76 lines
1.1 KiB
C
76 lines
1.1 KiB
C
#
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/*
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* C library -- alloc/free
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*/
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#define logical char *
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struct fb {
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logical size;
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char *next;
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};
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int freelist[] {
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0,
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-1,
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};
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logical slop 2;
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alloc(asize)
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logical asize;
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{
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register logical size;
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register logical np;
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register logical cp;
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if ((size = asize) == 0)
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return(0);
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size =+ 3;
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size =& ~01;
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for (;;) {
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for (cp=freelist; (np= cp->next) != -1; cp=np) {
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if (np->size>=size) {
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if (size+slop >= np->size) {
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cp->next = np->next;
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return(&np->next);
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}
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cp = cp->next = np+size;
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cp->size = np->size - size;
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cp->next = np->next;
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np->size = size;
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return(&np->next);
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}
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}
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asize = size<1024? 1024: size;
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if ((cp = sbrk(asize)) == -1) {
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return (-1);
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}
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cp->size = asize;
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free(&cp->next);
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}
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}
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free(aptr)
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char *aptr;
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{
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register logical ptr;
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register logical cp;
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register logical np;
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ptr = aptr-2;
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cp = freelist;
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while ((np = cp->next) < ptr)
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cp = np;
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if (ptr+ptr->size == np) {
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ptr->size =+ np->size;
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ptr->next = np->next;
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np = ptr;
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} else
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ptr->next = np;
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if (cp+cp->size == ptr) {
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cp->size =+ ptr->size;
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cp->next = ptr->next;
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} else
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cp->next = ptr;
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}
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