95 lines
2.5 KiB
C
95 lines
2.5 KiB
C
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/************************************************************************/
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/* File Name : lc4_memory.c */
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/* Purpose : This file implements the linked_list helper functions */
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/* to manage the LC4 memory */
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/* */
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/* Author(s) : tjf and you */
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/************************************************************************/
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#include <stdio.h>
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#include "lc4_memory.h"
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/*
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* adds a new node to a linked list pointed to by head
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*/
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int add_to_list (row_of_memory** head,
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short unsigned int address,
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short unsigned int contents)
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{
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/* check to see if there is already an entry for this address and update the contents. no additional steps required in this case */
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/* allocate memory for a single node */
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/* populate fields in newly allocated node w/ address&contents, NULL for label and assembly */
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/* do not malloc() storage for label and assembly here - do it in parse_file() and reverse_assemble() */
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/* if *head is NULL, node created is the new head of the list! */
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/* otherwise, insert node into the list in address ascending order */
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/* return 0 for success, -1 if malloc fails */
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return 0 ;
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}
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/*
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* search linked list by address field, returns node if found
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*/
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row_of_memory* search_address (row_of_memory* head,
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short unsigned int address )
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{
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/* traverse linked list, searching each node for "address" */
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/* return pointer to node in the list if item is found */
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/* return NULL if list is empty or if "address" isn't found */
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return NULL ;
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}
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/*
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* search linked list by opcode field, returns node if found
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*/
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row_of_memory* search_opcode (row_of_memory* head,
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short unsigned int opcode )
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{
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/* opcode parameter is in the least significant 4 bits of the short int and ranges from 0-15 */
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/* see assignment instructions for a detailed description */
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/* traverse linked list until node is found with matching opcode in the most significant 4 bits
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AND "assembly" field of node is NULL */
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/* return pointer to node in the list if item is found */
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/* return NULL if list is empty or if no matching nodes */
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return NULL ;
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}
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void print_list (row_of_memory* head )
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{
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/* make sure head isn't NULL */
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/* print out a header */
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/* traverse linked list, print contents of each node */
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return ;
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}
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/*
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* delete entire linked list
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*/
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int delete_list (row_of_memory** head )
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{
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/* delete entire list node by node */
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/* set the list head pointer to NULL upon deletion */
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return 0 ;
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}
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