unformat格式化后的数据恢复源码

News: Version History: Version 0.1 First version, unformats quick-formatted DOS 6.22 hard drives. Program does not unformat floppy drives. Version 0.2 Second version, unformats floppy disks; but, terminates with an error as it completes unformatting the floppy drive. The floppy disk is completely and apparently successfully unformatted. Version 0.3 Removed 2 unnecessary libraries under the "includes" section. Temporarily fixed termination error when unformatting floppy disks. I'll have to look for a better solution, though. Version 0.4 Changed "cout" statements to "printf" statements for C compatibility. As an added bonus, removing the "iostream.h" library for "cout" and using "stdio.h" for "printf" reduced the executable size by 15K. there still may be a problem with the "dos.h" library and C code compatability. I also tested this program under Windows 95 in DOS mode with success. Note: Before running program in Windows 95's DOS mode type "lock" and when prompted, type "y" and [ENTER]. Version 0.5 Added /J function to verify the mirror image with the boot sector, the FAT tables, and the root directory. Added a message to let the user know that the unformat was successful. Removed the code that scans for the pointer to the mirror's location from the unformat function and made it a separate function to allow this function to be re-used by other parts of the program. Discovered that this program really does not work with Windows 95. Windows 95's format program does not write a mirror image to the disk. When I originally was testing my program, the test drive was running under DOS 6.22. When I was testing the program, I quick-formatted the hard drive under DOS 6.22. Then, I put the drive in a Windows 95 machine and tested it again without wiping the drive. So, the image was still there from DOS 6.22--oops! Found and fixed a bug in the unformatting loop for the FAT tables. The counter was off by 1. Version 0.6 Permanently fixed the problem unformatting the floppy drives as I mentioned in Version .3 and removed the temporary patch code. Added the /L function to list files and subdirectories in the root directory that were recovered. (A quick format only removes root directory information, it does not affect the subdirectories themselves.) Changed the variable names for the 2 total number of sectors variables. Fixed the bug that prevented the unformatting of FAT12 formatted hard disks. Found and fixed a bug that prevented the program from unformatting a drive with more than approx. 32767 sectors. Version 0.7 Major modifications to the code: Removed code that used interrupt 0x21 and replaced it with the code from the format command that determines the drive location and uses interrupt 0x13 for drive access. In consequence, the program now works with FreeDOS. Version 0.8 Now supports up to 8 hard disks. Fixed a bug that prevented the program from accessing sectors above sector 1677216. Added the /PARTN function to restore partition tables saved with the "MIRROR /PARTN" command for FreeDOS.