47 lines
901 B
C
47 lines
901 B
C
/* st_alloc - get a structure from a free list. If no structures left,
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create new ones. The structures for which this works are
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supposed to have as their first tag the string "next", which
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should be a pointer type.
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The counterpart, st_free, is a macro, defined in alloc.h
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*/
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#include "alloc.h"
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struct xxx {
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char *next;
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};
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char *
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st_alloc(phead, size, count)
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char **phead;
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register unsigned int size;
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{
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register char *p;
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char *retval;
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if (*phead == 0) {
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p = Malloc(size * count);
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((struct xxx *) p)->next = 0;
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while (--count) {
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p += size;
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((struct xxx *) p)->next = p - size;
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}
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*phead = p;
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}
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else p = *phead;
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*phead = ((struct xxx *)p)->next;
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retval = p;
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if (size >= sizeof(long)) {
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register long *q = (long *) p;
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do {
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*q++ = 0;
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size -= sizeof(long);
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} while (size >= sizeof(long));
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p = (char *) q;
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}
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while (size--) *p++ = 0;
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return retval;
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}
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