ack/modules/src/alloc/st_alloc.c

59 lines
1.1 KiB
C

/* $Header$ */
/*
* (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
* See the copyright notice in the ACK home directory, in the file "Copyright".
*/
/* st_alloc - get a structure from a free list. If no structures left,
create new ones.
The counterpart, st_free, is a macro, defined in alloc.h
*/
#include "alloc.h"
char *
st_alloc(phead, size, count)
char **phead;
register unsigned int size;
{
register char *p;
register long *q;
char *retval;
if (*phead == 0) {
while (count >= 1 && (p = malloc(size * count)) == 0) {
count >>= 1;
}
if (p == 0) {
No_Mem();
}
((_PALLOC_) p)->_A_next = 0;
while (--count) {
p += size;
((_PALLOC_) p)->_A_next = (_PALLOC_) (p - size);
}
*phead = p;
}
else p = *phead;
*phead = (char *) (((_PALLOC_)p)->_A_next);
retval = p;
q = (long *) p;
while (size >= 8*sizeof(long)) {
*q++ = 0;
*q++ = 0;
*q++ = 0;
*q++ = 0;
*q++ = 0;
*q++ = 0;
*q++ = 0;
*q++ = 0;
size -= 8*sizeof(long);
}
while (size >= sizeof(long)) {
*q++ = 0;
size -= sizeof(long);
}
p = (char *) q;
while (size--) *p++ = 0;
return retval;
}