perl: Add binding for guestfs_event_to_string.

generator/perl.ml

@@ -39,7 +39,9 @@ let rec generate_perl_xs () =
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 #include <inttypes.h>
+#include <errno.h>
 
 #include \"EXTERN.h\"
 #include \"perl.h\"
@@ -294,6 +296,20 @@ PREINIT:
         guestfs_delete_event_callback (g, event_handle);
       }
 
+SV *
+event_to_string (event_bitmask)
+      int event_bitmask;
+PREINIT:
+      char *str;
+   CODE:
+      str = guestfs_event_to_string (event_bitmask);
+      if (str == NULL)
+        croak (\"%%s\", strerror (errno));
+      RETVAL = newSVpv (str, 0);
+      free (str);
+ OUTPUT:
+      RETVAL
+
 SV *
 last_errno (g)
       guestfs_h *g;
@@ -829,6 +845,13 @@ this function.
 This removes the callback which was previously registered using
 C<set_event_callback>.
 
+=item $str = Sys::Guestfs::event_to_string ($events);
+
+C<$events> is either a single event or a bitmask of events.
+This returns a printable string, useful for debugging.
+
+Note that this is a class function, not a method.
+
 =item $errnum = $g->last_errno ();
 
 This returns the last error number (errno) that happened on the

perl/t/400-events.t

@@ -34,8 +34,9 @@ sub log_callback {
 
     # We don't get to see this output because it is eaten up by the
     # test harness, but generate it anyway.
-    printf("perl event logged: event=0x%x eh=%d buf='%s' array=[%s]\n",
-           $ev, $eh, $buf, join (", ", @$array));
+    printf("perl event logged: event=%s eh=%d buf='%s' array=[%s]\n",
+           Sys::Guestfs->event_to_string ($ev),
+           $eh, $buf, join (", ", @$array));
 }
 
 my $close_invoked = 0;