1 /* SPDX-License-Identifier: BSD-2-Clause */ 2 /* 3 * Copyright (c) 2014, Linaro Limited 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions are met: 8 * 9 * 1. Redistributions of source code must retain the above copyright notice, 10 * this list of conditions and the following disclaimer. 11 * 12 * 2. Redistributions in binary form must reproduce the above copyright notice, 13 * this list of conditions and the following disclaimer in the documentation 14 * and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 17 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 * POSSIBILITY OF SUCH DAMAGE. 27 */ 28 #ifndef KERNEL_HANDLE_H 29 #define KERNEL_HANDLE_H 30 31 #include <stdint.h> 32 33 struct handle_db { 34 void **ptrs; 35 size_t max_ptrs; 36 }; 37 38 #define HANDLE_DB_INITIALIZER { NULL, 0 } 39 40 /* 41 * Frees all internal data structures of the database, but does not free 42 * the db pointer. The database is safe to reuse after it's destroyed, it 43 * just be empty again. 44 */ 45 void handle_db_destroy(struct handle_db *db); 46 47 /* 48 * Allocates a new handle and assigns the supplied pointer to it, 49 * ptr must not be NULL. 50 * The function returns 51 * >= 0 on success and 52 * -1 on failure 53 */ 54 int handle_get(struct handle_db *db, void *ptr); 55 56 /* 57 * Deallocates a handle. Returns the assiciated pointer of the handle 58 * the the handle was valid or NULL if it's invalid. 59 */ 60 void *handle_put(struct handle_db *db, int handle); 61 62 /* 63 * Returns the assiciated pointer of the handle if the handle is a valid 64 * handle. 65 * Returns NULL on failure. 66 */ 67 void *handle_lookup(struct handle_db *db, int handle); 68 69 #endif /*KERNEL_HANDLE_H*/ 70