[Yaffs] Re: YAFFS fs images not working the way I expect
Wookey
wookey@aleph1.co.uk
Tue, 2 Nov 2004 02:47:25 +0000
+++ 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
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