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Help How to unpack boot.img without ANDROID! and gzip magic

Q

quevon24

Lurker
I'm not a ROM dev, so can't really assist with anything in that thread. As for the Dropbox boot.img, it's a binary file, you probably can't easily extract anything from it, or you need the correct dev. tools to do it. I don't currently have access to Dropbox, so can't download and have a look at it myself.

Intel z2580, that's their quite new "Baytrail" x86 architecture CPUs, intended for low-power mobile applications. Seems to be quite a few new tablets using x86 now, rather than ARM.
 
mikedt said:
I'm not a ROM dev, so can't really assist with anything in that thread. As for the Dropbox boot.img, it's a binary file, you probably can't easily extract anything from it, or you need the correct dev. tools to do it. I don't currently have access to Dropbox, so can't download and have a look at it myself.
Click to expand...
The dropbox file is public, anyone can download it. Or any other method to get the device tree?
 
quevon24 said:
The dropbox file is public, anyone can download it. Or any other method to get the device tree?
Click to expand...

I'm in China, Dropbox is blocked, and currently can't make my VPNs work on the hotel internet. To get to the device tree for a Dell, would probably be via Dell's open source commitments I think. Wherever they are, Github?

BTW I bought a new Ramos i9s tablet at the weekend, has one of these Intel Atom "Baytrail" x86 CPUs in it, a Z3735F quad-core. The one I bought has Windows 10, and there's an Android version as well.

Gzip Magic? Do you have Linux, maybe there's something there that can extract it.
 
Last edited:
mikedt said:
I'm in China, Dropbox is blocked, and currently can't make my VPNs work on the hotel internet. To get to the device tree for a Dell, would probably be via Dell's open source commitments I think. Wherever they are, Github?

BTW I bought a new Ramos i9s tablet at the weekend, has one of these Intel Atom "Baytrail" x86 CPUs in it, a Z3735F quad-core. The one I bought has Windows 10, and there's an Android version as well.

Gzip Magic? Do you have Linux, maybe there's something there that can extract it.
Click to expand...
Ooooh i see, maybe i have found a way to unpack that file, if this works i will share it. Thanks for answering.
 
I'm assuming that you have Cygwin or a Linux PC you can use...

Use the attached unpack-bootimg.pl Perl script (contained in the unpack-bootimg.zip) to unpack your boot image file. Here's an example of when I did it:

Code: 
$ perl unpack-bootimg.pl Venue_8_WiFi_KK4.4.2v1.33.boot.img
Subroutine Cwd::cwd redefined at /usr/lib/perl5/5.14/i686-cygwin-threads-64int/Cwd.pm line 407.
Subroutine Cwd::fastcwd redefined at /usr/lib/perl5/5.14/i686-cygwin-threads-64int/Cwd.pm line 819.
Name "DynaLoader::CARP_NOT" used only once: possible typo at /usr/lib/perl5/5.14/Carp.pm line 345.
Name "Cwd::CARP_NOT" used only once: possible typo at /usr/lib/perl5/5.14/Carp.pm line 345.
Name "File::path::CARP_NOT" used only once: possible typo at /usr/lib/perl5/5.14/Carp.pm line 345.
Name "Exporter::CARP_NOT" used only once: possible typo at /usr/lib/perl5/5.14/Carp.pm line 345.

kernel written to Venue_8_WiFi_KK4.4.2v1.33.boot.img-kernel.gz
ramdisk written to Venue_8_WiFi_KK4.4.2v1.33.boot.img-ramdisk.cpio.gz

gzip: ../Venue_8_WiFi_KK4.4.2v1.33.boot.img-ramdisk.cpio.gz: decompression OK, trailing garbage ignored
19364 blocks

extracted ramdisk contents to directory Venue_8_WiFi_KK4.4.2v1.33.boot.img-ramdisk/

Cheers!
 

Attachments

scary alien said:
I'm assuming that you have Cygwin or a Linux PC you can use...

Use the attached unpack-bootimg.pl Perl script (contained in the unpack-bootimg.zip) to unpack your boot image file. Here's an example of when I did it:

Code: 
$ perl unpack-bootimg.pl Venue_8_WiFi_KK4.4.2v1.33.boot.img
Subroutine Cwd::cwd redefined at /usr/lib/perl5/5.14/i686-cygwin-threads-64int/Cwd.pm line 407.
Subroutine Cwd::fastcwd redefined at /usr/lib/perl5/5.14/i686-cygwin-threads-64int/Cwd.pm line 819.
Name "DynaLoader::CARP_NOT" used only once: possible typo at /usr/lib/perl5/5.14/Carp.pm line 345.
Name "Cwd::CARP_NOT" used only once: possible typo at /usr/lib/perl5/5.14/Carp.pm line 345.
Name "File::path::CARP_NOT" used only once: possible typo at /usr/lib/perl5/5.14/Carp.pm line 345.
Name "Exporter::CARP_NOT" used only once: possible typo at /usr/lib/perl5/5.14/Carp.pm line 345.

kernel written to Venue_8_WiFi_KK4.4.2v1.33.boot.img-kernel.gz
ramdisk written to Venue_8_WiFi_KK4.4.2v1.33.boot.img-ramdisk.cpio.gz

gzip: ../Venue_8_WiFi_KK4.4.2v1.33.boot.img-ramdisk.cpio.gz: decompression OK, trailing garbage ignored
19364 blocks

extracted ramdisk contents to directory Venue_8_WiFi_KK4.4.2v1.33.boot.img-ramdisk/

Cheers!
Click to expand...

Thanks for this, but i have a problem when try to unpack, show this lines:

kernel written to boot.img-kernel.gz
ramdisk written to boot.img-ramdisk.cpio.gz

removed old directory boot.img-ramdisk
cpio: ../init: You can not create a symbolic link to `sbin/modprobe': File system read-only
cpio: ../init: You can not create a symbolic link to `sbin/ueventd': File system read-only
cpio: ../init: You can not create a symbolic link to `sbin/watchdogd': File system read-only

gzip: ../boot.img-ramdisk.cpio.gz: decompression OK, trailing garbage ignored
19364 blocks
 
That looks like it's issues from previous unpacking attempts?

Try to start in a clean directory or make sure that the Venue_8_WiFi_KK4.4.2v1.33.boot.img-ramdisk folder inside your present working directory (i.e., your current directory) is empty.
 
scary alien said:
That looks like it's issues from previous unpacking attempts?

Try to start in a clean directory or make sure that the Venue_8_WiFi_KK4.4.2v1.33.boot.img-ramdisk folder inside your present working directory (i.e., your current directory) is empty.
Click to expand...

Thanks for you help, worked perfectly, now i have a new question, now i want to get my device tree with the mkvendor.sh on the cyanogenmod source build/tools/device folder, y run this line using the previusly boot.img extracted:

./build/tools/device/mkvendor.sh dell yellowtail ~/boot.img

But the problem is that that some files are missing, i got this:

Code: 
Arguments: dell yellowtail /home/quevon24/boot.img
Output will be in /home/quevon24/android/system/cm12/device/dell/yellowtail
gzip: ../boot.img-ramdisk.gz: No such file or directory
cpio: premature end of archive
cat: /tmp/quevon24/bootimg/boot.img-base: No such file or directory
cat: /tmp/quevon24/bootimg/boot.img-cmdline: No such file or directory
cat: /tmp/quevon24/bootimg/boot.img-pagesize: No such file or directory
cp: cannot stat
«/tmp/quevon24/bootimg/boot.img-zImage»: No such file or directory
Creating initial git repository.
~/android/system/cm12/device/dell/yellowtail ~/android/system/cm12
Reinitialized existing Git repository in /home/quevon24/android/system/cm12/device/dell/yellowtail/.git/
On master branch
nothing to commit, working directory clean
~/android/system/cm12
Done!
 
Honestly, I've not messed with building with CyanogenMod...however, it looks the first few posts of this thread might be helpful:


This was the first result returned for me via a Google search of "mkvendor.sh".

I forgot that you had questions re. your other thread for building CyanogenMod for your device...my bootable image packing/unpacking knowledge might not be too helpful for you re. that :).
 
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