-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi Malte.
> There's no reason why the unified format couldn't be a tgz (or some other, > maybe uncompressed, format which carries a magic number) with some meta > informations :) Daniel's proposal sounded quite complicated to me. So I finally took some time to try the .tgz approach on a classic Fonera. As it turned out, the space in /tmp is not enough to store both the tgz and the unpacked images at the same time. To solve that I basically "invented" some simple image format with a two byte magic value in the beginning, followed by a 8 byte hex sequence descriping the length of the kernel image, a 16 byte space-padded string containing the name of the kernel mtd partition, a 8 byte hex-string containing the length of the rootfs image and a space-padded 16 byte string containing the name of the rootfs partition. the following 65486 bytes are space-padded to make the initial "header" stuff 64KB aligned. This initial 64KB block is concatenated together with the kernel lzma image and the rootfs image. The reason for doing such an awkward format is, that I wanted to be able to extract the sub-images with busybox' dd utility. Second step was to implement a platform.sh backend for sysupgrade which uses "dd" to extract name and length information from the first 64KB of the combined image. After determining the length information, "dd" is used again to extract the sub-images from the correct offsets in the combined image. The output is piped to the mtd utility. The configuration keeping is implemented with mtd's -j option when writing the rootfs. So far it seemed to work but I have only tested refleshing with the same images, need to try images of different size later. I've attached my platform.sh script and another script to generate a suitable combined image. I have no idea whether they will work with some other device than the Fonera, maybe someone want to try this out. Regards, JoW -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iEYEARECAAYFAko9LMMACgkQdputYINPTPOcCgCfWeLtMYS9VhMmb3bacXaJPzPn 9IsAn190+7UVtxyoOpK2+uSF94lVXJB1 =K16A -----END PGP SIGNATURE-----
mkimg.sh
Description: Bourne shell script
platform.sh
Description: Bourne shell script
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