85 lines
2.4 KiB
Plaintext
Executable File
85 lines
2.4 KiB
Plaintext
Executable File
/*
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* mm-naive.c - The fastest, least memory-efficient malloc package.
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*
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* In this naive approach, a block is allocated by simply incrementing
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* the brk pointer. A block is pure payload. There are no headers or
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* footers. Blocks are never coalesced or reused. Realloc is
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* implemented directly using mm_malloc and mm_free.
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*
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* NOTE TO STUDENTS: Replace this header comment with your own header
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* comment that gives a high level description of your solution.
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include <assert.h>
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#include <unistd.h>
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#include <string.h>
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#include "mm.h"
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#include "memlib.h"
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/*********************************************************
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* NOTE TO STUDENTS: Before you do anything else, please
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* provide your team information in the following struct.
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********************************************************/
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team_t team = {
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// Team name
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"MA",
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// First member's full name
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"Marvin Aleksa",
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// First member's email address
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"marvin.aleksa@stud.uni-due.de",
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// Second member's full name (leave blank if none)
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"",
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// Second member's email address (leave blank if none)
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""
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};
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// single word (4) or double word (8) alignment
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#define ALIGNMENT 8
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// rounds up to the nearest multiple of ALIGNMENT
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#define ALIGN(size) (((size) + (ALIGNMENT-1)) & ~0x7)
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#define SIZE_T_SIZE (ALIGN(sizeof(size_t)))
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// mm_init - initialize the malloc package.
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int mm_init(void){
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return 0;
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}
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// mm_malloc - Allocate a block by incrementing the brk pointer. Always allocate a block whose size is a multiple of the alignment.
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void *mm_malloc(size_t size){
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int newsize = ALIGN(size + SIZE_T_SIZE);
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void *p = mem_sbrk(newsize);
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if (p == (void *)-1)
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return NULL;
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else {
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*(size_t *)p = size;
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return (void *)((char *)p + SIZE_T_SIZE);
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}
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}
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// mm_free - Freeing a block does nothing.
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void mm_free(void *ptr){
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}
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// mm_realloc - Implemented simply in terms of mm_malloc and mm_free
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void *mm_realloc(void *ptr, size_t size){
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// ATTENTION: You do not need to implement realloc for this assignment
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void *oldptr = ptr;
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void *newptr;
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size_t copySize;
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newptr = mm_malloc(size);
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if (newptr == NULL)
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return NULL;
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copySize = *(size_t *)((char *)oldptr - SIZE_T_SIZE);
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if (size < copySize)
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copySize = size;
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memcpy(newptr, oldptr, copySize);
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mm_free(oldptr);
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return newptr;
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}
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