unevalutated Assignment 5

Assignment5/bitarr.c~

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+/*
+ * =====================================================================================
+ *
+ *       Filename:  bitarr.c
+ *
+ *    Description:  
+ *
+ *        Version:  1.0
+ *        Created:  Sunday 04 March 2018 06:23:30  IST
+ *       Revision:  1.0
+ *       Compiler:  gcc
+ *
+ *         Author:  Er. Abhishek Sagar, Networking Developer (AS), sachinites@gmail.com
+ *        Company:  Brocade Communications(Jul 2012- Mar 2016), Current : Juniper Networks(Apr 2017 - Present)
+ *        
+ *        This file is part of the SPFComputation distribution (https://github.com/sachinites).
+ *        Copyright (c) 2017 Abhishek Sagar.
+ *        This program is free software: you can redistribute it and/or modify
+ *        it under the terms of the GNU General Public License as published by  
+ *        the Free Software Foundation, version 3.
+ *
+ *        This program is distributed in the hope that it will be useful, but 
+ *        WITHOUT ANY WARRANTY; without even the implied warranty of 
+ *        MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 
+ *        General Public License for more details.
+ *
+ *        You should have received a copy of the GNU General Public License 
+ *        along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * =====================================================================================
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <memory.h>
+#include "bitsop.h"
+#include "bitarr.h"
+
+#define CHAR_SIZE   8
+
+void
+init_bit_array(bit_array_t *bitarr, unsigned int n_bits){
+
+    unsigned int n_byte_blocks = n_bits/CHAR_SIZE;
+
+    if(n_bits % CHAR_SIZE)
+        n_byte_blocks++;
+    if(!bitarr->array)
+        bitarr->array = calloc(1, n_byte_blocks);
+    else
+        memset(bitarr->array, 0, n_byte_blocks);
+    bitarr->size = n_bits;
+    bitarr->trail_bits = n_bits % CHAR_SIZE;
+}
+
+void
+set_bit(bit_array_t *bitarr, unsigned int index){
+
+    if(index >= bitarr->size){
+        printf("%u is out of array bounds [%u,%u]\n", 
+            index, 0, bitarr->size -1);
+        return;
+    }
+
+    unsigned byte_block = 0,
+             residual_bit = 0;
+
+    byte_block = index / CHAR_SIZE;
+    residual_bit = index % CHAR_SIZE;
+
+#if 0    
+    assert(bitarr->size/CHAR_SIZE == byte_block && 
+        bitarr->trail_bits >= residual_bit);
+#endif
+
+    char *ptr = bitarr->array + byte_block;
+    SET_BIT((*ptr), (CHAR_SIZE - residual_bit));
+}
+
+void
+unset_bit(bit_array_t *bitarr, unsigned int index){
+
+    if(index >= bitarr->size){
+        printf("%u is out of array bounds [%u,%u]\n", 
+            index, 0, bitarr->size -1);
+        return;
+    }
+
+    unsigned byte_block = 0,
+             residual_bit = 0;
+
+    byte_block = index / CHAR_SIZE;
+    residual_bit = index % CHAR_SIZE;
+
+#if 0
+    assert(bitarr->size/CHAR_SIZE == byte_block && 
+        bitarr->trail_bits >= residual_bit);
+#endif
+
+    char *ptr = bitarr->array + byte_block;
+    UNSET_BIT((*ptr), (CHAR_SIZE - residual_bit));
+}
+
+char
+is_bit_set(bit_array_t *bitarr, unsigned int index){
+
+    
+    if(index >= bitarr->size){
+        printf("%u is out of array bounds [%u,%u]\n", 
+            index, 0, bitarr->size -1);
+        return 0;
+    }
+
+    unsigned byte_block = 0,
+             residual_bit = 0;
+
+    byte_block = index / CHAR_SIZE;
+    residual_bit = index % CHAR_SIZE;
+    
+#if 0
+    assert(bitarr->size/CHAR_SIZE == byte_block && 
+        bitarr->trail_bits >= residual_bit);
+#endif
+    char *ptr = bitarr->array + byte_block;
+    return (char)(IS_BIT_SET((*ptr), (CHAR_SIZE - residual_bit)));
+}
+
+unsigned int
+get_next_available_bit(bit_array_t *bitarr){
+
+    unsigned int i = 0;
+    for(; i < bitarr->size; i++){
+        if(is_bit_set(bitarr, i))
+            continue;
+        return i;
+    }
+    return 0xFFFFFFFF;
+}
+
+void
+print_bit_array(bit_array_t *bitarr){
+
+    unsigned int i = 0, index = 0,
+                 byte_blocks = 0,
+                 residual_bits = 0;
+
+    int j = 0;
+
+    byte_blocks = bitarr->size / CHAR_SIZE;
+    residual_bits = bitarr->size % CHAR_SIZE;
+    //assert(bitarr->trail_bits >= residual_bit);
+    char *ptr = bitarr->array;
+    char byte = 0;
+
+    for( ; i < byte_blocks; i++){
+        byte = *(ptr+i);
+        for(j = 7; j >= 0; j--, index++){
+            printf("[%u] : %c\n", index, IS_BIT_SET(byte, j) ? '1' : '0');
+        }
+    }
+
+    if(!residual_bits)
+        return;
+
+    byte = *(ptr+i);
+    for(j = 7; j >= CHAR_SIZE - residual_bits; j--, index++){
+        printf("[%u] : %c\n", index, IS_BIT_SET(byte, j) ? '1' : '0');
+    }
+}
+
+
+#if 0
+int
+main(int argc, char **argv){
+
+    bit_array_t *arr = calloc(1, sizeof(bit_array_t));
+    init_bit_array(arr, 15);
+    set_bit(arr, 11);
+    set_bit(arr, 21);
+    set_bit(arr, 30);
+    set_bit(arr, 3);
+    set_bit(arr, 33);
+    print_bit_array(arr);
+    unset_bit(arr, 11);
+    print_bit_array(arr);
+    return 0;
+}
+#endif