1/* $NetBSD: alloc.c,v 1.10 2007/12/12 22:55:42 lukem Exp $ */ 2 3/* 4 * Copyright (c) 2002 Marc Espie. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE OPENBSD PROJECT AND CONTRIBUTORS 16 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 18 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OPENBSD 19 * PROJECT OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 20 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 21 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 25 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28/* 29 * area-based allocation built on malloc/free 30 */ 31#include <sys/cdefs.h> 32__RCSID("$NetBSD: alloc.c,v 1.10 2007/12/12 22:55:42 lukem Exp $"); 33 34#include "sh.h" 35 36struct link { 37 struct link *prev; 38 struct link *next; 39}; 40 41Area * 42ainit(Area *ap) 43{ 44 ap->freelist = NULL; 45 return ap; 46} 47 48void 49afreeall(Area *ap) 50{ 51 struct link *l, *l2; 52 53 for (l = ap->freelist; l != NULL; l = l2) { 54 l2 = l->next; 55 free(l); 56 } 57 ap->freelist = NULL; 58} 59 60#define L2P(l) ( (void *)(((char *)(l)) + sizeof(struct link)) ) 61#define P2L(p) ( (struct link *)(((char *)(p)) - sizeof(struct link)) ) 62 63/* coverity[+alloc] */ 64void * 65alloc(size_t size, Area *ap) 66{ 67 struct link *l; 68 69 l = malloc(sizeof(struct link) + size); 70 if (l == NULL) 71 internal_errorf(1, "unable to allocate memory"); 72 l->next = ap->freelist; 73 l->prev = NULL; 74 if (ap->freelist) 75 ap->freelist->prev = l; 76 ap->freelist = l; 77 78 return L2P(l); 79} 80 81/* coverity[+alloc] */ 82/* coverity[+free : arg-0] */ 83void * 84aresize(void *ptr, size_t size, Area *ap) 85{ 86 struct link *l, *l2, *lprev, *lnext; 87 88 if (ptr == NULL) 89 return alloc(size, ap); 90 91 l = P2L(ptr); 92 lprev = l->prev; 93 lnext = l->next; 94 95 l2 = realloc(l, sizeof(struct link) + size); 96 if (l2 == NULL) 97 internal_errorf(1, "unable to allocate memory"); 98 if (lprev) 99 lprev->next = l2; 100 else 101 ap->freelist = l2; 102 if (lnext) 103 lnext->prev = l2; 104 105 return L2P(l2); 106} 107 108/* coverity[+free : arg-0] */ 109void 110afree(void *ptr, Area *ap) 111{ 112 struct link *l; 113 114 if (!ptr) 115 return; 116 117 l = P2L(ptr); 118 119 if (l->prev) 120 l->prev->next = l->next; 121 else 122 ap->freelist = l->next; 123 if (l->next) 124 l->next->prev = l->prev; 125 126 free(l); 127} 128