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Arquivotheca.Solaris-2.5/cmd/mailx/stralloc.c
seta75D 7c4988eac0 Init
2021-10-11 19:38:01 -03:00

140 lines
3.2 KiB
C
Executable File

/* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/* All Rights Reserved */
/* THIS IS UNPUBLISHED PROPRIETARY SOURCE CODE OF AT&T */
/* The copyright notice above does not evidence any */
/* actual or intended publication of such source code. */
#ident "@(#)stralloc.c 1.11 94/01/07 SMI" /* from SVr4.0 1.3.2.1 */
/*
* 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;
#else
s++;
s &= ~01;
#endif defined(u3b) || defined(sparc)
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;
#else
s++;
s &= ~01;
#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;
}