From 3170cb7891bd6980695f86349950a03baef958f9 Mon Sep 17 00:00:00 2001
From: short <>
Date: Sat, 5 Jul 2003 19:53:26 +0000
Subject: [PATCH] _abnormal_termination() is now "wrap"ed by %fs:[0] protection
 agains '-1'  - there is no toplevel exception handler registered by
 libcaptive

---
 src/libcaptive/ke/exports.captivesym |  4 ++--
 src/libcaptive/ps/signal.c           | 33 +++++++++++++++++++++++----------
 2 files changed, 25 insertions(+), 12 deletions(-)

diff --git a/src/libcaptive/ke/exports.captivesym b/src/libcaptive/ke/exports.captivesym
index d76fea2..b429ed7 100644
--- a/src/libcaptive/ke/exports.captivesym
+++ b/src/libcaptive/ke/exports.captivesym
@@ -334,8 +334,8 @@ ntoskrnl.exe	IoReleaseCancelSpinLock
 ntoskrnl.exe	_global_unwind2
 ntoskrnl.exe	RtlUnwind
 ntoskrnl.exe	_local_unwind2	pass
-# we can use iff "_local_unwind2 pass" as there is registered local handler to %fs:[0]:
-ntoskrnl.exe	_abnormal_termination	pass
+# we can pass iff "_local_unwind2 pass" as there is registered local handler to %fs:[0]:
+ntoskrnl.exe	_abnormal_termination	wrap
 ntoskrnl.exe	FsRtlIncrementCcFastReadNoWait
 ntoskrnl.exe	FsRtlResetLargeMcb	pass
 ntoskrnl.exe	RtlGetCompressionWorkSpaceSize	pass
diff --git a/src/libcaptive/ps/signal.c b/src/libcaptive/ps/signal.c
index c042f54..1e78c4c 100644
--- a/src/libcaptive/ps/signal.c
+++ b/src/libcaptive/ps/signal.c
@@ -34,27 +34,40 @@
 #include "captive/ldr_exports.h"	/* for struct captive_ModuleList_patchpoint */
 
 
-#if 0	/* Currently implemented for real by "pass" to native ntoskrnl. */
+int _abnormal_termination_orig(void);
+extern greg_t fs_KPCR_ExceptionList;
+
 /**
- * _abnormal_termination:
+ * _abnormal_termination_wrap:
+ *
+ * This call can be also accessed as AbnormalTermination() or _abnormal_termination().
+ * It is a captive wrapper around _abnormal_termination() function.
  *
- * This call can be also accessed as AbnormalTermination() or abnormal_termination().
+ * Returns whether some exception occured in the current #try block we are currently
+ * #finish -ing. Any functions called from current #finish block will be considered
+ * for returning zero back again. It is forbidden to call this function outside
+ * of #finish block, result of such call is undefined.
  *
- * Returns whether some exception occured (FIXME: in what scope?).
  * Exception handlers are registered from W32 binary in stack frames stored in "fs:[0x00000000]"
  * value which gets mapped by libcaptive/ps/signal.c to #fs_KPCR_ExceptionList
  * variable.
  *
- * libcaptive currently does not raise any exceptions therefore this call always returns value %0.
- * See RtlpDispatchException().
+ * If no exception handler was registered yet this function returns zero.
+ *
+ * See also RtlpDispatchException().
  *
- * Returns: non-zero if some exception is now registered and pending.
+ * Returns: non-zero if some exception is now being handled as pending.
  */
-int _abnormal_termination(void)
+int _abnormal_termination_wrap(void)
 {
-	return 0;
+	/* No handler registered yet? ntoskrnl _abnormal_termination() does not handle it
+	 * and I do not want to bother with registering toplevel handler.
+	 */
+	if (fs_KPCR_ExceptionList==(greg_t)-1)
+		return 0;
+
+	return _abnormal_termination_orig();
 }
-#endif
 
 
 #if 0
-- 
1.8.3.1