mutex.c 8.4 KB
Newer Older
Alexandre Julliard's avatar
Alexandre Julliard committed
1 2 3 4
/*
 * Server-side mutex management
 *
 * Copyright (C) 1998 Alexandre Julliard
5 6 7 8 9 10 11 12 13 14 15 16 17
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
18
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
Alexandre Julliard's avatar
Alexandre Julliard committed
19 20
 */

21 22 23
#include "config.h"
#include "wine/port.h"

Alexandre Julliard's avatar
Alexandre Julliard committed
24 25 26
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
27
#include <stdarg.h>
Alexandre Julliard's avatar
Alexandre Julliard committed
28

29 30
#include "ntstatus.h"
#define WIN32_NO_STATUS
31
#include "windef.h"
32
#include "winternl.h"
33 34 35

#include "handle.h"
#include "thread.h"
36
#include "request.h"
37
#include "security.h"
Alexandre Julliard's avatar
Alexandre Julliard committed
38 39 40 41 42 43 44

struct mutex
{
    struct object  obj;             /* object header */
    struct thread *owner;           /* mutex owner */
    unsigned int   count;           /* recursion count */
    int            abandoned;       /* has it been abandoned? */
45
    struct list    entry;           /* entry in owner thread mutex list */
Alexandre Julliard's avatar
Alexandre Julliard committed
46 47
};

48
static void mutex_dump( struct object *obj, int verbose );
49
static struct object_type *mutex_get_type( struct object *obj );
50
static int mutex_signaled( struct object *obj, struct wait_queue_entry *entry );
51
static void mutex_satisfied( struct object *obj, struct wait_queue_entry *entry );
52
static unsigned int mutex_map_access( struct object *obj, unsigned int access );
53
static void mutex_destroy( struct object *obj );
54
static int mutex_signal( struct object *obj, unsigned int access );
Alexandre Julliard's avatar
Alexandre Julliard committed
55 56 57

static const struct object_ops mutex_ops =
{
58 59
    sizeof(struct mutex),      /* size */
    mutex_dump,                /* dump */
60
    mutex_get_type,            /* get_type */
61 62 63 64
    add_queue,                 /* add_queue */
    remove_queue,              /* remove_queue */
    mutex_signaled,            /* signaled */
    mutex_satisfied,           /* satisfied */
65
    mutex_signal,              /* signal */
66
    no_get_fd,                 /* get_fd */
67
    mutex_map_access,          /* map_access */
68 69
    default_get_sd,            /* get_sd */
    default_set_sd,            /* set_sd */
70
    no_lookup_name,            /* lookup_name */
71 72
    directory_link_name,       /* link_name */
    default_unlink_name,       /* unlink_name */
73
    no_open_file,              /* open_file */
74
    no_close_handle,           /* close_handle */
75
    mutex_destroy              /* destroy */
Alexandre Julliard's avatar
Alexandre Julliard committed
76 77 78
};


79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101
/* grab a mutex for a given thread */
static void do_grab( struct mutex *mutex, struct thread *thread )
{
    assert( !mutex->count || (mutex->owner == thread) );

    if (!mutex->count++)  /* FIXME: avoid wrap-around */
    {
        assert( !mutex->owner );
        mutex->owner = thread;
        list_add_head( &thread->mutex_list, &mutex->entry );
    }
}

/* release a mutex once the recursion count is 0 */
static void do_release( struct mutex *mutex )
{
    assert( !mutex->count );
    /* remove the mutex from the thread list of owned mutexes */
    list_remove( &mutex->entry );
    mutex->owner = NULL;
    wake_up( &mutex->obj, 0 );
}

102
static struct mutex *create_mutex( struct object *root, const struct unicode_str *name,
103
                                   unsigned int attr, int owned, const struct security_descriptor *sd )
Alexandre Julliard's avatar
Alexandre Julliard committed
104 105 106
{
    struct mutex *mutex;

107
    if ((mutex = create_named_object( root, &mutex_ops, name, attr, sd )))
Alexandre Julliard's avatar
Alexandre Julliard committed
108
    {
109
        if (get_error() != STATUS_OBJECT_NAME_EXISTS)
110 111 112 113 114
        {
            /* initialize it if it didn't already exist */
            mutex->count = 0;
            mutex->owner = NULL;
            mutex->abandoned = 0;
115
            if (owned) do_grab( mutex, current );
116
        }
Alexandre Julliard's avatar
Alexandre Julliard committed
117
    }
118
    return mutex;
Alexandre Julliard's avatar
Alexandre Julliard committed
119 120 121 122
}

void abandon_mutexes( struct thread *thread )
{
123 124 125
    struct list *ptr;

    while ((ptr = list_head( &thread->mutex_list )) != NULL)
Alexandre Julliard's avatar
Alexandre Julliard committed
126
    {
127
        struct mutex *mutex = LIST_ENTRY( ptr, struct mutex, entry );
Alexandre Julliard's avatar
Alexandre Julliard committed
128 129 130
        assert( mutex->owner == thread );
        mutex->count = 0;
        mutex->abandoned = 1;
131
        do_release( mutex );
Alexandre Julliard's avatar
Alexandre Julliard committed
132 133 134
    }
}

135
static void mutex_dump( struct object *obj, int verbose )
Alexandre Julliard's avatar
Alexandre Julliard committed
136 137 138
{
    struct mutex *mutex = (struct mutex *)obj;
    assert( obj->ops == &mutex_ops );
139
    fprintf( stderr, "Mutex count=%u owner=%p\n", mutex->count, mutex->owner );
Alexandre Julliard's avatar
Alexandre Julliard committed
140 141
}

142 143 144 145 146 147 148
static struct object_type *mutex_get_type( struct object *obj )
{
    static const WCHAR name[] = {'M','u','t','a','n','t'};
    static const struct unicode_str str = { name, sizeof(name) };
    return get_object_type( &str );
}

149
static int mutex_signaled( struct object *obj, struct wait_queue_entry *entry )
Alexandre Julliard's avatar
Alexandre Julliard committed
150 151 152
{
    struct mutex *mutex = (struct mutex *)obj;
    assert( obj->ops == &mutex_ops );
153
    return (!mutex->count || (mutex->owner == get_wait_queue_thread( entry )));
Alexandre Julliard's avatar
Alexandre Julliard committed
154 155
}

156
static void mutex_satisfied( struct object *obj, struct wait_queue_entry *entry )
Alexandre Julliard's avatar
Alexandre Julliard committed
157 158 159 160
{
    struct mutex *mutex = (struct mutex *)obj;
    assert( obj->ops == &mutex_ops );

161
    do_grab( mutex, get_wait_queue_thread( entry ));
162
    if (mutex->abandoned) make_wait_abandoned( entry );
Alexandre Julliard's avatar
Alexandre Julliard committed
163 164 165
    mutex->abandoned = 0;
}

166 167
static unsigned int mutex_map_access( struct object *obj, unsigned int access )
{
168
    if (access & GENERIC_READ)    access |= STANDARD_RIGHTS_READ | MUTANT_QUERY_STATE;
169 170
    if (access & GENERIC_WRITE)   access |= STANDARD_RIGHTS_WRITE;
    if (access & GENERIC_EXECUTE) access |= STANDARD_RIGHTS_EXECUTE | SYNCHRONIZE;
171 172 173 174
    if (access & GENERIC_ALL)     access |= STANDARD_RIGHTS_ALL | MUTEX_ALL_ACCESS;
    return access & ~(GENERIC_READ | GENERIC_WRITE | GENERIC_EXECUTE | GENERIC_ALL);
}

175 176 177 178 179
static int mutex_signal( struct object *obj, unsigned int access )
{
    struct mutex *mutex = (struct mutex *)obj;
    assert( obj->ops == &mutex_ops );

180
    if (!(access & SYNCHRONIZE))
181 182 183 184 185 186 187 188 189 190 191 192 193
    {
        set_error( STATUS_ACCESS_DENIED );
        return 0;
    }
    if (!mutex->count || (mutex->owner != current))
    {
        set_error( STATUS_MUTANT_NOT_OWNED );
        return 0;
    }
    if (!--mutex->count) do_release( mutex );
    return 1;
}

194 195 196 197 198 199 200 201 202 203
static void mutex_destroy( struct object *obj )
{
    struct mutex *mutex = (struct mutex *)obj;
    assert( obj->ops == &mutex_ops );

    if (!mutex->count) return;
    mutex->count = 0;
    do_release( mutex );
}

204 205 206
/* create a mutex */
DECL_HANDLER(create_mutex)
{
207
    struct mutex *mutex;
208
    struct unicode_str name;
209
    struct object *root;
210
    const struct security_descriptor *sd;
211
    const struct object_attributes *objattr = get_req_object_attributes( &sd, &name, &root );
212

213
    if (!objattr) return;
214

215
    if ((mutex = create_mutex( root, &name, objattr->attributes, req->owned, sd )))
216
    {
217
        if (get_error() == STATUS_OBJECT_NAME_EXISTS)
218
            reply->handle = alloc_handle( current->process, mutex, req->access, objattr->attributes );
219
        else
220 221
            reply->handle = alloc_handle_no_access_check( current->process, mutex,
                                                          req->access, objattr->attributes );
222
        release_object( mutex );
223
    }
224 225

    if (root) release_object( root );
226 227 228 229 230
}

/* open a handle to a mutex */
DECL_HANDLER(open_mutex)
{
231
    struct unicode_str name = get_req_unicode_str();
232

233 234
    reply->handle = open_object( current->process, req->rootdir, req->access,
                                 &mutex_ops, &name, req->attributes );
235 236 237 238 239
}

/* release a mutex */
DECL_HANDLER(release_mutex)
{
240 241 242
    struct mutex *mutex;

    if ((mutex = (struct mutex *)get_handle_obj( current->process, req->handle,
243
                                                 0, &mutex_ops )))
244
    {
245
        if (!mutex->count || (mutex->owner != current)) set_error( STATUS_MUTANT_NOT_OWNED );
246 247 248 249 250
        else
        {
            reply->prev_count = mutex->count;
            if (!--mutex->count) do_release( mutex );
        }
251 252
        release_object( mutex );
    }
253
}
254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269

/* return details about the mutex */
DECL_HANDLER(query_mutex)
{
    struct mutex *mutex;

    if ((mutex = (struct mutex *)get_handle_obj( current->process, req->handle,
                                                 MUTANT_QUERY_STATE, &mutex_ops )))
    {
        reply->count = mutex->count;
        reply->owned = (mutex->owner == current);
        reply->abandoned = mutex->abandoned;

        release_object( mutex );
    }
}