stralloc.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/* All Rights Reserved */
/*
* University Copyright- Copyright (c) 1982, 1986, 1988
* The Regents of the University of California
* All Rights Reserved
*
* University Acknowledgment- Portions of this document are derived from
* software developed by the University of California, Berkeley, and its
* contributors.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
/*
* Copyright (c) 1993-1997, by Sun Microsystems, Inc.
* All rights reserved.
*/
/*
* mailx -- a modified version of a University of California at Berkeley
* mail program
*
* Memory allocation routines.
* Memory handed out here are reclaimed at the top of the command
* loop each time, so they need not be freed.
*/
#include "rcv.h"
#include <locale.h>
static void *lastptr; /* addr of last buffer allocated */
static struct strings *lastsp; /* last string space allocated from */
/*
* Allocate size more bytes of space and return the address of the
* first byte to the caller. An even number of bytes are always
* allocated so that the space will always be on a word boundary.
* The string spaces are of exponentially increasing size, to satisfy
* the occasional user with enormous string size requests.
*/
void *
salloc(unsigned size)
{
register char *t;
register unsigned s;
register struct strings *sp;
int index;
s = size;
#if defined(u3b) || defined(sparc)
s += 3; /* needs alignment on quad boundary */
s &= ~03;
#elif defined(i386)
s++;
s &= ~01;
#else
#error Unknown architecture!
#endif
index = 0;
for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++) {
if (sp->s_topFree == NOSTR && (STRINGSIZE << index) >= s)
break;
if (sp->s_nleft >= s)
break;
index++;
}
if (sp >= &stringdope[NSPACE])
panic("String too large");
if (sp->s_topFree == NOSTR) {
index = sp - &stringdope[0];
sp->s_topFree = (char *) calloc(STRINGSIZE << index,
(unsigned) 1);
if (sp->s_topFree == NOSTR) {
fprintf(stderr, gettext("No room for space %d\n"),
index);
panic("Internal error");
}
sp->s_nextFree = sp->s_topFree;
sp->s_nleft = STRINGSIZE << index;
}
sp->s_nleft -= s;
t = sp->s_nextFree;
sp->s_nextFree += s;
lastptr = t;
lastsp = sp;
return(t);
}
/*
* Reallocate size bytes of space and return the address of the
* first byte to the caller. The old data is copied into the new area.
*/
void *
srealloc(void *optr, unsigned size)
{
void *nptr;
/* if we just want to expand the last allocation, that's easy */
if (optr == lastptr) {
register unsigned s, delta;
register struct strings *sp = lastsp;
s = size;
#if defined(u3b) || defined(sparc)
s += 3; /* needs alignment on quad boundary */
s &= ~03;
#elif defined(i386)
s++;
s &= ~01;
#else
#error Unknown architecture!
#endif defined(u3b) || defined(sparc)
delta = s - (sp->s_nextFree - (char *)optr);
if (delta <= sp->s_nleft) {
sp->s_nextFree += delta;
sp->s_nleft -= delta;
return (optr);
}
}
nptr = salloc(size);
if (nptr)
memcpy(nptr, optr, size); /* XXX - copying too much */
return nptr;
}
/*
* Reset the string area to be empty.
* Called to free all strings allocated
* since last reset.
*/
void
sreset(void)
{
register struct strings *sp;
register int index;
if (noreset)
return;
minit();
index = 0;
for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++) {
if (sp->s_topFree == NOSTR)
continue;
sp->s_nextFree = sp->s_topFree;
sp->s_nleft = STRINGSIZE << index;
index++;
}
lastptr = NULL;
lastsp = NULL;
}