Re: [PATCH 7/8] libdiskfs: register passive translator startups

[Samuel Thibault]

Justus Winter, le Sun 12 Jan 2014 20:08:44 +0100, a écrit :
> Detect passive translator startup and add the resulting active
> translator to the list of active translators.
> 
> Note that newpi is properly deallocated in the function epilogue.

Ack.

> * libdiskfs/dir-lookup.c (diskfs_S_dir_lookup): Detect and register
>   passive translator startup.
> ---
>  libdiskfs/dir-lookup.c | 41 ++++++++++++++++++++++++++++++++++++++---
>  1 file changed, 38 insertions(+), 3 deletions(-)
> 
> diff --git a/libdiskfs/dir-lookup.c b/libdiskfs/dir-lookup.c
> index 86116e3..3950bf9 100644
> --- a/libdiskfs/dir-lookup.c
> +++ b/libdiskfs/dir-lookup.c
> @@ -1,6 +1,6 @@
>  /* libdiskfs implementation of fs.defs:dir_lookup
>     Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001,
> -     2002, 2008, 2013 Free Software Foundation, Inc.
> +     2002, 2008, 2013, 2014 Free Software Foundation, Inc.
>  
>     This program is free software; you can redistribute it and/or
>     modify it under the terms of the GNU General Public License as
> @@ -74,6 +74,10 @@ diskfs_S_dir_lookup (struct protid *dircred,
>    if (! relpath)
>      return ENOMEM;
>  
> +  /* Keep a pointer to the start of the path for length
> +     calculations.  */
> +  char *path_start = path;
> +
>    *returned_port_poly = MACH_MSG_TYPE_MAKE_SEND;
>    *retry = FS_RETRY_NORMAL;
>    retryname[0] = '\0';
> @@ -274,11 +278,16 @@ diskfs_S_dir_lookup (struct protid *dircred,
>           goto out;
>  
>         dirport = ports_get_send_right (newpi);
> -       ports_port_deref (newpi);
> -       newpi = 0;
>         if (np != dnp)
>           pthread_mutex_unlock (&dnp->lock);
>  
> +       /* Check if an active translator is currently running.  If
> +          not, fshelp_fetch_root will start one.  In that case, we
> +          need to register it in the list of active
> +          translators.  */
> +       boolean_t register_translator =
> +         np->transbox.active == MACH_PORT_NULL;
> +
>         error = fshelp_fetch_root (&np->transbox, dircred->po,
>                                    dirport, dircred->user,
>                                    lastcomp ? flags : 0,
> @@ -301,9 +310,35 @@ diskfs_S_dir_lookup (struct protid *dircred,
>                 *end++ = '/';
>                 strcpy (end, nextname);
>               }
> +
> +           if (register_translator)
> +             {
> +               char *translator_path = strdupa (relpath);
> +               if (nextname != NULL)
> +                 {
> +                   /* This was not the last path component.
> +                      NEXTNAME points to the next component, locate
> +                      the end of the current component and use it
> +                      to trim TRANSLATOR_PATH.  */
> +                   char *end = nextname;
> +                   while (*end != 0)
> +                     end--;
> +                   translator_path[end - path_start] = '\0';
> +                 }
> +
> +               error = fshelp_set_active_translator (&newpi->pi,
> +                                                     translator_path,
> +                                                     np->transbox.active);
> +               if (error)
> +                 goto out;
> +             }
> +
>             goto out;
>           }
>  
> +       ports_port_deref (newpi);
> +       newpi = NULL;
> +
>         /* ENOENT means there was a hiccup, and the translator
>            vanished while NP was unlocked inside fshelp_fetch_root.
>            Reacquire the locks, and continue as normal. */
> -- 
> 1.8.5.2
> 

-- 
Samuel
<h> t: bah c'est tendre le pattern pour se faire matcher, hein