fix SIGINT handling thread dependency

src/racket/include/mzwin.def

@@ -35,6 +35,8 @@ EXPORTS
  scheme_kill_thread
  scheme_break_thread
  scheme_break_main_thread
+ scheme_break_main_thread_at
+ scheme_get_main_thread_break_handle
  scheme_set_break_main_target
  scheme_thread_block
  scheme_thread_block_enable_break

src/racket/include/mzwin3m.def

@@ -35,6 +35,8 @@ EXPORTS
  scheme_kill_thread
  scheme_break_thread
  scheme_break_main_thread
+ scheme_break_main_thread_at
+ scheme_get_main_thread_break_handle
  scheme_set_break_main_target
  scheme_thread_block
  scheme_thread_block_enable_break

src/racket/include/racket.exp

@@ -33,6 +33,8 @@ scheme_thread_w_details
 scheme_kill_thread
 scheme_break_thread
 scheme_break_main_thread
+scheme_break_main_thread_at
+scheme_get_main_thread_break_handle
 scheme_set_break_main_target
 scheme_thread_block
 scheme_thread_block_enable_break

src/racket/include/racket3m.exp

@@ -33,6 +33,8 @@ scheme_thread_w_details
 scheme_kill_thread
 scheme_break_thread
 scheme_break_main_thread
+scheme_break_main_thread_at
+scheme_get_main_thread_break_handle
 scheme_set_break_main_target
 scheme_thread_block
 scheme_thread_block_enable_break

src/racket/main.c

@@ -172,10 +172,13 @@ extern Scheme_Object *scheme_initialize(Scheme_Env *env);
 
 #ifndef NO_USER_BREAK_HANDLER
 
+static void *break_handle;
+static void *signal_handle;
+
 static void user_break_hit(int ignore)
 {
-  scheme_break_main_thread();
-  scheme_signal_received();
+  scheme_break_main_thread_at(break_handle);
+  scheme_signal_received_at(signal_handle);
 
 #  ifdef SIGSET_NEEDS_REINSTALL
   MZ_SIGSET(SIGINT, user_break_hit);
@@ -314,6 +317,8 @@ static int main_after_stack(void *data)
 #endif
 
 #ifndef NO_USER_BREAK_HANDLER
+ break_handle = scheme_get_main_thread_break_handle();
+ signal_handle = scheme_get_signal_handle();
  MZ_SIGSET(SIGINT, user_break_hit);
 #endif
 

src/racket/src/schemef.h

@@ -99,6 +99,8 @@ MZ_EXTERN Scheme_Object *scheme_thread_w_details(Scheme_Object *thunk,
 MZ_EXTERN void scheme_kill_thread(Scheme_Thread *p);
 MZ_EXTERN void scheme_break_thread(Scheme_Thread *p);
 MZ_EXTERN void scheme_break_main_thread();
+MZ_EXTERN void scheme_break_main_thread_at(void *);
+MZ_EXTERN void *scheme_get_main_thread_break_handle();
 MZ_EXTERN void scheme_set_break_main_target(Scheme_Thread *p);
 
 MZ_EXTERN void scheme_thread_block(float sleep_time);

src/racket/src/schemex.h

@@ -81,6 +81,8 @@ Scheme_Object *(*scheme_thread_w_details)(Scheme_Object *thunk,
 void (*scheme_kill_thread)(Scheme_Thread *p);
 void (*scheme_break_thread)(Scheme_Thread *p);
 void (*scheme_break_main_thread)();
+void (*scheme_break_main_thread_at)(void *);
+void *(*scheme_get_main_thread_break_handle)();
 void (*scheme_set_break_main_target)(Scheme_Thread *p);
 void (*scheme_thread_block)(float sleep_time);
 void (*scheme_thread_block_enable_break)(float sleep_time, int enable);

src/racket/src/schemex.inc

@@ -41,6 +41,8 @@
   scheme_extension_table->scheme_kill_thread = scheme_kill_thread;
   scheme_extension_table->scheme_break_thread = scheme_break_thread;
   scheme_extension_table->scheme_break_main_thread = scheme_break_main_thread;
+  scheme_extension_table->scheme_break_main_thread_at = scheme_break_main_thread_at;
+  scheme_extension_table->scheme_get_main_thread_break_handle = scheme_get_main_thread_break_handle;
   scheme_extension_table->scheme_set_break_main_target = scheme_set_break_main_target;
   scheme_extension_table->scheme_thread_block = scheme_thread_block;
   scheme_extension_table->scheme_thread_block_enable_break = scheme_thread_block_enable_break;

src/racket/src/schemexm.h

@@ -41,6 +41,8 @@
 #define scheme_kill_thread (scheme_extension_table->scheme_kill_thread)
 #define scheme_break_thread (scheme_extension_table->scheme_break_thread)
 #define scheme_break_main_thread (scheme_extension_table->scheme_break_main_thread)
+#define scheme_break_main_thread_at (scheme_extension_table->scheme_break_main_thread_at)
+#define scheme_get_main_thread_break_handle (scheme_extension_table->scheme_get_main_thread_break_handle)
 #define scheme_set_break_main_target (scheme_extension_table->scheme_set_break_main_target)
 #define scheme_thread_block (scheme_extension_table->scheme_thread_block)
 #define scheme_thread_block_enable_break (scheme_extension_table->scheme_thread_block_enable_break)

src/racket/src/thread.c

@@ -3981,14 +3981,26 @@ static void exit_or_escape(Scheme_Thread *p)
   select_thread();
 }
 
-void scheme_break_main_thread()
+void scheme_break_main_thread_at(void *p)
 /* This function can be called from an interrupt handler. 
    On some platforms, it will even be called from multiple
    OS threads. In the case of multiple threads, there's a
    tiny chance that a single Ctl-C will trigger multiple
    break exceptions. */
 {
-  delayed_break_ready = 1;
+  *(volatile short *)p = 1;
+}
+
+void scheme_break_main_thread()
+/* Calling this function from an arbitary
+   thread is dangerous when therad locals are enabled. */
+{
+  scheme_break_main_thread_at((void *)&delayed_break_ready);
+}
+
+void *scheme_get_main_thread_break_handle()
+{
+  return (void *)&delayed_break_ready;
 }
 
 void scheme_set_break_main_target(Scheme_Thread *p)