boehm-gc and sigwait() ?

[Bryce McKinlay]

I've been trying to get libgcj to exit more cleanly on Ctrl-C, by
blocking the master thread on sigwait() and calling exit() on SIGINT.
See patch below. This works well, except seem to cause a hang in
boehm-gc when a collection occurs.

Can anyone see a way around this problem?

regards

  [ bryce ]


Index: prims.cc
===================================================================
RCS file: /cvs/java/libgcj/libjava/prims.cc,v
retrieving revision 1.13
diff -u -r1.13 prims.cc
--- prims.cc 1999/11/05 17:34:32 1.13
+++ prims.cc 1999/11/23 06:26:01
@@ -793,7 +793,8 @@
   main_thread->start();
   _Jv_ThreadWait ();

-  java::lang::Runtime::getRuntime ()->exit (0);
+  // _Jv_ThreadWait returns only on SIGINT (Ctrl-C).
+  ::exit(1);
 }

 void
Index: posix-threads.cc
===================================================================
RCS file: /cvs/java/libgcj/libjava/posix-threads.cc,v
retrieving revision 1.13
diff -u -r1.13 posix-threads.cc
--- posix-threads.cc 1999/11/04 16:45:11 1.13
+++ posix-threads.cc 1999/11/23 06:26:01
@@ -32,6 +32,7 @@
 #include <jvm.h>
 #include <java/lang/Thread.h>
 #include <java/lang/System.h>
+#include <java/lang/Runtime.h>

 // This is used to implement thread startup.
 struct starter
@@ -53,7 +54,6 @@
 // We keep a count of all non-daemon threads which are running.  When
 // this reaches zero, _Jv_ThreadWait returns.
 static pthread_mutex_t daemon_mutex;
-static pthread_cond_t daemon_cond;
 static int non_daemon_count;

 // The signal to use when interrupting a thread.
@@ -260,7 +260,6 @@
   pthread_key_create (&_Jv_ThreadKey, NULL);
   pthread_key_create (&_Jv_ThreadDataKey, NULL);
   pthread_mutex_init (&daemon_mutex, NULL);
-  pthread_cond_init (&daemon_cond, 0);
   non_daemon_count = 0;

   // Arrange for the interrupt signal to interrupt system calls.
@@ -270,8 +269,7 @@
   act.sa_flags = 0;
   sigaction (INTR, &act, NULL);

-  // Arrange for SIGINT to be blocked to all threads.  It is only
-  // deliverable to the master thread.
+  // Arrange for SIGINT to be blocked to all threads.
   sigset_t mask;
   sigemptyset (&mask);
   sigaddset (&mask, SIGINT);
@@ -320,7 +318,7 @@
       pthread_mutex_lock (&daemon_mutex);
       --non_daemon_count;
       if (! non_daemon_count)
- pthread_cond_signal (&daemon_cond);
+ java::lang::Runtime::getRuntime ()->exit (0);
       pthread_mutex_unlock (&daemon_mutex);
     }

@@ -366,16 +364,13 @@
 void
 _Jv_ThreadWait (void)
 {
-  // Arrange for SIGINT to be delivered to the master thread.
+  // block the thread, and only return if a SIGINT occurs.
   sigset_t mask;
   sigemptyset (&mask);
   sigaddset (&mask, SIGINT);
-  pthread_sigmask (SIG_UNBLOCK, &mask, NULL);
+  int count;

-  pthread_mutex_lock (&daemon_mutex);
-  if (non_daemon_count)
-    pthread_cond_wait (&daemon_cond, &daemon_mutex);
-  pthread_mutex_unlock (&daemon_mutex);
+  sigwait(&mask, &count);
 }

 void