server/event.c

   1 /*
   2  * Server-side event management
   3  *
   4  * Copyright (C) 1998 Alexandre Julliard
   5  *
   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.
  10  *
  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.
  15  *
  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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  19  */
  20
  21 #include "config.h"
  22
  23 #include <assert.h>
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <stdarg.h>
  27 #include <sys/types.h>
  28
  29 #include "ntstatus.h"
  30 #define WIN32_NO_STATUS
  31 #include "windef.h"
  32 #include "winternl.h"
  33
  34 #include "handle.h"
  35 #include "thread.h"
  36 #include "request.h"
  37 #include "security.h"
  38
  39 static const WCHAR event_name[] = {'E','v','e','n','t'};
  40
  41 struct type_descr event_type =
  42 {
  43     { event_name, sizeof(event_name) },   /* name */
  44     EVENT_ALL_ACCESS,                     /* valid_access */
  45     {                                     /* mapping */
  46         STANDARD_RIGHTS_READ | EVENT_QUERY_STATE,
  47         STANDARD_RIGHTS_WRITE | EVENT_MODIFY_STATE,
  48         STANDARD_RIGHTS_EXECUTE | SYNCHRONIZE,
  49         EVENT_ALL_ACCESS
  50     },
  51 };
  52
  53 struct event
  54 {
  55     struct object  obj;             /* object header */
  56     struct list    kernel_object;   /* list of kernel object pointers */
  57     int            manual_reset;    /* is it a manual reset event? */
  58     int            signaled;        /* event has been signaled */
  59 };
  60
  61 static void event_dump( struct object *obj, int verbose );
  62 static int event_signaled( struct object *obj, struct wait_queue_entry *entry );
  63 static void event_satisfied( struct object *obj, struct wait_queue_entry *entry );
  64 static int event_signal( struct object *obj, unsigned int access);
  65 static struct list *event_get_kernel_obj_list( struct object *obj );
  66
  67 static const struct object_ops event_ops =
  68 {
  69     sizeof(struct event),      /* size */
  70     &event_type,               /* type */
  71     event_dump,                /* dump */
  72     add_queue,                 /* add_queue */
  73     remove_queue,              /* remove_queue */
  74     event_signaled,            /* signaled */
  75     event_satisfied,           /* satisfied */
  76     event_signal,              /* signal */
  77     no_get_fd,                 /* get_fd */
  78     default_map_access,        /* map_access */
  79     default_get_sd,            /* get_sd */
  80     default_set_sd,            /* set_sd */
  81     default_get_full_name,     /* get_full_name */
  82     no_lookup_name,            /* lookup_name */
  83     directory_link_name,       /* link_name */
  84     default_unlink_name,       /* unlink_name */
  85     no_open_file,              /* open_file */
  86     event_get_kernel_obj_list, /* get_kernel_obj_list */
  87     no_close_handle,           /* close_handle */
  88     no_destroy                 /* destroy */
  89 };
  90
  91
  92 static const WCHAR keyed_event_name[] = {'K','e','y','e','d','E','v','e','n','t'};
  93
  94 struct type_descr keyed_event_type =
  95 {
  96     { keyed_event_name, sizeof(keyed_event_name) },   /* name */
  97     KEYEDEVENT_ALL_ACCESS | SYNCHRONIZE,              /* valid_access */
  98     {                                                 /* mapping */
  99         STANDARD_RIGHTS_READ | KEYEDEVENT_WAIT,
 100         STANDARD_RIGHTS_WRITE | KEYEDEVENT_WAKE,
 101         STANDARD_RIGHTS_EXECUTE,
 102         KEYEDEVENT_ALL_ACCESS
 103     },
 104 };
 105
 106 struct keyed_event
 107 {
 108     struct object  obj;             /* object header */
 109 };
 110
 111 static void keyed_event_dump( struct object *obj, int verbose );
 112 static int keyed_event_signaled( struct object *obj, struct wait_queue_entry *entry );
 113
 114 static const struct object_ops keyed_event_ops =
 115 {
 116     sizeof(struct keyed_event),  /* size */
 117     &keyed_event_type,           /* type */
 118     keyed_event_dump,            /* dump */
 119     add_queue,                   /* add_queue */
 120     remove_queue,                /* remove_queue */
 121     keyed_event_signaled,        /* signaled */
 122     no_satisfied,                /* satisfied */
 123     no_signal,                   /* signal */
 124     no_get_fd,                   /* get_fd */
 125     default_map_access,          /* map_access */
 126     default_get_sd,              /* get_sd */
 127     default_set_sd,              /* set_sd */
 128     default_get_full_name,       /* get_full_name */
 129     no_lookup_name,              /* lookup_name */
 130     directory_link_name,         /* link_name */
 131     default_unlink_name,         /* unlink_name */
 132     no_open_file,                /* open_file */
 133     no_kernel_obj_list,          /* get_kernel_obj_list */
 134     no_close_handle,             /* close_handle */
 135     no_destroy                   /* destroy */
 136 };
 137
 138
 139 struct event *create_event( struct object *root, const struct unicode_str *name,
 140                             unsigned int attr, int manual_reset, int initial_state,
 141                             const struct security_descriptor *sd )
 142 {
 143     struct event *event;
 144
 145     if ((event = create_named_object( root, &event_ops, name, attr, sd )))
 146     {
 147         if (get_error() != STATUS_OBJECT_NAME_EXISTS)
 148         {
 149             /* initialize it if it didn't already exist */
 150             list_init( &event->kernel_object );
 151             event->manual_reset = manual_reset;
 152             event->signaled     = initial_state;
 153         }
 154     }
 155     return event;
 156 }
 157
 158 struct event *get_event_obj( struct process *process, obj_handle_t handle, unsigned int access )
 159 {
 160     return (struct event *)get_handle_obj( process, handle, access, &event_ops );
 161 }
 162
 163 static void pulse_event( struct event *event )
 164 {
 165     event->signaled = 1;
 166     /* wake up all waiters if manual reset, a single one otherwise */
 167     wake_up( &event->obj, !event->manual_reset );
 168     event->signaled = 0;
 169 }
 170
 171 void set_event( struct event *event )
 172 {
 173     event->signaled = 1;
 174     /* wake up all waiters if manual reset, a single one otherwise */
 175     wake_up( &event->obj, !event->manual_reset );
 176 }
 177
 178 void reset_event( struct event *event )
 179 {
 180     event->signaled = 0;
 181 }
 182
 183 static void event_dump( struct object *obj, int verbose )
 184 {
 185     struct event *event = (struct event *)obj;
 186     assert( obj->ops == &event_ops );
 187     fprintf( stderr, "Event manual=%d signaled=%d\n",
 188              event->manual_reset, event->signaled );
 189 }
 190
 191 static int event_signaled( struct object *obj, struct wait_queue_entry *entry )
 192 {
 193     struct event *event = (struct event *)obj;
 194     assert( obj->ops == &event_ops );
 195     return event->signaled;
 196 }
 197
 198 static void event_satisfied( struct object *obj, struct wait_queue_entry *entry )
 199 {
 200     struct event *event = (struct event *)obj;
 201     assert( obj->ops == &event_ops );
 202     /* Reset if it's an auto-reset event */
 203     if (!event->manual_reset) event->signaled = 0;
 204 }
 205
 206 static int event_signal( struct object *obj, unsigned int access )
 207 {
 208     struct event *event = (struct event *)obj;
 209     assert( obj->ops == &event_ops );
 210
 211     if (!(access & EVENT_MODIFY_STATE))
 212     {
 213         set_error( STATUS_ACCESS_DENIED );
 214         return 0;
 215     }
 216     set_event( event );
 217     return 1;
 218 }
 219
 220 static struct list *event_get_kernel_obj_list( struct object *obj )
 221 {
 222     struct event *event = (struct event *)obj;
 223     return &event->kernel_object;
 224 }
 225
 226 struct keyed_event *create_keyed_event( struct object *root, const struct unicode_str *name,
 227                                         unsigned int attr, const struct security_descriptor *sd )
 228 {
 229     struct keyed_event *event;
 230
 231     if ((event = create_named_object( root, &keyed_event_ops, name, attr, sd )))
 232     {
 233         if (get_error() != STATUS_OBJECT_NAME_EXISTS)
 234         {
 235             /* initialize it if it didn't already exist */
 236         }
 237     }
 238     return event;
 239 }
 240
 241 struct keyed_event *get_keyed_event_obj( struct process *process, obj_handle_t handle, unsigned int access )
 242 {
 243     return (struct keyed_event *)get_handle_obj( process, handle, access, &keyed_event_ops );
 244 }
 245
 246 static void keyed_event_dump( struct object *obj, int verbose )
 247 {
 248     fputs( "Keyed event\n", stderr );
 249 }
 250
 251 static enum select_op matching_op( enum select_op op )
 252 {
 253     return op ^ (SELECT_KEYED_EVENT_WAIT ^ SELECT_KEYED_EVENT_RELEASE);
 254 }
 255
 256 static int keyed_event_signaled( struct object *obj, struct wait_queue_entry *entry )
 257 {
 258     struct wait_queue_entry *ptr;
 259     struct process *process;
 260     enum select_op select_op;
 261
 262     assert( obj->ops == &keyed_event_ops );
 263
 264     process = get_wait_queue_thread( entry )->process;
 265     select_op = get_wait_queue_select_op( entry );
 266     if (select_op != SELECT_KEYED_EVENT_WAIT && select_op != SELECT_KEYED_EVENT_RELEASE) return 1;
 267
 268     LIST_FOR_EACH_ENTRY( ptr, &obj->wait_queue, struct wait_queue_entry, entry )
 269     {
 270         if (ptr == entry) continue;
 271         if (get_wait_queue_thread( ptr )->process != process) continue;
 272         if (get_wait_queue_select_op( ptr ) != matching_op( select_op )) continue;
 273         if (get_wait_queue_key( ptr ) != get_wait_queue_key( entry )) continue;
 274         if (wake_thread_queue_entry( ptr )) return 1;
 275     }
 276     return 0;
 277 }
 278
 279 /* create an event */
 280 DECL_HANDLER(create_event)
 281 {
 282     struct event *event;
 283     struct unicode_str name;
 284     struct object *root;
 285     const struct security_descriptor *sd;
 286     const struct object_attributes *objattr = get_req_object_attributes( &sd, &name, &root );
 287
 288     if (!objattr) return;
 289
 290     if ((event = create_event( root, &name, objattr->attributes,
 291                                req->manual_reset, req->initial_state, sd )))
 292     {
 293         if (get_error() == STATUS_OBJECT_NAME_EXISTS)
 294             reply->handle = alloc_handle( current->process, event, req->access, objattr->attributes );
 295         else
 296             reply->handle = alloc_handle_no_access_check( current->process, event,
 297                                                           req->access, objattr->attributes );
 298         release_object( event );
 299     }
 300
 301     if (root) release_object( root );
 302 }
 303
 304 /* open a handle to an event */
 305 DECL_HANDLER(open_event)
 306 {
 307     struct unicode_str name = get_req_unicode_str();
 308
 309     reply->handle = open_object( current->process, req->rootdir, req->access,
 310                                  &event_ops, &name, req->attributes );
 311 }
 312
 313 /* do an event operation */
 314 DECL_HANDLER(event_op)
 315 {
 316     struct event *event;
 317
 318     if (!(event = get_event_obj( current->process, req->handle, EVENT_MODIFY_STATE ))) return;
 319     reply->state = event->signaled;
 320     switch(req->op)
 321     {
 322     case PULSE_EVENT:
 323         pulse_event( event );
 324         break;
 325     case SET_EVENT:
 326         set_event( event );
 327         break;
 328     case RESET_EVENT:
 329         reset_event( event );
 330         break;
 331     default:
 332         set_error( STATUS_INVALID_PARAMETER );
 333         break;
 334     }
 335     release_object( event );
 336 }
 337
 338 /* return details about the event */
 339 DECL_HANDLER(query_event)
 340 {
 341     struct event *event;
 342
 343     if (!(event = get_event_obj( current->process, req->handle, EVENT_QUERY_STATE ))) return;
 344
 345     reply->manual_reset = event->manual_reset;
 346     reply->state = event->signaled;
 347
 348     release_object( event );
 349 }
 350
 351 /* create a keyed event */
 352 DECL_HANDLER(create_keyed_event)
 353 {
 354     struct keyed_event *event;
 355     struct unicode_str name;
 356     struct object *root;
 357     const struct security_descriptor *sd;
 358     const struct object_attributes *objattr = get_req_object_attributes( &sd, &name, &root );
 359
 360     if (!objattr) return;
 361
 362     if ((event = create_keyed_event( root, &name, objattr->attributes, sd )))
 363     {
 364         if (get_error() == STATUS_OBJECT_NAME_EXISTS)
 365             reply->handle = alloc_handle( current->process, event, req->access, objattr->attributes );
 366         else
 367             reply->handle = alloc_handle_no_access_check( current->process, event,
 368                                                           req->access, objattr->attributes );
 369         release_object( event );
 370     }
 371     if (root) release_object( root );
 372 }
 373
 374 /* open a handle to a keyed event */
 375 DECL_HANDLER(open_keyed_event)
 376 {
 377     struct unicode_str name = get_req_unicode_str();
 378
 379     reply->handle = open_object( current->process, req->rootdir, req->access,
 380                                  &keyed_event_ops, &name, req->attributes );
 381 }