fix mfs/isofs signal handling

servers/iso9660fs/glo.h

@@ -28,6 +28,8 @@ EXTERN char user_path[PATH_MAX+1];  /* pathname to be processed */
 EXTERN char *vfs_slink_storage;
 EXTERN int symloop;
 
+EXTERN int unmountdone;
+
 EXTERN dev_t fs_dev;    /* the device that is handled by this FS proc */
 EXTERN char fs_dev_label[16]; /* Name of the device driver that is handled */
 

servers/iso9660fs/main.c

@@ -14,6 +14,7 @@ FORWARD _PROTOTYPE(void get_work, (message *m_in)			);
 /* SEF functions and variables. */
 FORWARD _PROTOTYPE( void sef_local_startup, (void) );
 FORWARD _PROTOTYPE( int sef_cb_init_fresh, (int type, sef_init_info_t *info) );
+FORWARD _PROTOTYPE( void sef_cb_signal_handler, (int signo) );
 
 /*===========================================================================*
  *				main                                         *
@@ -71,6 +72,9 @@ PRIVATE void sef_local_startup()
 
   /* No live update support for now. */
 
+  /* Register signal callbacks. */
+  sef_setcb_signal_handler(sef_cb_signal_handler);
+
   /* Let SEF perform startup. */
   sef_startup();
 }
@@ -100,6 +104,22 @@ PRIVATE int sef_cb_init_fresh(int type, sef_init_info_t *info)
    return(OK);
 }
 
+/*===========================================================================*
+ *				sef_cb_signal_handler			     *
+ *===========================================================================*/
+PRIVATE void sef_cb_signal_handler(int signo)
+{
+  /* Only check for termination signal, ignore anything else. */
+  if (signo != SIGTERM) return;
+
+  /* No need to do a sync, as this is a read-only file system. */
+
+  /* If the file system has already been unmounted, exit immediately.
+   * We might not get another message.
+   */
+  if (unmountdone) exit(0);
+}
+
 /*===========================================================================*
  *				get_work                                     *
  *===========================================================================*/

servers/iso9660fs/mount.c

@@ -101,6 +101,7 @@ PUBLIC int fs_mountpoint()
 PUBLIC int fs_unmount(void) {
   release_v_pri(&v_pri);	/* Release the super block */
   dev_close(driver_endpoints[(fs_dev >> MAJOR) & BYTE].driver_e, fs_dev);
+  unmountdone = TRUE;
   return(OK);
 }
 

servers/mfs/main.c

@@ -133,6 +133,11 @@ PRIVATE void sef_cb_signal_handler(int signo)
 
   exitsignaled = 1;
   fs_sync();
+
+  /* If unmounting has already been performed, exit immediately.
+   * We might not get another message.
+   */
+  if (unmountdone) exit(0);
 }
 
 /*===========================================================================*