2 * Server-side mutex management
4 * Copyright (C) 1998 Alexandre Julliard
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 #include "wine/port.h"
36 struct object obj; /* object header */
37 struct thread *owner; /* mutex owner */
38 unsigned int count; /* recursion count */
39 int abandoned; /* has it been abandoned? */
44 static void mutex_dump( struct object *obj, int verbose );
45 static int mutex_signaled( struct object *obj, struct thread *thread );
46 static int mutex_satisfied( struct object *obj, struct thread *thread );
47 static void mutex_destroy( struct object *obj );
49 static const struct object_ops mutex_ops =
51 sizeof(struct mutex), /* size */
52 mutex_dump, /* dump */
53 add_queue, /* add_queue */
54 remove_queue, /* remove_queue */
55 mutex_signaled, /* signaled */
56 mutex_satisfied, /* satisfied */
57 no_get_fd, /* get_fd */
58 no_get_file_info, /* get_file_info */
59 mutex_destroy /* destroy */
63 static struct mutex *create_mutex( const WCHAR *name, size_t len, int owned )
67 if ((mutex = create_named_object( sync_namespace, &mutex_ops, name, len )))
69 if (get_error() != STATUS_OBJECT_NAME_COLLISION)
71 /* initialize it if it didn't already exist */
75 mutex->next = mutex->prev = NULL;
76 if (owned) mutex_satisfied( &mutex->obj, current );
82 /* release a mutex once the recursion count is 0 */
83 static void do_release( struct mutex *mutex )
85 assert( !mutex->count );
86 /* remove the mutex from the thread list of owned mutexes */
87 if (mutex->next) mutex->next->prev = mutex->prev;
88 if (mutex->prev) mutex->prev->next = mutex->next;
89 else mutex->owner->mutex = mutex->next;
91 mutex->next = mutex->prev = NULL;
92 wake_up( &mutex->obj, 0 );
95 void abandon_mutexes( struct thread *thread )
99 struct mutex *mutex = thread->mutex;
100 assert( mutex->owner == thread );
102 mutex->abandoned = 1;
107 static void mutex_dump( struct object *obj, int verbose )
109 struct mutex *mutex = (struct mutex *)obj;
110 assert( obj->ops == &mutex_ops );
111 fprintf( stderr, "Mutex count=%u owner=%p ", mutex->count, mutex->owner );
112 dump_object_name( &mutex->obj );
113 fputc( '\n', stderr );
116 static int mutex_signaled( struct object *obj, struct thread *thread )
118 struct mutex *mutex = (struct mutex *)obj;
119 assert( obj->ops == &mutex_ops );
120 return (!mutex->count || (mutex->owner == thread));
123 static int mutex_satisfied( struct object *obj, struct thread *thread )
125 struct mutex *mutex = (struct mutex *)obj;
126 assert( obj->ops == &mutex_ops );
127 assert( !mutex->count || (mutex->owner == thread) );
129 if (!mutex->count++) /* FIXME: avoid wrap-around */
131 assert( !mutex->owner );
132 mutex->owner = thread;
134 if ((mutex->next = thread->mutex)) mutex->next->prev = mutex;
135 thread->mutex = mutex;
137 if (!mutex->abandoned) return 0;
138 mutex->abandoned = 0;
142 static void mutex_destroy( struct object *obj )
144 struct mutex *mutex = (struct mutex *)obj;
145 assert( obj->ops == &mutex_ops );
147 if (!mutex->count) return;
153 DECL_HANDLER(create_mutex)
158 if ((mutex = create_mutex( get_req_data(), get_req_data_size(), req->owned )))
160 reply->handle = alloc_handle( current->process, mutex, MUTEX_ALL_ACCESS, req->inherit );
161 release_object( mutex );
165 /* open a handle to a mutex */
166 DECL_HANDLER(open_mutex)
168 reply->handle = open_object( sync_namespace, get_req_data(), get_req_data_size(),
169 &mutex_ops, req->access, req->inherit );
172 /* release a mutex */
173 DECL_HANDLER(release_mutex)
177 if ((mutex = (struct mutex *)get_handle_obj( current->process, req->handle,
178 MUTEX_MODIFY_STATE, &mutex_ops )))
180 if (!mutex->count || (mutex->owner != current)) set_error( STATUS_MUTANT_NOT_OWNED );
181 else if (!--mutex->count) do_release( mutex );
182 release_object( mutex );