| /* Well, here's my linux version of findsuper. |
| * I'm sure you coulda done it faster. :) |
| * IMHO there isn't as much interesting data to print in the |
| * linux superblock as there is in the SunOS superblock--disk geometry is |
| * not there...and linux seems to update the dates in all the superblocks. |
| * SunOS doesn't ever touch the backup superblocks after the fs is created, |
| * as far as I can tell, so the date is more interesting IMHO and certainly |
| * marks which superblocks are backup ones. |
| * |
| * This still doesn't handle disks >2G. |
| * |
| * I wanted to add msdos support, but I couldn't make heads or tails |
| * of the kernel include files to find anything I could look for in msdos. |
| * |
| * Reading every block of a Sun partition is fairly quick. Doing the |
| * same under linux (slower hardware I suppose) just isn't the same. |
| * It might be more useful to default to reading the first (second?) block |
| * on each cyl; however, if the disk geometry is wrong, this is useless. |
| * But ya could still get the cyl size to print the numbers as cyls instead |
| * of blocks... |
| * |
| * run this as (for example) |
| * findsuper /dev/hda |
| * findsuper /dev/hda 437760 1024 (my disk has cyls of 855*512) |
| * |
| * I suppose the next step is to figgure out a way to determine if |
| * the block found is the first superblock somehow, and if so, build |
| * a partition table from the superblocks found... but this is still |
| * useful as is. |
| * |
| * Steve |
| * ssd@nevets.oau.org |
| * ssd@mae.engr.ucf.edu |
| */ |
| |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <time.h> |
| |
| #include <linux/ext2_fs.h> |
| |
| |
| main(int argc, char *argv[]) |
| { |
| int i; |
| int skiprate=512; /* one sector */ |
| long sk=0; /* limited to 2G filesystems!! */ |
| FILE *f; |
| char *s; |
| time_t tm; |
| |
| struct ext2_super_block ext2; |
| /* interesting fields: EXT2_SUPER_MAGIC |
| * s_blocks_count s_log_block_size s_mtime s_magic s_lastcheck */ |
| |
| if (argc<2) { |
| fprintf(stderr, |
| "Usage: findsuper device [skiprate [start]]\n"); |
| exit(1); |
| } |
| if (argc>2) |
| skiprate=atoi(argv[2]); |
| if (skiprate<512) { |
| fprintf(stderr, |
| "Do you really want to skip less than a sector??\n"); |
| exit(2); |
| } |
| if (argc>3) |
| sk=atol(argv[3]); |
| if (sk<0) { |
| fprintf(stderr,"Have to start at 0 or greater,not %ld\n",sk); |
| exit(1); |
| } |
| f=fopen(argv[1],"r"); |
| if (!f) { |
| perror(argv[1]); |
| exit(1); |
| } |
| |
| /* Now, go looking for the superblock ! */ |
| printf(" thisoff block fs_blk_sz blksz grp last_mount\n"); |
| for (;!feof(f) && (i=fseek(f,sk,SEEK_SET))!= -1; sk+=skiprate){ |
| if (i=fread(&ext2,sizeof(ext2),1, f)!=1) { |
| perror("read failed"); |
| } else if (ext2.s_magic == EXT2_SUPER_MAGIC){ |
| tm = ext2.s_mtime; |
| s=ctime(&tm); |
| s[24]=0; |
| printf("%9ld %9ld %9ld %5ld %4d %s\n", sk, |
| sk/1024, ext2.s_blocks_count, |
| ext2.s_log_block_size, |
| ext2.s_block_group_nr, s); |
| } |
| } |
| printf("Failed on %d at %ld\n", i, sk); |
| fclose(f); |
| } |