Move the name directive from the .spec file to the Makefile.
[wine/gsoc_dplay.git] / server / user.c
blobb4f3e0e571c8da2fbe4455174a30693cee71f161
1 /*
2 * Server-side USER handles
4 * Copyright (C) 2001 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
21 #include "thread.h"
22 #include "user.h"
24 struct user_handle
26 void *ptr; /* pointer to object */
27 unsigned short type; /* object type (0 if free) */
28 unsigned short generation; /* generation counter */
31 static struct user_handle *handles;
32 static struct user_handle *freelist;
33 static int nb_handles;
34 static int allocated_handles;
36 static struct user_handle *handle_to_entry( user_handle_t handle )
38 int index = (handle & 0xffff) - FIRST_USER_HANDLE;
39 if (index < 0 || index >= nb_handles) return NULL;
40 if (!handles[index].type) return NULL;
41 if ((handle >> 16) && (handle >> 16 != handles[index].generation)) return NULL;
42 return &handles[index];
45 inline static user_handle_t entry_to_handle( struct user_handle *ptr )
47 int index = ptr - handles;
48 return (index + FIRST_USER_HANDLE) + (ptr->generation << 16);
51 inline static struct user_handle *alloc_user_entry(void)
53 struct user_handle *handle;
55 if (freelist)
57 handle = freelist;
58 freelist = handle->ptr;
59 return handle;
61 if (nb_handles >= allocated_handles) /* need to grow the array */
63 struct user_handle *new_handles;
64 /* grow array by 50% (but at minimum 32 entries) */
65 int growth = max( 32, allocated_handles / 2 );
66 int new_size = min( allocated_handles + growth, LAST_USER_HANDLE-FIRST_USER_HANDLE+1 );
67 if (new_size <= allocated_handles) return NULL;
68 if (!(new_handles = realloc( handles, new_size * sizeof(*handles) )))
69 return NULL;
70 handles = new_handles;
71 allocated_handles = new_size;
73 handle = &handles[nb_handles++];
74 handle->generation = 0;
75 return handle;
78 inline static void *free_user_entry( struct user_handle *ptr )
80 void *ret;
81 ret = ptr->ptr;
82 ptr->ptr = freelist;
83 ptr->type = 0;
84 freelist = ptr;
85 return ret;
88 /* allocate a user handle for a given object */
89 user_handle_t alloc_user_handle( void *ptr, enum user_object type )
91 struct user_handle *entry = alloc_user_entry();
92 if (!entry) return 0;
93 entry->ptr = ptr;
94 entry->type = type;
95 if (++entry->generation >= 0xffff) entry->generation = 1;
96 return entry_to_handle( entry );
99 /* return a pointer to a user object from its handle */
100 void *get_user_object( user_handle_t handle, enum user_object type )
102 struct user_handle *entry;
104 if (!(entry = handle_to_entry( handle )) || entry->type != type) return NULL;
105 return entry->ptr;
108 /* get the full handle for a possibly truncated handle */
109 user_handle_t get_user_full_handle( user_handle_t handle )
111 struct user_handle *entry;
113 if (handle >> 16) return handle;
114 if (!(entry = handle_to_entry( handle ))) return handle;
115 return entry_to_handle( entry );
118 /* same as get_user_object plus set the handle to the full 32-bit value */
119 void *get_user_object_handle( user_handle_t *handle, enum user_object type )
121 struct user_handle *entry;
123 if (!(entry = handle_to_entry( *handle )) || entry->type != type) return NULL;
124 *handle = entry_to_handle( entry );
125 return entry->ptr;
128 /* free a user handle and return a pointer to the object */
129 void *free_user_handle( user_handle_t handle )
131 struct user_handle *entry;
133 if (!(entry = handle_to_entry( handle )))
135 set_error( STATUS_INVALID_HANDLE );
136 return NULL;
138 return free_user_entry( entry );
141 /* return the next user handle after 'handle' that is of a given type */
142 void *next_user_handle( user_handle_t *handle, enum user_object type )
144 struct user_handle *entry;
146 if (!*handle) entry = handles;
147 else
149 int index = (*handle & 0xffff) - FIRST_USER_HANDLE;
150 if (index < 0 || index >= nb_handles) return NULL;
151 entry = handles + index + 1; /* start from the next one */
153 while (entry < handles + nb_handles)
155 if (!type || entry->type == type)
157 *handle = entry_to_handle( entry );
158 return entry->ptr;
160 entry++;
162 return NULL;