[Yaffs] Re: YAFFS fs images not working the way I expect

[Wookey]

+++ David Wuertele [04-10-27 15:06 -0700]:
> Charles> Have a look at the code for mkyaffs. This should give you a
> Charles> good kick-off point for programming YAFFS.
> 
> OK, after perusing mkyaffs.c, I am about to write a program for
> extracting data from a yaffs partition.
> 
> Instead of using
> 
>         dd if=/dev/mtd/2 of=/yaffs.img
> 
> I will use
> 
>         myprog /dev/mtd/2 > /yaffs.img
> 
> I think that "myprog" can be written by copying mkyaffs.c to
> readyaffs.c, removing the erase code, and changing the part that
> writes the data to this:
> 
>     if(addr) {
>         for(offset = 0; offset <meminfo.erasesize; offset+=512) {
>      	    lseek(fd,addr+offset,SEEK_SET);
>      	    if(read(fd,imgpage,512) == 512) {
>      	        oob.start = addr+offset;
>      	        oob.length=16;
>      	        oob.ptr=&imgpage[512];
>      	        ioctl(fd,MEMREADOOB,&oob);
>      	        write (1, imgpage, 528);
>      	    }
>      	}
>      }
> 
> Then, if I did this right, I should be able to run 
> 
>     /sbin/mkyaffs /dev/mtd/2 /yaffs.img
> 
> ...and everything will run normally.
> 
> Does that look right?

That looks about right - but you should be aware that a program to do this
already exists, called nanddump.c in the mtd utils dir. (It also has the
option to dump the output to Hex). If I were you I'd just use nanddump.


Wookey
-- 
Aleph One Ltd, Bottisham, CAMBRIDGE, CB5 9BA, UK  Tel +44 (0) 1223 811679
work: http://www.aleph1.co.uk/     play: http://www.chaos.org.uk/~wookey/