projects / apple / boot.git / blame
| Commit | Line | Data |
|---|---|---|
| 14c7c974 A |
1 | /* |
| 2 | * Copyright (c) 1999 Apple Computer, Inc. All rights reserved. | |
| 3 | * | |
| 4 | * @APPLE_LICENSE_HEADER_START@ | |
| 5 | * | |
| 6 | * Portions Copyright (c) 1999 Apple Computer, Inc. All Rights | |
| 7 | * Reserved. This file contains Original Code and/or Modifications of | |
| 8 | * Original Code as defined in and that are subject to the Apple Public | |
| 9 | * Source License Version 1.1 (the "License"). You may not use this file | |
| 10 | * except in compliance with the License. Please obtain a copy of the | |
| 11 | * License at http://www.apple.com/publicsource and read it before using | |
| 12 | * this file. | |
| 13 | * | |
| 14 | * The Original Code and all software distributed under the License are | |
| 15 | * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER | |
| 16 | * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, | |
| 17 | * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, | |
| 18 | * FITNESS FOR A PARTICULAR PURPOSE OR NON- INFRINGEMENT. Please see the | |
| 19 | * License for the specific language governing rights and limitations | |
| 20 | * under the License. | |
| 21 | * | |
| 22 | * @APPLE_LICENSE_HEADER_END@ | |
| 23 | */ | |
| 24 | /* cache */ | |
| 25 | ||
| 26 | #import "cache.h" | |
| 27 | #import "libsa.h" | |
| 28 | ||
| 29 | cache_t *cacheInit( | |
| 30 | int nitems, | |
| 31 | int item_size | |
| 32 | ) | |
| 33 | { | |
| 34 | cache_t *cp; | |
| 35 | item_size += sizeof(item_t); | |
| 36 | cp = (cache_t *)malloc(sizeof(cache_t) + nitems * item_size); | |
| 37 | cp->nitems = nitems; | |
| 38 | cp->item_size = item_size; | |
| 39 | return cp; | |
| 40 | } | |
| 41 | ||
| 42 | /* | |
| 43 | * Either find an item in the cache, or find where it should go. | |
| 44 | * Returns 1 if found, 0 if not found. | |
| 45 | * This function assumes that if you find an empty slot, you will use it; | |
| 46 | * therefore, empty slots returned are marked valid. | |
| 47 | */ | |
| 48 | int cacheFind( | |
| 49 | cache_t *cp, | |
| 50 | int key1, | |
| 51 | int key2, | |
| 52 | char **ip | |
| 53 | ) | |
| 54 | { | |
| 55 | item_t *iip, *min_p; | |
| 56 | int i,j; | |
| 57 | ||
| 58 | for(i=j=0, iip = min_p = (item_t *)cp->storage; i < cp->nitems; i++) { | |
| 59 | if (iip->referenced && (iip->key1 == key1) && (iip->key2 == key2)) { | |
| 60 | *ip = iip->storage; | |
| 61 | if (iip->referenced < 65535) | |
| 62 | iip->referenced++; | |
| 63 | return 1; | |
| 64 | } | |
| 65 | if (iip->referenced < min_p->referenced) { | |
| 66 | min_p = iip; | |
| 67 | j = i; | |
| 68 | } | |
| 69 | iip = (item_t *)((char *)iip + cp->item_size); | |
| 70 | } | |
| 71 | *ip = min_p->storage; | |
| 72 | min_p->referenced = 1; | |
| 73 | min_p->key1 = key1; | |
| 74 | min_p->key2 = key2; | |
| 75 | return 0; | |
| 76 | } | |
| 77 | ||
| 78 | /* | |
| 79 | * Flush the cache. | |
| 80 | */ | |
| 81 | void cacheFlush( | |
| 82 | cache_t *cp | |
| 83 | ) | |
| 84 | { | |
| 85 | int i; | |
| 86 | item_t *ip; | |
| 87 | ||
| 88 | if (cp == 0) | |
| 89 | return; | |
| 90 | for(i=0, ip = (item_t *)cp->storage; i < cp->nitems; i++) { | |
| 91 | ip->referenced = 0; | |
| 92 | ip = (item_t *)((char *)ip + cp->item_size); | |
| 93 | } | |
| 94 | } |