[PATCH 1/1] ntdll: Pass exception code to exception handlers in __C_specific_handler.

[Jacek Caban]

From: Jacek Caban

Fixes _exception_code() inside exception handlers.
---
 dlls/ntdll/tests/exception.c | 56 ++++++++++++++++++++++++++++++++++++
 dlls/ntdll/unwind.c          |  9 ++++--
 2 files changed, 62 insertions(+), 3 deletions(-)

diff --git a/dlls/ntdll/tests/exception.c b/dlls/ntdll/tests/exception.c
index f88d9714d13..550c99a06b8 100644
--- a/dlls/ntdll/tests/exception.c
+++ b/dlls/ntdll/tests/exception.c
@@ -2639,8 +2639,42 @@ static void WINAPI termination_handler(ULONG flags, ULONG64 frame)
     ok(frame == 0x1234, "frame = %p\n", (void*)frame);
 }

+struct exception_code_context
+{
+    EXCEPTION_RECORD *rec;
+    CONTEXT *context;
+    DISPATCHER_CONTEXT *dispatch;
+};
+
+static void invoke_c_handler(struct exception_code_context *ctx, ULONG_PTR frame)
+{
+    p__C_specific_handler(ctx->rec, frame, ctx->context, ctx->dispatch);
+    ok(0, "__C_specific_handler returned\n");
+}
+
+static void check_exception_code(ULONG_PTR code)
+{
+    ok(code == 0x123, "code = %llx\n", code);
+}
+
+static char call_invoke_c_handler_code[] = {
+    0x48,0x83,0xec,0x28,         /* 0:  subq     $0x28, %rsp*/
+    0x48,0x89,0xe2,              /* 4:  movq     %rsp, %rdx */
+    0x48,0xb8,0,0,0,0,0,0,0,0,   /* 7:  movabsq  $invoke_c_handler, %rax */
+    0xff,0xd0,                   /* 17: callq    *%rax */
+    0xcc,                        /* 19: int3 */
+    /* exception handler: */
+    0x48,0x89,0xc1,              /* 20: movq     %rax, %rcx */
+    0x48,0xb8,0,0,0,0,0,0,0,0,   /* 23: movabsq  $check_exception_code, %rax */
+    0xff,0xd0,                   /* 33: callq    *%rax */
+    0x48,0x83,0xc4,0x28,         /* 35: addq     $0x28, %rsp */
+    0xc3                         /* 39: retq */
+};
+
 static void test___C_specific_handler(void)
 {
+    void (*test_exception_code)(void *ctx) = code_mem;
+    struct exception_code_context ctx;
     DISPATCHER_CONTEXT dispatch;
     EXCEPTION_RECORD rec;
     CONTEXT context;
@@ -2681,6 +2715,28 @@ static void test___C_specific_handler(void)
     ok(termination_handler_called == 1, "termination_handler_called = %d\n",
             termination_handler_called);
     ok(dispatch.ScopeIndex == 1, "dispatch.ScopeIndex = %ld\n", dispatch.ScopeIndex);
+
+    *(void **)&call_invoke_c_handler_code[9] = invoke_c_handler;
+    *(void **)&call_invoke_c_handler_code[25] = check_exception_code;
+    memcpy(code_mem, call_invoke_c_handler_code, sizeof(call_invoke_c_handler_code));
+    memset(&rec, 0, sizeof(rec));
+    memset(&dispatch, 0, sizeof(dispatch));
+    memset(&context, 0, sizeof(context));
+    rec.ExceptionCode = 0x123;
+    dispatch.ImageBase = (ULONG_PTR)code_mem - 0x1000;
+    dispatch.ControlPc = (ULONG_PTR)code_mem + 7;
+    dispatch.HandlerData = &scope_table;
+    dispatch.ContextRecord = &context;
+    scope_table.Count = 1;
+    scope_table.ScopeRecord[0].BeginAddress = 0x1000;
+    scope_table.ScopeRecord[0].EndAddress = 0x1013;
+    scope_table.ScopeRecord[0].HandlerAddress = EXCEPTION_EXECUTE_HANDLER;
+    scope_table.ScopeRecord[0].JumpTarget = 0x1014;
+
+    ctx.rec = &rec;
+    ctx.context = &context;
+    ctx.dispatch = &dispatch;
+    test_exception_code(&ctx);
 }

/* This is heavily based on the i386 exception tests. */
diff --git a/dlls/ntdll/unwind.c b/dlls/ntdll/unwind.c
index c11bd9ddb9c..cd898086862 100644
--- a/dlls/ntdll/unwind.c
+++ b/dlls/ntdll/unwind.c
@@ -902,7 +902,8 @@ EXCEPTION_DISPOSITION WINAPI __C_specific_handler( EXCEPTION_RECORD *rec, void *
             }
             TRACE( "unwinding to target %Ix\n", base + table->ScopeRecord[i].JumpTarget );
             RtlUnwindEx( frame, (char *)base + table->ScopeRecord[i].JumpTarget,
-                         rec, 0, (CONTEXT *)dispatch->ContextRecord, dispatch->HistoryTable );
+                         rec, ULongToPtr(rec->ExceptionCode), (CONTEXT *)dispatch->ContextRecord,
+                         dispatch->HistoryTable );
         }
     }
     return ExceptionContinueSearch;
@@ -1593,7 +1594,8 @@ EXCEPTION_DISPOSITION WINAPI __C_specific_handler( EXCEPTION_RECORD *rec, void *
             }
             TRACE( "unwinding to target %lx\n", base + table->ScopeRecord[i].JumpTarget );
             RtlUnwindEx( frame, (char *)base + table->ScopeRecord[i].JumpTarget,
-                         rec, 0, dispatch->ContextRecord, dispatch->HistoryTable );
+                         rec, ULongToPtr(rec->ExceptionCode), dispatch->ContextRecord,
+                         dispatch->HistoryTable );
         }
     }
     return ExceptionContinueSearch;
@@ -2261,7 +2263,8 @@ EXCEPTION_DISPOSITION WINAPI __C_specific_handler( EXCEPTION_RECORD *rec, void *
             }
             TRACE( "unwinding to target %Ix\n", base + table->ScopeRecord[i].JumpTarget );
             RtlUnwindEx( frame, (char *)base + table->ScopeRecord[i].JumpTarget,
-                         rec, 0, dispatch->ContextRecord, dispatch->HistoryTable );
+                         rec, ULongToPtr(rec->ExceptionCode), dispatch->ContextRecord,
+                         dispatch->HistoryTable );
         }
     }
     return ExceptionContinueSearch;