DISPATCHER_CONTEXT *dispatch,
     unwind_help[0] = last_level;
 }
 
-static inline void* WINAPI call_catch_block(EXCEPTION_RECORD *rec)
+static void* WINAPI call_catch_block(EXCEPTION_RECORD *rec);
+
+static inline BOOL cxx_is_consolidate(const EXCEPTION_RECORD *rec)
+{
+    return rec->ExceptionCode==STATUS_UNWIND_CONSOLIDATE && rec->NumberParameters==6 &&
+           rec->ExceptionInformation[0]==(ULONG_PTR)call_catch_block;
+}
+
+static DWORD cxx_catch_cleanup(EXCEPTION_RECORD *rec, EXCEPTION_REGISTRATION_RECORD *frame,
+                               CONTEXT *context, EXCEPTION_REGISTRATION_RECORD **pdispatcher)
+{
+    if (rec->ExceptionFlags & (EH_UNWINDING | EH_EXIT_UNWIND))
+    {
+        thread_data_t *data = msvcrt_get_thread_data();
+        frame_info *cur;
+
+        if (cxx_is_consolidate(rec))
+        {
+            rec = (void*)rec->ExceptionInformation[4];
+
+            for (cur = data->frame_info_head; cur; cur = cur->next)
+            {
+                if ((ULONG64)cur <= (ULONG64)frame)
+                {
+                    __CxxUnregisterExceptionObject((cxx_frame_info*)cur,
+                            rec->ExceptionCode == CXX_EXCEPTION &&
+                            data->exc_record->ExceptionCode == CXX_EXCEPTION &&
+                            rec->ExceptionInformation[1] == data->exc_record->ExceptionInformation[1]);
+                }
+            }
+        }
+    }
+    return ExceptionContinueSearch;
+}
+
+static void* WINAPI call_catch_block(EXCEPTION_RECORD *rec)
 {
     ULONG64 frame = rec->ExceptionInformation[1];
     const cxx_function_descr *descr = (void*)rec->ExceptionInformation[2];
     EXCEPTION_RECORD *prev_rec = (void*)rec->ExceptionInformation[4];
     void* (__cdecl *handler)(ULONG64 unk, ULONG64 rbp) = (void*)rec->ExceptionInformation[5];
     int *unwind_help = rva_to_ptr(descr->unwind_help, frame);
+    EXCEPTION_REGISTRATION_RECORD catch_frame;
     cxx_frame_info frame_info;
     void *ret_addr;
 
     TRACE("calling handler %p\n", handler);
 
     /* FIXME:  native does local_unwind here in case of exception rethrow */
+    catch_frame.Handler = cxx_catch_cleanup;
+    __wine_push_frame(&catch_frame);
     __CxxRegisterExceptionObject(&prev_rec, &frame_info);
     ret_addr = handler(0, frame);
     __CxxUnregisterExceptionObject(&frame_info, FALSE);
+    __wine_pop_frame(&catch_frame);
+
     unwind_help[0] = -2;
     unwind_help[1] = -1;
     return ret_addr;
 }
 
-static inline BOOL cxx_is_consolidate(const EXCEPTION_RECORD *rec)
-{
-    return rec->ExceptionCode==STATUS_UNWIND_CONSOLIDATE && rec->NumberParameters==6 &&
-           rec->ExceptionInformation[0]==(ULONG_PTR)call_catch_block;
-}
-
 static inline void find_catch_block(EXCEPTION_RECORD *rec, ULONG64 frame,
                                     DISPATCHER_CONTEXT *dispatch,
                                     const cxx_function_descr *descr,
@@ -528,10 +562,6 @@ static DWORD cxx_frame_handler(EXCEPTION_RECORD *rec, ULONG64 frame,
     {
         if (cxx_is_consolidate(rec))
         {
-            EXCEPTION_RECORD *new_rec = (void*)rec->ExceptionInformation[4];
-            thread_data_t *data = msvcrt_get_thread_data();
-            frame_info *cur;
-
             if (rec->ExceptionFlags & EH_TARGET_UNWIND)
             {
                 const cxx_function_descr *orig_descr = (void*)rec->ExceptionInformation[2];
@@ -542,18 +572,6 @@ static DWORD cxx_frame_handler(EXCEPTION_RECORD *rec, ULONG64 frame,
             }
             else if(frame == orig_frame)
                 cxx_local_unwind(frame, dispatch, descr, -1);
-
-            /* FIXME: we should only unregister frames registered by call_catch_block here */
-            for (cur = data->frame_info_head; cur; cur = cur->next)
-            {
-                if ((ULONG64)cur <= frame)
-                {
-                    __CxxUnregisterExceptionObject((cxx_frame_info*)cur,
-                            new_rec->ExceptionCode == CXX_EXCEPTION &&
-                            data->exc_record->ExceptionCode == CXX_EXCEPTION &&
-                            new_rec->ExceptionInformation[1] == data->exc_record->ExceptionInformation[1]);
-                }
-            }
             return ExceptionContinueSearch;
         }
 
-- 
1.9.5