1 // SPDX-License-Identifier: BSD-2-Clause
2 /*
3 * Copyright (c) 2014, Linaro Limited
4 */
5
6 #include <tee_internal_api.h>
7 #include "handle.h"
8
9 /*
10 * Define the initial capacity of the database. It should be a low number
11 * multiple of 2 since some databases a likely to only use a few handles.
12 * Since the algorithm doubles up when growing it shouldn't cause a
13 * noticeable overhead on large databases.
14 */
15 #define HANDLE_DB_INITIAL_MAX_PTRS 4
16
handle_db_destroy(struct handle_db * db)17 void handle_db_destroy(struct handle_db *db)
18 {
19 if (db) {
20 TEE_Free(db->ptrs);
21 db->ptrs = NULL;
22 db->max_ptrs = 0;
23 }
24 }
25
handle_get(struct handle_db * db,void * ptr)26 int handle_get(struct handle_db *db, void *ptr)
27 {
28 size_t n = 0;
29 void *p = NULL;
30 size_t new_max_ptrs = 0;
31
32 if (!db || !ptr)
33 return -1;
34
35 /* Try to find an empty location */
36 for (n = 0; n < db->max_ptrs; n++) {
37 if (!db->ptrs[n]) {
38 db->ptrs[n] = ptr;
39 return n;
40 }
41 }
42
43 /* No location available, grow the ptrs array */
44 if (db->max_ptrs)
45 new_max_ptrs = db->max_ptrs * 2;
46 else
47 new_max_ptrs = HANDLE_DB_INITIAL_MAX_PTRS;
48 p = TEE_Realloc(db->ptrs, new_max_ptrs * sizeof(void *));
49 if (!p)
50 return -1;
51 db->ptrs = p;
52 TEE_MemFill(db->ptrs + db->max_ptrs, 0,
53 (new_max_ptrs - db->max_ptrs) * sizeof(void *));
54 db->max_ptrs = new_max_ptrs;
55
56 /* Since n stopped at db->max_ptrs there is an empty location there */
57 db->ptrs[n] = ptr;
58 return n;
59 }
60
handle_put(struct handle_db * db,int handle)61 void *handle_put(struct handle_db *db, int handle)
62 {
63 void *p = NULL;
64
65 if (!db || handle < 0 || (size_t)handle >= db->max_ptrs)
66 return NULL;
67
68 p = db->ptrs[handle];
69 db->ptrs[handle] = NULL;
70 return p;
71 }
72
handle_lookup(struct handle_db * db,int handle)73 void *handle_lookup(struct handle_db *db, int handle)
74 {
75 if (!db || handle < 0 || (size_t)handle >= db->max_ptrs)
76 return NULL;
77
78 return db->ptrs[handle];
79 }
80