freebsd-src/lib/libstand/zalloc_malloc.c
1999-08-28 00:22:10 +00:00

198 lines
4.4 KiB
C

/*
* This module derived from code donated to the FreeBSD Project by
* Matthew Dillon <dillon@backplane.com>
*
* Copyright (c) 1998 The FreeBSD Project
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*
* $FreeBSD$
*/
/*
* MALLOC.C - malloc equivalent, runs on top of zalloc and uses sbrk
*/
#include "zalloc_defs.h"
static MemPool MallocPool;
#ifdef DMALLOCDEBUG
static int MallocMax;
static int MallocCount;
void mallocstats(void);
#endif
#ifdef malloc
#undef malloc
#undef free
#endif
#ifdef __alpha__
void
free_region(void *start, void *end)
{
zextendPool(&MallocPool, start, (caddr_t)end - (caddr_t)start);
zfree(&MallocPool, start, (caddr_t)end - (caddr_t)start);
}
#endif
void *
malloc(size_t bytes)
{
Guard *res;
#ifdef USEENDGUARD
bytes += MALLOCALIGN + 1;
#else
bytes += MALLOCALIGN;
#endif
while ((res = znalloc(&MallocPool, bytes)) == NULL) {
int incr = (bytes + BLKEXTENDMASK) & ~BLKEXTENDMASK;
char *base;
if ((base = sbrk(incr)) == (char *)-1)
return(NULL);
zextendPool(&MallocPool, base, incr);
zfree(&MallocPool, base, incr);
}
#ifdef DMALLOCDEBUG
if (++MallocCount > MallocMax)
MallocMax = MallocCount;
#endif
#ifdef USEGUARD
res->ga_Magic = GAMAGIC;
#endif
res->ga_Bytes = bytes;
#ifdef USEENDGUARD
*((char *)res + bytes - 1) = -2;
#endif
return((char *)res + MALLOCALIGN);
}
void
free(void *ptr)
{
size_t bytes;
if (ptr != NULL) {
Guard *res = (void *)((char *)ptr - MALLOCALIGN);
#ifdef USEGUARD
if (res->ga_Magic != GAMAGIC)
panic("free: guard1 fail @ %p", ptr);
res->ga_Magic = -1;
#endif
#ifdef USEENDGUARD
if (*((char *)res + res->ga_Bytes - 1) != -2)
panic("free: guard2 fail @ %p + %d", ptr, res->ga_Bytes - MALLOCALIGN);
*((char *)res + res->ga_Bytes - 1) = -1;
#endif
bytes = res->ga_Bytes;
zfree(&MallocPool, res, bytes);
#ifdef DMALLOCDEBUG
--MallocCount;
#endif
}
}
void *
calloc(size_t n1, size_t n2)
{
iaddr_t bytes = (iaddr_t)n1 * (iaddr_t)n2;
void *res;
if ((res = malloc(bytes)) != NULL) {
bzero(res, bytes);
#ifdef DMALLOCDEBUG
if (++MallocCount > MallocMax)
MallocMax = MallocCount;
#endif
}
return(res);
}
/*
* realloc() - I could be fancier here and free the old buffer before
* allocating the new one (saving potential fragmentation
* and potential buffer copies). But I don't bother.
*/
void *
realloc(void *ptr, size_t size)
{
void *res;
size_t old;
if ((res = malloc(size)) != NULL) {
if (ptr) {
old = *(size_t *)((char *)ptr - MALLOCALIGN) - MALLOCALIGN;
if (old < size)
bcopy(ptr, res, old);
else
bcopy(ptr, res, size);
free(ptr);
} else {
#ifdef DMALLOCDEBUG
if (++MallocCount > MallocMax)
MallocMax = MallocCount;
#ifdef EXITSTATS
if (DidAtExit == 0) {
DidAtExit = 1;
atexit(mallocstats);
}
#endif
#endif
}
}
return(res);
}
void *
reallocf(void *ptr, size_t size)
{
void *res;
if ((res = realloc(ptr, size)) == NULL)
free(ptr);
return(res);
}
#ifdef DMALLOCDEBUG
void
mallocstats(void)
{
printf("Active Allocations: %d/%d\n", MallocCount, MallocMax);
#ifdef ZALLOCDEBUG
zallocstats(&MallocPool);
#endif
}
#endif