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Diffstat (limited to 'lib/libc/alpha/stdlib/netbsd_malloc.c')
| -rw-r--r-- | lib/libc/alpha/stdlib/netbsd_malloc.c | 436 |
1 files changed, 0 insertions, 436 deletions
diff --git a/lib/libc/alpha/stdlib/netbsd_malloc.c b/lib/libc/alpha/stdlib/netbsd_malloc.c deleted file mode 100644 index 98d35bf..0000000 --- a/lib/libc/alpha/stdlib/netbsd_malloc.c +++ /dev/null @@ -1,436 +0,0 @@ -/* $Id$ -/* From: NetBSD: malloc.c,v 1.10 1997/07/21 14:08:55 jtc Exp */ - -/* - * Copyright (c) 1983 Regents of the University of California. - * All rights reserved. - * - * 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. - */ - -#include <sys/cdefs.h> - -/* - * malloc.c (Caltech) 2/21/82 - * Chris Kingsley, kingsley@cit-20. - * - * This is a very fast storage allocator. It allocates blocks of a small - * number of different sizes, and keeps free lists of each size. Blocks that - * don't exactly fit are passed up to the next larger size. In this - * implementation, the available sizes are 2^n-4 (or 2^n-10) bytes long. - * This is designed for use in a virtual memory environment. - */ - -/* include "namespace.h" */ -#if defined(DEBUG) || defined(RCHECK) || defined(MSTATS) -#include <stdio.h> -#endif -#include <sys/types.h> -#include <stdlib.h> -#include <string.h> -#include <unistd.h> - -#define NULL 0 - - -/* - * The overhead on a block is at least 4 bytes. When free, this space - * contains a pointer to the next free block, and the bottom two bits must - * be zero. When in use, the first byte is set to MAGIC, and the second - * byte is the size index. The remaining bytes are for alignment. - * If range checking is enabled then a second word holds the size of the - * requested block, less 1, rounded up to a multiple of sizeof(RMAGIC). - * The order of elements is critical: ov_magic must overlay the low order - * bits of ov_next, and ov_magic can not be a valid ov_next bit pattern. - */ -union overhead { - union overhead *ov_next; /* when free */ - struct { - u_char ovu_magic; /* magic number */ - u_char ovu_index; /* bucket # */ -#ifdef RCHECK - u_short ovu_rmagic; /* range magic number */ - u_long ovu_size; /* actual block size */ -#endif - } ovu; -#define ov_magic ovu.ovu_magic -#define ov_index ovu.ovu_index -#define ov_rmagic ovu.ovu_rmagic -#define ov_size ovu.ovu_size -}; - -#define MAGIC 0xef /* magic # on accounting info */ -#define RMAGIC 0x5555 /* magic # on range info */ - -#ifdef RCHECK -#define RSLOP sizeof (u_short) -#else -#define RSLOP 0 -#endif - -/* - * nextf[i] is the pointer to the next free block of size 2^(i+3). The - * smallest allocatable block is 8 bytes. The overhead information - * precedes the data area returned to the user. - */ -#define NBUCKETS 30 -static union overhead *nextf[NBUCKETS]; - -static int pagesz; /* page size */ -static int pagebucket; /* page size bucket */ - -#ifdef MSTATS -/* - * nmalloc[i] is the difference between the number of mallocs and frees - * for a given block size. - */ -static u_int nmalloc[NBUCKETS]; -#include <stdio.h> -#endif - -static void morecore __P((int)); -static int findbucket __P((union overhead *, int)); -#ifdef MSTATS -void mstats __P((char *)); -#endif - -#if defined(DEBUG) || defined(RCHECK) -#define ASSERT(p) if (!(p)) botch(__STRING(p)) - -static botch __P((char *)); - -static -botch(s) - char *s; -{ - fprintf(stderr, "\r\nassertion botched: %s\r\n", s); - (void) fflush(stderr); /* just in case user buffered it */ - abort(); -} -#else -#define ASSERT(p) -#endif - -void * -malloc(nbytes) - size_t nbytes; -{ - register union overhead *op; - register int bucket; - register long n; - register unsigned amt; - - /* - * First time malloc is called, setup page size and - * align break pointer so all data will be page aligned. - */ - if (pagesz == 0) { - pagesz = n = getpagesize(); - op = (union overhead *)sbrk(0); - n = n - sizeof (*op) - ((long)op & (n - 1)); - if (n < 0) - n += pagesz; - if (n) { - if (sbrk(n) == (char *)-1) - return (NULL); - } - bucket = 0; - amt = 8; - while (pagesz > amt) { - amt <<= 1; - bucket++; - } - pagebucket = bucket; - } - /* - * Convert amount of memory requested into closest block size - * stored in hash buckets which satisfies request. - * Account for space used per block for accounting. - */ - if (nbytes <= (n = pagesz - sizeof (*op) - RSLOP)) { -#ifndef RCHECK - amt = 8; /* size of first bucket */ - bucket = 0; -#else - amt = 16; /* size of first bucket */ - bucket = 1; -#endif - n = -((long)sizeof (*op) + RSLOP); - } else { - amt = pagesz; - bucket = pagebucket; - } - while (nbytes > amt + n) { - amt <<= 1; - if (amt == 0) - return (NULL); - bucket++; - } - /* - * If nothing in hash bucket right now, - * request more memory from the system. - */ - if ((op = nextf[bucket]) == NULL) { - morecore(bucket); - if ((op = nextf[bucket]) == NULL) - return (NULL); - } - /* remove from linked list */ - nextf[bucket] = op->ov_next; - op->ov_magic = MAGIC; - op->ov_index = bucket; -#ifdef MSTATS - nmalloc[bucket]++; -#endif -#ifdef RCHECK - /* - * Record allocated size of block and - * bound space with magic numbers. - */ - op->ov_size = (nbytes + RSLOP - 1) & ~(RSLOP - 1); - op->ov_rmagic = RMAGIC; - *(u_short *)((caddr_t)(op + 1) + op->ov_size) = RMAGIC; -#endif - return ((char *)(op + 1)); -} - -/* - * Allocate more memory to the indicated bucket. - */ -static void -morecore(bucket) - int bucket; -{ - register union overhead *op; - register long sz; /* size of desired block */ - long amt; /* amount to allocate */ - int nblks; /* how many blocks we get */ - - /* - * sbrk_size <= 0 only for big, FLUFFY, requests (about - * 2^30 bytes on a VAX, I think) or for a negative arg. - */ - sz = 1 << (bucket + 3); -#ifdef DEBUG - ASSERT(sz > 0); -#else - if (sz <= 0) - return; -#endif - if (sz < pagesz) { - amt = pagesz; - nblks = amt / sz; - } else { - amt = sz + pagesz; - nblks = 1; - } - op = (union overhead *)sbrk(amt); - /* no more room! */ - if ((long)op == -1) - return; - /* - * Add new memory allocated to that on - * free list for this hash bucket. - */ - nextf[bucket] = op; - while (--nblks > 0) { - op->ov_next = (union overhead *)((caddr_t)op + sz); - op = (union overhead *)((caddr_t)op + sz); - } -} - -void -free(cp) - void *cp; -{ - register long size; - register union overhead *op; - - if (cp == NULL) - return; - op = (union overhead *)((caddr_t)cp - sizeof (union overhead)); -#ifdef DEBUG - ASSERT(op->ov_magic == MAGIC); /* make sure it was in use */ -#else - if (op->ov_magic != MAGIC) - return; /* sanity */ -#endif -#ifdef RCHECK - ASSERT(op->ov_rmagic == RMAGIC); - ASSERT(*(u_short *)((caddr_t)(op + 1) + op->ov_size) == RMAGIC); -#endif - size = op->ov_index; - ASSERT(size < NBUCKETS); - op->ov_next = nextf[size]; /* also clobbers ov_magic */ - nextf[size] = op; -#ifdef MSTATS - nmalloc[size]--; -#endif -} - -/* - * When a program attempts "storage compaction" as mentioned in the - * old malloc man page, it realloc's an already freed block. Usually - * this is the last block it freed; occasionally it might be farther - * back. We have to search all the free lists for the block in order - * to determine its bucket: 1st we make one pass thru the lists - * checking only the first block in each; if that fails we search - * ``realloc_srchlen'' blocks in each list for a match (the variable - * is extern so the caller can modify it). If that fails we just copy - * however many bytes was given to realloc() and hope it's not huge. - */ -int realloc_srchlen = 4; /* 4 should be plenty, -1 =>'s whole list */ - -void * -realloc(cp, nbytes) - void *cp; - size_t nbytes; -{ - register u_long onb; - register long i; - union overhead *op; - char *res; - int was_alloced = 0; - - if (cp == NULL) - return (malloc(nbytes)); - if (nbytes == 0) { - free (cp); - return NULL; - } - op = (union overhead *)((caddr_t)cp - sizeof (union overhead)); - if (op->ov_magic == MAGIC) { - was_alloced++; - i = op->ov_index; - } else { - /* - * Already free, doing "compaction". - * - * Search for the old block of memory on the - * free list. First, check the most common - * case (last element free'd), then (this failing) - * the last ``realloc_srchlen'' items free'd. - * If all lookups fail, then assume the size of - * the memory block being realloc'd is the - * largest possible (so that all "nbytes" of new - * memory are copied into). Note that this could cause - * a memory fault if the old area was tiny, and the moon - * is gibbous. However, that is very unlikely. - */ - if ((i = findbucket(op, 1)) < 0 && - (i = findbucket(op, realloc_srchlen)) < 0) - i = NBUCKETS; - } - onb = 1 << (i + 3); - if (onb < pagesz) - onb -= sizeof (*op) + RSLOP; - else - onb += pagesz - sizeof (*op) - RSLOP; - /* avoid the copy if same size block */ - if (was_alloced) { - if (i) { - i = 1 << (i + 2); - if (i < pagesz) - i -= sizeof (*op) + RSLOP; - else - i += pagesz - sizeof (*op) - RSLOP; - } - if (nbytes <= onb && nbytes > i) { -#ifdef RCHECK - op->ov_size = (nbytes + RSLOP - 1) & ~(RSLOP - 1); - *(u_short *)((caddr_t)(op + 1) + op->ov_size) = RMAGIC; -#endif - return(cp); - } else - free(cp); - } - if ((res = malloc(nbytes)) == NULL) - return (NULL); - if (cp != res) /* common optimization if "compacting" */ - bcopy(cp, res, (nbytes < onb) ? nbytes : onb); - return (res); -} - -/* - * Search ``srchlen'' elements of each free list for a block whose - * header starts at ``freep''. If srchlen is -1 search the whole list. - * Return bucket number, or -1 if not found. - */ -static int -findbucket(freep, srchlen) - union overhead *freep; - int srchlen; -{ - register union overhead *p; - register int i, j; - - for (i = 0; i < NBUCKETS; i++) { - j = 0; - for (p = nextf[i]; p && j != srchlen; p = p->ov_next) { - if (p == freep) - return (i); - j++; - } - } - return (-1); -} - -#ifdef MSTATS -/* - * mstats - print out statistics about malloc - * - * Prints two lines of numbers, one showing the length of the free list - * for each size category, the second showing the number of mallocs - - * frees for each size category. - */ -void -mstats(s) - char *s; -{ - register int i, j; - register union overhead *p; - int totfree = 0, - totused = 0; - - fprintf(stderr, "Memory allocation statistics %s\nfree:\t", s); - for (i = 0; i < NBUCKETS; i++) { - for (j = 0, p = nextf[i]; p; p = p->ov_next, j++) - ; - fprintf(stderr, " %d", j); - totfree += j * (1 << (i + 3)); - } - fprintf(stderr, "\nused:\t"); - for (i = 0; i < NBUCKETS; i++) { - fprintf(stderr, " %d", nmalloc[i]); - totused += nmalloc[i] * (1 << (i + 3)); - } - fprintf(stderr, "\n\tTotal in use: %d, total free: %d\n", - totused, totfree); -} -#endif |
