mm.c

/* 
 * mm.c  -  Simple allocator based on explicit free lists and 
 *         	first fit placement. It uses boundary tags and
 * 			a circular doubly linked list to keep track of
 * 			free blocks.
 *
 * Each block has a header and footer of the form:
 * 
 *      31                     3  2  1  0 
 *      -----------------------------------
 *     | s  s  s  s  ... s  s  s  0  0  a/f
 *      ----------------------------------- 
 * 
 * where s are the meaningful size bits and a/f is set iff the
 * block is allocated (0=a/1=f). Every block follows the form:
 * 
 *      31             0
 *      ----------------
 *     | Header
 *      ------------------
 *     | prev_free_block  \
 *      ----------------   | - Payload when not free
 *     | next_free_block  /
 *      ------------------
 *     | Footer
 *      ----------------
 * 
 * Due to the size of the header and the bytes required to store
 * the next and previous pointers, the minsize of a free block MUST
 * be 4 words, or 2 DWORDS (16 bytes)
 * 
 * The list has the following form:
 *
 * begin                                                         end
 * heap                                                          heap  
 *  -----------------------------------------------------------------   
 * |  key   | hdr(8:a) |   pad   | zero or more usr blks | hdr(8:a) |
 *  -----------------------------------------------------------------
 *    four  | prologue |  four   |                       | epilogue |
 *    bytes | block    |  bytes  |                       | block    |
 *
 */

#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
#include "mm.h"
#include "memlib.h"


/* Team structure */
team_t team = {
	/* Team name */
	"Daniel Shchur",
	/* Full name */
	"Daniel Shchur",
	/* Email address */
	"daniel.shchur@huskers.unl.edu",
	"",""
};


/* $begin mallocmacros */
/* Basic constants and macros */

/* You can add more macros and constants in this section */
#define WSIZE       4       /* word size (bytes) */  
#define DSIZE       8       /* doubleword size (bytes) */
#define CHUNKSIZE  (1<<12)  /* initial heap size (bytes) */