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[wine/multimedia.git] / server / class.c
blob77c7c5807838f0567704075120f61f3b24ccb079
1 /*
2 * Server-side window class management
4 * Copyright (C) 2002 Mike McCormack
5 * Copyright (C) 2003 Alexandre Julliard
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with this library; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 #include "config.h"
23 #include "wine/port.h"
25 #include <assert.h>
26 #include <stdlib.h>
27 #include <stdio.h>
28 #include <string.h>
30 #include "wine/list.h"
32 #include "request.h"
33 #include "object.h"
34 #include "process.h"
35 #include "user.h"
36 #include "winuser.h"
38 struct window_class
40 struct list entry; /* entry in process list */
41 struct process *process; /* process owning the class */
42 int count; /* reference count */
43 int local; /* local class? */
44 atom_t atom; /* class atom */
45 void *instance; /* module instance */
46 unsigned int style; /* class style */
47 int win_extra; /* number of window extra bytes */
48 void *client_ptr; /* pointer to class in client address space */
49 int nb_extra_bytes; /* number of extra bytes */
50 char extra_bytes[1]; /* extra bytes storage */
53 static struct window_class *desktop_class;
55 static struct window_class *create_class( struct process *process, int extra_bytes, int local )
57 struct window_class *class;
59 if (!(class = mem_alloc( sizeof(*class) + extra_bytes - 1 ))) return NULL;
61 class->process = (struct process *)grab_object( process );
62 class->count = 0;
63 class->local = local;
64 class->nb_extra_bytes = extra_bytes;
65 memset( class->extra_bytes, 0, extra_bytes );
66 /* other fields are initialized by caller */
68 /* local classes have priority so we put them first in the list */
69 if (local) list_add_head( &process->classes, &class->entry );
70 else list_add_tail( &process->classes, &class->entry );
71 return class;
74 static struct window_class *get_desktop_class(void)
76 if (!desktop_class)
78 if (!(desktop_class = mem_alloc( sizeof(*desktop_class) - 1 ))) return NULL;
79 desktop_class->process = NULL;
80 desktop_class->count = 0;
81 desktop_class->local = 0;
82 desktop_class->nb_extra_bytes = 0;
83 desktop_class->atom = DESKTOP_ATOM;
84 desktop_class->instance = NULL;
85 desktop_class->style = CS_DBLCLKS;
86 desktop_class->win_extra = 0;
87 desktop_class->client_ptr = NULL;
89 return desktop_class;
92 static void destroy_class( struct window_class *class )
94 list_remove( &class->entry );
95 release_object( class->process );
96 free( class );
99 void destroy_process_classes( struct process *process )
101 struct list *ptr;
103 while ((ptr = list_head( &process->classes )))
105 struct window_class *class = LIST_ENTRY( ptr, struct window_class, entry );
106 destroy_class( class );
110 static struct window_class *find_class( struct process *process, atom_t atom, void *instance )
112 struct list *ptr;
114 LIST_FOR_EACH( ptr, &process->classes )
116 struct window_class *class = LIST_ENTRY( ptr, struct window_class, entry );
117 if (class->atom != atom) continue;
118 if (!instance || !class->local || class->instance == instance) return class;
120 if (atom == DESKTOP_ATOM) return get_desktop_class();
121 return NULL;
124 struct window_class *grab_class( struct process *process, atom_t atom,
125 void *instance, int *extra_bytes )
127 struct window_class *class = find_class( process, atom, instance );
128 if (class)
130 class->count++;
131 *extra_bytes = class->win_extra;
133 else set_error( STATUS_INVALID_HANDLE );
134 return class;
137 void release_class( struct window_class *class )
139 assert( class->count > 0 );
140 class->count--;
143 atom_t get_class_atom( struct window_class *class )
145 return class->atom;
148 void *get_class_client_ptr( struct window_class *class )
150 return class->client_ptr;
153 /* create a window class */
154 DECL_HANDLER(create_class)
156 struct window_class *class;
157 struct winstation *winstation;
159 if (!req->local && req->atom == DESKTOP_ATOM)
160 return; /* silently ignore attempts to create the desktop class */
162 class = find_class( current->process, req->atom, req->instance );
163 if (class && !class->local == !req->local)
165 set_win32_error( ERROR_CLASS_ALREADY_EXISTS );
166 return;
168 if (req->extra < 0 || req->extra > 4096 || req->win_extra < 0 || req->win_extra > 4096)
170 /* don't allow stupid values here */
171 set_error( STATUS_INVALID_PARAMETER );
172 return;
175 if (!(winstation = get_process_winstation( current->process, WINSTA_ACCESSGLOBALATOMS )))
176 return;
178 if (!grab_global_atom( winstation, req->atom ))
180 release_object( winstation );
181 return;
183 if (!(class = create_class( current->process, req->extra, req->local )))
185 release_global_atom( winstation, req->atom );
186 release_object( winstation );
187 return;
189 class->atom = req->atom;
190 class->instance = req->instance;
191 class->style = req->style;
192 class->win_extra = req->win_extra;
193 class->client_ptr = req->client_ptr;
194 release_object( winstation );
197 /* destroy a window class */
198 DECL_HANDLER(destroy_class)
200 struct window_class *class = find_class( current->process, req->atom, req->instance );
202 if (!class)
203 set_win32_error( ERROR_CLASS_DOES_NOT_EXIST );
204 else if (class->count)
205 set_win32_error( ERROR_CLASS_HAS_WINDOWS );
206 else
208 reply->client_ptr = class->client_ptr;
209 if (class != desktop_class) destroy_class( class );
214 /* set some information in a class */
215 DECL_HANDLER(set_class_info)
217 struct window_class *class = get_window_class( req->window );
219 if (!class) return;
221 if (req->flags && class->process != current->process)
223 set_error( STATUS_ACCESS_DENIED );
224 return;
227 if (req->extra_size > sizeof(req->extra_value) ||
228 req->extra_offset < -1 ||
229 req->extra_offset > class->nb_extra_bytes - (int)req->extra_size)
231 set_win32_error( ERROR_INVALID_INDEX );
232 return;
234 if ((req->flags & SET_CLASS_WINEXTRA) && (req->win_extra < 0 || req->win_extra > 4096))
236 set_error( STATUS_INVALID_PARAMETER );
237 return;
239 if (req->extra_offset != -1)
241 memcpy( &reply->old_extra_value, class->extra_bytes + req->extra_offset, req->extra_size );
243 else if (req->flags & SET_CLASS_EXTRA)
245 set_win32_error( ERROR_INVALID_INDEX );
246 return;
249 reply->old_atom = class->atom;
250 reply->old_style = class->style;
251 reply->old_extra = class->nb_extra_bytes;
252 reply->old_win_extra = class->win_extra;
253 reply->old_instance = class->instance;
255 if (req->flags & SET_CLASS_ATOM)
257 struct winstation *winstation = get_process_winstation( current->process,
258 WINSTA_ACCESSGLOBALATOMS );
259 if (!grab_global_atom( winstation, req->atom ))
261 release_object( winstation );
262 return;
264 release_global_atom( winstation, class->atom );
265 class->atom = req->atom;
266 release_object( winstation );
268 if (req->flags & SET_CLASS_STYLE) class->style = req->style;
269 if (req->flags & SET_CLASS_WINEXTRA) class->win_extra = req->win_extra;
270 if (req->flags & SET_CLASS_INSTANCE) class->instance = req->instance;
271 if (req->flags & SET_CLASS_EXTRA) memcpy( class->extra_bytes + req->extra_offset,
272 &req->extra_value, req->extra_size );