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Diffstat (limited to 'lib/libstand/alloc.c')
| -rw-r--r-- | lib/libstand/alloc.c | 244 |
1 files changed, 0 insertions, 244 deletions
diff --git a/lib/libstand/alloc.c b/lib/libstand/alloc.c deleted file mode 100644 index 7fc63c1..0000000 --- a/lib/libstand/alloc.c +++ /dev/null @@ -1,244 +0,0 @@ -/* $NetBSD: alloc.c,v 1.11 1997/09/17 16:24:00 drochner Exp $ */ - -/* - * Copyright (c) 1997 Christopher G. Demetriou. All rights reserved. - * Copyright (c) 1996 - * Matthias Drochner. All rights reserved. - * Copyright (c) 1993 - * The Regents of the University of California. All rights reserved. - * - * This code is derived from software contributed to Berkeley by - * The Mach Operating System project at Carnegie-Mellon University. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * 3. All advertising materials mentioning features or use of this software - * must display the following acknowledgement: - * This product includes software developed by the University of - * California, Berkeley and its contributors. - * 4. Neither the name of the University nor the names of its contributors - * may be used to endorse or promote products derived from this software - * without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND - * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE - * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE - * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE - * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL - * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS - * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) - * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT - * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY - * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF - * SUCH DAMAGE. - * - * @(#)alloc.c 8.1 (Berkeley) 6/11/93 - * - * - * Copyright (c) 1989, 1990, 1991 Carnegie Mellon University - * All Rights Reserved. - * - * Author: Alessandro Forin - * - * Permission to use, copy, modify and distribute this software and its - * documentation is hereby granted, provided that both the copyright - * notice and this permission notice appear in all copies of the - * software, derivative works or modified versions, and any portions - * thereof, and that both notices appear in supporting documentation. - * - * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" - * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR - * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. - * - * Carnegie Mellon requests users of this software to return to - * - * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU - * School of Computer Science - * Carnegie Mellon University - * Pittsburgh PA 15213-3890 - * - * any improvements or extensions that they make and grant Carnegie the - * rights to redistribute these changes. - */ - -/* - * Dynamic memory allocator. - * - * Compile options: - * - * ALLOC_TRACE enable tracing of allocations/deallocations - - * ALLOC_FIRST_FIT use a first-fit allocation algorithm, rather than - * the default best-fit algorithm. - * - * HEAP_LIMIT heap limit address (defaults to "no limit"). - * - * HEAP_START start address of heap (defaults to '&end'). - * - * DEBUG enable debugging sanity checks. - */ - -#include <sys/param.h> -#include "stand.h" - -/* Default to variable heap operation */ -#define HEAP_VARIABLE -#define DEBUG - -/* - * Each block actually has ALIGN(size_t) + ALIGN(size) bytes allocated - * to it, as follows: - * - * 0 ... (sizeof(size_t) - 1) - * allocated or unallocated: holds size of user-data part of block. - * - * sizeof(size_t) ... (ALIGN(sizeof(size_t)) - 1) - * allocated: unused - * unallocated: depends on packing of struct fl - * - * ALIGN(sizeof(size_t)) ... (ALIGN(sizeof(size_t)) + ALIGN(data size) - 1) - * allocated: user data - * unallocated: depends on packing of struct fl - * - * 'next' is only used when the block is unallocated (i.e. on the free list). - * However, note that ALIGN(sizeof(size_t)) + ALIGN(data size) must - * be at least 'sizeof(struct fl)', so that blocks can be used as structures - * when on the free list. - */ -struct fl { - size_t size; - struct fl *next; -} *freelist = (struct fl *)0; - -#ifdef HEAP_VARIABLE -static char *top, *heapstart, *heaplimit; -void setheap(start, limit) -void *start, *limit; -{ - heapstart = top = start; - heaplimit = limit; -} -#define HEAP_START heapstart -#define HEAP_LIMIT heaplimit -#else /* !HEAP_VARIABLE */ -#ifndef HEAP_START -extern char end[]; -#define HEAP_START end -#endif -static char *top = (char*)HEAP_START; -#endif /* HEAP_VARIABLE */ - -void * -malloc(size) - size_t size; -{ - register struct fl **f = &freelist, **bestf = NULL; - size_t bestsize = 0xffffffff; /* greater than any real size */ - char *help; - int failed; - -#ifdef ALLOC_TRACE - printf("alloc(%u)", size); -#endif - -#ifdef ALLOC_FIRST_FIT - while (*f != (struct fl *)0 && (*f)->size < size) - f = &((*f)->next); - bestf = f; - failed = (*bestf == (struct fl *)0); -#else - /* scan freelist */ - while (*f) { - if ((*f)->size >= size) { - if ((*f)->size == size) /* exact match */ - goto found; - - if ((*f)->size < bestsize) { - /* keep best fit */ - bestf = f; - bestsize = (*f)->size; - } - } - f = &((*f)->next); - } - - /* no match in freelist if bestsize unchanged */ - failed = (bestsize == 0xffffffff); -#endif - - if (failed) { /* nothing found */ - /* - * allocate from heap, keep chunk len in - * first word - */ - help = top; - - /* make _sure_ the region can hold a struct fl. */ - if (size < ALIGN(sizeof (struct fl *))) - size = ALIGN(sizeof (struct fl *)); - top += ALIGN(sizeof(size_t)) + ALIGN(size); -#ifdef HEAP_LIMIT - if (top > (char*)HEAP_LIMIT) - panic("heap full (0x%lx+%u)", help, size); -#endif - *(size_t *)help = ALIGN(size); -#ifdef ALLOC_TRACE - printf("=%lx\n", (u_long)help + ALIGN(sizeof(size_t))); - getchar(); -#endif - return(help + ALIGN(sizeof(size_t))); - } - - /* we take the best fit */ - f = bestf; - -found: - /* remove from freelist */ - help = (char*)*f; - *f = (*f)->next; -#ifdef ALLOC_TRACE - printf("=%lx (origsize %u)\n", (u_long)help + ALIGN(sizeof(size_t)), - *(size_t *)help); - getchar(); -#endif - return(help + ALIGN(sizeof(size_t))); -} - -void -free(ptr) - void *ptr; -{ - register struct fl *f = - (struct fl *)((char*)ptr - ALIGN(sizeof(size_t))); -#ifdef ALLOC_TRACE - printf("free(%lx, %u) (origsize %u)\n", (u_long)ptr, size, f->size); - getchar(); -#endif -#ifdef DEBUG - if (ptr < (void *)HEAP_START) - printf("free: %lx before start of heap.\n", (u_long)ptr); - -#ifdef HEAP_LIMIT - if (ptr > (void *)HEAP_LIMIT) - printf("free: %lx beyond end of heap.\n", (u_long)ptr); -#endif -#endif /* DEBUG */ - /* put into freelist */ - f->next = freelist; - freelist = f; -} - -/* - * Emulate sbrk(0) behaviour - */ -char * -sbrk(int junk) -{ - return((char *)top); -} |
