/*
 * 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 1997 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*      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.
 */

/*
 * 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;
}