1.0.46.27: fix mach port leakage

[sbcl.git] / src / runtime / darwin-os.c

diff --git a/src/runtime/darwin-os.c b/src/runtime/darwin-os.c
index 4a2bef6..2d79d06 100644 (file)
--- a/src/runtime/darwin-os.c
+++ b/src/runtime/darwin-os.c
@@ -14,16 +14,20 @@
  * files for more information.
  */
 
+#include "thread.h"
 #include "sbcl.h"
 #include "globals.h"
 #include "runtime.h"
 #include <signal.h>
 #include <limits.h>
 #include <mach-o/dyld.h>
-#include "bsd-os.h"
 #include <errno.h>
 #include <dlfcn.h>
 
+#ifdef LISP_FEATURE_MACH_EXCEPTION_HANDLER
+#include <mach/mach.h>
+#endif
+
 char *
 os_get_runtime_executable_path(int external)
 {
@@ -38,3 +42,129 @@ os_get_runtime_executable_path(int external)
     return copied_string(path);
 }
 
+#ifdef LISP_FEATURE_MACH_EXCEPTION_HANDLER
+
+/* exc_server handles mach exception messages from the kernel and
+ * calls catch exception raise. We use the system-provided
+ * mach_msg_server, which, I assume, calls exc_server in a loop.
+ *
+ */
+extern boolean_t exc_server();
+
+void *
+mach_exception_handler(void *port)
+{
+  mach_msg_server(exc_server, 2048, (mach_port_t) port, 0);
+  /* mach_msg_server should never return, but it should dispatch mach
+   * exceptions to our catch_exception_raise function
+   */
+  lose("mach_msg_server returned");
+}
+
+/* Sets up the thread that will listen for mach exceptions. note that
+   the exception handlers will be run on this thread. This is
+   different from the BSD-style signal handling situation in which the
+   signal handlers run in the relevant thread directly. */
+
+mach_port_t mach_exception_handler_port_set = MACH_PORT_NULL;
+mach_port_t current_mach_task = MACH_PORT_NULL;
+
+pthread_t
+setup_mach_exception_handling_thread()
+{
+    kern_return_t ret;
+    pthread_t mach_exception_handling_thread = NULL;
+    pthread_attr_t attr;
+
+    current_mach_task = mach_task_self();
+
+    /* allocate a mach_port for this process */
+    ret = mach_port_allocate(current_mach_task,
+                             MACH_PORT_RIGHT_PORT_SET,
+                             &mach_exception_handler_port_set);
+
+    /* create the thread that will receive the mach exceptions */
+
+    FSHOW((stderr, "Creating mach_exception_handler thread!\n"));
+
+    pthread_attr_init(&attr);
+    pthread_create(&mach_exception_handling_thread,
+                   &attr,
+                   mach_exception_handler,
+                   (void*) mach_exception_handler_port_set);
+    pthread_attr_destroy(&attr);
+
+    return mach_exception_handling_thread;
+}
+
+/* tell the kernel that we want EXC_BAD_ACCESS exceptions sent to the
+   exception port (which is being listened to do by the mach
+   exception handling thread). */
+kern_return_t
+mach_thread_init(mach_port_t thread_exception_port)
+{
+    kern_return_t ret;
+    mach_port_t current_mach_thread;
+
+    /* allocate a named port for the thread */
+    FSHOW((stderr, "Allocating mach port %x\n", thread_exception_port));
+    ret = mach_port_allocate_name(current_mach_task,
+                                  MACH_PORT_RIGHT_RECEIVE,
+                                  thread_exception_port);
+    if (ret) {
+        lose("mach_port_allocate_name failed with return_code %d\n", ret);
+    }
+
+    /* establish the right for the thread_exception_port to send messages */
+    ret = mach_port_insert_right(current_mach_task,
+                                 thread_exception_port,
+                                 thread_exception_port,
+                                 MACH_MSG_TYPE_MAKE_SEND);
+    if (ret) {
+        lose("mach_port_insert_right failed with return_code %d\n", ret);
+    }
+
+    current_mach_thread = mach_thread_self();
+    ret = thread_set_exception_ports(current_mach_thread,
+                                     EXC_MASK_BAD_ACCESS | EXC_MASK_BAD_INSTRUCTION,
+                                     thread_exception_port,
+                                     EXCEPTION_DEFAULT,
+                                     THREAD_STATE_NONE);
+    if (ret) {
+        lose("thread_set_exception_ports failed with return_code %d\n", ret);
+    }
+
+    ret = mach_port_deallocate (current_mach_task, current_mach_thread);
+    if (ret) {
+        lose("mach_port_deallocate failed with return_code %d\n", ret);
+    }
+
+    ret = mach_port_move_member(current_mach_task,
+                                thread_exception_port,
+                                mach_exception_handler_port_set);
+    if (ret) {
+        lose("mach_port_move_member failed with return_code %d\n", ret);
+    }
+
+    return ret;
+}
+
+void
+setup_mach_exceptions() {
+    setup_mach_exception_handling_thread();
+    mach_thread_init(THREAD_STRUCT_TO_EXCEPTION_PORT(all_threads));
+}
+
+pid_t
+mach_fork() {
+    pid_t pid = fork();
+    if (pid == 0) {
+        setup_mach_exceptions();
+        return pid;
+    } else {
+        return pid;
+    }
+}
+
+#endif
+