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