xref: /optee_os/core/include/kernel/handle.h (revision 9403c583381528e7fb391e3769644cc9653cfbb6)
1 /*
2  * Copyright (c) 2014, Linaro Limited
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright notice,
9  * this list of conditions and the following disclaimer.
10  *
11  * 2. Redistributions in binary form must reproduce the above copyright notice,
12  * this list of conditions and the following disclaimer in the documentation
13  * and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
16  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
19  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
20  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
21  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
22  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
23  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
24  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
25  * POSSIBILITY OF SUCH DAMAGE.
26  */
27 #ifndef KERNEL_HANDLE_H
28 #define KERNEL_HANDLE_H
29 
30 #include <stdint.h>
31 
32 struct handle_db {
33 	void **ptrs;
34 	size_t max_ptrs;
35 };
36 
37 #define HANDLE_DB_INITIALIZER { NULL, 0 }
38 
39 /*
40  * Frees all internal data structures of the database, but does not free
41  * the db pointer. The database is safe to reuse after it's destroyed, it
42  * just be empty again.
43  */
44 void handle_db_destroy(struct handle_db *db);
45 
46 /*
47  * Allocates a new handle and assigns the supplied pointer to it,
48  * ptr must not be NULL.
49  * The function returns
50  * >= 0 on success and
51  * -1 on failure
52  */
53 int handle_get(struct handle_db *db, void *ptr);
54 
55 /*
56  * Deallocates a handle. Returns the assiciated pointer of the handle
57  * the the handle was valid or NULL if it's invalid.
58  */
59 void *handle_put(struct handle_db *db, int handle);
60 
61 /*
62  * Returns the assiciated pointer of the handle if the handle is a valid
63  * handle.
64  * Returns NULL on failure.
65  */
66 void *handle_lookup(struct handle_db *db, int handle);
67 
68 #endif /*KERNEL_HANDLE_H*/
69