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while (GET_SIZE(HDRP(bp)) != 0) { if (!GET_ALLOC(HDRP(bp)) && (GET_SIZE(HDRP(bp)) >= new_size)) { set_allocated(bp, new_size); return bp; } bp = NEXT_BLKP(bp);}

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void *best_bp = NULL; while (GET_SIZE(HDRP(bp)) != 0) { if (!GET_ALLOC(HDRP(bp)) && (GET_SIZE(HDRP(bp)) >= new_size)) { if (!best_bp || (GET_SIZE(HDRP(bp)) < GET_SIZE(HDRP(best_bp)))) best_bp = bp; } bp = NEXT_BLKP(bp);}if (best_bp) { set_allocated(best_bp, new_size); return best_bp;}

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typedef size_t block_header; typedef size_t block_footer;

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#include <stdio.h>#include <stdlib.h> #define GET(p) (*(size_t *)(p))#define PUT(p, val) (*(size_t *)(p) = (val)) #define GET_ALLOC(p) (GET(p) & 0x1)#define GET_SIZE(p) (GET(p) & ~0xF) #define PACK(size, alloc) ((size) | (alloc)) int main() { void *p = malloc(sizeof(size_t)); PUT(p, PACK(48, 1)); printf("%ld %s\n", GET_SIZE(p), (GET_ALLOC(p) ? "alloc" : "unalloc"));}

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typedef int block_header;typedef int block_footer;#define GET(p) (*(int *)(p))#define PUT(p, val) (*(int *)(p) = (val))

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typedef struct list_node { struct list_node *prev; struct list_node *next;} list_node; .... void *mm_malloc(size_t size) { int need_size = max(size, sizeof(list_node)); int new_size = ALIGN(need_size + OVERHEAD); ....}

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Documents

my.eng.utah.educs4400/f17/malloc-2.pdfwhile (GET_SIZE(HDRP(bp)) != 0) {if (!GET_ALLOC(HDRP(bp)) && (GET_SIZE(HDRP(bp)) >= new_size)) {set_allocated(bp, new_size); return bp;} bp =