From 96880dc3e7fb9a87aa6c18c0e08595af70103d30 Mon Sep 17 00:00:00 2001
From: Paolo Molaro <lupus@oddwiz.org>
Date: Tue, 12 Oct 2010 17:08:42 +0200
Subject: [PATCH] Fixed the console sigint deadlock, by queuing execution in
 the finalizer thread.

* console-io.h, console-null.c, console-unix.c, console-win32.c,
gc.c: instead of executing tons of managed code in signal context,
we wake up the finalizer thread and any complex console-specific
code will be handled there. This can cause a (usually small) delay,
but it's much better than deadlocking.
---
 mono/metadata/console-io.h    |  1 +
 mono/metadata/console-null.c  |  6 ++++++
 mono/metadata/console-unix.c  | 16 +++++++++++++++-
 mono/metadata/console-win32.c |  6 ++++++
 mono/metadata/gc.c            |  3 +++
 5 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/mono/metadata/console-io.h b/mono/metadata/console-io.h
index 46bfe44aaef..a7ef7686b68 100644
--- a/mono/metadata/console-io.h
+++ b/mono/metadata/console-io.h
@@ -19,6 +19,7 @@
 G_BEGIN_DECLS
 
 void mono_console_init (void) MONO_INTERNAL;
+void mono_console_handle_async_ops (void) MONO_INTERNAL;
 MonoBoolean ves_icall_System_ConsoleDriver_Isatty (HANDLE handle) MONO_INTERNAL;
 gint32 ves_icall_System_ConsoleDriver_InternalKeyAvailable (gint32 timeout) MONO_INTERNAL;
 MonoBoolean ves_icall_System_ConsoleDriver_SetEcho (MonoBoolean echo) MONO_INTERNAL;
diff --git a/mono/metadata/console-null.c b/mono/metadata/console-null.c
index a50b2a37d20..a2e1486c084 100644
--- a/mono/metadata/console-null.c
+++ b/mono/metadata/console-null.c
@@ -11,6 +11,7 @@
 #include <mono/metadata/object-internals.h>
 #include <mono/metadata/class-internals.h>
 #include <mono/metadata/domain-internals.h>
+#include <mono/metadata/gc-internal.h>
 
 #include <mono/metadata/console-io.h>
 #include <mono/metadata/exception.h>
@@ -20,6 +21,11 @@ mono_console_init (void)
 {
 }
 
+void
+mono_console_handle_async_ops (void)
+{
+}
+
 MonoBoolean
 ves_icall_System_ConsoleDriver_Isatty (HANDLE handle)
 {
diff --git a/mono/metadata/console-unix.c b/mono/metadata/console-unix.c
index a6c86d12718..aae513f1a02 100644
--- a/mono/metadata/console-unix.c
+++ b/mono/metadata/console-unix.c
@@ -28,6 +28,7 @@
 #include <mono/metadata/object-internals.h>
 #include <mono/metadata/class-internals.h>
 #include <mono/metadata/domain-internals.h>
+#include <mono/metadata/gc-internal.h>
 #include <mono/metadata/metadata.h>
 #include <mono/metadata/threadpool.h>
 
@@ -231,6 +232,7 @@ do_console_cancel_event (void)
 	MonoMethod *im;
 	MonoVTable *vtable;
 
+	/* FIXME: this should likely iterate all the domains, instead */
 	if (!domain->domain)
 		return;
 
@@ -258,6 +260,17 @@ do_console_cancel_event (void)
 	mono_thread_pool_add ((MonoObject *) load_value, msg, NULL, NULL);
 }
 
+static int need_cancel = FALSE;
+/* this is executed from the finalizer thread */
+void
+mono_console_handle_async_ops (void)
+{
+	if (need_cancel) {
+		need_cancel = FALSE;
+		do_console_cancel_event ();
+	}
+}
+
 static gboolean in_sigint;
 static void
 sigint_handler (int signo)
@@ -270,7 +283,8 @@ sigint_handler (int signo)
 
 	in_sigint = TRUE;
 	save_errno = errno;
-	do_console_cancel_event ();
+	need_cancel = TRUE;
+	mono_gc_finalize_notify ();
 	errno = save_errno;
 	in_sigint = FALSE;
 }
diff --git a/mono/metadata/console-win32.c b/mono/metadata/console-win32.c
index 56180991796..6b940f3edfb 100644
--- a/mono/metadata/console-win32.c
+++ b/mono/metadata/console-win32.c
@@ -24,6 +24,7 @@
 #include <mono/metadata/object-internals.h>
 #include <mono/metadata/class-internals.h>
 #include <mono/metadata/domain-internals.h>
+#include <mono/metadata/gc-internal.h>
 #include <mono/metadata/metadata.h>
 #include <mono/metadata/threadpool.h>
 
@@ -35,6 +36,11 @@ mono_console_init (void)
 {
 }
 
+void
+mono_console_handle_async_ops (void)
+{
+}
+
 MonoBoolean
 ves_icall_System_ConsoleDriver_Isatty (HANDLE handle)
 {
diff --git a/mono/metadata/gc.c b/mono/metadata/gc.c
index 718fdbf05e7..83064485e73 100644
--- a/mono/metadata/gc.c
+++ b/mono/metadata/gc.c
@@ -27,6 +27,7 @@
 #include <mono/metadata/gc-internal.h>
 #include <mono/metadata/marshal.h> /* for mono_delegate_free_ftnptr () */
 #include <mono/metadata/attach.h>
+#include <mono/metadata/console-io.h>
 #include <mono/utils/mono-semaphore.h>
 
 #ifndef HOST_WIN32
@@ -1043,6 +1044,8 @@ finalizer_thread (gpointer unused)
 		WaitForSingleObjectEx (finalizer_event, INFINITE, FALSE);
 #endif
 
+		mono_console_handle_async_ops ();
+
 #ifndef DISABLE_ATTACH
 		mono_attach_maybe_start ();
 #endif
-- 
2.25.1