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authorMichael I. Bushnell <mib@gnu.org>1993-12-03 01:49:44 +0000
committerMichael I. Bushnell <mib@gnu.org>1993-12-03 01:49:44 +0000
commita7a6a6d433f7386ca80bec0290fc6ea6bf283dcc (patch)
treeed6e525f52a0ec712ad8c4a6e4cda6000ba210b0
parent0ee063a2af7fab1b8b18ee795c25bed740b4a821 (diff)
Initial revision
-rw-r--r--libiohelp/handle_io_get_conch.c56
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);
+}