main.c

//Program: File System Checker
//Authors: Mark Freeman and Daniel Day

#include <stdio.h>
#include <stdlib.h>
#include "types.h"
#include "datatypes.h"
#include <fcntl.h>




s32 main(s32 argc, char *argv[]) {
	/*
	@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
	===========================================================
	MAIN
	===========================================================
	@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
	*/
        ext2_super_block backup_sb;
        BootSector boot_sector;
        u8 *inode_bitmap;
        u8 *block_bitmap;
        u8 *user_inode_bitmap; //inode bitmap created by program
        u8 *user_block_bitmap; //block bitmap created by program
        u32 inodes_per_block;
        inode_info* inode;
        int used_files = 0; //Existing files 
        int dir_count = 0; //Existing directories
        file = 0;
        directory = 0;


	printf("\n\n------------------------------\n");
	printf("\n      File System Check:\n\n");
	printf("------------------------------\n");
	printf("\n\nName of file: %s\n", argv[1]);

	vdi.fd = open(argv[1], O_RDONLY);
	if(vdi.fd == -1) {
		printf("Error:  FILE DOES NOT EXIST");
		return EXIT_FAILURE;
	}

	if(read_into_buffer(&vdi.hdr,0,sizeof(vdi.hdr)) == -1) {
		printf("Error.  VDI has not been read.\n");
		return EXIT_FAILURE;
	}

	if(read_VDI_map() == -1) {
		printf("Error.\n");
		return EXIT_FAILURE;
	}

	if(read_into_buffer(&boot_sector,VDI_translate(0),512) == -1) {
		printf("Error.\n");
		return EXIT_FAILURE;
	}

	vdi.start = get_partition_details(boot_sector);

	if(vdi.start == -1) {
		printf("Error.\n");
		return EXIT_FAILURE;
	}

	if(read_into_buffer(&main_sb,VDI_translate(vdi.start+1024),1024) == -1) {
		printf("Error.");
		return EXIT_FAILURE;
	}

        if(main_sb.s_state == EXT2_ERROR_FS) {
		printf("File System:  Not cleanly unmounted.  Checking for errors.\n");
	}

	if(vdi.hdr.drive_type == 1) printf("File type: Dynamic\n\n");
	else printf("File type: Static\n\n");

	printf("Total disk size: %llu bytes.\n", vdi.hdr.disk_size);

 	vdi.block_size = 1024 << main_sb.s_log_block_size;
	vdi.blocks_pg = main_sb.s_blocks_per_group;
	printf("The Superblock Magic Number: %x\n\n",main_sb.s_magic);
        
        if(main_sb.s_magic != 0xef53)
            printf("The magic number in the superblock is incorrect.\n");
        
        
	if(main_sb.s_blocks_count % main_sb.s_blocks_per_group == 0)
            vdi.no_groups =  main_sb.s_blocks_count / 	main_sb.s_blocks_per_group;

	else
            vdi.no_groups = (main_sb.s_blocks_count / main_sb.s_blocks_per_group) + 1;
        
        //define values for ext2 structures
 	temp_block = (u8*)malloc(vdi.block_size);
	printf("Total number of block groups: %u\n\n\n",vdi.no_groups);
        inodes_per_block = vdi.block_size/sizeof(inode_info);
        inodes_per_block = vdi.block_size/sizeof(inode_info);
        user_block_bitmap = (u8*)malloc(sizeof(u8) * main_sb.s_blocks_per_group * vdi.no_groups);
        user_inode_bitmap = (u8*)malloc(sizeof(u8) * main_sb.s_inodes_per_group * vdi.no_groups);
        desc_table = (bg_descriptor*)malloc(sizeof(bg_descriptor) * vdi.no_groups);
        inode_bitmap = (u8*)malloc(sizeof(u8) * main_sb.s_inodes_per_group/8);
        block_bitmap = (u8*)malloc(sizeof(u8) * main_sb.s_blocks_per_group/8);
        inode = (inode_info*)malloc(sizeof(inode_info));
        
        //Mark reserved inodes
        for(i = 0; i < 12; i++)
            user_inode_bitmap[i] = 1;
        
        //check superblock copies
	superblock_check(main_sb);

        get_bg_descriptor_table(desc_table, 0);
        
        //check block group descriptor table copies
	bg_desc_table_check(desc_table);
        for(i = 0; i < vdi.no_groups; i++){
            dir_count = dir_count + desc_table[i].bg_used_dirs_count;
        }
        used_files = main_sb.s_inodes_count - main_sb.s_free_inodes_count - dir_count;
        
        //Output Filesystem information
	dumpExt2File(used_files, dir_count );
        traverse_directory(2, user_block_bitmap, user_inode_bitmap);

        for (i = 0; i < vdi.no_groups ; i++){
            get_inode_bitmap(i,inode_bitmap);
            get_block_bitmap(i,block_bitmap);
            compare_inode_bitmap(i, user_inode_bitmap, inode_bitmap);
            compare_block_bitmap(i, user_block_bitmap, block_bitmap);
        }
        
        if(file == used_files)
             printf("Number of files is %i, which is the same\n", file);
        else
            printf("Files not the same. %i files found.\n", file);

        if(directory == dir_count)
                   printf("Number of directories is %i and they are the same. \n", directory);
        else
            printf("Number of directories not the same. %i Directories found.\n", directory);


	free(vdi.map);
	free(desc_table);
        free(user_block_bitmap);
        free(user_inode_bitmap);
        free(inode_bitmap);
        free(block_bitmap);

	if(close(vdi.fd) == -1) {
		printf("Error.\n");
		return EXIT_FAILURE;
	}



return EXIT_SUCCESS;
}