diff options
Diffstat (limited to 'libiohelp')
-rw-r--r-- | libiohelp/handle_io_get_conch.c | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/libiohelp/handle_io_get_conch.c b/libiohelp/handle_io_get_conch.c new file mode 100644 index 00000000..249e9e46 --- /dev/null +++ b/libiohelp/handle_io_get_conch.c @@ -0,0 +1,56 @@ +/* + Copyright (C) 1993 Free Software Foundation + + This program is free software; you can redistribute it and/or + modify it under the terms of the GNU General Public License as + published by the Free Software Foundation; either version 2, or (at + your option) any later version. + + This program is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ + + +#include <libioserver.h> + +error_t +handle_io_get_conch (struct conch *c, void *user, struct shared *user_sh) +{ + error_t error; + + mutex_lock (&c->lock); + + if (c->holder == user) + { + if (user_sh->conch_status != USER_HAS_NOT_CONCH) + error = fetch_shared_data (user); + else + user_sh->accessed = user_sh->written = 0; + + if (!error) + error = put_shared_data (user); + if (!error) + user_sh->conch_status = USER_HAS_CONCH; + } + else + { + error = _libioserver_internal_get_conch (c); + + if (!error) + { + c->holder = user; + c->holder_shared_page = user_sh; + user_sh->conch_status == USER_HAS_NOT_CONCH + user_sh->accessed = user_sh->written = 0; + user_sh->conch_status = USER_HAS_CONCH; + put_shared_data (user); + } + } + + mutex_unlock (&c->lock); +} |